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Sample records for hevea brasiliensis clone

  1. Cloning and characterisation of JAZ gene family in Hevea brasiliensis.

    PubMed

    Hong, H; Xiao, H; Yuan, H; Zhai, J; Huang, X

    2015-05-01

    Mechanical wounding or treatment with exogenous jasmonates (JA) induces differentiation of the laticifer in Hevea brasiliensis. JA is a key signal for latex biosynthesis and wounding response in the rubber tree. Identification of JAZ (jasmonate ZIM-domain) family of proteins that repress JA responses has facilitated rapid progress in understanding how this lipid-derived hormone controls gene expression and related physiological processes in plants. In this work, the full-length cDNAs of six JAZ genes were cloned from H. brasiliensis (termed HbJAZ). These HbJAZ have different lengths and sequence diversity, but all of them contain Jas and ZIM domains, and two of them contain an ERF-associated amphiphilic repression (EAR) motif in the N-terminal. Real-time RT-PCR analyses revealed that HbJAZ have different expression patterns and tissue specificity. Four HbJAZ were up-regulated, one was down-regulated, while two were less effected by rubber tapping treatment, suggesting that they might play distinct roles in the wounding response. A yeast two-hybrid assay revealed that HbJAZ proteins interact with each other to form homologous or heterogeneous dimer complexes, indicating that the HbJAZ proteins may expand their function through diverse JAZ-JAZ interactions. This work lays a foundation for identification of the JA signalling pathway and molecular mechanisms of latex biosynthesis in rubber trees.

  2. Proteomics analysis of latex from Hevea brasiliensis (clone RRIM 600).

    PubMed

    Habib, Mohd Afiq Hazlami; Yuen, Gan Chee; Othman, Fazilah; Zainudin, Nurul Nabilah; Latiff, Aishah Abdul; Ismail, Mohd Nazri

    2017-04-01

    The natural rubber latex extracted from the bark of Hevea brasiliensis plays various important roles in today's modern society. Following ultracentrifugation, the latex can be separated into 3 layers: C-serum, lutoids, and rubber particles. Previous studies have shown that a large number of proteins are present in these 3 layers. However, a complete proteome for this important plant is still unavailable. Protein sequences have been recently translated from the completed draft genome database of H. brasiliensis, leading to the creation of annotated protein databases of the following H. brasiliensis biosynthetic pathways: photosynthesis, latex allergens, rubberwood formation, latex biosynthesis, and disease resistance. This research was conducted to identify the proteins contained within the latex by way of de novo sequencing from mass spectral data obtained from the 3 layers of the latex. Peptides from these proteins were fragmented using collision-induced dissociation, higher-energy collisional dissociation, and electron-transfer dissociation activation methods. A large percentage of proteins from the biosynthetic pathways (63% to 100%) were successfully identified. In addition, a total of 1839 unique proteins were identified from the whole translated draft genome database (AnnHBM).

  3. Studies of the latex of Brazilian IAC series clones from Hevea brasiliensis

    USDA-ARS?s Scientific Manuscript database

    Natural rubber is an important commodity industrial crop that mainly derives from Hevea brasiliensis. Most natural rubber production is in Southeast Asia, but significant cultivar development takes place in Brazil, the original origin of current commercial H. brasiliensis cultivars. Thus it is criti...

  4. Genomic validation of PB 260 clone of rubber (Hevea brasiliensis) at Cikumpay Plantation by SSR marker

    NASA Astrophysics Data System (ADS)

    Royani, J. I.; Safarrida, A.; Rachmawati, I.; Khairiyah, H.; Mustika, I. P.; Suyono, A.; Rudiyana, Y.; Kubil; Nurjaya; Arianto, A.

    2017-05-01

    Rubber from Hevea brasiliensis is the only commercial natural rubber in the world. Propagation of rubber trees usually done by grafting and seed germination. BPPT had been producing rubber tree by in vitro technique with embryo somatic methods. Validation of mother plant for in vitro propagation is important to compare between mother plant and propagated plants. The aim for this research was to validation of PB 260 clone that planted at Cikumpay Plantation by SSR marker. Sampling of 10 rubber leaves were done at Cikumpay Plantation based on GPS position from the area of PB 260 clone. Rubber leaves were isolated with CTAB modification method to obtained DNA. Four of SSR primers from rubber, i.e.: hmac 4, hmac 5, hmct 1, and hmct 5, were used as primers to amplification of rubber DNA. The result showed that no band that different from 10 rubber of PB 260 clone at Cikumpay Plantation. This research will continue to compare genomic validation between mother plant and propagated plants that had been produced from BPPT.

  5. Molecular cloning, expression profiles, and characterization of a novel polyphenol oxidase (PPO) gene in Hevea brasiliensis.

    PubMed

    Li, Dejun; Deng, Zhi; Liu, Changren; Zhao, Manman; Guo, Huina; Xia, Zhihui; Liu, Hui

    2014-01-01

    The polyphenol oxidase (PPO) is involved in undesirable browning in many plant foods. Although the PPOs have been studied by several researchers, the isolation and expression profiles of PPO gene were not reported in rubber tree. In this study, a new PPO gene, HbPPO, was isolated from Hevea brasiliensis. The sequence alignment showed that HbPPO indicated high identities to plant PPOs and belonged to dicot branch. The cis-acting regulatory elements related to stress/hormone responses were predicted in the promoter region of HbPPO. Real-time RT-PCR analyses showed that HbPPO expression varied widely depending on different tissues and developmental stages of leaves. Besides being associated with tapping panel dryness, the HbPPO transcripts were regulated by ethrel, wounding, H2O2, and methyl jasmonate treatments. Moreover, the correlation between latex coagulation rate and PPO activity was further confirmed in this study. Our results lay the foundation for further analyzing the function of HbPPO in rubber tree.

  6. Comparative Transcriptome Analysis of Latex Reveals Molecular Mechanisms Underlying Increased Rubber Yield in Hevea brasiliensis Self-Rooting Juvenile Clones

    PubMed Central

    Li, Hui-Liang; Guo, Dong; Zhu, Jia-Hong; Wang, Ying; Chen, Xiong-Ting; Peng, Shi-Qing

    2016-01-01

    Rubber tree (Hevea brasiliensis) self-rooting juvenile clones (JCs) are promising planting materials for rubber production. In a comparative trial between self-rooting JCs and donor clones (DCs), self-rooting JCs exhibited better performance in rubber yield. To study the molecular mechanism associated with higher rubber yield in self-rooting JCs, we sequenced and comparatively analyzed the latex of rubber tree self-rooting JCs and DCs at the transcriptome level. Total raw reads of 34,632,012 and 35,913,020 bp were obtained from the library of self-rooting JCs and DCs, respectively, by using Illumina HiSeq 2000 sequencing technology. De novo assemblies yielded 54689 unigenes from the library of self-rooting JCs and DCs. Among 54689 genes, 1716 genes were identified as differentially expressed between self-rooting JCs and DCs via comparative transcript profiling. Functional analysis showed that the genes related to the mass of categories were differentially enriched between the two clones. Several genes involved in carbohydrate metabolism, hormone metabolism and reactive oxygen species scavenging were up-regulated in self-rooting JCs, suggesting that the self-rooting JCs provide sufficient molecular basis for the increased rubber yielding, especially in the aspects of improved latex metabolisms and latex flow. Some genes encoding epigenetic modification enzymes were also differentially expressed between self-rooting JCs and DCs. Epigenetic modifications may lead to gene differential expression between self-rooting JCs and DCs. These data will provide new cues to understand the molecular mechanism underlying the improved rubber yield of H. brasiliensis self-rooting clones. PMID:27555864

  7. Rubber Tree (Hevea brasiliensis Muell. Arg).

    PubMed

    Venkatachalam, Perumal; Jayashree, Radha; Rekha, Karumamkandathil; Sushmakumari, Sreedharannair; Sobha, Sankaren; Kumari Jayasree, Parukkuttyamma; Kala, Radha Gopikkuttanunithan; Thulaseedharan, Arjunan

    2006-01-01

    Rubber tree (Hevea brasiliensis Muell. Arg.) is an important industrial crop for natural rubber production. At present, more than 9.5 million hectares in about 40 countries are devoted to rubber tree cultivation with a production about 6.5 million tons of dry rubber each year. The world supply of natural rubber is barely keeping up with a global demand for 12 million tons of natural rubber in 2020. Tapping panel dryness (TPD) is a complex physiological syndrome widely found in rubber tree plantations, which causes severe yield and crop losses in natural rubber producing countries. Currently, there is no effective prevention or treatment for this serious malady. As it is a perennial tree crop, the integration of specific desired traits through conventional breeding is both time-consuming and labour-intensive. Genetic transformation with conventional breeding is certainly a more promising tool for incorporation of agronomically important genes that could improve existing Hevea genotype. This chapter provides an Agrobacterium-mediated transformation protocol for rubber tree using immature anther-derived calli as initial explants. We have applied this protocol to generate genetically engineered plants from a high yielding Indian clone RRII 105 of Hevea brasiliensis (Hb). Calli were co-cultured with Agrobacterium tumefaciens harboring a plasmid vector containing the Hb superoxide dismutase (SOD) gene and the reporter gene used was beta-glucuronidase (GUS) gene (uidA). The selectable marker gene used was neomycin phosphotransferase (nptII) and kanamycin was used as selection agent. We found that a suitable transformation protocol for Hevea consists of a 3-d co-cultivation with Agrobacterium in the presence of 20 mM acetosyringone, 15 mM betaine HCl, and 11.55 mM proline followed by selection on medium containing 300 mg/L kanamycin. Transformed calli surviving on medium containing 300 mg/L kanamycin showed a strong GUS-positive reaction. Upon subsequent subculture into

  8. Draft genome sequence of the rubber tree Hevea brasiliensis

    PubMed Central

    2013-01-01

    Background Hevea brasiliensis, a member of the Euphorbiaceae family, is the major commercial source of natural rubber (NR). NR is a latex polymer with high elasticity, flexibility, and resilience that has played a critical role in the world economy since 1876. Results Here, we report the draft genome sequence of H. brasiliensis. The assembly spans ~1.1 Gb of the estimated 2.15 Gb haploid genome. Overall, ~78% of the genome was identified as repetitive DNA. Gene prediction shows 68,955 gene models, of which 12.7% are unique to Hevea. Most of the key genes associated with rubber biosynthesis, rubberwood formation, disease resistance, and allergenicity have been identified. Conclusions The knowledge gained from this genome sequence will aid in the future development of high-yielding clones to keep up with the ever increasing need for natural rubber. PMID:23375136

  9. Cloning and characterization of HbMT2a, a metallothionein gene from Hevea brasiliensis Muell. Arg differently responds to abiotic stress and heavy metals

    SciTech Connect

    Li, Yan; Chen, Yue Yi; Yang, Shu Guang; Tian, Wei Min

    2015-05-22

    Metallothioneins (MTs) are of low molecular mass, cysteine-rich proteins. They play an important role in the detoxification of heavy metals and homeostasis of intracellular metal ions, and protecting against intracellular oxidative damages. In this study a full-length cDNA of type 2 plant metallothioneins, HbMT2a, was isolated from 25 mM Polyethyleneglycol (PEG) stressed leaves of Hevea brasiliensis by RACE. The HbMT2a was 372 bp in length and had a 237 bp open reading frame (ORF) encoding for a protein of 78 amino acid residues with molecular mass of 7.772 kDa. The expression of HbMT2a in the detached leaves of rubber tree clone RY7-33-97 was up-regulated by Me-JA, ABA, PEG, H{sub 2}O{sub 2}, Cu{sup 2+} and Zn{sup 2+}, but down-regulated by water. The role of HbMT2a protein in protecting against metal toxicity was demonstrated in vitro. PET-28a-HbMT2-beared Escherichia coli. Differential expression of HbMT2a upon treatment with 10 °C was observed in the detached leaves of rubber tree clone 93-114 which is cold-resistant and Reken501 which is cold-sensitive. The expression patterns of HbMT2a in the two rubber tree clones may be ascribed to a change in the level of endogenous H{sub 2}O{sub 2}. - Highlights: • Cloning an HbMT2a gene from rubber tree. • Analyzing expression patterns of HbMT2a upon abiotic stress and heavy metal stress. • Finding different expression patterns of HbMT2a among two Hevea germplasm. • The expressed protein of HbMT2a enhances copper and zinc tolerance in Escherichia coli.

  10. Molecular cloning and characterization of a novel bi-functional α-amylase/subtilisin inhibitor from Hevea brasiliensis.

    PubMed

    Bunyatang, Orawan; Chirapongsatonkul, Nion; Bangrak, Phuwadol; Henry, Robert; Churngchow, Nunta

    2016-04-01

    A novel cDNA encoding a bi-functional α-amylase/subtilisin inhibitor (HbASI) was isolated from rubber (Hevea brasiliensis) leaves cultivar RRIM600. The HbASI had strong homology with the soybean trypsin inhibitor (Kunitz) family of protease inhibitors. Its putative amino acid sequence was similar to that of the α-amylase/subtilisin inhibitor from Ricinus communis (72% identity). Genomic sequencing indicated that the HbASI gene contained no introns. The messenger RNA of HbASI was detected in leaf, hypocotyl and root. The recombinant HbASI expressed extracellularly in Pichia pastoris exhibited inhibitory activity against α-amylase from Aspergillus oryzae, trypsin and subtilisin A. The HbASI gene was induced in the rubber leaves infected with a rubber tree pathogen, Phytophthora palmivora. It was also enhanced by salicylic acid (SA) treatment and mechanical wounding. In addition, the biological activity of the HbASI protein involving in the plant defence responses was also investigated. The HbASI at a concentration of 0.16 mg mL(-1) could inhibit the mycelium growth of P. palmivora. These data suggested that the HbASI protein might play a crucial role in defence against pathogen of rubber trees.

  11. Molecular cloning, expression profiles and characterization of a novel translationally controlled tumor protein in rubber tree (Hevea brasiliensis).

    PubMed

    Li, Dejun; Deng, Zhi; Liu, Xianghong; Qin, Bi

    2013-03-15

    The translationally controlled tumor protein (TCTP) is a multi-functioning protein that carries out vital roles in various life processes. In this study, a new TCTP gene, designated as HbTCTP1, was isolated in Hevea brasiliensis. The full-length complementary DNA (cDNA) of HbTCTP1 contained a maximum open reading frame (ORF) of 507base pair (bp) encoding 168 amino acids. The sequence comparison showed that the deduced HbTCTP1 indicated high identities to plant TCTP proteins, and clustered in the dicot cluster of plant TCTPs. Although HbTCTP1 and human TCTP proteins did not parallel in overall sequence similarity, they indicated highly similar 3D structures with a nearly identical spatial organization of α-helices, β-sheets, and coil regions. Real time reverse-transcription PCR (RT-PCR) analyses showed that HbTCTP1 was expressed throughout different tissues and developmental stages of leaves. Besides being related to tapping panel dryness (TPD), the HbTCTP1 transcripts were regulated by various treatments, including drought, low temperature, high salt, ethrel (ET), wounding, H2O2, and methyl jasmonate (Me-JA) treatments. The recombinant HbTCTP1 fusion protein was shown to protect supercoiled plasmid DNA from damages induced by metal-catalyzed generation of reactive oxygen species. The (45)Ca(2+)-overlay assay showed that HbTCTP1 was a calcium-binding protein. Our results are greatly helpful in understanding the molecular characterization and expression profiles of HbTCTP1, and lay the foundation for further analyzing the function of HbTCTP1 in rubber tree. Copyright © 2012 Elsevier GmbH. All rights reserved.

  12. Cloning and characterization of HbMT2a, a metallothionein gene from Hevea brasiliensis Muell. Arg differently responds to abiotic stress and heavy metals.

    PubMed

    Li, Yan; Chen, Yue Yi; Yang, Shu Guang; Tian, Wei Min

    2015-05-22

    Metallothioneins (MTs) are of low molecular mass, cysteine-rich proteins. They play an important role in the detoxification of heavy metals and homeostasis of intracellular metal ions, and protecting against intracellular oxidative damages. In this study a full-length cDNA of type 2 plant metallothioneins, HbMT2a, was isolated from 25 mM Polyethyleneglycol (PEG) stressed leaves of Hevea brasiliensis by RACE. The HbMT2a was 372bp in length and had a 237bp open reading frame (ORF) encoding for a protein of 78 amino acid residues with molecular mass of 7.772 kDa. The expression of HbMT2a in the detached leaves of rubber tree clone RY7-33-97 was up-regulated by Me-JA, ABA, PEG, H2O2, Cu(2+) and Zn(2+), but down-regulated by water. The role of HbMT2a protein in protecting against metal toxicity was demonstrated in vitro. PET-28a-HbMT2-beared Escherichia coli. Differential expression of HbMT2a upon treatment with 10 °C was observed in the detached leaves of rubber tree clone 93-114 which is cold-resistant and Reken501 which is cold-sensitive. The expression patterns of HbMT2a in the two rubber tree clones may be ascribed to a change in the level of endogenous H2O2.

  13. Cloning and characterization of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway genes of a natural-rubber producing plant, Hevea brasiliensis.

    PubMed

    Sando, Tomoki; Takeno, Shinya; Watanabe, Norie; Okumoto, Hiroshi; Kuzuyama, Tomohisa; Yamashita, Atsushi; Hattori, Masahira; Ogasawara, Naotake; Fukusaki, Eiichiro; Kobayashi, Akio

    2008-11-01

    Natural rubber is synthesized as rubber particles in the latex, the fluid cytoplasm of laticifers, of Hevea brasiliensis. Although it has been found that natural rubber is biosynthesized through the mevalonate pathway, the involvement of an alternative 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway is uncertain. We obtained all series of the MEP pathway candidate genes by analyzing expressed sequence tag (EST) information and degenerate PCR in H. brasiliensis. Complementation experiments with Escherichia coli mutants were performed to confirm the functions of the MEP pathway gene products of H. brasiliensis together with those of Arabidopsis thaliana, and it was found that 1-deoxy-D-xylulose-5-phosphate reductoisomerase, 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase, and 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase of H. brasiliensis were functionally active in the E. coli mutants. Gene expression analysis revealed that the expression level of the HbDXS2 gene in latex was relatively high as compared to those of other MEP pathway genes. However, a feeding experiment with [1-(13)C] 1-deoxy-D-xylulose triacetate, an intermediate derivative of the MEP pathway, indicated that the MEP pathway is not involved in rubber biosynthesis, but is involved in carotenoids biosynthesis in H. brasiliensis.

  14. Comparative study on the technological properties of latex and natural rubber from Hancornia speciosa Gomes and Hevea brasiliensis

    USDA-ARS?s Scientific Manuscript database

    This work reports a systematic comparative study of the properties of natural lattices and rubbers extracted from Hancornia speciosa Gomes and Hevea brasiliensis [(Willd. ex Adr. de Juss.) Muell.-Arg.] (clone RRIM 600) trees from 11 collections in Brazil throughout 2004. Natural rubber latex particl...

  15. Divergent DNA methylation patterns associated with abiotic stress in Hevea brasiliensis.

    PubMed

    Uthup, Thomas K; Ravindran, Minimol; Bini, K; Thakurdas, Saha

    2011-11-01

    Cytosine methylation is a fundamental epigenetic mechanism for gene-expression regulation and development in plants. Here, we report for the first time the identification of DNA methylation patterns and their putative relationship with abiotic stress in the tree crop Hevea brasiliensis (source of 99% of natural rubber in the world). Regulatory sequences of four major genes involved in the mevalonate pathway (rubber biosynthesis pathway) and one general defense-related gene of three high-yielding popular rubber clones grown at two different agroclimatic conditions were analyzed for the presence of methylation. We found several significant variations in the methylation pattern at core DNA binding motifs within all the five genes. Several consistent clone-specific and location-specific methylation patterns were identified. The differences in methylation pattern observed at certain pivotal cis-regulatory sites indicate the direct impact of stress on the genome and support the hypothesis of site-specific stress-induced DNA methylation. It is assumed that some of the methylation patterns observed may be involved in the stress-responsive mechanism in plants by which they adapt to extreme conditions. The study also provide clues towards the existence of highly divergent phenotypic characters among Hevea clones despite their very similar genetic make-up. Altogether, the observations from this study prove beyond doubt that there exist epigenetic variations in Hevea and environmental factors play a significant role in the induction of site-specific epigenetic mutations in its genome.

  16. Magnesium affects rubber biosynthesis and particle stability in Ficus elastica, Hevea brasiliensis and Parthenium argentatum

    USDA-ARS?s Scientific Manuscript database

    Natural rubber biosynthesis occurs in laticifers of Ficus elastica and Hevea brasiliensis, and in parenchyma cells of Parthenium argentatum. Natural rubber is synthesized by rubber transferase using allylic pyrophosphates as initiators, isopentenyl pyrophosphate as monomeric substrate and magnesium ...

  17. Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis.

    PubMed

    Putranto, Riza-Arief; Herlinawati, Eva; Rio, Maryannick; Leclercq, Julie; Piyatrakul, Piyanuch; Gohet, Eric; Sanier, Christine; Oktavia, Fetrina; Pirrello, Julien; Kuswanhadi; Montoro, Pascal

    2015-08-04

    Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD.

  18. Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis

    PubMed Central

    Putranto, Riza-Arief; Herlinawati, Eva; Rio, Maryannick; Leclercq, Julie; Piyatrakul, Piyanuch; Gohet, Eric; Sanier, Christine; Oktavia, Fetrina; Pirrello, Julien; Kuswanhadi; Montoro, Pascal

    2015-01-01

    Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD. PMID:26247941

  19. Assembly and Analysis of Differential Transcriptome Responses of Hevea brasiliensis on Interaction with Microcyclus ulei.

    PubMed

    Hurtado Páez, Uriel Alonso; García Romero, Ibonne Aydee; Restrepo Restrepo, Silvia; Aristizábal Gutiérrez, Fabio Ancizar; Montoya Castaño, Dolly

    2015-01-01

    Natural rubber (Hevea brasiliensis) is a tropical tree used commercially for the production of latex, from which 40,000 products are generated. The fungus Microcyclus ulei infects this tree, causing South American leaf blight (SALB) disease. This disease causes developmental delays and significant crop losses, thereby decreasing the production of latex. Currently several groups are working on obtaining clones of rubber tree with durable resistance to SALB through the use of extensive molecular biology techniques. In this study, we used a secondary clone that was resistant to M. ulei isolate GCL012. This clone, FX 3864 was obtained by crossing between clones PB 86 and B 38 (H. brasiliensis x H. brasiliensis). RNA-Seq high-throughput sequencing technology was used to analyze the differential expression of the FX 3864 clone transcriptome at 0 and 48 h post infection (hpi) with the M. ulei isolate GCL012. A total of 158,134,220 reads were assembled using the de novo assembly strategy to generate 90,775 contigs with an N50 of 1672. Using a reference-based assembly, 76,278 contigs were generated with an N50 of 1324. We identified 86 differentially expressed genes associated with the defense response of FX 3864 to GCL012. Seven putative genes members of the AP2/ERF ethylene (ET)-dependent superfamily were found to be down-regulated. An increase in salicylic acid (SA) was associated with the up-regulation of three genes involved in cell wall synthesis and remodeling, as well as in the down-regulation of the putative gene CPR5. The defense response of FX 3864 against the GCL012 isolate was associated with the antagonistic SA, ET and jasmonic acid (JA) pathways. These responses are characteristic of plant resistance to biotrophic pathogens.

  20. Assembly and Analysis of Differential Transcriptome Responses of Hevea brasiliensis on Interaction with Microcyclus ulei

    PubMed Central

    Restrepo Restrepo, Silvia; Aristizábal Gutiérrez, Fabio Ancizar; Montoya Castaño, Dolly

    2015-01-01

    Natural rubber (Hevea brasiliensis) is a tropical tree used commercially for the production of latex, from which 40,000 products are generated. The fungus Microcyclus ulei infects this tree, causing South American leaf blight (SALB) disease. This disease causes developmental delays and significant crop losses, thereby decreasing the production of latex. Currently several groups are working on obtaining clones of rubber tree with durable resistance to SALB through the use of extensive molecular biology techniques. In this study, we used a secondary clone that was resistant to M. ulei isolate GCL012. This clone, FX 3864 was obtained by crossing between clones PB 86 and B 38 (H. brasiliensis x H. brasiliensis). RNA-Seq high-throughput sequencing technology was used to analyze the differential expression of the FX 3864 clone transcriptome at 0 and 48 h post infection (hpi) with the M. ulei isolate GCL012. A total of 158,134,220 reads were assembled using the de novo assembly strategy to generate 90,775 contigs with an N50 of 1672. Using a reference-based assembly, 76,278 contigs were generated with an N50 of 1324. We identified 86 differentially expressed genes associated with the defense response of FX 3864 to GCL012. Seven putative genes members of the AP2/ERF ethylene (ET)-dependent superfamily were found to be down-regulated. An increase in salicylic acid (SA) was associated with the up-regulation of three genes involved in cell wall synthesis and remodeling, as well as in the down-regulation of the putative gene CPR5. The defense response of FX 3864 against the GCL012 isolate was associated with the antagonistic SA, ET and jasmonic acid (JA) pathways. These responses are characteristic of plant resistance to biotrophic pathogens. PMID:26287380

  1. Isolation of scopoletin from leaves of Hevea brasiliensis and the effect of scopoletin on pathogens of H. brasiliensis.

    PubMed

    Silva, W P K; Deraniyagala, S A; Wijesundera, R L C; Karunanayake, E H; Priyanka, U M S

    2002-01-01

    Scopoletin (7-hydroxy-6-methoxy coumarin) which inhibited the conidial germination of Corynespora cassiicola was isolated from the uninfected mature leaves of Hevea brasiliensis. Scopoletin was not detected in uninfected immature rubber leaves. The immature leaves produced scopoletin after being infected with C. cassiicola. The concentration of scopoletin in infected leaves was higher than in uninfected mature leaves. Scopoletin also inhibited the conidial germination of other fungal pathogens of H. brasiliensis. However, no correlation was observed between scopoletin accumulation and clonal resistance.

  2. Molecular evolution and functional characterisation of haplotypes of an important rubber biosynthesis gene in Hevea brasiliensis.

    PubMed

    Uthup, T K; Rajamani, A; Ravindran, M; Saha, T

    2016-07-01

    Hydroxy-methylglutaryl coenzyme-A synthase (HMGS) is a rate-limiting enzyme in the cytoplasmic isoprenoid biosynthesis pathway leading to natural rubber production in Hevea brasiliensis (rubber). Analysis of the structural variants of this gene is imperative to understand their functional significance in rubber biosynthesis so that they can be properly utilised for ongoing crop improvement programmes in Hevea. We report here allele richness and diversity of the HMGS gene in selected popular rubber clones. Haplotypes consisting of single nucleotide polymorphisms (SNPs) from the coding and non-coding regions with a high degree of heterozygosity were identified. Segregation and linkage disequilibrium analysis confirmed that recombination is the major contributor to the generation of allelic diversity, rather than point mutations. The evolutionarily conserved nature of some SNPs was identified by comparative DNA sequence analysis of HMGS orthologues from diverse taxa, demonstrating the molecular evolution of rubber biosynthesis genes in general. In silico three-dimensional structural studies highlighting the structural positioning of non-synonymous SNPs from different HMGS haplotypes revealed that the ligand-binding site on the enzyme remains impervious to the reported sequence variations. In contrast, gene expression results indicated the possibility of association between specific haplotypes and HMGS expression in Hevea clones, which may have a downstream impact up to the level of rubber production. Moreover, haplotype diversity of the HMGS gene and its putative association with gene expression can be the basis for further genetic association studies in rubber. Furthermore, the data also show the role of SNPs in the evolution of candidate genes coding for functional traits in plants.

  3. Highlights on Hevea brasiliensis (pro)hevein proteins.

    PubMed

    Berthelot, Karine; Peruch, Frédéric; Lecomte, Sophie

    2016-08-01

    Hevein, from Hevea brasiliensis (rubber tree), was identified in 1960. It is the most abundant soluble protein (22%) found in latex. Hevein is formed from a larger protein called prohevein. The 187 amino-acid prohevein is cleaved into two fragments: the N-terminal 43 amino-acid hevein, a lectin bearing a chitin-binding motif with antifungal properties, and a C-terminal domain (C-ter), which possesses amyloid properties. Hevein-like proteins are also widely represented in the plant kingdom and belong to a larger family related to stress and pathogenic responses. During the last 55 years, these proteins have attracted the interest of numerous specialists from the fields of plant physiology, genetics, molecular and structural biology, and physico-chemistry to allergology. This review highlights various aspects of hevein, prohevein, and C-ter from the point of view of these various fields, and examines their potential roles in latex as well as their beneficial and negative biological effects (e.g. wound sealing and resistance to pathogens which is mediated by agglutination, antimicrobial activity, and/or allergenicity). It covers results and observations from 1960 up to the most recent research.

  4. Metabolic routes affecting rubber biosynthesis in Hevea brasiliensis latex

    PubMed Central

    Chow, Keng-See; Mat-Isa, Mohd.-Noor; Bahari, Azlina; Ghazali, Ahmad-Kamal; Alias, Halimah; Mohd.-Zainuddin, Zainorlina; Hoh, Chee-Choong; Wan, Kiew-Lian

    2012-01-01

    The cytosolic mevalonate (MVA) pathway in Hevea brasiliensis latex is the conventionally accepted pathway which provides isopentenyl diphosphate (IPP) for cis-polyisoprene (rubber) biosynthesis. However, the plastidic 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway may be an alternative source of IPP since its more recent discovery in plants. Quantitative RT-PCR (qRT-PCR) expression profiles of genes from both pathways in latex showed that subcellular compartmentalization of IPP for cis-polyisoprene synthesis is related to the degree of plastidic carotenoid synthesis. From this, the occurrence of two schemes of IPP partitioning and utilization within one species is proposed whereby the supply of IPP for cis-polyisoprene from the MEP pathway is related to carotenoid production in latex. Subsequently, a set of latex unique gene transcripts was sequenced and assembled and they were then mapped to IPP-requiring pathways. Up to eight such pathways, including cis-polyisoprene biosynthesis, were identified. Our findings on pre- and post-IPP metabolic routes form an important aspect of a pathway knowledge-driven approach to enhancing cis-polyisoprene biosynthesis in transgenic rubber trees. PMID:22162870

  5. Cloning and Expression Analysis of One Gamma-Glutamylcysteine Synthetase Gene (Hbγ-ECS1) in Latex Production in Hevea brasiliensis

    PubMed Central

    Fang, Wei; Qiao, Luo Shi; Ming, Wu; Jian, Qiu; Feng, Yang Wen; Hua, Gao Hong; Zhou, Xiao Xian

    2016-01-01

    Rubber tree is a major commercial source of natural rubber. Latex coagulation is delayed by thiols, which belong to the important type of antioxidants in laticifer submembrane, and is composed of glutathione (GSH), cysteine, and methionine. The rate-limiting enzyme, γ-ECS, plays an important role in regulating the biosynthesis of glutathione under any environment conditions. To understand the relation between γ-ECS and thiols and to correlate latex flow with one-time tapping and continuous tapping, we cloned and derived the full length of one γ-ECS from rubber tree latex (Hbγ-ECS1). According to qPCR analysis, the expression levels of Hbγ-ECS1 were induced by tapping and Ethrel stimulation, and the expression was related to thiols content in the latex. Continuous tapping induced injury, and the expression of HbγECS1 increased with routine tapping and Ethrel-stimulation tapping (more intensive tapping). According to expression in long-term flowing latex, the gene was related to the duration of latex flow. HbγECS1 was expressed in E. coli Rosetta using pET-sumo as an expression vector and the recombinant enzyme was purified; then we achieved 0.827 U/mg specific activity and about 66 kDa molecular weight. The present study can help us understand the complex role of Hbγ-ECS in thiols biosynthesis, which is influenced by tapping. PMID:27419133

  6. Cloning and Expression Analysis of One Gamma-Glutamylcysteine Synthetase Gene (Hbγ-ECS1) in Latex Production in Hevea brasiliensis.

    PubMed

    Fang, Wei; Qiao, Luo Shi; Ming, Wu; Jian, Qiu; Feng, Yang Wen; Hua, Gao Hong; Zhou, Xiao Xian

    2016-01-01

    Rubber tree is a major commercial source of natural rubber. Latex coagulation is delayed by thiols, which belong to the important type of antioxidants in laticifer submembrane, and is composed of glutathione (GSH), cysteine, and methionine. The rate-limiting enzyme, γ-ECS, plays an important role in regulating the biosynthesis of glutathione under any environment conditions. To understand the relation between γ-ECS and thiols and to correlate latex flow with one-time tapping and continuous tapping, we cloned and derived the full length of one γ-ECS from rubber tree latex (Hbγ-ECS1). According to qPCR analysis, the expression levels of Hbγ-ECS1 were induced by tapping and Ethrel stimulation, and the expression was related to thiols content in the latex. Continuous tapping induced injury, and the expression of HbγECS1 increased with routine tapping and Ethrel-stimulation tapping (more intensive tapping). According to expression in long-term flowing latex, the gene was related to the duration of latex flow. HbγECS1 was expressed in E. coli Rosetta using pET-sumo as an expression vector and the recombinant enzyme was purified; then we achieved 0.827 U/mg specific activity and about 66 kDa molecular weight. The present study can help us understand the complex role of Hbγ-ECS in thiols biosynthesis, which is influenced by tapping.

  7. Transcriptome sequencing of Hevea brasiliensis for development of microsatellite markers and construction of a genetic linkage map.

    PubMed

    Triwitayakorn, Kanokporn; Chatkulkawin, Pornsupa; Kanjanawattanawong, Supanath; Sraphet, Supajit; Yoocha, Thippawan; Sangsrakru, Duangjai; Chanprasert, Juntima; Ngamphiw, Chumpol; Jomchai, Nukoon; Therawattanasuk, Kanikar; Tangphatsornruang, Sithichoke

    2011-12-01

    To obtain more information on the Hevea brasiliensis genome, we sequenced the transcriptome from the vegetative shoot apex yielding 2 311 497 reads. Clustering and assembly of the reads produced a total of 113 313 unique sequences, comprising 28 387 isotigs and 84 926 singletons. Also, 17 819 expressed sequence tag (EST)-simple sequence repeats (SSRs) were identified from the data set. To demonstrate the use of this EST resource for marker development, primers were designed for 430 of the EST-SSRs. Three hundred and twenty-three primer pairs were amplifiable in H. brasiliensis clones. Polymorphic information content values of selected 47 SSRs among 20 H. brasiliensis clones ranged from 0.13 to 0.71, with an average of 0.51. A dendrogram of genetic similarities between the 20 H. brasiliensis clones using these 47 EST-SSRs suggested two distinct groups that correlated well with clone pedigree. These novel EST-SSRs together with the published SSRs were used for the construction of an integrated parental linkage map of H. brasiliensis based on 81 lines of an F1 mapping population. The map consisted of 97 loci, consisting of 37 novel EST-SSRs and 60 published SSRs, distributed on 23 linkage groups and covered 842.9 cM with a mean interval of 11.9 cM and ∼4 loci per linkage group. Although the numbers of linkage groups exceed the haploid number (18), but with several common markers between homologous linkage groups with the previous map indicated that the F1 map in this study is appropriate for further study in marker-assisted selection.

  8. Sucrose importation into laticifers of Hevea brasiliensis, in relation to ethylene stimulation of latex production

    PubMed Central

    Dusotoit-Coucaud, Anaïs; Brunel, Nicole; Kongsawadworakul, Panida; Viboonjun, Unchera; Lacointe, André; Julien, Jean-Louis; Chrestin, Hervé; Sakr, Soulaïman

    2009-01-01

    Background and Aims The major economic product of Hevea brasiliensis is a rubber-containing cytoplasm (latex), which flows out of laticifers (latex cells) when the bark is tapped. The latex yield is stimulated by ethylene. Sucrose, the unique precursor of rubber synthesis, must cross the plasma membrane through specific sucrose transporters before being metabolized in the laticifers. The relative importance of sucrose transporters in determining latex yield is unknown. Here, the effects of ethylene (by application of Ethrel®) on sucrose transporter gene expression in the inner bark tissues and latex cells of H. brasiliensis are described. Methods Experiments, including cloning sucrose transporters, real time RT-PCR and in situ hybridization, were carried out on virgin (untapped) trees, treated or untreated with the latex yield stimulant Ethrel. Key Results Seven putative full-length cDNAs of sucrose transporters were cloned from a latex-specific cDNA library. These transporters belong to all SUT (sucrose transporter) groups and differ by their basal gene expression in latex and inner soft bark, with a predominance of HbSUT1A and HbSUT1B. Of these sucrose transporters, only HbSUT1A and HbSUT2A were distinctly increased by ethylene. Moreover, this increase was shown to be specific to laticifers and to ethylene application. Conclusion The data and all previous information on sucrose transport show that HbSUT1A and HbSUT2A are related to the increase in sucrose import into laticifers, required for the stimulation of latex yield by ethylene in virgin trees. PMID:19567416

  9. Identification of laticifer-specific genes and their promoter regions from a natural rubber producing plant Hevea brasiliensis.

    PubMed

    Aoki, Yuichi; Takahashi, Seiji; Takayama, Daisuke; Ogata, Yoshiyuki; Sakurai, Nozomu; Suzuki, Hideyuki; Asawatreratanakul, Kasem; Wititsuwannakul, Dhirayos; Wititsuwannakul, Rapepun; Shibata, Daisuke; Koyama, Tanetoshi; Nakayama, Toru

    2014-08-01

    Latex, the milky cytoplasm of highly differentiated cells called laticifers, from Hevea brasiliensis is a key source of commercial natural rubber production. One way to enhance natural rubber production would be to express genes involved in natural rubber biosynthesis by a laticifer-specific overexpression system. As a first step to identify promoters which could regulate the laticifer-specific expression, we identified random clones from a cDNA library of H. brasiliensis latex, resulting in 4325 expressed sequence tags (ESTs) assembled into 1308 unigenes (692 contigs and 617 singletons). Quantitative analyses of the transcription levels of high redundancy clones in the ESTs revealed genes highly and predominantly expressed in laticifers, such as Rubber Elongation Factor (REF), Small Rubber Particle Protein and putative protease inhibitor proteins. HRT1 and HRT2, cis-prenyltransferases involved in rubber biosynthesis, was also expressed predominantly in laticifers, although these transcript levels were 80-fold lower than that of REF. The 5'-upstream regions of these laticifer-specific genes were cloned and analyzed in silico, revealing seven common motifs consisting of eight bases. Furthermore, transcription factors specifically expressed in laticifers were also identified. The common motifs in the laticifer-specific genes and the laticifer-specific transcription factors are potentially involved in the regulation of gene expression in laticifers.

  10. Identification of the Hevea brasiliensis AP2/ERF superfamily by RNA sequencing

    PubMed Central

    2013-01-01

    Background Rubber tree (Hevea brasiliensis) laticifers are the source of natural rubber. Rubber production depends on endogenous and exogenous ethylene (ethephon). AP2/ERF transcription factors, and especially Ethylene-Response Factors, play a crucial role in plant development and response to biotic and abiotic stresses. This study set out to sequence transcript expressed in various tissues using next-generation sequencing and to identify AP2/ERF superfamily in the rubber tree. Results The 454 sequencing technique was used to produce five tissue-type transcript libraries (leaf, bark, latex, embryogenic tissues and root). Reads from all libraries were pooled and reassembled to improve mRNA lengths and produce a global library. One hundred and seventy-three AP2/ERF contigs were identified by in silico analysis based on the amino acid sequence of the conserved AP2 domain from the global library. The 142 contigs with the full AP2 domain were classified into three main families (20 AP2 members, 115 ERF members divided into 11 groups, and 4 RAV members) and 3 soloist members. Fifty-nine AP2/ERF transcripts were found in latex. Alongside the microRNA172 already described in plants, eleven additional microRNAs were predicted to inhibit Hevea AP2/ERF transcripts. Conclusions Hevea has a similar number of AP2/ERF genes to that of other dicot species. We adapted the alignment and classification methods to data from next-generation sequencing techniques to provide reliable information. We observed several specific features for the ERF family. Three HbSoloist members form a group in Hevea. Several AP2/ERF genes highly expressed in latex suggest they have a specific function in Hevea. The analysis of AP2/ERF transcripts in Hevea presented here provides the basis for studying the molecular regulation of latex production in response to abiotic stresses and latex cell differentiation. PMID:23324139

  11. Sequence and Expression Analyses of Ethylene Response Factors Highly Expressed in Latex Cells from Hevea brasiliensis

    PubMed Central

    Piyatrakul, Piyanuch; Yang, Meng; Putranto, Riza-Arief; Pirrello, Julien; Dessailly, Florence; Hu, Songnian; Summo, Marilyne; Theeravatanasuk, Kannikar; Leclercq, Julie; Kuswanhadi; Montoro, Pascal

    2014-01-01

    The AP2/ERF superfamily encodes transcription factors that play a key role in plant development and responses to abiotic and biotic stress. In Hevea brasiliensis, ERF genes have been identified by RNA sequencing. This study set out to validate the number of HbERF genes, and identify ERF genes involved in the regulation of latex cell metabolism. A comprehensive Hevea transcriptome was improved using additional RNA reads from reproductive tissues. Newly assembled contigs were annotated in the Gene Ontology database and were assigned to 3 main categories. The AP2/ERF superfamily is the third most represented compared with other transcription factor families. A comparison with genomic scaffolds led to an estimation of 114 AP2/ERF genes and 1 soloist in Hevea brasiliensis. Based on a phylogenetic analysis, functions were predicted for 26 HbERF genes. A relative transcript abundance analysis was performed by real-time RT-PCR in various tissues. Transcripts of ERFs from group I and VIII were very abundant in all tissues while those of group VII were highly accumulated in latex cells. Seven of the thirty-five ERF expression marker genes were highly expressed in latex. Subcellular localization and transactivation analyses suggested that HbERF-VII candidate genes encoded functional transcription factors. PMID:24971876

  12. Systemic Identification of Hevea brasiliensis EST-SSR Markers and Primer Screening

    PubMed Central

    Hou, Benjun

    2017-01-01

    This research aimed to systematically identify and preliminarily validate the Hevea brasiliensis expressed sequence tag (EST) information using Simple Sequence Repeat (SSR) and provide evidence for further development of SSR molecular marker. The definition of general SSR features of Hevea EST splicing sequences and development of SSR primers founded the basis of diversity analysis and variety identification for Hevea tree resource. 1134 SSR loci were identified in the EST splicing sequence and distributed in 840 Unigene. The occurrence rate of SSR loci was 23.9%, and the average distribution distance of EST-SSR was 2.59 kb. The major repeat type was mononucleotide repeat motif, which accounted for 38.89%, while the corresponding value was 36.95% for dinucleotide repeat motif and 18.17% for trinucleotide repeat motif; the proportion of other motifs was only 5.99%. The superior repeat motifs for mononucleotide, dinucleotide, and trinucleotide were A/T, AG/CT, and AAG/CTT, respectively. 739 pair of primers were designed for 1134 SSR loci. PCR amplification was performed on Hevea Reyan5-11, Reyan87-6-47, and PR107, and 180 pairs of primers were selected which were able to amplify polymorphism bands. PMID:28232872

  13. Wound-induced accumulation of mRNA containing a hevein sequence in laticifers of rubber tree (Hevea brasiliensis).

    PubMed Central

    Broekaert, I; Lee, H I; Kush, A; Chua, N H; Raikhel, N

    1990-01-01

    Hevein is a chitin-binding protein that is present in laticifers of the rubber tree (Hevea brasiliensis). A cDNA clone (HEV1) encoding hevein was isolated by using the polymerase chain reaction with mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea latex cDNA library as a template. HEV1 is 1018 base pairs long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187-amino acid polypeptide. This polypeptide has two striking features. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino termini of wound-inducible proteins in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74-79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems, and latex but not in roots. Images PMID:2217194

  14. Physiological and Molecular Responses to Variation of Light Intensity in Rubber Tree (Hevea brasiliensis Muell. Arg.)

    PubMed Central

    Wang, Li-feng

    2014-01-01

    Light is one of most important factors to plants because it is necessary for photosynthesis. In this study, physiological and gene expression analyses under different light intensities were performed in the seedlings of rubber tree (Hevea brasiliensis) clone GT1. When light intensity increased from 20 to 1000 µmol m−2 s−1, there was no effect on the maximal quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), indicating that high light intensity did not damage the structure and function of PSII reaction center. However, the effective photochemical quantum yield of PSII (Y(II)), photochemical quenching coefficient (qP), electron transfer rate (ETR), and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae (qL) were increased significantly as the light intensity increased, reached a maximum at 200 µmol m−2 s−1, but decreased from 400 µmol m−2 s−1. These results suggested that the PSII photochemistry showed an optimum performance at 200 µmol m−2 s−1 light intensity. The chlorophyll content was increased along with the increase of light intensity when it was no more than 400 µmol m−2 s−1. Since increasing light intensity caused significant increase in H2O2 content and decreases in the per unit activity of antioxidant enzymes SOD and POD, but the malondialdehyde (MDA) content was preserved at a low level even under high light intensity of 1000 µmol m−2 s−1, suggesting that high light irradiation did not induce membrane lipid peroxidation in rubber tree. Moreover, expressions of antioxidant-related genes were significantly up-regulated with the increase of light intensity. They reached the maximum expression at 400 µmol m−2 s−1, but decreased at 1000 µmol m−2 s−1. In conclusion, rubber tree could endure strong light irradiation via a specific mechanism. Adaptation to high light intensity is a complex process by regulating antioxidant enzymes activities, chloroplast formation, and

  15. Physiological and molecular responses to variation of light intensity in rubber Tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Wang, Li-feng

    2014-01-01

    Light is one of most important factors to plants because it is necessary for photosynthesis. In this study, physiological and gene expression analyses under different light intensities were performed in the seedlings of rubber tree (Hevea brasiliensis) clone GT1. When light intensity increased from 20 to 1000 µmol m(-2) s(-1), there was no effect on the maximal quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), indicating that high light intensity did not damage the structure and function of PSII reaction center. However, the effective photochemical quantum yield of PSII (Y(II)), photochemical quenching coefficient (qP), electron transfer rate (ETR), and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae (qL) were increased significantly as the light intensity increased, reached a maximum at 200 µmol m(-2) s(-1), but decreased from 400 µmol m(-2) s(-1). These results suggested that the PSII photochemistry showed an optimum performance at 200 µmol m(-2) s(-1) light intensity. The chlorophyll content was increased along with the increase of light intensity when it was no more than 400 µmol m(-2) s(-1). Since increasing light intensity caused significant increase in H2O2 content and decreases in the per unit activity of antioxidant enzymes SOD and POD, but the malondialdehyde (MDA) content was preserved at a low level even under high light intensity of 1000 µmol m(-2) s(-1), suggesting that high light irradiation did not induce membrane lipid peroxidation in rubber tree. Moreover, expressions of antioxidant-related genes were significantly up-regulated with the increase of light intensity. They reached the maximum expression at 400 µmol m(-2) s(-1), but decreased at 1000 µmol m(-2) s(-1). In conclusion, rubber tree could endure strong light irradiation via a specific mechanism. Adaptation to high light intensity is a complex process by regulating antioxidant enzymes activities, chloroplast formation, and

  16. Sugar metabolism and developmental stages of rubber tree (Hevea brasiliensis L.) seeds.

    PubMed

    de Souza, Genaina Aparecida; Dias, Denise Cunha Fernandes Dos Santos; Pimenta, Thaline Martins; Almeida, Andrea Lanna; Picoli, Edgard Augusto de Toledo; Alvarenga, Antônio de Pádua; da Silva, José Cleydson Ferreira

    2017-10-09

    Changes in the concentration of sugars and sucrose metabolism enzymes can characterize the developmental stages of a seed. In recalcitrant species such as Hevea brasiliensis L., little is known about these changes. We aimed to evaluate the three main stages of development of rubber tree seeds - histodifferentiation, cell elongation and accumulation of reserves. The activities of acid and neutral invertases (E.C. 3.2.1.26) and sucrose synthase (EC 2.4.1.13), and the concentrations of reducing sugars (RS), total soluble sugars (TSS), and sucrose (Suc) were determined concomitantly with the histochemical and anatomical evaluation of seed structure. Histodifferentiation in rubber tree seeds occurs up to 75 days after anthesis (DAA). The concentration of RS is high and of Suc is low during seed histodifferentiation, which occurs along with a visible increase in the number of cell divisions. After that period, there is an increase in the concentration of Suc (mg g(-1) ) and in the number and size of starch granules, and a decrease in the concentration of RS (mg g(-1) ). At that point, cell elongation occurs. At 135 DAA, there is an inversion in the concentration of these two sugars and an increase in reserve accumulation. Thus, in seeds of the evaluated clone, the period up to 75 DAA is characterized as the histodifferentiation stage, while from that time up to 120 DAA the cell elongation stage takes place. The final stage of seed maturation and reserve accumulation begins at 135 DAA, and the seed, including the embryo, is completely formed at 175 DAA. This article is protected by copyright. All rights reserved.

  17. Enzymatic synthesis of rubber polymer in Hevea brasiliensis

    SciTech Connect

    Tang, F.; Hu, S.; Benedict, C.R. )

    1991-05-01

    Light and Dennis purified serum soluble rubber transferase from Hevea latex to homogeneity. Prenyl transferase co-purified with rubber transferase. In the absence of washed rubber particles (WRP) the prenyl transferase catalyzed the formation of trans FPP from DMAPP and IPP. In the presence of WRP the transferase catalyzed cis additions of IPP to pre-existing rubber chains. Control mixtures of WRP, Mg{sup 2+} and FPP were not included to test for the contributions of the bound rubber transferase on WRP to the incorporation of IPP into polyisoprene. Bound rubber transferase catalyzes the repetitive addition of IPP to allylic-PP starter molecules to form polyisoprene. The order of utilization of allylic-PP starters was GGPP > FPP > GPP > DMAPP. The authors have shown that the polyisoprene enzymatically synthesized on WRP is a bimodal polymer consisting of different mol wt rubber chains similar to the polymeric characteristics of natural rubber. The bound rubber transferase was solubilized with Chaps and purified on DEAE-cellulose. The polymerization reaction catalyzed by the purified preparation showed a 98% requirement for pre-existing rubber chains. Results suggest that the prenyl transferase from Hevea serum may be part of the polymer starter system furnishing allylic-PP for the bound rubber transferase.

  18. [Soil moisture content and fine root biomass of rubber tree (Hevea brasiliensis) plantations at different ages].

    PubMed

    Lin, Xi-Hao; Chen, Qiu-Bo; Hua, Yuan-Gang; Yang, Li-Fu; Wang, Zhen-Hui

    2011-02-01

    By using soil core sampling method, this paper studied the soil moisture regime of rubber plantations and the fine root biomass of Hevea brasiliensis in immature period (5 a), early yielding period (9 a), and peak yielding period (16 a). With the increasing age of rubber trees, the soil moisture content of rubber plantations increased but the fine root biomass decreased. The soil moisture content at the depth of 0-60 cm in test rubber plantations increased with soil depth, and presented a double-peak pattern over the period of one year. The fine root biomass of rubber trees at different ages had the maximum value in the top 10 cm soil layers and decreased with soil depth, its seasonal variation also showed a double-peak pattern, but the peak values appeared at different time. Soil moisture content and soil depth were the main factors affecting the fine root biomass of H. brasiliensis.

  19. The micromorphology and protein characterization of rubber particles in Ficus carica, Ficus benghalensis and Hevea brasiliensis.

    PubMed

    Singh, Adya P; Wi, Seung Gon; Chung, Gap Chae; Kim, Yoon Soo; Kang, Hunseung

    2003-03-01

    Rubber biosynthesis takes place on the surface of rubber particles. These particles are surrounded by a monolayer membrane in which the rubber transferase is anchored. In order to gain better insight into whether rubber particles from different plant species share common structural characteristics, the micromorphology of rubber particles from Ficus carica, Ficus benghalensis, and Hevea brasiliensis was examined by electron microscopy. Rubber particles of all three species were spherical in shape, and the size of rubber particles of H. brasiliensis was much smaller than those of F. carica and F. benghalensis. In addition, investigations were undertaken to compare the cross-reactivity of the antibody raised against either the H. brasiliensis small rubber particle protein (SRPP) which is suggested to be involved in rubber biosynthesis, or the cis-prenyltransferase (CPT) which has an activity similar to rubber transferase. Both western analysis and TEM-immunogold labelling studies showed that rubber particles of F. carica and F. benghalensis do not contain the SRPP. None of the rubber particles in F. carica, F. benghalensis and H. brasiliensis contained the CPT, suggesting that the CPT itself could not catalyse the formation of high molecular weight rubber. These results indicate that rubber particles in the three different plant species investigated share some degree of similarity in architecture, and that the SRPP and CPT themselves are not the core proteins necessary for rubber biosynthesis.

  20. Neofusicoccum ribis Associated with Leaf Blight on Rubber (Hevea brasiliensis) in Peninsular Malaysia

    PubMed Central

    Nyaka Ngobisa, A. I. C.; Zainal Abidin, M. A.; Wong, M. Y.; Wan Noordin, M. W. D.

    2013-01-01

    Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations – Selangor, Perak, and Johor states – in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis. PMID:25288924

  1. Identification of novel microRNAs in Hevea brasiliensis and computational prediction of their targets

    PubMed Central

    2012-01-01

    Background Plants respond to external stimuli through fine regulation of gene expression partially ensured by small RNAs. Of these, microRNAs (miRNAs) play a crucial role. They negatively regulate gene expression by targeting the cleavage or translational inhibition of target messenger RNAs (mRNAs). In Hevea brasiliensis, environmental and harvesting stresses are known to affect natural rubber production. This study set out to identify abiotic stress-related miRNAs in Hevea using next-generation sequencing and bioinformatic analysis. Results Deep sequencing of small RNAs was carried out on plantlets subjected to severe abiotic stress using the Solexa technique. By combining the LeARN pipeline, data from the Plant microRNA database (PMRD) and Hevea EST sequences, we identified 48 conserved miRNA families already characterized in other plant species, and 10 putatively novel miRNA families. The results showed the most abundant size for miRNAs to be 24 nucleotides, except for seven families. Several MIR genes produced both 20-22 nucleotides and 23-27 nucleotides. The two miRNA class sizes were detected for both conserved and putative novel miRNA families, suggesting their functional duality. The EST databases were scanned with conserved and novel miRNA sequences. MiRNA targets were computationally predicted and analysed. The predicted targets involved in "responses to stimuli" and to "antioxidant" and "transcription activities" are presented. Conclusions Deep sequencing of small RNAs combined with transcriptomic data is a powerful tool for identifying conserved and novel miRNAs when the complete genome is not yet available. Our study provided additional information for evolutionary studies and revealed potentially specific regulation of the control of redox status in Hevea. PMID:22330773

  2. Genome-wide analysis of microRNAs in rubber tree (Hevea brasiliensis L.) using high-throughput sequencing.

    PubMed

    Lertpanyasampatha, Manassawe; Gao, Lei; Kongsawadworakul, Panida; Viboonjun, Unchera; Chrestin, Hervé; Liu, Renyi; Chen, Xuemei; Narangajavana, Jarunya

    2012-08-01

    MicroRNAs (miRNAs) are short RNAs with essential roles in gene regulation in various organisms including higher plants. In contrast to the vast information on miRNAs from many economically important plants, almost nothing has been reported on the identification or analysis of miRNAs from rubber tree (Hevea brasiliensis L.), the most important natural rubber-producing crop. To identify miRNAs and their target genes in rubber tree, high-throughput sequencing combined with a computational approach was performed. Four small RNA libraries were constructed for deep sequencing from mature and young leaves of two rubber tree clones, PB 260 and PB 217, which provide high and low latex yield, respectively. 115 miRNAs belonging to 56 known miRNA families were identified, and northern hybridization validated miRNA expression and revealed developmental stage-dependent and clone-specific expression for some miRNAs. We took advantage of the newly released rubber tree genome assembly and predicted 20 novel miRNAs. Further, computational analysis uncovered potential targets of the known and novel miRNAs. Predicted target genes included not only transcription factors but also genes involved in various biological processes including stress responses, primary and secondary metabolism, and signal transduction. In particular, genes with roles in rubber biosynthesis are predicted targets of miRNAs. This study provides a basic catalog of miRNAs and their targets in rubber tree to facilitate future improvement and exploitation of rubber tree.

  3. Identification and functional characterization of HbOsmotin from Hevea brasiliensis.

    PubMed

    Tong, Zheng; Sun, Yong; Wang, Dan; Wang, Limin; Li, Ling; Meng, Xueru; Feng, Weiqiang; Wurtele, Eve Syrkin; Wang, Xuchu

    2016-12-01

    Latex in the laticiferous cell network of Hevea brasiliensis tree is composed of cytoplasm that synthesizes natural rubber. Ethylene stimulation of the tree bark enhances latex production partly by prolonging the duration of latex flow during the tapping process. Here, we identified an osmotin-like cDNA sequence (HbOsmotin) from H. brasiliensis that belongs to the pathogenesis-related 5 (PR-5) gene family. The HbOsmotin protein is present in the lutoids of latex in H. brasiliensis, whereas in onion epidermal cells, this protein is predominantly distributed around the cell wall, suggesting that it may be secreted from the cytoplasm. We investigated the effects of exogenous ethylene on HbOsmotin transcription and protein accumulation in rubber latex, and further determined the protein function after osmotic stress in Arabidopsis. In regularly tapped trees, HbOsmotin expression was drastically inhibited in rubber latex after tapping, although the expression was subsequently recovered by ethylene stimulation. However, in virgin plants that had never been tapped, exogenous ethylene application slightly decreased HbOsmotin expression. HbOsmotin overexpression in Arabidopsis showed that HbOsmotin reduced the osmotic stress tolerance of the plant, which likely occurred by raising the water potential. These data indicated that HbOsmotin may contribute to osmotic regulation in laticiferous cells.

  4. RNA sequencing read depth requirement for optimal transcriptome coverage in Hevea brasiliensis

    PubMed Central

    2014-01-01

    Background One of the concerns of assembling de novo transcriptomes is determining the amount of read sequences required to ensure a comprehensive coverage of genes expressed in a particular sample. In this report, we describe the use of Illumina paired-end RNA-Seq (PE RNA-Seq) reads from Hevea brasiliensis (rubber tree) bark to devise a transcript mapping approach for the estimation of the read amount needed for deep transcriptome coverage. Findings We optimized the assembly of a Hevea bark transcriptome based on 16 Gb Illumina PE RNA-Seq reads using the Oases assembler across a range of k-mer sizes. We then assessed assembly quality based on transcript N50 length and transcript mapping statistics in relation to (a) known Hevea cDNAs with complete open reading frames, (b) a set of core eukaryotic genes and (c) Hevea genome scaffolds. This was followed by a systematic transcript mapping process where sub-assemblies from a series of incremental amounts of bark transcripts were aligned to transcripts from the entire bark transcriptome assembly. The exercise served to relate read amounts to the degree of transcript mapping level, the latter being an indicator of the coverage of gene transcripts expressed in the sample. As read amounts or datasize increased toward 16 Gb, the number of transcripts mapped to the entire bark assembly approached saturation. A colour matrix was subsequently generated to illustrate sequencing depth requirement in relation to the degree of coverage of total sample transcripts. Conclusions We devised a procedure, the “transcript mapping saturation test”, to estimate the amount of RNA-Seq reads needed for deep coverage of transcriptomes. For Hevea de novo assembly, we propose generating between 5–8 Gb reads, whereby around 90% transcript coverage could be achieved with optimized k-mers and transcript N50 length. The principle behind this methodology may also be applied to other non-model plants, or with reads from other second generation

  5. Ethylene stimulation of latex yield depends on the expression of a sucrose transporter (HbSUT1B) in rubber tree (Hevea brasiliensis).

    PubMed

    Dusotoit-Coucaud, Anaïs; Kongsawadworakul, Panida; Maurousset, Laurence; Viboonjun, Unshira; Brunel, Nicole; Pujade-Renaud, Valérie; Chrestin, Hervé; Sakr, Soulaïman

    2010-12-01

    Hevea brasiliensis is an important industrial crop for natural rubber production. Latex biosynthesis occurs in the cytoplasm of highly specialized latex cells and requires sucrose as the unique precursor. Ethylene stimulation of latex production results in high sugar flow from the surrounding cells of inner bark towards the latex cells. The aim of this work was to understand the role of seven sucrose transporters (HbSUTs) and one hexose transporter (HbHXT1) in this process. Two Hevea clones were used: PB217 and PB260, respectively described as high and low yielding clones. The expression pattern of these sugar transporters (HbSUTs and HbHXT1) was monitored under different physiological conditions and found to be maximal in latex cells. HbSUT1, one of the most abundant isoforms, displayed the greatest response to ethylene treatment. In clone PB217, ethylene treatment led to a higher accumulation of HbSUT1B in latex cells than in the inner bark tissues. Conversely, stronger expression of HbSUT1B was observed in inner bark tissues than in latex cells of PB260. A positive correlation with HbSUT1B transcript accumulation and increased latex production was further supported by its lower expression in latex cells of the virgin clone PB217.

  6. The small RNA profile in latex from Hevea brasiliensis trees is affected by tapping panel dryness.

    PubMed

    Gébelin, Virginie; Leclercq, Julie; Kuswanhadi; Argout, Xavier; Chaidamsari, Tetty; Hu, Songnian; Tang, Chaorong; Sarah, Gautier; Yang, Meng; Montoro, Pascal

    2013-10-01

    Natural rubber is harvested by tapping Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg. Harvesting stress can lead to tapping panel dryness (TPD). MicroRNAs (miRNAs) are induced by abiotic stress and regulate gene expression by targeting the cleavage or translational inhibition of target messenger RNAs. This study set out to sequence miRNAs expressed in latex cells and to identify TPD-related putative targets. Deep sequencing of small RNAs was carried out on latex from trees affected by TPD using Solexa technology. The most abundant small RNA class size was 21 nucleotides for TPD trees compared with 24 nucleotides in healthy trees. By combining the LeARN pipeline, data from the Plant MicroRNA database and Hevea EST sequences, we identified 19 additional conserved and four putative species-specific miRNA families not found in previous studies on rubber. The relative transcript abundance of the Hbpre-MIR159b gene increased with TPD. This study revealed a small RNA-specific signature of TPD-affected trees. Both RNA degradation and a shift in miRNA biogenesis are suggested to explain the general decline in small RNAs and, particularly, in miRNAs.

  7. Reactive oxygen species in Hevea brasiliensis latex and relevance to Tapping Panel Dryness.

    PubMed

    Zhang, Yi; Leclercq, Julie; Montoro, Pascal

    2016-11-29

    Environmental stress can lead to oxidative stress resulting from an increase in reactive oxygen species (ROS) and involves redox adjustments. Natural rubber is synthesized in laticifers, which is a non-photosynthetic tissue particularly prone to oxidative stress. This paper reviews the current state of knowledge on the ROS production and ROS-scavenging systems in laticifers. These regulations have been the subject of intense research into a physiological syndrome, called Tapping Panel Dryness (TPD), affecting latex production in Hevea brasiliensis In order to prevent TPD occurrence, monitoring thiol content appeared to be a crucial factor of latex diagnosis. Thiols, ascorbate and γ-tocotrienol are the major antioxidants in latex. They are involved in membrane protection from ROS and likely have an effect on the quality of raw rubber. Some transcription factors might play a role in the redox regulatory network in Hevea, in particular ethylene response factors, which have been the most intensively studied given the role of ethylene on rubber production. Current challenges for rubber research and development with regard to redox systems will involve improving antioxidant capacity using natural genetic variability.

  8. Applications of volatile compounds acquired from Muscodor heveae against white root rot disease in rubber trees (Hevea brasiliensis Müll. Arg.) and relevant allelopathy effects.

    PubMed

    Siri-Udom, Sakuntala; Suwannarach, Nakarin; Lumyong, Saisamorn

    The bioactive compounds of the volatile metabolite-producing endophytic fungus, Muscodor heveae, were examined by the process of biofumigation for the purposes of controlling white root rot disease in rubber trees (Hevea brasiliensis Müll. Arg.). Volatile organic compounds (VOCs) of M. heveae possess antimicrobial activity against Rigidoporus microporus in vitro with 100 % growth inhibition. The synthetic volatile compounds test confirmed that the major component, 3-methylbutan-1-ol, and the minor compounds, 3-methylbutyl acetate and 2-methylpropanoic acid, inhibited root and shoot growth in the tested plants 3-methylbutan-1-ol showed ED50 value and MIQ value on seed germination of ruzi grass, Arabidopsis thaliana Col-0 and tomato at 10, 5 and 5 μL(-1) airspace, respectively. In vivo tests were carried out under greenhouse conditions using M. heveae inoculum fumigated soil that had been inoculated with R. microporus inoculum. After which, all seven treatments were compared. Significant differences were observed with a disease score at 150 d after treatment. Biofumigation by M. heveae showed great suppression of the disease. Biocontrol treatments; RMH40 (40 g kg(-1)M. heveae inoculum) and RMH80 (80 g kg(-1)M. heveae inoculum) were not found to be significantly different when compared with fungicide treatment (RT) and the non-infected control, but results were found to be significantly different from R. microporus infested (R) treatment. RMH40 and RMH80 revealed a low disease scores with a high survival rate of rubber tree seedling at 100 %, while R treatment showed the highest disease score of 4.8 ± 0.5 with a survival rate of rubber tree seedling at 25 %. The infected roots, appearing as a white colour. We have concluded that the bioactive VOCs of M. heveae would be an alternative method for the control of white root rot disease in rubber trees. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  9. Hevea brasiliensis REF (Hev b 1) and SRPP (Hev b 3): An overview on rubber particle proteins.

    PubMed

    Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Peruch, Frédéric

    2014-11-01

    This review article aims to gather all the knowledge on two important proteins associated with Hevea brasiliensis rubber particles: namely the rubber elongation factor (REF) and the small rubber particle protein (SRPP). It covers more then three decades of research on these two proteins and their homologues in plants, and particularly emphasizes on the different possible properties or functions of these various proteins found in plants.

  10. Green synthesis of colloidal silver nanoparticles using natural rubber latex extracted from Hevea brasiliensis.

    PubMed

    Guidelli, Eder José; Ramos, Ana Paula; Zaniquelli, Maria Elisabete D; Baffa, Oswaldo

    2011-11-01

    Colloidal silver nanoparticles were synthesized by an easy green method using thermal treatment of aqueous solutions of silver nitrate and natural rubber latex (NRL) extracted from Hevea brasiliensis. The UV-Vis spectra detected the characteristic surface plasmonic absorption band around 435 nm. Both NRL and AgNO(3) contents in the reaction medium have influence in the Ag nanoparticles formation. Lower AgNO(3) concentration led to decreased particle size. The silver nanoparticles presented diameters ranging from 2 nm to 100 nm and had spherical shape. The selected area electron diffraction (SAED) patterns indicated that the silver nanoparticles have face centered cubic (fcc) crystalline structure. FTIR spectra suggest that reduction of the silver ions are facilitated by their interaction with the amine groups from ammonia, which is used for conservation of the NRL, whereas the stability of the particles results from cis-isoprene binding onto the surface of nanoparticles. Therefore natural rubber latex extracted from H. brasiliensis can be employed in the preparation of stable aqueous dispersions of silver nanoparticles acting as a dispersing and/or capping agent. Moreover, this work provides a new method for the synthesis of silver nanoparticles that is simple, easy to perform, pollutant free and inexpensive.

  11. Green synthesis of colloidal silver nanoparticles using natural rubber latex extracted from Hevea brasiliensis

    NASA Astrophysics Data System (ADS)

    Guidelli, Eder José; Ramos, Ana Paula; Zaniquelli, Maria Elisabete D.; Baffa, Oswaldo

    2011-11-01

    Colloidal silver nanoparticles were synthesized by an easy green method using thermal treatment of aqueous solutions of silver nitrate and natural rubber latex (NRL) extracted from Hevea brasiliensis. The UV-Vis spectra detected the characteristic surface plasmonic absorption band around 435 nm. Both NRL and AgNO 3 contents in the reaction medium have influence in the Ag nanoparticles formation. Lower AgNO 3 concentration led to decreased particle size. The silver nanoparticles presented diameters ranging from 2 nm to 100 nm and had spherical shape. The selected area electron diffraction (SAED) patterns indicated that the silver nanoparticles have face centered cubic (fcc) crystalline structure. FTIR spectra suggest that reduction of the silver ions are facilitated by their interaction with the amine groups from ammonia, which is used for conservation of the NRL, whereas the stability of the particles results from cis-isoprene binding onto the surface of nanoparticles. Therefore natural rubber latex extracted from H. brasiliensis can be employed in the preparation of stable aqueous dispersions of silver nanoparticles acting as a dispersing and/or capping agent. Moreover, this work provides a new method for the synthesis of silver nanoparticles that is simple, easy to perform, pollutant free and inexpensive.

  12. Identification and characterization of MAGO and Y14 genes in Hevea brasiliensis

    PubMed Central

    Yang, Zi-Ping; Li, Hui-Liang; Guo, Dong; Peng, Shi-Qing

    2016-01-01

    Abstract Mago nashi (MAGO) and Y14 proteins are highly conserved among eukaryotes. In this study, we identified two MAGO (designated as HbMAGO1 andHbMAGO2) and two Y14 (designated as HbY14aand HbY14b) genes in the rubber tree (Hevea brasiliensis) genome annotation. Multiple amino acid sequence alignments predicted that HbMAGO and HbY14 proteins are structurally similar to homologous proteins from other species. Tissue-specific expression profiles showed that HbMAGO and HbY14 genes were expressed in at least one of the tissues (bark, flower, latex, leaf and root) examined. HbMAGOs and HbY14s were predominately located in the nucleus and were found to interact in yeast two-hybrid analysis (YTH) and bimolecular fluorescence complementation (BiFC) assays. HbMAGOs and HbY14s showed the highest transcription in latex and were regulated by ethylene and jasmonate. Interaction between HbMAGO2 and gp91phox (a large subunit of nicotinamide adenine dinucleotide phosphate) was identified using YTH and BiFC assays. These findings suggested that HbMAGO may be involved in the aggregation of rubber particles in H. brasiliensis. PMID:27007901

  13. The biosynthesis of rubber from β-hydroxy-β-methylglutaryl-coenzyme A in Hevea brasiliensis latex

    PubMed Central

    Hepper, C. M.; Audley, B. G.

    1969-01-01

    1. β-Hydroxy-β-methyl[3-14C]glutaryl-CoA is efficiently incorporated into rubber on incubation with Hevea brasiliensis latex, and the incorporation is diminished in the presence of unlabelled mevalonate. β-Hydroxy-β-methylglutaric acid is not utilized for rubber synthesis, but inhibits the formation of rubber from β-hydroxy-β-methylglutaryl-CoA. 2. The incorporation of β-hydroxy-β-methylglutaryl-CoA into rubber is stimulated equally by NADP+ and NADPH and less so by NAD+ and NADH. ATP is slightly stimulatory and CoA is inhibitory. 3. β-Hydroxy-β-methylglutaryl-CoA reductase is concentrated in the sediment (bottom fraction) formed by centrifuging latex at low speed and the enzyme is unstable in the absence of cysteine or GSH. The formation of NADPH takes place in the latex serum. 4. There is a marked seasonal variation in the extent of β-hydroxy-β-methylglutaryl-CoA incorporation into rubber in latex, but mevalonate incorporation is relatively constant. This observation, together with the finding that β-hydroxy-β-methylglutaryl-CoA reduction is the rate-limiting step in the formation of rubber from β-hydroxy-β-methylglutaryl-CoA, suggests that the conversion of β-hydroxy-β-methylglutaryl-CoA into mevalonate is of importance in the regulation of rubber synthesis. 5. Evidence suggesting that β-hydroxy-β-methylglutaryl-CoA lyase is present in H. brasiliensis latex has been obtained. PMID:4390212

  14. Comparative proteome analysis of rubber latex serum from pathogenic fungi tolerant and susceptible rubber tree (Hevea brasiliensis).

    PubMed

    Havanapan, Phattara-Orn; Bourchookarn, Apichai; Ketterman, Albert J; Krittanai, Chartchai

    2016-01-10

    Many cultivated rubber trees (Hevea brasiliensis) are invaded by various Phytophthora species fungi, especially in tropical regions which result in crop yield losses. Comparative proteome analysis coupled with liquid chromatography electrospray/ionization (LC-ESI) mass spectrometry identification was employed to investigate the relative abundance of defense related proteins in Phytophthora sp. susceptible (RRIM600) and tolerant (BPM24) clones of rubber tree. Proteome maps of non-rubber constituent of these two model clones show similar protein counts, although some proteins show significant alterations in their abundance. Most of the differentially abundant proteins found in the serum of BPM24 illustrate the accumulation of defense related proteins that participate in plant defense mechanisms such as beta-1,3-glucanase, chitinase, and lectin. SDS-PAGE and 2-D Western blot analysis showed greater level of accumulation of beta-1,3-glucanase and chitinase in latex serum of BPM24 when compared to RRIM600. A functional study of these two enzymes showed that BPM24 serum had greater beta-1,3-glucanase and chitinase activities than that of RRIM600. These up-regulated proteins are constitutively expressed and would serve to protect the rubber tree BPM24 from any fungal invader. The information obtained from this work is valuable for understanding of defense mechanisms and plantation improvement of H. brasiliensis. Non-rubber constituents (latex serum) have almost no value and are treated as waste in the rubber agricultural industry. However, the serum of natural rubber latex contains biochemical substances. The comparative proteomics analysis of latex serum between tolerant and susceptible clones reveals that the tolerant BPM24 clone contained a high abundance of several classes of fungal pathogen-responsive proteins, such as glucanase and chitinase. Moreover, other proteins identified highlighted the accumulation of defensive-associated proteins participating in plant

  15. In-depth proteome analysis of the rubber particle of Hevea brasiliensis (para rubber tree).

    PubMed

    Dai, Longjun; Kang, Guijuan; Li, Yu; Nie, Zhiyi; Duan, Cuifang; Zeng, Rizhong

    2013-05-01

    The rubber particle is a special organelle in which natural rubber is synthesised and stored in the laticifers of Hevea brasiliensis. To better understand the biological functions of rubber particles and to identify the candidate rubber biosynthesis-related proteins, a comprehensive proteome analysis was performed on H. brasiliensis rubber particles using shotgun tandem mass spectrometry profiling approaches-resulting in a thorough report on the rubber particle proteins. A total of 186 rubber particle proteins were identified, with a range in relative molecular mass of 3.9-194.2 kDa and in isoelectric point values of 4.0-11.2. The rubber particle proteins were analysed for gene ontology and could be categorised into eight major groups according to their functions: including rubber biosynthesis, stress- or defence-related responses, protein processing and folding, signal transduction and cellular transport. In addition to well-known rubber biosynthesis-related proteins such as rubber elongation factor (REF), small rubber particle protein (SRPP) and cis-prenyl transferase (CPT), many proteins were firstly identified to be on the rubber particles, including cyclophilin, phospholipase D, cytochrome P450, small GTP-binding protein, clathrin, eukaryotic translation initiation factor, annexin, ABC transporter, translationally controlled tumour protein, ubiquitin-conjugating enzymes, and several homologues of REF, SRPP and CPT. A procedure of multiple reaction monitoring was established for further protein validation. This comprehensive proteome data of rubber particles would facilitate investigation into molecular mechanisms of biogenesis, self-homeostasis and rubber biosynthesis of the rubber particle, and might serve as valuable biomarkers in molecular breeding studies of H. brasiliensis and other alternative rubber-producing species.

  16. Ethylene Response Factors Are Controlled by Multiple Harvesting Stresses in Hevea brasiliensis.

    PubMed

    Putranto, Riza-Arief; Duan, Cuifang; Kuswanhadi; Chaidamsari, Tetty; Rio, Maryannick; Piyatrakul, Piyanuch; Herlinawati, Eva; Pirrello, Julien; Dessailly, Florence; Leclercq, Julie; Bonnot, François; Tang, Chaorong; Hu, Songnian; Montoro, Pascal

    2015-01-01

    Tolerance of recurrent mechanical wounding and exogenous ethylene is a feature of the rubber tree. Latex harvesting involves tapping of the tree bark and ethephon is applied to increase latex flow. Ethylene is an essential element in controlling latex production. The ethylene signalling pathway leads to the activation of Ethylene Response Factor (ERF) transcription factors. This family has been identified in Hevea brasiliensis. This study set out to understand the regulation of ERF genes during latex harvesting in relation to abiotic stress and hormonal treatments. Analyses of the relative transcript abundance were carried out for 35 HbERF genes in latex, in bark from mature trees and in leaves from juvenile plants under multiple abiotic stresses. Twenty-one HbERF genes were regulated by harvesting stress in laticifers, revealing an overrepresentation of genes in group IX. Transcripts of three HbERF-IX genes from HbERF-IXc4, HbERF-IXc5 and HbERF-IXc6 were dramatically accumulated by combining wounding, methyl jasmonate and ethylene treatments. When an ethylene inhibitor was used, the transcript accumulation for these three genes was halted, showing ethylene-dependent induction. Subcellular localization and transactivation experiments confirmed that several members of HbERF-IX are activator-type transcription factors. This study suggested that latex harvesting induces mechanisms developed for the response to abiotic stress. These mechanisms probably depend on various hormonal signalling pathways. Several members of HbERF-IX could be essential integrators of complex hormonal signalling pathways in Hevea.

  17. Homologous Hevea brasiliensis REF (Hevb1) and SRPP (Hevb3) present different auto-assembling.

    PubMed

    Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Peruch, Frédéric

    2014-02-01

    HbREF and HbSRPP are two Hevea brasiliensis proteins present on rubber particles, and probably involved in the coagulation of latex. Their function is unclear, but we previously discovered that REF had amyloid properties, which could be of particular interest during the coagulation process. First, we confirmed that REF and SRPP, homologous and principal proteins in hevea latex, are not glycoproteins. In this work, we investigated various aspects of protein interactions: aggregation, auto-assembling, yeast and erythrocyte agglutination, co-interactions by various biochemical (PAGE, spectroscopy, microscopy), biophysical (DLS, ellipsometry) and structural (TEM, ATR-FTIR, PM-IRRAS) approaches. We demonstrated that both proteins are auto-assembling into different aggregative states: REF polymerizes as an amyloid rich in β-sheets and forms quickly large aggregates (>μm), whereas SRPP auto-assembles in solution into stable nanomultimers of a more globular nature. Both proteins are however able to interact together, and SRPP may inhibit the amyloidogenesis of REF. REF is also able to interact with the membranes of yeasts and erythrocytes, leading to their agglutination. In addition, we also showed that both REF and SRPP did not have antimicrobial activity, whereas their activity on membranes has been clearly evidenced. We may suspect that these aggregative properties, even though they are clearly different, may occur during coagulation, when the membrane is destabilized. The interaction of proteins with membranes could help in the colloidal stability of latex, whereas the protein-protein interactions would contribute to the coagulation process, by bringing rubber particles together or eventually disrupting the particle monomembranes. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. De novo Transcriptome Analysis Reveals Distinct Defense Mechanisms by Young and Mature Leaves of Hevea brasiliensis (Para Rubber Tree)

    PubMed Central

    Fang, Yongjun; Mei, Hailiang; Zhou, Binhui; Xiao, Xiaohu; Yang, Meng; Huang, Yacheng; Long, Xiangyu; Hu, Songnian; Tang, Chaorong

    2016-01-01

    Along with changes in morphology in the course of maturation, leaves of Hevea brasiliensis become more resistant to leaf diseases, including the South American Leaf Blight (SALB), a devastating fungal disease of this economically important tree species. To understand the underlying mechanisms of this defense, and to identify the candidate genes involved, we sequenced the Hevea leaf transcriptome at four developmental stages (I to IV) by Illumina sequencing. A total of 62.6 million high-quality reads were generated, and assembled into 98,796 unique transcripts. We identified 3,905 differentially expressed genes implicated in leaf development, 67.8% (2,651) of which were during the transition to leaf maturation. The genes involved in cyanogenic metabolism, lignin and anthocyanin biosynthesis were noteworthy for their distinct patterns of expression between developing leaves (stages I to III) and mature leaves (stage IV), and the correlation with the change in resistance to SALB and the Oidium/Colletotrichum leaf fall. The results provide a first profile of the molecular events that relate to the dynamics of leaf morphology and defense strategies during Hevea leaf development. This dataset is beneficial to devising strategies to engineer resistance to leaf diseases as well as other in-depth studies in Hevea tree. PMID:27619402

  19. Changes in the Chemical Composition and Decay Resistance of Thermally-Modified Hevea brasiliensis Wood

    PubMed Central

    2016-01-01

    In this study the effect of thermal treatment on the equilibrium moisture content, chemical composition and biological resistance to decay fungi of juvenile and mature Hevea brasiliensis wood (rubber wood) was evaluated. Samples were taken from a 53-year-old rubber wood plantation located in Tabapuã, Sao Paulo, Brazil. The samples were thermally-modified at 180°C, 200°C and 220°C. Results indicate that the thermal modification caused: (1) a significant increase in the extractive content and proportional increase in the lignin content at 220°C; (2) a significant decrease in the equilibrium moisture content, holocelluloses, arabinose, galactose and xylose content, but no change in glucose content; and (3) a significant increase in wood decay resistance against both Pycnoporus sanguineus (L.) Murrill and Gloeophyllum trabeum (Pers.) Murrill decay fungi. The greatest decay resistance was achieved from treatment at 220°C which resulted in a change in wood decay resistance class from moderately resistant to resistant. Finally, this study also demonstrated that the influence of thermal treatment in mature wood was lower than in juvenile wood. PMID:26986200

  20. Rubber elongation factor (REF), a major allergen component in Hevea brasiliensis latex has amyloid properties.

    PubMed

    Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Bentaleb, Ahmed; Cullin, Christophe; Deffieux, Alain; Peruch, Frédéric

    2012-01-01

    REF (Hevb1) and SRPP (Hevb3) are two major components of Hevea brasiliensis latex, well known for their allergenic properties. They are obviously taking part in the biosynthesis of natural rubber, but their exact function is still unclear. They could be involved in defense/stress mechanisms after tapping or directly acting on the isoprenoid biosynthetic pathway. The structure of these two proteins is still not described. In this work, it was discovered that REF has amyloid properties, contrary to SRPP. We investigated their structure by CD, TEM, ATR-FTIR and WAXS and neatly showed the presence of β-sheet organized aggregates for REF, whereas SRPP mainly fold as a helical protein. Both proteins are highly hydrophobic but differ in their interaction with lipid monolayers used to mimic the monomembrane surrounding the rubber particles. Ellipsometry experiments showed that REF seems to penetrate deeply into the monolayer and SRPP only binds to the lipid surface. These results could therefore clarify the role of these two paralogous proteins in latex production, either in the coagulation of natural rubber or in stress-related responses. To our knowledge, this is the first report of an amyloid formed from a plant protein. This suggests also the presence of functional amyloid in the plant kingdom.

  1. Function of Hevea brasiliensis NAC1 in dehydration-induced laticifer differentiation and latex biosynthesis.

    PubMed

    Cao, Yuxin; Zhai, Jinling; Wang, Qichao; Yuan, Hongmei; Huang, Xi

    2017-01-01

    HbNAC1 is a transcription factor in rubber plants whose expression is induced by dehydration, leading to latex biosynthesis. Laticifer is a special tissue in Hevea brasiliensis where natural rubber is biosynthesized and accumulated. In young stems of epicormic shoots, the differentiation of secondary laticifers can be induced by wounding, which can be prevented when the wounding site is wrapped. Using this system, differentially expressed genes were screened by suppression subtractive hybridization (SSH) and macroarray analyses. This led to the identification of several dehydration-related genes that could be involved in laticifer differentiation and/or latex biosynthesis, including a NAC transcription factor (termed as HbNAC1). Tissue sections confirmed that local tissue dehydration was a key signal for laticifer differentiation. HbNAC1 was localized at the nucleus and showed strong transcriptional activity in yeast, suggesting that HbNAC1 is a transcription factor. Furthermore, HbNAC1 was found to bind to the cis-element CACG in the promoter region of the gene encoding the small rubber particle protein (SRPP). Transgenic experiments also confirmed that HbNAC1 interacted with the SRPP promoter when co-expressed, and enhanced expression of the reporter gene β-glucuronidase occurred in planta. In addition, overexpression of HbNAC1 in tobacco plants conferred drought tolerance. Together, the data suggest that HbNAC1 might be involved in dehydration-induced laticifer differentiation and latex biosynthesis.

  2. Identification and subcellular localization analysis of two rubber elongation factor isoforms on Hevea brasiliensis rubber particles.

    PubMed

    Dai, Longjun; Nie, Zhiyi; Kang, Guijuan; Li, Yu; Zeng, Rizhong

    2017-02-01

    Rubber elongation factor (REF) is the most abundant protein found on the rubber particles or latex from Hevea brasiliensis (the Para rubber tree) and is considered to play important roles in natural rubber (cis-polyisoprene) biosynthesis. 16 BAC (benzyldimethyl-n-hexadecylammonium chloride)/SDS-PAGE separations and mass spectrometric identification had revealed that two REF isoforms shared similar amino acid sequences and common C-terminal sequences. In this study, the gene sequences encoding these two REF isoforms (one is 23.6 kDa in size with 222 amino acid residues and the other is 27.3 kDa in size with 258 amino acid residues) were obtained. Their proteins were relatively enriched by sequential extraction of the rubber particle proteins and separated by 16 BAC/SDS-PAGE. The localization of these isoforms on the surfaces of rubber particles was further verified by western blotting and immunogold electron microscopy, which demonstrated that these two REF isoforms are mainly located on the surfaces of larger rubber particles and that they bind more tightly to rubber particles than the most abundant REF and SRPP (small rubber particle protein).

  3. Rubber Elongation Factor (REF), a Major Allergen Component in Hevea brasiliensis Latex Has Amyloid Properties

    PubMed Central

    Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Bentaleb, Ahmed; Cullin, Christophe; Deffieux, Alain; Peruch, Frédéric

    2012-01-01

    REF (Hevb1) and SRPP (Hevb3) are two major components of Hevea brasiliensis latex, well known for their allergenic properties. They are obviously taking part in the biosynthesis of natural rubber, but their exact function is still unclear. They could be involved in defense/stress mechanisms after tapping or directly acting on the isoprenoid biosynthetic pathway. The structure of these two proteins is still not described. In this work, it was discovered that REF has amyloid properties, contrary to SRPP. We investigated their structure by CD, TEM, ATR-FTIR and WAXS and neatly showed the presence of β-sheet organized aggregates for REF, whereas SRPP mainly fold as a helical protein. Both proteins are highly hydrophobic but differ in their interaction with lipid monolayers used to mimic the monomembrane surrounding the rubber particles. Ellipsometry experiments showed that REF seems to penetrate deeply into the monolayer and SRPP only binds to the lipid surface. These results could therefore clarify the role of these two paralogous proteins in latex production, either in the coagulation of natural rubber or in stress-related responses. To our knowledge, this is the first report of an amyloid formed from a plant protein. This suggests also the presence of functional amyloid in the plant kingdom. PMID:23133547

  4. Changes in the Chemical Composition and Decay Resistance of Thermally-Modified Hevea brasiliensis Wood.

    PubMed

    Severo, Elias Taylor Durgante; Calonego, Fred Willians; Sansígolo, Cláudio Angeli; Bond, Brian

    2016-01-01

    In this study the effect of thermal treatment on the equilibrium moisture content, chemical composition and biological resistance to decay fungi of juvenile and mature Hevea brasiliensis wood (rubber wood) was evaluated. Samples were taken from a 53-year-old rubber wood plantation located in Tabapuã, Sao Paulo, Brazil. The samples were thermally-modified at 180°C, 200°C and 220°C. Results indicate that the thermal modification caused: (1) a significant increase in the extractive content and proportional increase in the lignin content at 220°C; (2) a significant decrease in the equilibrium moisture content, holocelluloses, arabinose, galactose and xylose content, but no change in glucose content; and (3) a significant increase in wood decay resistance against both Pycnoporus sanguineus (L.) Murrill and Gloeophyllum trabeum (Pers.) Murrill decay fungi. The greatest decay resistance was achieved from treatment at 220°C which resulted in a change in wood decay resistance class from moderately resistant to resistant. Finally, this study also demonstrated that the influence of thermal treatment in mature wood was lower than in juvenile wood.

  5. HbNIN2, a cytosolic alkaline/neutral-invertase, is responsible for sucrose catabolism in rubber-producing laticifers of Hevea brasiliensis (para rubber tree).

    PubMed

    Liu, Shujin; Lan, Jixian; Zhou, Binhui; Qin, Yunxia; Zhou, Yihua; Xiao, Xiaohu; Yang, Jianghua; Gou, Jiqing; Qi, Jiyan; Huang, Yacheng; Tang, Chaorong

    2015-04-01

    In Hevea brasiliensis, an alkaline/neutral invertase (A/N-Inv) is responsible for sucrose catabolism in latex (essentially the cytoplasm of rubber-producing laticifers, the source of natural rubber) and implicated in rubber yield. However, neither the gene encoding this enzyme nor its molecular and biochemical properties have been well documented. Three Hevea A/N-Inv genes, namely HbNIN1, 2 and 3, were first cloned and characterized in planta and in Escherichia coli. Cellular localizations of HbNIN2 mRNA and protein were probed. From latex, active A/N-Inv proteins were purified, identified, and explored for enzymatic properties. HbNIN2 was identified as the major A/N-Inv gene functioning in latex based on its functionality in E. coli, its latex-predominant expression, the conspicuous localization of its mRNA and protein in the laticifers, and its expressional correlation with rubber yield. An active A/N-Inv protein was partially purified from latex, and determined as HbNIN2. The enhancement of HbNIN2 enzymatic activity by pyridoxal is peculiar to A/N-Invs in other plants. We conclude that HbNIN2, a cytosolic A/N-Inv, is responsible for sucrose catabolism in rubber laticifers. The results contribute to the studies of sucrose catabolism in plants as a whole and natural rubber synthesis in particular.

  6. Transcriptome analysis reveals novel features of the molecular events occurring in the laticifers of Hevea brasiliensis (para rubber tree).

    PubMed

    Ko, Jae-Heung; Chow, Keng-See; Han, Kyung-Hwan

    2003-11-01

    Latex of Hevea brasiliensis (Willd. ex A, Juss.) Mull. Arg. (Brazilian rubber tree) contains 30-50% (w/w) of natural rubber (cis-1,4-polyisoprene), which is an important raw material for many industrial uses. In order to gain insights into the molecular events occurring in latex, we analyzed more than 20,000 cDNA-AFLP-based TDFs (transcription-derived fragments) and 1176 ESTs. The results revealed several novel features of the latex transcriptome. First, the repertoire of the genes expressed in latex is unique. Only seven gene families accounted for more than 51% of the latex transcriptome. Among them, two of the most abundant ESTs were the genes encoding rubber particle proteins REF (rubber elongation factor) and SRPP (small rubber particle protein), comprising 29% of the total ESTs. Unexpectedly, several genes involved in the rubber biosynthesis were expressed at low levels in the latex. In fact, genes encoding cis -prenyltransferase (CPT), a potential candidate for rubber polymerase, were not present in the EST pool because of their low expression level. However, we were able to clone four full-length cDNAs by screening the same latex cDNA library used in the EST analysis and confirmed their enzyme activity in vitro. The second most abundant transcripts were defense- or stress-related genes, suggesting that defense is one of the functions of laticifers. Finally, the presence of the non-mevalonate DXP/MEP pathway for IPP synthesis in latex was noted by up-regulation of the 1-deoxy-D-xylulose 5-phosphate synthase gene.

  7. Water loss regulation in mature Hevea brasiliensis: effects of intermittent drought in the rainy season and hydraulic regulation.

    PubMed

    Isarangkool Na Ayutthaya, Supat; Do, Frederic C; Pannangpetch, Krirk; Junjittakarn, Junya; Maeght, Jean-Luc; Rocheteau, Alain; Cochard, Herve

    2011-07-01

    Effects of soil and atmospheric drought on whole-tree transpiration (E(T)), leaf water potential (Ψ(L)) and whole-tree hydraulic conductance (K(T)) were investigated in mature rubber trees (Hevea brasiliensis, clone RRIM 600) during the full canopy stage in the rainy season in a drought-prone area of northeast Thailand. Under well-watered soil conditions, transpiration was tightly regulated in response to high evaporative demand, i.e., above reference evapotranspiration (ET(0)) ~2.2 mm day(-1) or maximum vapor pressure deficit ~1.8 kPa. When the trees experienced intermittent soil drought E(T) decreased sharply when relative extractable water in the top soil was < 0.4. The midday leaf water potential (Ψ(md)) on sunny days did not change as a function of soil drought and remained stable at approximately - 1.95 MPa, i.e., displaying isohydric behavior. The decrease in E(T) was mainly due to the change in K(T). K(T) remained constant over a wide range of environmental conditions and decreased sharply at low soil water availability. A simple hydraulic model incorporating critical minimum water potential and the response of whole-tree hydraulic conductance to relative extractable water correctly simulated patterns of transpiration over 6 months. We conclude that an explicit and simplified framework of hydraulic limitation hypothesis was sufficient to describe water use regulation of a mature rubber tree stand in water-limited conditions. Given the complexity of constraints in the soil-plant-atmosphere pathway, our results confirm the relevance of this approach to synthesize the overall behavior of trees under drought.

  8. Isolation and structure elucidaton of polyphenols from Loranthus micranthus Linn. parasitic on Hevea brasiliensis with antiinflammatory property

    PubMed Central

    Agbo, Matthias Onyebuchi; Nworu, Chukwuemeka Sylvester; Okoye, Festus Basden Chied; Osadebe, Patience Ogoamaka

    2014-01-01

    The present study was carried out to evaluate the anti-inflammatory activities of polyphenols isolated from the leaves of mistletoe (Loranthus micranthus Linn.) parasitic on Hevea brasiliensis. The anti-inflammatory properties of the isolated compounds were evaluated on the basis of their ability to inhibit the production of nitric oxide (NO) and tumuor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS) activated RAW 264.7 mouse macrophages. Semi-preparative HPLC separation of the ethyl acetate (EtOAc) and butanol (n-BuOH) fractions of the leaves of mistletoe (Loranthus micranthus Linn) parasitic on Hevea brasiliensis led to the isolation of four polyphenols: 3-O-(3,4,5-trimethoxybenzoyl)-(-)-epicatechin (TMECG) (1); (-)-epicatechin-3-O-(3″-O-methyl)-gallate (ECG3″Me) (2); rutin (3) and peltatoside (4). Compounds 1-4 were isolated for the first time from this plant while 1 was isolated for the first time in nature. These compounds (1-4) were readily identified by comparison of their spectroscopic data with those reported in the literature. The polyphenols proved to have anti-inflammatory activity as evidenced by the suppression of inducible nitric oxide (iNO) and cytokine (TNF-α) levels in the culture supernatant of lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages. However, the study showed that the quercetin diglycosides showed stronger inhibition of proinflammatory mediators than the epicatechin derivates. These data provide evidence that polyphenolic compounds isolated from the mistletoe parasitic on Hevea brasiliensis may contribute to its anti-inflammatory properties by inhibiting the expression of inducible nitric oxide and proinflammatory cytokines such as tumour necrosis factor-α. PMID:26417309

  9. De novo transcriptome analysis of Hevea brasiliensis tissues by RNA-seq and screening for molecular markers

    PubMed Central

    2014-01-01

    Background The rubber tree, Hevea brasiliensis, is a species native to the Brazilian Amazon region and it supplies almost all the world’s natural rubber, a strategic raw material for a variety of products. One of the major challenges for developing rubber tree plantations is adapting the plant to biotic and abiotic stress. Transcriptome analysis is one of the main approaches for identifying the complete set of active genes in a cell or tissue for a specific developmental stage or physiological condition. Results Here, we report on the sequencing, assembling, annotation and screening for molecular markers from a pool of H. brasiliensis tissues. A total of 17,166 contigs were successfully annotated. Then, 2,191 Single Nucleotide Variation (SNV) and 1.397 Simple Sequence Repeat (SSR) loci were discriminated from the sequences. From 306 putative, mainly non-synonymous SNVs located in CDS sequences, 191 were checked for their ability to characterize 23 Hevea genotypes by an allele-specific amplification technology. For 172 (90%), the nucleotide variation at the predicted genomic location was confirmed, thus validating the different steps from sequencing to the in silico detection of the SNVs. Conclusions This is the first study of the H. brasiliensis transcriptome, covering a wide range of tissues and organs, leading to the production of the first developed SNP markers. This process could be amplified to a larger set of in silico detected SNVs in expressed genes in order to increase the marker density in available and future genetic maps. The results obtained in this study will contribute to the H. brasiliensis genetic breeding program focused on improving of disease resistance and latex yield. PMID:24670056

  10. Genome-wide identification and expression analysis of the metacaspase gene family in Hevea brasiliensis.

    PubMed

    Liu, Hui; Deng, Zhi; Chen, Jiangshu; Wang, Sen; Hao, Lili; Li, Dejun

    2016-08-01

    Metacaspases, a family of cysteine proteases, have been suggested to play important roles in programmed cell death (PCD) during plant development and stress responses. To date, no systematic characterization of this gene family has been reported in rubber tree (Hevea brasiliensis). In the present study, nine metacaspase genes, designated as HbMC1 to HbMC9, were identified from whole-genome sequence of rubber tree. Multiple sequence alignment and phylogenetic analyses suggested that these genes were divided into two types: type I (HbMC1-HBMC7) and type II (HbMC8 and HbMC9). Gene structure analysis demonstrated that type I and type II HbMCs separately contained four and two introns, indicating the conserved exon-intron organization of HbMCs. Quantitative real-time PCR analysis revealed that HbMCs showed distinct expression patterns in different tissues, suggesting the functional diversity of HbMCs in various tissues during development. Most of the HbMCs were regulated by drought, cold, and salt stress, implying their possible functions in regulating abiotic stress-induced cell death. Of the nine HbMCs, HbMC1, HbMC2, HbMC5, and HbMC8 displayed a significantly higher relative transcript accumulation in barks of tapping panel dryness (TPD) trees compared with healthy trees. In addition, the four genes were up-regulated by ethephon (ET) and methyl jasmonate (MeJA), indicating their potential involvement in TPD resulting from ET- or JA-induced PCD. In summary, this work provides valuable information for further functional characterization of HbMC genes in rubber tree.

  11. Variation of soil fertility and carbon sequestration by planting Hevea brasiliensis in Hainan Island, China.

    PubMed

    Cheng, Chun-Man; Wang, Ru-Song; Jiang, Ju-Sheng

    2007-01-01

    The development of rubber industry depends on the sustainable management of rubber plantation. To evaluate the environmental effects of planting Hevea brasiliensis on a subsystem of tropical forest ecosystem, the variation of soil fertility and carbon sequestration under rubber plantation within 30-year life period were investigated in Hainan Island. Results showed that (1) with the increase of stand age of rubber plantation, soil fertility decreased all along. From 1954 to 1995, soil organic matter, total N, available K and available P decreased by 48.2%, 54.1%, 56.7% and 64.1%, respectively. (2) If the complete return of litters was considered without additional fertilizer application to the soil of the rubber plantations, the consumption periods for P, N, K, Mg were only 825 years, 329 years, 94 years and 65 years, respectively. To improve soil fertility is essential for rubber plantation development. (3) The C sequestration of rubber trees per hectare accounts for 272.08 t within 30-year life period and 57.91% of them was fixed in litters. In comparison with C sequestration by rain forest (234.305 t/hm2) and by secondary rain forest (150.203 t/hm2), rubber forest has more potentials for C fixation. On the base of above results, the following measures would benefit the maintenance of soil fertility and the development of rubber industry, including applying fertilizer to maintain the balance of soil nutrients, intercropping leguminous plant to improve soil fertility, reducing the collection of litters, optimizing soil properties to improve element P availability such as applying CaCO3. The information gathered from the study can be used as baseline data for the sustainable management of rubber plantation elsewhere.

  12. Evapotranspiration of rubber (Hevea brasiliensis) cultivated at two plantation sites in Southeast Asia

    NASA Astrophysics Data System (ADS)

    Giambelluca, Thomas W.; Mudd, Ryan G.; Liu, Wen; Ziegler, Alan D.; Kobayashi, Nakako; Kumagai, Tomo'omi; Miyazawa, Yoshiyuki; Lim, Tiva Khan; Huang, Maoyi; Fox, Jefferson; Yin, Song; Mak, Sophea Veasna; Kasemsap, Poonpipope

    2016-02-01

    To investigate the effects of expanding rubber (Hevea brasiliensis) cultivation on water cycling in Mainland Southeast Asia (MSEA), evapotranspiration (ET) was measured within rubber plantations at Bueng Kan, Thailand, and Kampong Cham, Cambodia. After energy closure adjustment, mean annual rubber ET was 1211 and 1459 mm yr-1 at the Thailand and Cambodia sites, respectively, higher than that of other tree-dominated land covers in the region, including tropical seasonal forest (812-1140 mm yr-1), and savanna (538-1060 mm yr-1). The mean proportion of net radiation used for ET by rubber (0.725) is similar to that of tropical rainforest (0.729) and much higher than that of tropical seasonal forest (0.595) and savanna (0.548). Plant area index (varies with leaf area changes), explains 88.2% and 73.1% of the variance in the ratio of latent energy flux (energy equivalent of ET) to potential latent energy flux (LE/LEpot) for midday rain-free periods at the Thailand and Cambodia sites, respectively. High annual rubber ET results from high late dry season water use, associated with rapid refoliation by this brevideciduous species, facilitated by tapping of deep soil water, and by very high wet season ET, a characteristic of deciduous trees. Spatially, mean annual rubber ET increases strongly with increasing net radiation (Rn) across the three available rubber plantation observation sites, unlike nonrubber tropical ecosystems, which reduce canopy conductance at high Rn sites. High water use by rubber raises concerns about potential effects of continued expansion of tree plantations on water and food security in MSEA.

  13. Insights into rubber biosynthesis from transcriptome analysis of Hevea brasiliensis latex.

    PubMed

    Chow, Keng-See; Wan, Kiew-Lian; Isa, Mohd Noor Mat; Bahari, Azlina; Tan, Siang-Hee; Harikrishna, K; Yeang, Hoong-Yeet

    2007-01-01

    Hevea brasiliensis is the most widely cultivated species for commercial production of natural rubber (cis-polyisoprene). In this study, 10,040 expressed sequence tags (ESTs) were generated from the latex of the rubber tree, which represents the cytoplasmic content of a single cell type, in order to analyse the latex transcription profile with emphasis on rubber biosynthesis-related genes. A total of 3,441 unique transcripts (UTs) were obtained after quality editing and assembly of EST sequences. Functional classification of UTs according to the Gene Ontology convention showed that 73.8% were related to genes of unknown function. Among highly expressed ESTs, a significant proportion encoded proteins related to rubber biosynthesis and stress or defence responses. Sequences encoding rubber particle membrane proteins (RPMPs) belonging to three protein families accounted for 12% of the ESTs. Characterization of these ESTs revealed nine RPMP variants (7.9-27 kDa) including the 14 kDa REF (rubber elongation factor) and 22 kDa SRPP (small rubber particle protein). The expression of multiple RPMP isoforms in latex was shown using antibodies against REF and SRPP. Both EST and quantitative reverse transcription-PCR (QRT-PCR) analyses demonstrated REF and SRPP to be the most abundant transcripts in latex. Besides rubber biosynthesis, comparative sequence analysis showed that the RPMPs are highly similar to sequences in the plant kingdom having stress-related functions. Implications of the RPMP function in cis-polyisoprene biosynthesis in the context of transcript abundance and differential gene expression are discussed.

  14. Impact of age of rubber (Hevea brasiliensis) plantation on earthworm communities of West Tripura (India).

    PubMed

    Chaudhuri, P S; Bhattacharjee, Subhalaxmi; Dey, Animesh; Chattopadhyay, Sharmila; Bhattacharya, Dipto

    2013-01-01

    A comparative analysis of earthworm communities was carried out in the rubber plantations (Hevea brasiliensis) of different age groups in West Tripura to understand the impact of such exotic and monoculture plantation in biodiversity conservation. Earthworm communities were studied on monthly basis over a period of one year (2006-2007) in the 3, 10, 14, 20 and 25 year-old plantations. Among twelve earthworm species collected from the studied sites, six species belonged to Octochaetidae [Eutyphoeus assomensis Stephenson, Eutyphoeus comillahnus Michaelsen, Lennogaster chittagongensis (Stephensen), Octochaetona beatrix Gates, Dichogaster offinis Michaelsen, Lennogaster yeicus (Stephensen)], two species each to Megascolecidae [Metaphire houlleti (Perrier), Konchurio sp. 1] and Moniligastridae [Drowida nepalensis Michaelsen, Drawida papillifer papillifer Stephenson], one species each to Glossoscolecidae [Pontoscolex corethrurus (Muller)] and Ocnerodrilidae [Gordiodrilus elegans Beddard]. Exotic species P corethrurus, M. houlleti and native peregrine species like D. nepolensis and D. papillifer papillifer were distributed in all the age groups of plantation, while other species showed restricted distribution. P. corethrurus contributed more than 60% biomass and 70% density of earthworm communities in rubber plantation. With aging of rubber plantations both the densities and biomasses of earthworms increased. High contents of polyphenol, flavonoid and lignin in the litters of 3 and 10 year-old-rubber plantations through their effects on food intake, probably resulted to low biomass values of earthworms in those age groups of plantation. With further increase in the age of plantations beyond 10 years, polyphenol, flavonoid and lignin contents decreased. Accordingly the biomass of earthworms increased with increase in the age of plantation. Soil moisture increased with increase in the age of plantation and there was a good positive correlation between soil moisture and

  15. Characterization of HbWRKY1, a WRKY transcription factor from Hevea brasiliensis that negatively regulates HbSRPP.

    PubMed

    Wang, Ying; Guo, Dong; Li, Hui-Liang; Peng, Shi-Qing

    2013-10-01

    Small rubber particle protein (SRPP) is a major component of Hevea brasiliensis (H. brasiliensis) latex, which is involved in natural rubber (NR) biosynthesis. However, little information is available on the regulation of SRPP gene (HbSRPP) expression. To study the transcriptional regulation of HbSRPP, the yeast one-hybrid experiment was performed to screen the latex cDNA library using the HbSRPP promoter as bait. One cDNA that encodes the WRKY transcription factor, designated as HbWRKY1, was isolated from H. brasiliensis. HbWRKY1 contains a 1437 bp open reading frame that encodes 478 amino acids. The deduced HbWRKY1 protein was predicted to possess two conserved WRKY domains and a C2H2 zinc-finger motif. HbWRKY1 was expressed at different levels, with the highest transcription in the flower, followed by the bark, latex, and leaf. Furthermore, the co-expression of pHbSRP::GUS with CaMV35S::HbWRKY1 significantly decreased the GUS activity in transgenic tobacco, indicating that HbWRKY1 significantly suppressed the HbSRPP promoter. These results suggested that HbWRKY1 maybe a negative transcription regulator of HbSRPP involved in NR biosynthesis in H. brasiliensis. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  16. Breeding for disease resistance in Hevea spp. - status, potential threats, and possible strategies.

    Treesearch

    Chaendaekattu Narayanan; Kavitha K. Mydin

    2012-01-01

    Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg., a forest tree native to the tropical rain forests of Central and South America, has only been recently domesticated outside its natural range of distribution. Almost all of the commercially cultivated clones of H. brasiliensis represent a very narrow genetic base...

  17. Some ethylene biosynthesis and AP2/ERF genes reveal a specific pattern of expression during somatic embryogenesis in Hevea brasiliensis

    PubMed Central

    2012-01-01

    Background Ethylene production and signalling play an important role in somatic embryogenesis, especially for species that are recalcitrant in in vitro culture. The AP2/ERF superfamily has been identified and classified in Hevea brasiliensis. This superfamily includes the ERFs involved in response to ethylene. The relative transcript abundance of ethylene biosynthesis genes and of AP2/ERF genes was analysed during somatic embryogenesis for callus lines with different regeneration potential, in order to identify genes regulated during that process. Results The analysis of relative transcript abundance was carried out by real-time RT-PCR for 142 genes. The transcripts of ERFs from group I, VII and VIII were abundant at all stages of the somatic embryogenesis process. Forty genetic expression markers for callus regeneration capacity were identified. Fourteen markers were found for proliferating calli and 35 markers for calli at the end of the embryogenesis induction phase. Sixteen markers discriminated between normal and abnormal embryos and, lastly, there were 36 markers of conversion into plantlets. A phylogenetic analysis comparing the sequences of the AP2 domains of Hevea and Arabidopsis genes enabled us to predict the function of 13 expression marker genes. Conclusions This first characterization of the AP2/ERF superfamily in Hevea revealed dramatic regulation of the expression of AP2/ERF genes during the somatic embryogenesis process. The gene expression markers of proliferating callus capacity to regenerate plants by somatic embryogenesis should make it possible to predict callus lines suitable to be used for multiplication. Further functional characterization of these markers opens up prospects for discovering specific AP2/ERF functions in the Hevea species for which somatic embryogenesis is difficult. PMID:23268714

  18. Responses of seedlings of tropical woody plants to environmental stresses with emphasis on Theobroma cacao and Hevea brasiliensis

    SciTech Connect

    Sena Gomes, A.R.

    1987-01-01

    Relative humidity, flooding, temperature, wind, and SO/sub 2/ variously influenced physiological processes and growth of tropical woody plants, with emphasis on three Theobroma cacao varieties and three Hevea brasiliensis families. Stomata were smaller and more numerous in Theobroma than in Hevea. In Theobroma, but not Heavea, stomatal frequency decreased from the leaf base to the apex and from the midrib outward. Stomata of Theobroma cacao var. Catongo opened in high relative humidity (RH) and closed in low RH. The more open stomata in high RH were associated with high rates of photosynthesis, low leaf water potential, high water use efficiency (WUE), and low transpiration rate (TR). Variations in TR and WUE were correlated with changes in vapor pressure deficit. Other responses included stomatal closure, decreased chlorophyll content, leaf epinasty, production of hypertrophied lenticels and adventitious roots, and acceleration of ethylene production. Responses to flooding varied with species, Theobroma varieties and Hevea families. Effects of temperature regimes on growth varied with species, varieties and families, plant parts, growth parameters, and time of harvesting. Optimal temperatures for dry weight increase of stems or roots of Theobroma cacao var. Comum were 22.2 C; and 33.3 C for dry weight increase or relative growth rates of leaves or seedlings. Optimal temperatures for growth varied for Hevea families. Wind injured leaves of Theobroma cacao, with more injury by wind of 6.0 than 3.0 m s/sup -1/. Stomata were more open on windy than on calm days, but tended to close at high wind speeds. Wind lowered transpiration rate but the reduction was not correlated with leaf dehydration. SO/sub 2/ at 0.5, 1.0, or 1.5 ppm for 24 h did not injure Theobroma leaves but reduced dry weight increment of leaves of var. Catongo but not Catongo/Sial.

  19. How Do Rubber (Hevea brasiliensis) Plantations Cope with Seasonal Drought in Northern Thailand and Central Cambodia?

    NASA Astrophysics Data System (ADS)

    Kumagai, T.; Giambelluca, T. W.

    2014-12-01

    Rubber (Hevea brasiliensis Müll. Arg.) plantaitons are rapidly expanding throughout mainland Southeast Asia, potentially changing the partitioning of water, energy, and carbon at multiple scales, compared with the traditional land covers they are replacing. We have conducted eddy flux measurements in two rubber plantation sites: Som Sanuk (SS), located northern Thailand; and Cambodian Rubber Research Institute (CRRI), central Cambodia. We used combination of actual evapotranspiration (ET) flux measurements and an inversed version of a simple 2-layer ET model for estimating the mean canopy stomatal conductances (gs), which is among the most effective measures for describing the exchange characteristics. It is demonstrated how each studied rubber plantation copes with each strong seasonal drought via tree water use strategies. Potential tree water use deficit (precipitation (P) - potential evaporation (ET_POT)) for each season (i.e., December-February: DJF, March-May: MAM, June-August: JJA, and September-November: SON) revealed in which season and how the water use should be controlled. We found that in the season when actual tree water use deficit (P - ET) was negative (DJF and MAM), the deficit was compensated with soil water from the previous season at a depth of 0-2 m at the Thailand site, and from a depth of 0-3 m at CRRI. Two ecophysiological parameters, the reference value of gs (gsref) and the sensitivity of gs to atmospheric demand (m), as well as their proportionality (m/gsref), were derived from the logarithmic response curve of gs to vapor pressure deficit (D) for each season and each site. In both sites, gsref and m appeared to be less in DJF and MAM than each in the other three month periods (seasons). On average in a whole year, m/gsref was less than 0.6 at SS and almost 0.6 at the CRRI site, suggesting that there was less sufficient stomatal regulation at SS, where there might be little risk of water stress-induced hydraulic failure because of much

  20. Chloride-ion stimulation of the tonoplast H+-translocating ATPase from Hevea brasiliensis (rubber tree) latex. A dual mechanism.

    PubMed Central

    Marin, B P; Gidrol, X

    1985-01-01

    The effect of Cl- and other anions on the tonoplast H+-translocating ATPase (H+-ATPase) from Hevea brasiliensis (rubber tree) latex was investigated. Cl- and other anions stimulated the ATPase activity of tightly sealed vesicles prepared from Hevea tonoplast, with the following decreasing order of effectiveness: Cl- greater than Br- greater than SO4(2-) greater than NO3-. As indicated by the changes of the protonmotive potential difference, anion stimulation of tonoplast H+-ATPase was caused in part by the ability of these anions to dissipate the electrical potential. This interpretation assumes not a channelling of these anions against a membrane potential, negative-inside, but a modification of the permeability of these ions through the tonoplast membrane. In addition, Cl- and the other anions stimulated the ATPase activity solubilized from the tonoplast membrane. Consequently, the tonoplast H+-pumping ATPase can be considered as an anion-stimulated enzyme. These results are discussed in relation to various models described in the literature for the microsomal H+-ATPase systems claimed as tonoplast entities. PMID:2579642

  1. Rubber particle proteins REF1 and SRPP1 interact differently with native lipids extracted from Hevea brasiliensis latex.

    PubMed

    Wadeesirisak, Kanthida; Castano, Sabine; Berthelot, Karine; Vaysse, Laurent; Bonfils, Frédéric; Peruch, Frédéric; Rattanaporn, Kittipong; Liengprayoon, Siriluck; Lecomte, Sophie; Bottier, Céline

    2017-02-01

    Rubber particle membranes from the Hevea latex contain predominantly two proteins, REF1 and SRPP1 involved in poly(cis-1,4-isoprene) synthesis or rubber quality. The repartition of both proteins on the small or large rubber particles seems to differ, but their role in the irreversible coagulation of the rubber particle is still unknown. In this study we highlighted the different modes of interactions of both recombinant proteins with different classes of lipids extracted from Hevea brasiliensis latex, and defined as phospholipids (PL), glycolipids (GL) and neutral lipids (NL). We combined two biophysical methods, polarization modulated-infrared reflection adsorption spectroscopy (PM-IRRAS) and ellipsometry to elucidate their interactions with monolayers of each class of lipids. REF1 and SRPP1 interactions with native lipids are clearly different; SRPP1 interacts mostly in surface with PL, GL or NL, without modification of its structure. In contrast REF1 inserts deeply in the lipid monolayers with all lipid classes. With NL, REF1 is even able to switch from α-helice conformation to β-sheet structure, as in its aggregated form (amyloid form). Interaction between REF1 and NL may therefore have a specific role in the irreversible coagulation of rubber particles. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Identification of expression profiles of tapping panel dryness (TPD) associated genes from the latex of rubber tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Venkatachalam, Perumal; Thulaseedharan, Arjunan; Raghothama, Kashchandra

    2007-07-01

    Tapping panel dryness (TPD) occurrence in high latex yielding rubber tree (Hevea brasiliensis) is characterized by the partial or complete cessation of latex flow upon tapping leading to severe loss in natural rubber production around the world. The goal of this study was to identify genes whose mRNA transcript levels are differentially regulated in rubber tree during the onset of TPD. To isolate TPD responsive genes, two cDNA libraries (forward and reverse) from total RNA isolated from latex of healthy and TPD trees were constructed using suppression subtractive hybridization (SSH) method. In total, 1,079 EST clones were obtained from two cDNA libraries and screened by reverse Northern blot analysis. Screening results revealed that about 352 clones were differentially regulated and they were selected for sequencing. Based on the nucleotide sequence data, the putative functions of cDNA clones were predicted by BLASTX/BLASTN analysis. Among these, 64 were genes whose function had been previously identified while the remaining clones were genes with either unknown protein function or insignificant similarity to other protein/DNA/EST sequences in existing databases. RT-PCR analysis was carried out to validate the up-regulated genes from both the libraries. Among them, two genes were strongly down-regulated in TPD trees. The level of mRNA transcripts of these two genes was further examined by conventional Northern and RT-PCR analysis. Results indicated that the expression level of two genes was significantly lower in TPD trees compared to healthy trees. Many TPD associated genes were also up-regulated in TPD trees suggesting that they may be involved in triggering programmed cell death (PCD) during the onset of TPD syndrome. The results presented here demonstrate that SSH technique provides a powerful complementary approach for the identification of TPD related genes from rubber tree.

  3. Comparative proteomic analysis of latex from Hevea brasiliensis treated with Ethrel and methyl jasmonate using iTRAQ-coupled two-dimensional LC-MS/MS.

    PubMed

    Dai, Longjun; Kang, Guijuan; Nie, Zhiyi; Li, Yu; Zeng, Rizhong

    2016-01-30

    Ethrel (ET) is an effective and widely used latex yield stimulant of Hevea brasiliensis (Pará rubber tree), and jasmonate (JA) is a key inducer of laticifer differentiation in this plant. To examine variations in the latex proteome caused by these phytohormones, ET and methyl jasmonate (MeJA) were applied to Reyan 7-33-97 rubber tree clones, and comparative proteomic analyses were conducted. On the basis of a transcriptome shotgun assembly (TSA) sequence database and an iTRAQ-coupled two-dimensional LC-MS/MS approach, 1499 latex proteins belonging to 1078 clusters were identified. With a 1.5-fold cut-off value to determine up- and down-regulated proteins, a total of 101 latex proteins were determined to be regulated by ET and/or MeJA via pairwise comparisons among the three exposure durations (0 h, 6 h, and 48 h). Proteins associated with latex regeneration, including phosphoenolpyruvate carboxylase and acetyl-CoA C-acetyltransferase, and those associated with latex flow, such as chitinase and a sieve element occlusion protein, were affected by the application of ET. Chitinase and polyphenol oxidase were also found to be regulated by MeJA. The findings of this study may provide new insight into the roles of phytohormones in latex yield and the causative mechanisms of laticifer differentiation in rubber trees. On the basis of a transcriptome shotgun assembly (TSA) sequence database and an iTRAQ-coupled two-dimensional LC-MS/MS approach, the most comprehensive proteome of the latex was profiled, and the ethylene-/jasmonate-responsive proteins were identified in the latex of H. brasiliensis. The findings of this study may provide new insight into the role of phytohormones in latex yield and the causative mechanisms of laticifer differentiation in rubber trees. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Distribution of molar mass and branching index of natural rubber from Hevea brasiliensis trees of different age by size exclusion chromatography coupled with online viscometry.

    PubMed

    Phan, T N; Lan, N T; Nga, N T

    2004-05-01

    Natural rubber from hevea brasiliensis trees (Thailand, RRIM 600 clone) of different age (8, 20, and 35 years) were characterized by size exclusion chromatography coupled with online viscometry according to their distribution of molar mass and branching index at a temperature of 70 degrees C using cyclohexane as solvent. Washing with an aqueous solution of sodium dodecylsulfate and subsequent saponification purified the natural rubber samples. With this procedure physical branching points caused by phospholipids, proteins and hydrophobic terminal units, mainly fatty acids, of the natural rubber (cis-1,4-polyisoprene) molecule, could be removed leading to completely soluble polymer samples. All samples investigated possess a very broad (10 to 50,000 kg/mol) and distinct bimodal molar mass distribution. With increasing age the peak area in the low molar mass region decreases favoring the peak area in the high molar mass region. By plotting the branching index as a function of the both, the molar mass and the age of the trees.

  5. HbMADS4, a MADS-box Transcription Factor from Hevea brasiliensis, Negatively Regulates HbSRPP

    PubMed Central

    Li, Hui-Liang; Wei, Li-Ran; Guo, Dong; Wang, Ying; Zhu, Jia-Hong; Chen, Xiong-Ting; Peng, Shi-Qing

    2016-01-01

    In plants MADS-box transcription factors (TFs) play important roles in growth and development. However, no plant MADS-box gene has been identified to have a function related to secondary metabolites regulation. Here, a MADS-box TF gene, designated as HbMADS4, was isolated from Hevea brasiliensis by the yeast one-hybrid experiment to screen the latex cDNA library using the promoter of the gene encoding H. brasiliensis small rubber particle protein (HbSRPP) as bait. HbMADS4 was 984-bp containing 633-bp open reading frame encoding a deduced protein of 230 amino acid residues with a typical conserved MADS-box motif at the N terminus. HbMADS4 was preferentially expressed in the latex, but little expression was detected in the leaves, flowers, and roots. Its expression was inducible by methyl jasmonate and ethylene. Furthermore, transient over-expression and over-expression of HbMADS4 in transgenic tobacco plants significantly suppressed the activity of the HbSRP promoter. Altogether, it is proposed that HbMADS4 is a negative regulator of HbSRPP which participates in the biosynthesis of natural rubber. PMID:27895659

  6. De novo assembly and transcriptome analysis of the rubber tree (Hevea brasiliensis) and SNP markers development for rubber biosynthesis pathways.

    PubMed

    Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

    2014-01-01

    Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection.

  7. De Novo Assembly and Transcriptome Analysis of the Rubber Tree (Hevea brasiliensis) and SNP Markers Development for Rubber Biosynthesis Pathways

    PubMed Central

    Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

    2014-01-01

    Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection. PMID:25048025

  8. Trichoderma amazonicum, a new endophytic species on Hevea brasiliensis and H. guianensis from the Amazon basin

    USDA-ARS?s Scientific Manuscript database

    A new species of Trichoderma (teleomorph Hypocrea, Ascomycota, Sordariomycetes, Hypocreales, Hypocreaceae), T. amazonicum, endophytic on the living sapwood and leaves of Hevea spp. trees is described. Trichoderma amazonicum is distinguished from closely related species in the Harzianum clade (e.g. ...

  9. Proteome analysis of the large and the small rubber particles of Hevea brasiliensis using 2D-DIGE.

    PubMed

    Xiang, Qiulan; Xia, Kecan; Dai, Longjun; Kang, Guijuan; Li, Yu; Nie, Zhiyi; Duan, Cuifang; Zeng, Rizhong

    2012-11-01

    The rubber particle is a specialized organelle in which natural rubber is synthesised and stored in the laticifers of Hevea brasiliensis (para rubber tree). It has been demonstrated that the small rubber particles (SRPs) has higher rubber biosynthesis ratio than the large rubber particles (LRPs), but the underlying molecular mechanism still remains unknown. In this study, LRPs and SRPs were firstly separated from the fresh latex using differential centrifugation, and two-dimensional difference in-gel electrophoresis (2D-DIGE) combined with MALDI-TOF/TOF was then applied to investigate the proteomic alterations associated with the changed rubber biosynthesis capacity between LRPs and SRPs. A total of 53 spots corresponding to 22 gene products, were significantly altered with the |ratio|≥2.0 and T value ≤0.05, among which 15 proteins were up-regulated and 7 were down-regulated in the SRPs compared with the LRPs. The 15 up-regulated proteins in the SRPs included small rubber particle protein (SRPP), 3-hydroxy-3-methylglutaryl-CoA synthase (HMGCS), phospholipase D alpha (PLD α), ethylene response factor 2, eukaryotic translation initiation factor 5A isoform IV (eIF 5A-4), 70-kDa heat shock cognate protein (HSC 70), several unknown proteins, etc., whereas the 7 up-regulated proteins in the LRPs were rubber elongation factor (REF, 19.6kDa), ASR-like protein 1, REF-like stress-related protein 1, a putative phosphoglyceride transfer family protein, β-1,3-glucanase, a putative retroelement, and a hypothetical protein. Since several proteins related to rubber biosynthesis were differentially expressed between LRPs and SRPs, the comparative proteome data may provide useful insights into understanding the mechanism involved in rubber biosynthesis and latex coagulation in H. brasiliensis.

  10. Over-expression of a cytosolic isoform of the HbCuZnSOD gene in Hevea brasiliensis changes its response to a water deficit.

    PubMed

    Leclercq, J; Martin, F; Sanier, C; Clément-Vidal, A; Fabre, D; Oliver, G; Lardet, L; Ayar, A; Peyramard, M; Montoro, P

    2012-10-01

    Hevea brasiliensis is the main commercial source of natural rubber. Reactive oxygen species (ROS) scavenging systems are involved in various biotic and abiotic stresses. Genetic engineering was undertaken to study the strengthening of plant defences by antioxidants. To that end, Hevea transgenic plant lines over-expressing a Hevea brasiliensis cytosolic HbCuZnSOD gene were successfully established and regenerated. Over-expression of the HbCuZnSOD gene was not clearly related to an increase in SOD activity in plant leaves. The impact of HbCuZnSOD gene over-expression in somatic embryogenesis and in plant development are presented and discussed. The water deficit tolerance of two HbCuZnSOD over-expressing lines was evaluated. The physiological parameters of transgenic plantlets subjected to a water deficit suggested that plants from line TS4T8An displayed lower stomatal conductance and a higher proline content. Over-expression of the HbCuZnSOD gene and activation of all ROS-scavenging enzymes also suggested that protection against ROS was more efficient in the TS4T8An transgenic line.

  11. Increased vascular permeability, angiogenesis and wound healing induced by the serum of natural latex of the rubber tree Hevea brasiliensis.

    PubMed

    Mendonça, Ricardo José; Maurício, Vanessa Beatriz; Teixeira, Larissa de Bortolli; Lachat, João José; Coutinho-Netto, Joaquim

    2010-05-01

    Increases in vascular permeability and angiogenesis are crucial events to wound repair, tumoral growth and revascularization of tissues submitted to ischemia. An increased vascular permeability allows a variety of cytokines and growth factors to reach the damaged tissue. Nevertheless, the angiogenesis supply tissues with a wide variety of nutrients and is also important to metabolites clearance. It has been suggested that the natural latex from Hevea brasiliensis showed wound healing properties and angiogenic activity. Thus, the purpose of this work was to characterize its angiogenic activity and its effects on vascular permeability and wound healing. The serum fraction of the latex was separated from the rubber with reduction of the pH. The activity of the dialyzed serum fraction on the vascular permeability injected in subcutaneous tissue was assayed according Mile's method. The angiogenic activity was determined using a chick embryo chorioallantoic membrane assay and its effects on the wound-healing process was determined by the rabbit ear dermal ulcer model. The serum fraction showed evident angiogenic effect and it was effective in enhancing vascular permeability. In dermal ulcers, this material significantly accelerated wound healing. Moreover, the serum fraction boiled and treated with proteases lost these activities. These results are in accordance with the enhancement of wound healing observed in clinical trials carried out with a biomembrane prepared with the same natural latex.

  12. HbMyb1, a Myb transcription factor from Hevea brasiliensis, suppresses stress induced cell death in transgenic tobacco.

    PubMed

    Peng, Shi-Qing; Wu, Kun-Xin; Huang, Gui-Xiu; Chen, Shou-Cai

    2011-12-01

    Tapping panel dryness (TPD) is a complex physiological syndrome found widely in rubber tree (Hevea brasiliensis) plantations that causes severe yield loss in natural rubber-producing countries. In an earlier study, we confirmed that there is a negative correlation between HbMyb1 expression and TPD severity. To further investigate the function of HbMyb1 in TPD, HbMyb1 was over-expressed in tobacco controlled by a CaMV 35S promoter. In transgenic plants expressing HbMyb1, cell death induced by UV-B irradiation, paraquat and the hypersensitive reaction to necrotrophic fungal infection (Botrytis cinerea) was suppressed with a close correlation between HbMyb1 protein levels and the extent of suppression. In addition the nuclear condensation and degradation were observed in laticifer cells of TPD trees, while the nucleus of laticifer cells of healthy trees was morphologically normal. On the basis of the results described above, we propose that HbMyb1 maybe suppress stress induced cell death in rubber trees.

  13. Transcriptome sequencing and analysis of rubber tree (Hevea brasiliensis Muell.) to discover putative genes associated with tapping panel dryness (TPD).

    PubMed

    Liu, Jin-Ping; Xia, Zhi-Qiang; Tian, Xiao-Yan; Li, Yi-Jian

    2015-05-21

    Tapping panel dryness (TPD) involves in the partial or complete cessation of latex flow thus seriously affect latex production in rubber tree (Hevea brasiliensis). Numerous studies have been conducted to define its origin and nature, but the molecular nature and mechanism of TPD occurrence remains unknown. This study is committed to de novo sequencing and comparative analysis of the transcriptomes of healthy (H) and TPD-affected (T) rubber trees to identify the genes and pathways related to the TPD. Total raw reads of 34,632,012 and 35,913,020 bp were obtained from H and T library, respectively using Illumina Hiseq 2000 sequencing technology. De novo assemblies yielded 141,456 and 169,285 contigs, and 96,070 and 112,243 unigenes from H and T library, respectively. Among 73597 genes, 22577 genes were identified as differential expressed genes between H and T library via comparative transcript profiling. A majority of genes involved in natural rubber biosynthesis and jasmonate synthesis with most potential relevance in TPD occurrence were found to be differentially expressed. In TPD-affected trees, the expression of most genes related to the latex biosynthesis and jasmonate synthesis was severely inhibited and is probably the direct cause of the TPD. These new de novo transcriptome data sets provide a significant resource for the discovery of genes related to TPD and improve our understanding of the occurrence and maintainace of TPD.

  14. Depolymerization of beta-chitin to mono- and disaccharides by the serum fraction from the para rubber tree, Hevea brasiliensis.

    PubMed

    Klaikherd, Akamol; Siripastr Jayanta, M L; Boonjawat, Jariya; Aiba, Sei-ichi; Sukwattanasinitt, Mongkol

    2004-12-06

    The serum fraction of latex from Hevea brasiliensis, the para rubber tree, is known to contain an endo-chitinolytic enzyme, hevamine. Herein the activity of the rubber serum towards beta-chitin is investigated. The serum contained 6 mg/mL of protein and a chitinolytic activity of 18 mU permg of protein. The optimum ratio of enzyme to chitin was 0.22 mU/mg, and the optimum substrate concentration was 60 mg/mL. The optimum pH range was pH2-4, and the optimum temperature was 45 degrees C. At these conditions both (GlcNAc)2 and GlcNAc were produced in a molar ratio of approximately 2:1. The hydrolysis of 300 mg of chitin with 64 mU of the rubber serum for 8 days under the optimum conditions gave 39 mg of GlcNAc and 108 mg of (GlcNAc)2 as determined by HPLC. Mixing the rubber serum preparation with an Aspergillus niger pectinase preparation containing beta-N-acetylhexosaminidase can be used to produce almost exclusively the GlcNAc monomer in about 50% yield.

  15. Identification of Powdery Mildew Responsive Genes in Hevea brasiliensis through mRNA Differential Display.

    PubMed

    Li, Xiang; Bi, Zhenghong; Di, Rong; Liang, Peng; He, Qiguang; Liu, Wenbo; Miao, Weiguo; Zheng, Fucong

    2016-01-29

    Powdery mildew is an important disease of rubber trees caused by Oidium heveae B. A. Steinmann. As far as we know, none of the resistance genes related to powdery mildew have been isolated from the rubber tree. There is little information available at the molecular level regarding how a rubber tree develops defense mechanisms against this pathogen. We have studied rubber tree mRNA transcripts from the resistant RRIC52 cultivar by differential display analysis. Leaves inoculated with the spores of O. heveae were collected from 0 to 120 hpi in order to identify pathogen-regulated genes at different infection stages. We identified 78 rubber tree genes that were differentially expressed during the plant-pathogen interaction. BLAST analysis for these 78 ESTs classified them into seven functional groups: cell wall and membrane pathways, transcription factor and regulatory proteins, transporters, signal transduction, phytoalexin biosynthesis, other metabolism functions, and unknown functions. The gene expression for eight of these genes was validated by qRT-PCR in both RRIC52 and the partially susceptible Reyan 7-33-97 cultivars, revealing the similar or differential changes of gene expressions between these two cultivars. This study has improved our overall understanding of the molecular mechanisms of rubber tree resistance to powdery mildew.

  16. Identification of Powdery Mildew Responsive Genes in Hevea brasiliensis through mRNA Differential Display

    PubMed Central

    Li, Xiang; Bi, Zhenghong; Di, Rong; Liang, Peng; He, Qiguang; Liu, Wenbo; Miao, Weiguo; Zheng, Fucong

    2016-01-01

    Powdery mildew is an important disease of rubber trees caused by Oidium heveae B. A. Steinmann. As far as we know, none of the resistance genes related to powdery mildew have been isolated from the rubber tree. There is little information available at the molecular level regarding how a rubber tree develops defense mechanisms against this pathogen. We have studied rubber tree mRNA transcripts from the resistant RRIC52 cultivar by differential display analysis. Leaves inoculated with the spores of O. heveae were collected from 0 to 120 hpi in order to identify pathogen-regulated genes at different infection stages. We identified 78 rubber tree genes that were differentially expressed during the plant–pathogen interaction. BLAST analysis for these 78 ESTs classified them into seven functional groups: cell wall and membrane pathways, transcription factor and regulatory proteins, transporters, signal transduction, phytoalexin biosynthesis, other metabolism functions, and unknown functions. The gene expression for eight of these genes was validated by qRT-PCR in both RRIC52 and the partially susceptible Reyan 7-33-97 cultivars, revealing the similar or differential changes of gene expressions between these two cultivars. This study has improved our overall understanding of the molecular mechanisms of rubber tree resistance to powdery mildew. PMID:26840302

  17. Recent advances in anther culture of Hevea brasiliensis (Muell.-Arg.).

    PubMed

    Chen, Z; Qian, C; Qin, M; Xu, X; Xiao, Y

    1982-06-01

    The yield of pollen embryoids from cultured Hevea anthers was increased 4 fold by optimizing the proportion of ammonium nitrate to potassium nitrate in the dedifferentiation medium. For optimal differentiation of pollen embryoids, kinetin, 2,4-D and α-naphtalene acetic acid are required. Anther culture for 50 days on the dedifferentiation medium is a prerequisite for the selective development of calli and embryoids from microspores.The determination of chromosome numbers in embryoids, plantlets and regenerated trees reveals that they originate from (poly)haploid pollen grains (n=2x=18). Aneuploid, triploid (3x=27) and tetraploid (4x=36) cells were encountered in increasing frequencies as the embryoids and plants developed. A few haploid cells with 9 chromosomes were consistently observed. Buds from shoots with mixoploid chromosome numbers can be grafted and the change in the chromosome constitution of the developing new shoots followed.

  18. Regulation of MIR Genes in Response to Abiotic Stress in Hevea brasiliensis

    PubMed Central

    Gébelin, Virginie; Leclercq, Julie; Hu, Songnian; Tang, Chaorong; Montoro, Pascal

    2013-01-01

    Increasing demand for natural rubber (NR) calls for an increase in latex yield and also an extension of rubber plantations in marginal zones. Both harvesting and abiotic stresses lead to tapping panel dryness through the production of reactive oxygen species. Many microRNAs regulated during abiotic stress modulate growth and development. The objective of this paper was to study the regulation of microRNAs in response to different types of abiotic stress and hormone treatments in Hevea. Regulation of MIR genes differs depending on the tissue and abiotic stress applied. A negative co-regulation between HbMIR398b with its chloroplastic HbCuZnSOD target messenger is observed in response to salinity. The involvement of MIR gene regulation during latex harvesting and tapping panel dryness (TPD) occurrence is further discussed. PMID:24084713

  19. Regulation of MIR genes in response to abiotic stress in Hevea brasiliensis.

    PubMed

    Gébelin, Virginie; Leclercq, Julie; Hu, Songnian; Tang, Chaorong; Montoro, Pascal

    2013-09-27

    Increasing demand for natural rubber (NR) calls for an increase in latex yield and also an extension of rubber plantations in marginal zones. Both harvesting and abiotic stresses lead to tapping panel dryness through the production of reactive oxygen species. Many microRNAs regulated during abiotic stress modulate growth and development. The objective of this paper was to study the regulation of microRNAs in response to different types of abiotic stress and hormone treatments in Hevea. Regulation of MIR genes differs depending on the tissue and abiotic stress applied. A negative co-regulation between HbMIR398b with its chloroplastic HbCuZnSOD target messenger is observed in response to salinity. The involvement of MIR gene regulation during latex harvesting and tapping panel dryness (TPD) occurrence is further discussed.

  20. Quantitative expression analysis of drought responsive genes in clones of Hevea with varying levels of drought tolerance.

    PubMed

    Luke, Lisha P; Mohamed Sathik, M B; Thomas, Molly; Kuruvilla, Linu; Sumesh, K V; Annamalainathan, K

    2015-04-01

    In order to meet the ever rising global demand for natural rubber, cultivation of Hevea is being extended to non-traditional regions of India where extreme climatic conditions like drought and low temperature negatively influence the crop performance. In order to ensure maximum productivity, identification of drought tolerant clones of Hevea which can cope up with stress and give better crop yield is essential. Several attempts have been made previously to identify genes that are associated with drought tolerance in Hevea. In the present study, quantitative expression analysis was made using quantitative PCR for seven drought associated transcripts in four clones of Hevea with varying levels of drought tolerance. Among the seven genes studied, Mitogen Activated Protein (MAP) kinase, Myeloblastosis (Myb) transcription factor, C-repeat responsive element/Dehydration Responsive Element (CRT/DRE) binding factor and Nuclear Factor Y subunit A (NFYA) showed a positive association with drought tolerance. Transcripts of ascorbate peroxidase and heat shock protein 70 (HSP 70) did not show any correlation with drought tolerance. Interestingly, catalase gene was found down regulated in all the clones under drought condition. The possible role of these genes based on their level of gene expression in four different clones of Hevea with varying levels of drought tolerance is discussed.

  1. Micro-organisms in latex and natural rubber coagula of Hevea brasiliensis and their impact on rubber composition, structure and properties.

    PubMed

    Salomez, M; Subileau, M; Intapun, J; Bonfils, F; Sainte-Beuve, J; Vaysse, L; Dubreucq, E

    2014-10-01

    Natural rubber, produced by coagulation of the latex from the tree Hevea brasiliensis, is an important biopolymer used in many applications for its outstanding properties. Besides polyisoprene, latex is rich in many nonisoprene components such as carbohydrates, proteins and lipids and thereby constitutes a favourable medium for the development of micro-organisms. The fresh rubber coagula obtained by latex coagulation are not immediately processed, allowing the development of various microbial communities. The time period between tree tapping and coagula processing is called maturation, during which an evolution of the properties of the corresponding dry natural rubber occurs. This evolution is partly related to the activity of micro-organisms and to the modification of the biochemical composition. This review synthesizes the current knowledge on microbial populations in latex and natural rubber coagula of H. brasiliensis and the changes they induce on the biochemistry and technical properties of natural rubber during maturation.

  2. The Hevea brasiliensis XIP aquaporin subfamily: genomic, structural and functional characterizations with relevance to intensive latex harvesting.

    PubMed

    Lopez, David; Amira, Maroua Ben; Brown, Daniel; Muries, Beatriz; Brunel-Michac, Nicole; Bourgerie, Sylvain; Porcheron, Benoit; Lemoine, Remi; Chrestin, Hervé; Mollison, Ewan; Di Cola, Alessandra; Frigerio, Lorenzo; Julien, Jean-Louis; Gousset-Dupont, Aurélie; Fumanal, Boris; Label, Philippe; Pujade-Renaud, Valérie; Auguin, Daniel; Venisse, Jean-Stéphane

    2016-07-01

    X-Intrinsic Proteins (XIP) were recently identified in a narrow range of plants as a full clade within the aquaporins. These channels reportedly facilitate the transport of a wide range of hydrophobic solutes. The functional roles of XIP in planta remain poorly identified. In this study, we found three XIP genes (HbXIP1;1, HbXIP2;1 and HbXIP3;1) in the Hevea brasiliensis genome. Comprehensive bioinformatics, biochemical and structural analyses were used to acquire a better understanding of this AQP subfamily. Phylogenetic analysis revealed that HbXIPs clustered into two major groups, each distributed in a specific lineage of the order Malpighiales. Tissue-specific expression profiles showed that only HbXIP2;1 was expressed in all the vegetative tissues tested (leaves, stem, bark, xylem and latex), suggesting that HbXIP2;1 could take part in a wide range of cellular processes. This is particularly relevant to the rubber-producing laticiferous system, where this isoform was found to be up-regulated during tapping and ethylene treatments. Furthermore, the XIP transcriptional pattern is significantly correlated to latex production level. Structural comparison with SoPIP2;1 from Spinacia oleracea species provides new insights into the possible role of structural checkpoints by which HbXIP2;1 ensures glycerol transfer across the membrane. From these results, we discuss the physiological involvement of glycerol and HbXIP2;1 in water homeostasis and carbon stream of challenged laticifers. The characterization of HbXIP2;1 during rubber tree tapping lends new insights into molecular and physiological response processes of laticifer metabolism in the context of latex exploitation.

  3. Microarrays of recombinant Hevea brasiliensis proteins: a novel tool for the component-resolved diagnosis of natural rubber latex allergy.

    PubMed

    Ott, H; Schröder, C; Raulf-Heimsoth, M; Mahler, V; Ocklenburg, C; Merk, H F; Baron, J M

    2010-01-01

    Component-resolved diagnosis using microarray technology has recently been introduced in clinical allergology, but its applicability in patients with natural rubber latex (NRL) allergy has not been investigated. To evaluate the utility of microarray-based immunoglobulin (Ig) E detection in the diagnostic workup of NRL allergy and to compare this new diagnostic tool with established methods of NRL-specific IgE detection. We investigated 52 adults with immediate-type NRL allergy and 50 control patients. Determination of specific serum IgE against 8 recombinant Hevea brasiliensis allergen components was performed using a customized allergen microarray and a conventional fluorescence enzyme immunoassay (FEIA). The panel of microarrayed allergen components was shown to represent a comprehensive repertoire of clinically relevant NRL proteins. NRL-specific IgE recognition patterns and sensitization rates determined by microarray analysis were similar to those obtained by conventional FEIA. The diagnostic sensitivity rates of combined single-component data were not significantly different for the respective recombinant test system, whereas the sensitivity level of extract-based FEIA analysis was markedly higher. The current study provides evidence that microarrays of recombinant NRL allergen components are a suitable new tool for the diagnosis of NRL-specific sensitization.They show performance characteristics comparable to those of current diagnostic tests and could be indicated in small children in whom only limited blood volumes are obtainable. Further large-scale studies in unselected patient populations and in high-risk groups are warranted before the microarray can be introduced into routine management of patients with NRL allergy.

  4. Identification, Functional Study, and Promoter Analysis of HbMFT1, a Homolog of MFT from Rubber Tree (Hevea brasiliensis)

    PubMed Central

    Bi, Zhenghong; Li, Xiang; Huang, Huasun; Hua, Yuwei

    2016-01-01

    A homolog of MOTHER OF FT AND TFL1 (MFT) was isolated from Hevea brasiliensis and its biological function was investigated. Protein multiple sequence alignment and phylogenetic analysis revealed that HbMFT1 conserved critical amino acid residues to distinguish MFT, FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1)-like proteins and showed a closer genetic relationship to the MFT-like group. The accumulation of HbMFT1 was generally detected in various tissues except pericarps, with the highest expression in embryos and relatively higher expression in roots and stems of seedlings, flowering inflorescences, and male and female flowers. HbMFT1 putative promoter analysis showed that tissue-specific, environmental change responsive and hormone-signaling responsive elements were generally present. HbMFT1 was strongly induced under a short-day condition at 28 °C, with the highest expression after the onset of a day. Overexpression of HbMFT1 inhibited seed germination, seedling growth, and flowering in transgenic Arabidopsis. The qRT-PCR further confirmed that APETALA1 (AP1) and FRUITFULL (FUL) were drastically down-regulated in 35S::HbMFT1 plants. A histochemical β-glucuronidase (GUS) assay showed that HbMFT1::GUS activity was mainly detected in stamens and mature seeds coinciding with its original expression and notably induced in rosette leaves and seedlings of transgenic Arabidopsis by exogenous abscisic acid (ABA) due to the presence of ABA cis-elements in HbMFT1 promoter. These results suggested that HbMFT1 was mainly involved in maintenance of seed maturation and stamen development, but negatively controlled germination, growth and development of seedlings and flowering. In addition, the HbMFT1 promoter can be utilized in controlling transgene expression in stamens and seeds of rubber tree or other plant species. PMID:26950112

  5. Whole-transcriptome survey of the putative ATP-binding cassette (ABC) transporter family genes in the latex-producing laticifers of Hevea brasiliensis.

    PubMed

    Zhiyi, Nie; Guijuan, Kang; Yu, Li; Longjun, Dai; Rizhong, Zeng

    2015-01-01

    The ATP-binding cassette (ABC) proteins or transporters constitute a large protein family in plants and are involved in many different cellular functions and processes, including solute transportation, channel regulation and molecular switches, etc. Through transcriptome sequencing, a transcriptome-wide survey and expression analysis of the ABC protein genes were carried out using the laticiferous latex from Hevea brasiliensis (rubber tree). A total of 46 putative ABC family proteins were identified in the H. brasiliensis latex. These consisted of 12 'full-size', 21 'half-size' and 13 other putative ABC proteins, and all of them showed strong conservation with their Arabidopsis thaliana counterparts. This study indicated that all eight plant ABC protein paralog subfamilies were identified in the H. brasiliensis latex, of which ABCB, ABCG and ABCI were the most abundant. Real-time quantitative reverse transcription-polymerase chain reaction assays demonstrated that gene expression of several latex ABC proteins was regulated by ethylene, jasmonic acid or bark tapping (a wound stress) stimulation, and that HbABCB15, HbABCB19, HbABCD1 and HbABCG21 responded most significantly of all to the abiotic stresses. The identification and expression analysis of the latex ABC family proteins could facilitate further investigation into their physiological involvement in latex metabolism and rubber biosynthesis by H. brasiliensis.

  6. Whole-Transcriptome Survey of the Putative ATP-Binding Cassette (ABC) Transporter Family Genes in the Latex-Producing Laticifers of Hevea brasiliensis

    PubMed Central

    Zhiyi, Nie; Guijuan, Kang; Yu, Li; Longjun, Dai; Rizhong, Zeng

    2015-01-01

    The ATP-binding cassette (ABC) proteins or transporters constitute a large protein family in plants and are involved in many different cellular functions and processes, including solute transportation, channel regulation and molecular switches, etc. Through transcriptome sequencing, a transcriptome-wide survey and expression analysis of the ABC protein genes were carried out using the laticiferous latex from Hevea brasiliensis (rubber tree). A total of 46 putative ABC family proteins were identified in the H. brasiliensis latex. These consisted of 12 ‘full-size’, 21 ‘half-size’ and 13 other putative ABC proteins, and all of them showed strong conservation with their Arabidopsis thaliana counterparts. This study indicated that all eight plant ABC protein paralog subfamilies were identified in the H. brasiliensis latex, of which ABCB, ABCG and ABCI were the most abundant. Real-time quantitative reverse transcription-polymerase chain reaction assays demonstrated that gene expression of several latex ABC proteins was regulated by ethylene, jasmonic acid or bark tapping (a wound stress) stimulation, and that HbABCB15, HbABCB19, HbABCD1 and HbABCG21 responded most significantly of all to the abiotic stresses. The identification and expression analysis of the latex ABC family proteins could facilitate further investigation into their physiological involvement in latex metabolism and rubber biosynthesis by H. brasiliensis. PMID:25615936

  7. Identification and reconstitution of the rubber biosynthetic machinery on rubber particles from Hevea brasiliensis

    PubMed Central

    Yamashita, Satoshi; Yamaguchi, Haruhiko; Waki, Toshiyuki; Aoki, Yuichi; Mizuno, Makie; Yanbe, Fumihiro; Ishii, Tomoki; Funaki, Ayuta; Tozawa, Yuzuru; Miyagi-Inoue, Yukino; Fushihara, Kazuhisa; Nakayama, Toru; Takahashi, Seiji

    2016-01-01

    Natural rubber (NR) is stored in latex as rubber particles (RPs), rubber molecules surrounded by a lipid monolayer. Rubber transferase (RTase), the enzyme responsible for NR biosynthesis, is believed to be a member of the cis-prenyltransferase (cPT) family. However, none of the recombinant cPTs have shown RTase activity independently. We show that HRT1, a cPT from Heveabrasiliensis, exhibits distinct RTase activity in vitro only when it is introduced on detergent-washed HeveaRPs (WRPs) by a cell-free translation-coupled system. Using this system, a heterologous cPT from Lactucasativa also exhibited RTase activity, indicating proper introduction of cPT on RP is the key to reconstitute active RTase. RP proteomics and interaction network analyses revealed the formation of the protein complex consisting of HRT1, rubber elongation factor (REF) and HRT1-REF BRIDGING PROTEIN. The RTase activity enhancement observed for the complex assembled on WRPs indicates the HRT1-containing complex functions as the NR biosynthetic machinery. DOI: http://dx.doi.org/10.7554/eLife.19022.001 PMID:27790974

  8. Identification and reconstitution of the rubber biosynthetic machinery on rubber particles from Hevea brasiliensis.

    PubMed

    Yamashita, Satoshi; Yamaguchi, Haruhiko; Waki, Toshiyuki; Aoki, Yuichi; Mizuno, Makie; Yanbe, Fumihiro; Ishii, Tomoki; Funaki, Ayuta; Tozawa, Yuzuru; Miyagi-Inoue, Yukino; Fushihara, Kazuhisa; Nakayama, Toru; Takahashi, Seiji

    2016-10-28

    Natural rubber (NR) is stored in latex as rubber particles (RPs), rubber molecules surrounded by a lipid monolayer. Rubber transferase (RTase), the enzyme responsible for NR biosynthesis, is believed to be a member of the cis-prenyltransferase (cPT) family. However, none of the recombinant cPTs have shown RTase activity independently. We show that HRT1, a cPT from Heveabrasiliensis, exhibits distinct RTase activity in vitro only when it is introduced on detergent-washed HeveaRPs (WRPs) by a cell-free translation-coupled system. Using this system, a heterologous cPT from Lactucasativa also exhibited RTase activity, indicating proper introduction of cPT on RP is the key to reconstitute active RTase. RP proteomics and interaction network analyses revealed the formation of the protein complex consisting of HRT1, rubber elongation factor (REF) and HRT1-REF BRIDGING PROTEIN. The RTase activity enhancement observed for the complex assembled on WRPs indicates the HRT1-containing complex functions as the NR biosynthetic machinery.

  9. Genome-wide identification of rubber tree (Hevea brasiliensis Muell. Arg.) aquaporin genes and their response to ethephon stimulation in the laticifer, a rubber-producing tissue.

    PubMed

    Zou, Zhi; Gong, Jun; An, Feng; Xie, Guishui; Wang, Jikun; Mo, Yeyong; Yang, Lifu

    2015-11-25

    Natural rubber, an important industrial raw material, is specifically synthesized in laticifers located inside the rubber tree (Hevea brasiliensis Muell. Arg.) trunk. Due to the absence of plasmodesmata, the laticifer water balance is mediated by aquaporins (AQPs). However, to date, the characterization of H. brasiliensis AQPs (HbAQPs) is still in its infancy. In this study, 51 full-length AQP genes were identified from the rubber tree genome. The phylogenetic analysis assigned these AQPs to five subfamilies, including 15 plasma membrane intrinsic proteins (PIPs), 17 tonoplast intrinsic proteins (TIPs), 9 NOD26-like intrinsic proteins (NIPs), 4 small basic intrinsic proteins (SIPs) and 6 X intrinsic proteins (XIPs). Functional prediction based on the analysis of the aromatic/arginine (ar/R) selectivity filter, Froger's positions and specificity-determining positions (SDPs) showed a remarkable difference in substrate specificity among subfamilies. Homology analysis supported the expression of 44 HbAQP genes in at least one of the examined tissues. Furthermore, deep sequencing of the laticifer transcriptome in the form of latex revealed a key role of several PIP subfamily members in the laticifer water balance, and qRT-PCR analysis showed diverse expression patterns of laticifer-expressed HbAQP genes upon ethephon treatment, a widely-used practice for the stimulation of latex yield. This study provides an important genetic resource of HbAQP genes, which will be useful to improve the water use efficiency and latex yield of Hevea.

  10. Seasonal and clonal variations in technological and thermal properties of raw Hevea natural rubber

    USDA-ARS?s Scientific Manuscript database

    This study was undertaken over a ten-month period, under the environmental conditions within the state of Mato Grosso, Brazil, to evaluate the causes of variation in technological and thermal properties of raw natural rubber from different clones of Hevea brasiliensis (GT 1, PR 255, FX 3864 and RRIM...

  11. Genetic Determinism of Sensitivity to Corynespora cassiicola Exudates in Rubber Tree (Hevea brasiliensis)

    PubMed Central

    Tran, Dinh Minh; Clément-Demange, André; Déon, Marine; Garcia, Dominique; Le Guen, Vincent; Clément-Vidal, Anne; Soumahoro, Mouman; Masson, Aurélien; Label, Philippe; Le, Mau Tuy; Pujade-Renaud, Valérie

    2016-01-01

    An indirect phenotyping method was developed in order to estimate the susceptibility of rubber tree clonal varieties to Corynespora Leaf Fall (CLF) disease caused by the ascomycete Corynespora cassiicola. This method consists in quantifying the impact of fungal exudates on detached leaves by measuring the induced electrolyte leakage (EL%). The tested exudates were either crude culture filtrates from diverse C. cassiicola isolates or the purified cassiicolin (Cas1), a small secreted effector protein produced by the aggressive isolate CCP. The test was found to be quantitative, with the EL% response proportional to toxin concentration. For eight clones tested with two aggressive isolates, the EL% response to the filtrates positively correlated to the response induced by conidial inoculation. The toxicity test applied to 18 clones using 13 toxinic treatments evidenced an important variability among clones and treatments, with a significant additional clone x treatment interaction effect. A genetic linkage map was built using 306 microsatellite markers, from the F1 population of the PB260 x RRIM600 family. Phenotyping of the population for sensitivity to the purified Cas1 effector and to culture filtrates from seven C. cassiicola isolates revealed a polygenic determinism, with six QTL detected on five chromosomes and percentages of explained phenotypic variance varying from 11 to 17%. Two common QTL were identified for the CCP filtrate and the purified cassiicolin, suggesting that Cas1 may be the main effector of CCP filtrate toxicity. The CCP filtrate clearly contrasted with all other filtrates. The toxicity test based on Electrolyte Leakage Measurement offers the opportunity to assess the sensitivity of rubber genotypes to C. cassiicola exudates or purified effectors for genetic investigations and early selection, without risk of spreading the fungus in plantations. However, the power of this test for predicting field susceptibility of rubber clones to CLF will have

  12. Genetic Determinism of Sensitivity to Corynespora cassiicola Exudates in Rubber Tree (Hevea brasiliensis).

    PubMed

    Tran, Dinh Minh; Clément-Demange, André; Déon, Marine; Garcia, Dominique; Le Guen, Vincent; Clément-Vidal, Anne; Soumahoro, Mouman; Masson, Aurélien; Label, Philippe; Le, Mau Tuy; Pujade-Renaud, Valérie

    2016-01-01

    An indirect phenotyping method was developed in order to estimate the susceptibility of rubber tree clonal varieties to Corynespora Leaf Fall (CLF) disease caused by the ascomycete Corynespora cassiicola. This method consists in quantifying the impact of fungal exudates on detached leaves by measuring the induced electrolyte leakage (EL%). The tested exudates were either crude culture filtrates from diverse C. cassiicola isolates or the purified cassiicolin (Cas1), a small secreted effector protein produced by the aggressive isolate CCP. The test was found to be quantitative, with the EL% response proportional to toxin concentration. For eight clones tested with two aggressive isolates, the EL% response to the filtrates positively correlated to the response induced by conidial inoculation. The toxicity test applied to 18 clones using 13 toxinic treatments evidenced an important variability among clones and treatments, with a significant additional clone x treatment interaction effect. A genetic linkage map was built using 306 microsatellite markers, from the F1 population of the PB260 x RRIM600 family. Phenotyping of the population for sensitivity to the purified Cas1 effector and to culture filtrates from seven C. cassiicola isolates revealed a polygenic determinism, with six QTL detected on five chromosomes and percentages of explained phenotypic variance varying from 11 to 17%. Two common QTL were identified for the CCP filtrate and the purified cassiicolin, suggesting that Cas1 may be the main effector of CCP filtrate toxicity. The CCP filtrate clearly contrasted with all other filtrates. The toxicity test based on Electrolyte Leakage Measurement offers the opportunity to assess the sensitivity of rubber genotypes to C. cassiicola exudates or purified effectors for genetic investigations and early selection, without risk of spreading the fungus in plantations. However, the power of this test for predicting field susceptibility of rubber clones to CLF will have

  13. Carbon isotope composition of latex does not reflect temporal variations of photosynthetic carbon isotope discrimination in rubber trees (Hevea brasiliensis).

    PubMed

    Kanpanon, Nicha; Kasemsap, Poonpipope; Thaler, Philippe; Kositsup, Boonthida; Gay, Frédéric; Lacote, Régis; Epron, Daniel

    2015-11-01

    Latex, the cytoplasm of laticiferous cells localized in the inner bark of rubber trees (Hevea brasiliensis Müll. Arg.), is collected by tapping the bark. Following tapping, latex flows out of the trunk and is regenerated, whereas in untapped trees, there is no natural exudation. It is still unknown whether the carbohydrates used for latex regeneration in tapped trees is coming from recent photosynthates or from stored carbohydrates, and in the former case, it is expected that latex carbon isotope composition of tapped trees will vary seasonally, whereas latex isotope composition of untapped trees will be more stable. Temporal variations of carbon isotope composition of trunk latex (δ(13)C-L), leaf soluble compounds (δ(13)C-S) and bulk leaf material (δ(13)C-B) collected from tapped and untapped 20-year-old trees were compared. A marked difference in δ(13)C-L was observed between tapped and untapped trees whatever the season. Trunk latex from tapped trees was more depleted (1.6‰ on average) with more variable δ(13)C values than those of untapped trees. δ(13)C-L was higher and more stable across seasons than δ(13)C-S and δ(13)C-B, with a maximum seasonal difference of 0.7‰ for tapped trees and 0.3‰ for untapped trees. δ(13)C-B was lower in tapped than in untapped trees, increasing from August (middle of the rainy season) to April (end of the dry season). Differences in δ(13)C-L and δ(13)C-B between tapped and untapped trees indicated that tapping affects the metabolism of both laticiferous cells and leaves. The lack of correlation between δ(13)C-L and δ(13)C-S suggests that recent photosynthates are mixed in the large pool of stored carbohydrates that are involved in latex regeneration after tapping. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Evapotranspiration of rubber (Hevea brasiliensis) under the highly seasonal rainfall regime of the Asian monsoon in mainland Southeast Asia

    NASA Astrophysics Data System (ADS)

    Giambelluca, T. W.; Mudd, R. G.; Liu, W.; Kobayashi, N.; Ziegler, A. D.; Miyazawa, Y.; Kumagai, T.; Huang, M.

    2012-12-01

    The Asian Monsoon dominates the climate of the mainland Southeast Asia (MSEA) region, characterized by a highly seasonal rainfall regime in which 80-90% of annual rainfall occurs during the 6-month (May-October) wet season. The accompanying extremes in soil moisture, solar radiation, and vapor pressure deficit exert strong controls on ecosystem fluxes, including evapotranspiration (ET). Rubber (Hevea brasiliensis), the major commercial crop currently replacing traditional agriculture and secondary forests in MSEA is a native of the equatorial Amazon rainforest, and differs physiologically from the dominant native SE Asian forest tree species. It sheds its leaves in the middle of the dry season and flushes new leaves before the onset of the wet season. In some areas, rubber cultivation is suspected of having caused changes in local climate and watershed processes, including a dramatic downward trend in fog frequency and large increases in surface runoff and soil erosion (Wu et al., 2001, Int. J. Sust. Dev. World Ecol. 8:337-345). Guardiola-Claramonte et al. (2008, Ecohydrology 1:13-22; 2010, Ecohydrology 3:306-314) noted striking differences in the timing and rate of dry season root-water extraction under rubber as compared with other vegetation types. To investigate the environmental impacts of rubber, eddy covariance flux towers were installed to monitor energy, water, and carbon exchange at rubber plantation sites in northeastern Thailand and Cambodia. Results of the first two years of observations at the sites indicate that controls on ET differ between wet and dry seasons, with varying responses to energy, soil moisture, canopy wetness, and leaf area. Despite the long dry season and loss of leaves for several weeks, rubber accumulates exceptionally high annual ET totals, exceeding those of natural forest and other plant functional types in the region. The phenology of rubber represents a disruption of the land-atmosphere interactions of native and other non

  15. Identification of differentially expressed genes and signalling pathways in bark of Hevea brasiliensis seedlings associated with secondary laticifer differentiation using gene expression microarray.

    PubMed

    Loh, Swee Cheng; Thottathil, Gincy P; Othman, Ahmad Sofiman

    2016-10-01

    The natural rubber of Para rubber tree, Hevea brasiliensis, is the main crop involved in industrial rubber production due to its superior quality. The Hevea bark is commercially exploited to obtain latex, which is produced from the articulated secondary laticifer. The laticifer is well defined in the aspect of morphology; however, only some genes associated with its development have been reported. We successfully induced secondary laticifer in the jasmonic acid (JA)-treated and linolenic acid (LA)-treated Hevea bark but secondary laticifer is not observed in the ethephon (ET)-treated and untreated Hevea bark. In this study, we analysed 27,195 gene models using NimbleGen microarrays based on the Hevea draft genome. 491 filtered differentially expressed (FDE) transcripts that are common to both JA- and LA-treated bark samples but not ET-treated bark samples were identified. In the Eukaryotic Orthologous Group (KOG) analysis, 491 FDE transcripts belong to different functional categories that reflect the diverse processes and pathways involved in laticifer differentiation. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) and KOG analysis, the profile of the FDE transcripts suggest that JA- and LA-treated bark samples have a sufficient molecular basis for secondary laticifer differentiation, especially regarding secondary metabolites metabolism. FDE genes in this category are from the cytochrome (CYP) P450 family, ATP-binding cassette (ABC) transporter family, short-chain dehydrogenase/reductase (SDR) family, or cinnamyl alcohol dehydrogenase (CAD) family. The data includes many genes involved in cell division, cell wall synthesis, and cell differentiation. The most abundant transcript in FDE list was SDR65C, reflecting its importance in laticifer differentiation. Using the Basic Local Alignment Search Tool (BLAST) as part of annotation and functional prediction, several characterised as well as uncharacterized transcription factors and genes were found in the

  16. Expression Profiles, Characterization and Function of HbTCTP in Rubber Tree (Hevea brasiliensis)

    PubMed Central

    Deng, Zhi; Chen, Jiangshu; Leclercq, Julie; Zhou, Zhuangzhi; Liu, Changren; Liu, Hui; Yang, Hong; Montoro, Pascal; Xia, Zhihui; Li, Dejun

    2016-01-01

    As a highly conserved protein, the translationally controlled tumor protein (TCTP) carries out vital roles in various life processes. In rubber tree, two TCTP genes, HbTCTP and HbTCTP1, were cloned, but only HbTCTP1 was studied in details. In this study, cis-acting regulatory elements, expression patterns, subcellular localization, interacting proteins, and antioxidant activity of HbTCTP were systematically analyzed. Besides the common cis-acting regulatory elements, HbTCTP promoter also harbored various known cis-elements that respond to hormone/stresses. Being consistent with the aforementioned results, HbTCTP was regulated by drought, low temperature, high salt, ethylene (ET), wounding, H2O2, and methyl jasmonate (MeJA) treatments. HbTCTP was expressed throughout different tissues and developmental stages of leaves. In addition, HbTCTP was associated with tapping panel dryness (TPD). HbTCTP was localized in the membrane, cytoplasm and the nucleus, and interacted with four proteins rubber elongation factor (REF), 17.5 kDa heat shock family protein, annexin, and REF-like stress related protein 1. Being similar to HbTCTP1, HbTCTP also indicated antioxidant activity in metal-catalyzed oxidation (MCO) system. Our results are useful for further understanding the molecular characterization and expression profiles of HbTCTP, but also lay a solid foundation for elucidating the function of HbTCTP in rubber tree. PMID:27375647

  17. Comparative Analysis of Latex Transcriptome Reveals Putative Molecular Mechanisms Underlying Super Productivity of Hevea brasiliensis

    PubMed Central

    Li, Heping; Fan, Yujie; Yang, Jianghua; Qi, Jiyan; Li, Huibo

    2013-01-01

    Increasing demand for natural rubber prompts studies into the mechanisms governing the productivity of rubber tree (Heveabrasiliensis). It is very interesting to notice that a rubber tree of clone PR107 in Yunnan, China is reported to yield more than 20 times higher than the average rubber tree. This super-high-yielding (SHY) rubber tree (designated as SY107), produced 4.12 kg of latex (cytoplasm of rubber producing laticifers, containing about 30% of rubber) per tapping, more than 7-fold higher than that of the control. This rubber tree is therefore a good material to study how the rubber production is regulated at a molecular aspect. A comprehensive cDNA-AFLP transcript profiling was performed on the latex of SY107 and its average counterparts by using the 384 selective primer pairs for two restriction enzyme combinations (ApoI/MseI and TaqI/MseI). A total of 746 differentially expressed (DE) transcript-derived fragments (TDFs) were identified, of which the expression patterns of 453 TDFs were further confirmed by RT-PCR. These RT-PCR confirmed TDFs represented 352 non-redundant genes, of which 215 had known or partially known functions and were grouped into 10 functional categories. The top three largest categories were transcription and protein synthesis (representing 24.7% of the total genes), defense and stress (15.3%), and primary and secondary metabolism (14.0%). Detailed analysis of the DE-genes suggests notable characteristics of SHY phenotype in improved sucrose loading capability, rubber biosynthesis-preferred sugar utilization, enhanced general metabolism and timely stress alleviation. However, the SHY phenotype has little correlation with rubber-biosynthesis pathway genes. PMID:24066172

  18. Comparative analysis of latex transcriptome reveals putative molecular mechanisms underlying super productivity of Hevea brasiliensis.

    PubMed

    Tang, Chaorong; Xiao, Xiaohu; Li, Heping; Fan, Yujie; Yang, Jianghua; Qi, Jiyan; Li, Huibo

    2013-01-01

    Increasing demand for natural rubber prompts studies into the mechanisms governing the productivity of rubber tree (Heveabrasiliensis). It is very interesting to notice that a rubber tree of clone PR107 in Yunnan, China is reported to yield more than 20 times higher than the average rubber tree. This super-high-yielding (SHY) rubber tree (designated as SY107), produced 4.12 kg of latex (cytoplasm of rubber producing laticifers, containing about 30% of rubber) per tapping, more than 7-fold higher than that of the control. This rubber tree is therefore a good material to study how the rubber production is regulated at a molecular aspect. A comprehensive cDNA-AFLP transcript profiling was performed on the latex of SY107 and its average counterparts by using the 384 selective primer pairs for two restriction enzyme combinations (ApoI/MseI and TaqI/MseI). A total of 746 differentially expressed (DE) transcript-derived fragments (TDFs) were identified, of which the expression patterns of 453 TDFs were further confirmed by RT-PCR. These RT-PCR confirmed TDFs represented 352 non-redundant genes, of which 215 had known or partially known functions and were grouped into 10 functional categories. The top three largest categories were transcription and protein synthesis (representing 24.7% of the total genes), defense and stress (15.3%), and primary and secondary metabolism (14.0%). Detailed analysis of the DE-genes suggests notable characteristics of SHY phenotype in improved sucrose loading capability, rubber biosynthesis-preferred sugar utilization, enhanced general metabolism and timely stress alleviation. However, the SHY phenotype has little correlation with rubber-biosynthesis pathway genes.

  19. Applicability of Landsat TM data for inventorying and monitoring of rubber (Hevea brasiliensis) plantations in Selangor, Malaysia: Linkages to policies

    NASA Astrophysics Data System (ADS)

    Suratman, Mohd Nazip

    2003-06-01

    Rubber tree (Hevea brasiliensis (Wild ex Adr. De Juss) Muell Arg.) plantations in Malaysia are important sources of natural rubber and wood products. Effective management and appropriate policy for these resources require reliable information on resource dynamics and forecasts of resource availability. The need for inventories and monitoring systems prompted this research into utilising ground information and satellite imagery for developing methods for forest plantation inventory. Monitoring procedures were developed using three dates of Landsat Thematic Mapper (TM) imagery. The specific objectives of the research were: (1) to develop an effective method for inventorying rubber tree plantations using an appropriate combination of satellite imagery and ground sampling in the State of Selangor, Malaysia; (2) to demonstrate the application of a Landsat TM-based rubber volume model in an extended area of rubber plantations south of Kuala Lumpur (KL), Malaysia; (3) to develop an operational methodology for monitoring land use/cover change, with a primary focus on rubber plantations; and (4) to identify relationships between the primary drivers of resource change and policies, and examine the evidence of policies---rubber area change linkages in the study area. Reasonably accurate predictions of the volume, age, and area of rubber plantations were obtained from Landsat TM data. The use of supervised image classification and an image segmentation approach for rubber volume model application showed better performance for volume prediction than a combined land use/cover and rubber volume classification technique, thus providing a useful tool for displaying rubber stand volume within segments or spatial units across the landscape. The combined use of a time series of Landsat TM imagery, modified postclassification change detection, and geographic information system (GIS) techniques made it possible to produce land use/cover change matrices and rubber area change information

  20. Involvement of HbPIP2;1 and HbTIP1;1 aquaporins in ethylene stimulation of latex yield through regulation of water exchanges between inner liber and latex cells in Hevea brasiliensis.

    PubMed

    Tungngoen, Kessarin; Kongsawadworakul, Panida; Viboonjun, Unchera; Katsuhara, Maki; Brunel, Nicole; Sakr, Soulaiman; Narangajavana, Jarunya; Chrestin, Hervé

    2009-10-01

    Natural rubber is synthesized in specialized articulated cells (laticifers) located in the inner liber of Hevea brasiliensis. Upon bark tapping, the laticifer cytoplasm (latex) is expelled due to liber tissue turgor pressure. In mature virgin (untapped) trees, short-term kinetic studies confirmed that ethylene, the rubber yield stimulant used worldwide, increased latex yield, with a concomitant decrease in latex total solid content, probably through water influx in the laticifers. As the mature laticifers are devoid of plasmodesmata, the rapid water exchanges with surrounding liber cells probably occur via the aquaporin pathway. Two full-length aquaporin cDNAs (HbPIP2;1 and HbTIP1;1, for plasma membrane intrinsic protein and tonoplast intrinsic protein, respectively) were cloned and characterized. The higher efficiency of HbPIP2;1 than HbTIP1;1 in increasing plasmalemma water conductance was verified in Xenopus laevis oocytes. HbPIP2;1 was insensitive to HgCl(2). In situ hybridization demonstrated that HbPIP2;1 was expressed in all liber tissues in the young stem, including the laticifers. HbPIP2;1 was up-regulated in both liber tissues and laticifers, whereas HbTIP1;1 was down-regulated in liber tissues but up-regulated in laticifers in response to bark Ethrel treatment. Ethylene-induced HbPIP2;1 up-regulation was confirmed by western-blot analysis. The promoter sequences of both genes were cloned and found to harbor, among many others, ethylene-responsive and other chemical-responsive (auxin, copper, and sulfur) elements known to increase latex yield. Increase in latex yield in response to ethylene was emphasized to be linked with water circulation between the laticifers and their surrounding tissues as well as with the probable maintenance of liber tissue turgor, which together favor prolongation of latex flow.

  1. The cyanogenic syndrome in rubber tree Hevea brasiliensis: tissue-damage-dependent activation of linamarase and hydroxynitrile lyase accelerates hydrogen cyanide release

    PubMed Central

    Kadow, Daniel; Voß, Karsten; Selmar, Dirk; Lieberei, Reinhard

    2012-01-01

    Background and Aims The release of hydrogen cyanide (HCN) from injured plant tissue affects multiple ecological interactions. Plant-derived HCN can act as a defence against herbivores and also plays an important role in plant–pathogen interactions. Crucial for activity as a feeding deterrent is the amount of HCN generated per unit time, referred to as cyanogenic capacity (HCNc). Strong intraspecific variation in HCNc has been observed among cyanogenic plants. This variation, in addition to genotypic variability (e.g. in Trifolium repens), can result from modifications in the expression level of the enzymes involved in either cyanogenic precursor formation or HCN release (as seen in Sorghum bicolor and Phaseolus lunatus). Thus, a modification or modulation of HCNc in reaction to the environment can only be achieved from one to the next generation when under genetic control and within days or hours when transcriptional regulations are involved. In the present study, it is shown that in rubber tree (Hevea brasiliensis) HCNc is modulated by post-translational activity regulation of the key enzymes for cyanide release. Methods Linamarase (LIN) and hydroxynitrile lyase (HNL) activity was determined by colorimetric assays utilizing dissociation of the substrates p-nitrophenyl-β-d-glucopyranoside and acetone cyanohydrin, respectively. Key Results In rubber tree leaves, LIN and HNL show up to ten-fold increased activity in response to tissue damage. This enzyme activation occurs within seconds and results in accelerated HCN formation. It is restricted to the damaged leaf area and depends on the severity of tissue damage. Conclusions LIN and HNL activation (in contrast to genetic and transcriptional regulations) allows an immediate, local and damage type-dependent modulation of the cyanogenic response. Accordingly, this post-translational activation plays a decisive role in the defence of H. brasiliensis against herbivores as well as pathogens and may allow more flexible

  2. Evapotranspiration of rubber ( Hevea brasiliensis ) cultivated at two plantation sites in Southeast Asia: RUBBER EVAPOTRANSPIRATION IN SE ASIA

    SciTech Connect

    Giambelluca, Thomas W.; Mudd, Ryan G.; Liu, Wen; Ziegler, Alan D.; Kobayashi, Nakako; Kumagai, Tomo'omi; Miyazawa, Yoshiyuki; Lim, Tiva Khan; Huang, Maoyi; Fox, Jefferson; Yin, Song; Mak, Sophea Veasna; Kasemsap, Poonpipope

    2016-02-01

    The expansion of rubber (Hevea brasiliensis) cultivation to higher latitudes and higher elevations in southeast Asia is part of a dramatic shift in the direction of rural land cover change in the region toward more tree covered landscapes. To investigate the possible effects of increasing rubber cultivation in the region on ecosystem services including water cycling, eddy covariance towers were established to measure ecosystem fluxes within two rubber plantations, one each in Bueng Kan, northeastern Thailand, and Kampong Cham, central Cambodia. The results show that evapotranspiration (ET) at both sites is strongly related to variations in available energy and leaf area, and moderately controlled by soil moisture. Measured mean annual ET was 1128 and 1272 mm for the Thailand and Cambodia sites, respectively. After adjustment for energy closure, mean annual was estimated to be 1211 and 1459 mm yr at the Thailand and Cambodia sites, respectively. Based on these estimates and that of another site in Xishuangbanna, southwestern China, it appears that of rubber is higher than that of other tree dominated land covers in the region, including forest. While measurements by others in non rubber tropical ecosystems indicate that at high net radiation sites is at most only slightly higher than for sites with lower net radiation, mean annual rubber increases strongl with increasing net radiation across the three available rubber plantation observation sites. With the continued expansion of tree dominated land covers, including rubber cultivation, in southeast Asia, the possible association between commercially viable, fast growing tree crop species Giambelluca et al. Evapotranspiration of rubber (Havea brasiliensis) cultivated at two sites in southeast Asia and their relatively high water use raises concerns about potential effects on water and food security.

  3. The control by delta mu H+ of the tonoplast-bound H+-translocating adenosine triphosphatase from rubber-tree (Hevea brasiliensis) latex.

    PubMed Central

    Marin, B P

    1985-01-01

    The relationship between tonoplast-bound ATPase activity and the magnitude of the electrochemical proton gradient has been investigated on tightly sealed vesicles prepared from rubber-tree (Hevea brasiliensis) latex. A variety of methods have been used to modify, either alone or together, the two components of the electrochemical proton gradient (delta mu H+). When the delta pH component was decreased either by titration with (NH4)2SO4 or by addition of protonophores or nigericin in the presence of K+, ATPase activity was stimulated. On the other hand, when the delta psi component was decreased either by addition of lipophilic cations or by addition of valinomycin in the presence of K+, ATPase activity decreased. It is concluded that activity of the tonoplast-bound ATPase is regulated by changes in the electrochemical proton gradient across the tonoplast, so that, once the maximum proton gradient is established across the tonoplast, any perturbation of the equilibrium state should result in the increased rate of ATP hydrolysis as the enzyme attempts to re-establish the initial gradient. PMID:2994636

  4. Simulation of Canopy CO2/H2O Fluxes for a Rubber (Hevea Brasiliensis) Plantation in Central Cambodia: The Effect of the Regular Spacing of Planted Trees

    SciTech Connect

    Kumagai, Tomo'omi; Mudd, Ryan; Miyazawa, Yoshiyuki; Liu, Wen; Giambelluca, Thomas; Kobayashi, N.; Lim, Tiva Khan; Jomura, Mayuko; Matsumoto, Kazuho; Huang, Maoyi; Chen, Qi; Ziegler, Alan; Yin, Song

    2013-09-10

    We developed a soil-vegetation-atmosphere transfer (SVAT) model applicable to simulating CO2 and H2O fluxes from the canopies of rubber plantations, which are characterized by distinct canopy clumping produced by regular spacing of plantation trees. Rubber (Hevea brasiliensis Müll. Arg.) plantations, which are rapidly expanding into both climatically optimal and sub-optimal environments throughout mainland Southeast Asia, potentially change the partitioning of water, energy, and carbon at multiple scales, compared with traditional land covers it is replacing. Describing the biosphere-atmosphere exchange in rubber plantations via SVAT modeling is therefore essential to understanding the impacts on environmental processes. The regular spacing of plantation trees creates a peculiar canopy structure that is not well represented in most SVAT models, which generally assumes a non-uniform spacing of vegetation. Herein we develop a SVAT model applicable to rubber plantation and an evaluation method for its canopy structure, and examine how the peculiar canopy structure of rubber plantations affects canopy CO2 and H2O exchanges. Model results are compared with measurements collected at a field site in central Cambodia. Our findings suggest that it is crucial to account for intensive canopy clumping in order to reproduce observed rubber plantation fluxes. These results suggest a potentially optimal spacing of rubber trees to produce high productivity and water use efficiency.

  5. Evidence for an Amiloride-Inhibited Mg2+/2H+ Antiporter in Lutoid (Vacuolar) Vesicles from Latex of Hevea brasiliensis1

    PubMed Central

    Amalou, Zakia; Gibrat, Rémy; Brugidou, Christophe; Trouslot, Pierre; d'Auzac, Jean

    1992-01-01

    Lutoids represent a lysosomal microvacuolar compartment of rubber-tree (Hevea brasiliensis) latex. We observed acidification of isolated vesicles after imposing an outward Mg2+ diffusion gradient and dissipation of a preformed pH gradient in the presence of exogenous Mg2+. These results suggest the presence of a Mg2+/H+ antiporter. The maximum Mg2+/H+ exchange rate was observed at pH 8.5. The Km values for Mg2+ (2.6 mm) were identical for both influx and efflux experiments. When membrane potential was clamped at zero with K+ and valinomycin, the response of the membrane potential probe oxonol VI showed that the Mg2+/H+ exchange was electroneutral. Mg2+/H+ exchange was inhibited by amiloride and imipramine. Both the inhibiting concentration range and the Km for Mg2+ are similar to those reported for the Mg2+/2Na+ antiporter in animals cell. These data are consistent with the existence of a Mg2+/2H+ antiporter in a plant tonoplast. PMID:16652955

  6. Isolation of a furan fatty acid from Hevea brasiliensis latex employing the combined use of pH-zone-refining and conventional countercurrent chromatography.

    PubMed

    Englert, Michael; Ulms, Kerstin; Wendlinger, Christine; Vetter, Walter

    2016-02-01

    Furan fatty acids are valuable and bioactive minor fatty acids that usually contribute <0.1% to the fatty acid content of food samples. Their biological role still remains unclear as authentic furan fatty acid standards are not readily available and thorough experimental studies verifying the relevance of furan fatty acids are thus virtually impossible. An efficient protocol for the isolation of the furan fatty acid 9-(3-methyl-5-pentylfuran-2-yl)-nonanoic acid from hydrolyzed and centrifuged latex of Hevea brasiliensis was developed using countercurrent chromatography. A first run using pH-zone-refining countercurrent chromatography provided 48.4 mg of 9-(3-methyl-5-pentylfuran-2-yl)-nonanoic acid from 210 mg latex extract in a purity of 95%. The purity was increased to 99% by means of one second run in conventional countercurrent chromatography mode. The Structure and purity of 9-(3-methyl-5-pentylfuran-2-yl)-nonanoic acid were determined by gas chromatography coupled to mass spectrometry and (1)H and (13)C NMR spectroscopy.

  7. A method for protein extraction from different subcellular fractions of laticifer latex in Hevea brasiliensis compatible with 2-DE and MS

    PubMed Central

    2010-01-01

    Background Proteomic analysis of laticifer latex in Hevea brasiliensis has been received more significant attentions. However, the sticky and viscous characteristic of rubber latex as cytoplasm of laticifer cells and the complication of laticifer latex membrane systems has made it challenge to isolate high-quality proteins for 2-DE and MS. Results Based on the reported Borax/PVPP/Phenol (BPP) protocol, we developed an efficient method for protein preparation from different latex subcellular fractions and constructed high-resolution reference 2-DE maps. The obtained proteins from both total latex and C-serum fraction with this protocol generate more than one thousand protein spots and several hundreds of protein spots from rubber particles as well as lutoid fraction and its membranes on the CBB stained 2-DE gels. The identification of 13 representative proteins on 2-DE gels by MALDI TOF/TOF MS/MS suggested that this method is compatible with MS. Conclusion The proteins extracted by this method are compatible with 2-DE and MS. This protein preparation protocol is expected to be used in future comparative proteomic analysis for natural rubber latex. PMID:20565811

  8. Structural analysis of the endogenous glycoallergen Hev b 2 (endo-β-1,3-glucanase) from Hevea brasiliensis and its recognition by human basophils.

    PubMed

    Rodríguez-Romero, Adela; Hernández-Santoyo, Alejandra; Fuentes-Silva, Deyanira; Palomares, Laura A; Muñoz-Cruz, Samira; Yépez-Mulia, Lilian; Orozco-Martínez, Socorro

    2014-02-01

    Endogenous glycosylated Hev b 2 (endo-β-1,3-glucanase) from Hevea brasiliensis is an important latex allergen that is recognized by IgE antibodies from patients who suffer from latex allergy. The carbohydrate moieties of Hev b 2 constitute a potentially important IgE-binding epitope that could be responsible for its cross-reactivity. Here, the structure of the endogenous isoform II of Hev b 2 that exhibits three post-translational modifications, including an N-terminal pyroglutamate and two glycosylation sites at Asn27 and at Asn314, is reported from two crystal polymorphs. These modifications form a patch on the surface of the molecule that is proposed to be one of the binding sites for IgE. A structure is also proposed for the most important N-glycan present in this protein as determined by digestion with specific enzymes. To analyze the role of the carbohydrate moieties in IgE antibody binding and in human basophil activation, the glycoallergen was enzymatically deglycosylated and evaluated. Time-lapse automated video microscopy of basophils stimulated with glycosylated Hev b 2 revealed basophil activation and degranulation. Immunological studies suggested that carbohydrates on Hev b 2 represent an allergenic IgE epitope. In addition, a dimer was found in each asymmetric unit that may reflect a regulatory mechanism of this plant defence protein.

  9. Structural analysis of the endogenous glycoallergen Hev b 2 (endo-β-1,3-glucanase) from Hevea brasiliensis and its recognition by human basophils

    PubMed Central

    Rodríguez-Romero, Adela; Hernández-Santoyo, Alejandra; Fuentes-Silva, Deyanira; Palomares, Laura A.; Muñoz-Cruz, Samira; Yépez-Mulia, Lilian; Orozco-Martínez, Socorro

    2014-01-01

    Endogenous glycosylated Hev b 2 (endo-β-1,3-glucanase) from Hevea brasiliensis is an important latex allergen that is recognized by IgE antibodies from patients who suffer from latex allergy. The carbohydrate moieties of Hev b 2 constitute a potentially important IgE-binding epitope that could be responsible for its cross-reactivity. Here, the structure of the endogenous isoform II of Hev b 2 that exhibits three post-translational modifications, including an N-terminal pyro­glutamate and two glycosylation sites at Asn27 and at Asn314, is reported from two crystal polymorphs. These modifications form a patch on the surface of the molecule that is proposed to be one of the binding sites for IgE. A structure is also proposed for the most important N-glycan present in this protein as determined by digestion with specific enzymes. To analyze the role of the carbohydrate moieties in IgE antibody binding and in human basophil activation, the glycoallergen was enzymatically deglycosylated and evaluated. Time-lapse automated video microscopy of basophils stimulated with glycosylated Hev b 2 revealed basophil activation and degranulation. Immunological studies suggested that carbohydrates on Hev b 2 represent an allergenic IgE epitope. In addition, a dimer was found in each asymmetric unit that may reflect a regulatory mechanism of this plant defence protein. PMID:24531467

  10. Cloning and nucleotide sequence of a specific DNA fragment from Paracoccidioides brasiliensis.

    PubMed Central

    Goldani, L Z; Maia, A L; Sugar, A M

    1995-01-01

    We cloned and sequenced a species-specific 110-bp DNA fragment from Paracoccidioides brasiliensis. The DNA fragment was generated by PCR with primers complementary to the rat beta-actin gene under a low annealing temperature. Comparison of the nucleotide sequence, after excluding the primers, with those in the GenBank database identified approximately 60% homology with an exon of a major surface glycoprotein gene from Pneumocystis carinii and a fragment of unknown function in Saccharomyces cerevisiae chromosome VIII. By Southern hybridization analysis, the 32P-labelled fragment detected 1.0- and 1.9-kb restriction fragments within whole-cell genomic DNA of P. brasiliensis digested with HindIII and PstI, respectively, but failed to hybridize to genomic DNAs from Candida albicans, Blastomyces dermatitidis, Cryptococcus neoformans, Aspergillus fumigatus, Saccharomyces cerevisiae, Pneumocystis carinii, rat tissue, or humans under low-stringency hybridization conditions. Additionally, the specific DNA fragment from three different P. brasiliensis isolates (Pb18, RP18, RP17) was amplified by PCR with primers mostly complementary to nonactin sequences of the 110-bp DNA fragment. In contrast, there were no amplified products from other fungus genomic DNAs previously tested, including Histoplasma capsulatum. To date, this is the first species-specific DNA fragment cloned from P. brasiliensis which might be useful as a diagnostic marker for the identification and classification of different P. brasiliensis isolates. PMID:7650207

  11. Cloning and nucleotide sequence of a specific DNA fragment from Paracoccidioides brasiliensis.

    PubMed

    Goldani, L Z; Maia, A L; Sugar, A M

    1995-06-01

    We cloned and sequenced a species-specific 110-bp DNA fragment from Paracoccidioides brasiliensis. The DNA fragment was generated by PCR with primers complementary to the rat beta-actin gene under a low annealing temperature. Comparison of the nucleotide sequence, after excluding the primers, with those in the GenBank database identified approximately 60% homology with an exon of a major surface glycoprotein gene from Pneumocystis carinii and a fragment of unknown function in Saccharomyces cerevisiae chromosome VIII. By Southern hybridization analysis, the 32P-labelled fragment detected 1.0- and 1.9-kb restriction fragments within whole-cell genomic DNA of P. brasiliensis digested with HindIII and PstI, respectively, but failed to hybridize to genomic DNAs from Candida albicans, Blastomyces dermatitidis, Cryptococcus neoformans, Aspergillus fumigatus, Saccharomyces cerevisiae, Pneumocystis carinii, rat tissue, or humans under low-stringency hybridization conditions. Additionally, the specific DNA fragment from three different P. brasiliensis isolates (Pb18, RP18, RP17) was amplified by PCR with primers mostly complementary to nonactin sequences of the 110-bp DNA fragment. In contrast, there were no amplified products from other fungus genomic DNAs previously tested, including Histoplasma capsulatum. To date, this is the first species-specific DNA fragment cloned from P. brasiliensis which might be useful as a diagnostic marker for the identification and classification of different P. brasiliensis isolates.

  12. Molecular identification and characterization of a gene associated with the onset of tapping panel dryness (TPD) syndrome in rubber tree (Hevea brasiliensis Muell.) by mRNA differential display.

    PubMed

    Venkatachalam, Perumal; Thulaseedharan, Arjunan; Raghothama, Kashchandra

    2009-01-01

    In rubber tree (Hevea brasiliensis), tapping panel dryness (TPD) syndrome is considered as a complex physiological disorder which affects latex biosynthesis. To identify differentially expressed genes between healthy and TPD-affected trees, mRNA differential display reverse transcriptase polymerase chain reaction (DDRT-PCR) analysis was performed. We isolated 10 differentially expressed cDNA fragments of which one cDNA encoding a putative TOM20 like protein was identified. The cDNA (1,024 bp), corresponding to the HbTOM20 gene (H evea b rasiliensis Translocase of the Outer Mitochondrial Membrane), contained an open reading frame to code for 202 amino acid protein with a theoretical pI value of 9.5 and the calculated protein M (W) was 23.5 kDa. The predicted amino acid sequence contained conserved domains of TOM20 like proteins in the N-terminal. The protein HbTOM20 has 32% and 27% similarity to Populus TOM20 and Solanum TOM20, respectively. Both semi-quantitative RT-PCR and Northern blot results revealed that the HbTOM20 expression was significantly down-regulated in TPD-affected trees compared to healthy one. Accumulation of HbTOM20 mRNA transcripts was significantly higher in the bark tissues collected from healthy region than that of partially affected by TPD (partially dried) while barely detectable in completely TPD-affected area. Differential expression pattern was noticed in three rubber clones representing various degrees of TPD tolerance. These results suggest that down-regulation of HbTOM20 in TPD-affected trees may play an important role in alteration of mitochondrial metabolism resulting in impaired latex biosynthesis.

  13. Structural analysis of the endogenous glycoallergen Hev b 2 (endo-β-1,3-glucanase) from Hevea brasiliensis and its recognition by human basophils

    SciTech Connect

    Rodríguez-Romero, Adela Hernández-Santoyo, Alejandra; Fuentes-Silva, Deyanira; Palomares, Laura A.; Muñoz-Cruz, Samira; Yépez-Mulia, Lilian; Orozco-Martínez, Socorro

    2014-02-01

    This study describes the three-dimensional structure of the endogenous glycosylated allergen Hev b 2 (endo-β-1,3-glucanase), which exhibits three post-translational modifications that form a patch on the surface of the molecule that is proposed to be an allergenic IgE epitope. Endogenous glycosylated Hev b 2 (endo-β-1,3-glucanase) from Hevea brasiliensis is an important latex allergen that is recognized by IgE antibodies from patients who suffer from latex allergy. The carbohydrate moieties of Hev b 2 constitute a potentially important IgE-binding epitope that could be responsible for its cross-reactivity. Here, the structure of the endogenous isoform II of Hev b 2 that exhibits three post-translational modifications, including an N-terminal pyroglutamate and two glycosylation sites at Asn27 and at Asn314, is reported from two crystal polymorphs. These modifications form a patch on the surface of the molecule that is proposed to be one of the binding sites for IgE. A structure is also proposed for the most important N-glycan present in this protein as determined by digestion with specific enzymes. To analyze the role of the carbohydrate moieties in IgE antibody binding and in human basophil activation, the glycoallergen was enzymatically deglycosylated and evaluated. Time-lapse automated video microscopy of basophils stimulated with glycosylated Hev b 2 revealed basophil activation and degranulation. Immunological studies suggested that carbohydrates on Hev b 2 represent an allergenic IgE epitope. In addition, a dimer was found in each asymmetric unit that may reflect a regulatory mechanism of this plant defence protein.

  14. Influence of low-level laser associated with osteogenic proteins recombinant human BMP-2 and Hevea brasiliensis on bone repair in Wistar rats.

    PubMed

    Iyomasa, Mamie Mizusaki; Issa, João Paulo Mardegan; de Queiróz Tavares, Mirella Lemos; Pereira, Yamba Carla Lara; Stuani, Maria Bernadete Sasso; Mishima, Fabíola; Coutinho-Netto, Joaquim; Sebald, Walter

    2012-02-01

    This study analyzed the newly formed bone tissue after application of recombinant human BMP-2 (rhBMP-2) and P-1 (extracted from Hevea brasiliensis) proteins, 2 weeks after the creation of a critical bone defect in male Wistar rats treated or not with a low-intensity laser (GaAlAs 780 nm, 60 mW of power, and energy density dose of 30 J/cm(2)). The animals were divided into two major groups: (1) bone defect plus low-intensity laser treatment and (2) bone defect without laser irradiation. The following subgroups were also analyzed: (a) 5 μg of pure rhBMP-2; (b) 5 μg of pure P-1 fraction; (c) 5 μg of rhBMP-2/monoolein gel; (d) 5 μg of P-1 fraction/monoolein gel; (e) pure monoolein gel. Comparisons of the groups receiving laser treatment with those that did not receive laser irradiation show differences in the areas of new bone tissue. The group treated with 5 μg of rhBMP-2 and laser irradiation was not significantly different (P >0.05) than the nonirradiated group that received the same treatment. The irradiated, rhBMP-2/monoolein gel treatment group showed a lower area of bone formation than the nonirradiated, rhBMP-2/gel monoolein treatment group (P < 0.001). The area of new bone tissue in the other nonirradiated and irradiated groups was not significantly different (P > 0.05). Furthermore, the group that received the 5 μg of rhBMP-2 application showed the greatest bone formation. We conclude that the laser treatment did not interfere with the area of new bone tissue growth and that the greatest stimulus for bone formation involved application of the rhBMP-2 protein. Copyright © 2011 Wiley Periodicals, Inc.

  15. Construction of a high-density integrated genetic linkage map of rubber tree (Hevea brasiliensis) using genotyping-by-sequencing (GBS).

    PubMed

    Pootakham, Wirulda; Ruang-Areerate, Panthita; Jomchai, Nukoon; Sonthirod, Chutima; Sangsrakru, Duangjai; Yoocha, Thippawan; Theerawattanasuk, Kanikar; Nirapathpongporn, Kanlaya; Romruensukharom, Phayao; Tragoonrung, Somvong; Tangphatsornruang, Sithichoke

    2015-01-01

    Construction of linkage maps is crucial for genetic studies and marker-assisted breeding programs. Recent advances in next generation sequencing technologies allow for the generation of high-density linkage maps, especially in non-model species lacking extensive genomic resources. Here, we constructed a high-density integrated genetic linkage map of rubber tree (Hevea brasiliensis), the sole commercial producer of high-quality natural rubber. We applied a genotyping-by-sequencing (GBS) technique to simultaneously discover and genotype single nucleotide polymorphism (SNP) markers in two rubber tree populations. A total of 21,353 single nucleotide substitutions were identified, 55% of which represented transition events. GBS-based genetic maps of populations P and C comprised 1704 and 1719 markers and encompassed 2041 cM and 1874 cM, respectively. The average marker densities of these two maps were one SNP in 1.23-1.25 cM. A total of 1114 shared SNP markers were used to merge the two component maps. An integrated linkage map consisted of 2321 markers and spanned the cumulative length of 2052 cM. The composite map showed a substantial improvement in marker density, with one SNP marker in every 0.89 cM. To our knowledge, this is the most saturated genetic map in rubber tree to date. This integrated map allowed us to anchor 28,965 contigs, covering 135 Mb or 12% of the published rubber tree genome. We demonstrated that GBS is a robust and cost-effective approach for generating a common set of genome-wide SNP data suitable for constructing integrated linkage maps from multiple populations in a highly heterozygous agricultural species.

  16. Construction of a high-density integrated genetic linkage map of rubber tree (Hevea brasiliensis) using genotyping-by-sequencing (GBS)

    PubMed Central

    Pootakham, Wirulda; Ruang-Areerate, Panthita; Jomchai, Nukoon; Sonthirod, Chutima; Sangsrakru, Duangjai; Yoocha, Thippawan; Theerawattanasuk, Kanikar; Nirapathpongporn, Kanlaya; Romruensukharom, Phayao; Tragoonrung, Somvong; Tangphatsornruang, Sithichoke

    2015-01-01

    Construction of linkage maps is crucial for genetic studies and marker-assisted breeding programs. Recent advances in next generation sequencing technologies allow for the generation of high-density linkage maps, especially in non-model species lacking extensive genomic resources. Here, we constructed a high-density integrated genetic linkage map of rubber tree (Hevea brasiliensis), the sole commercial producer of high-quality natural rubber. We applied a genotyping-by-sequencing (GBS) technique to simultaneously discover and genotype single nucleotide polymorphism (SNP) markers in two rubber tree populations. A total of 21,353 single nucleotide substitutions were identified, 55% of which represented transition events. GBS-based genetic maps of populations P and C comprised 1704 and 1719 markers and encompassed 2041 cM and 1874 cM, respectively. The average marker densities of these two maps were one SNP in 1.23–1.25 cM. A total of 1114 shared SNP markers were used to merge the two component maps. An integrated linkage map consisted of 2321 markers and spanned the cumulative length of 2052 cM. The composite map showed a substantial improvement in marker density, with one SNP marker in every 0.89 cM. To our knowledge, this is the most saturated genetic map in rubber tree to date. This integrated map allowed us to anchor 28,965 contigs, covering 135 Mb or 12% of the published rubber tree genome. We demonstrated that GBS is a robust and cost-effective approach for generating a common set of genome-wide SNP data suitable for constructing integrated linkage maps from multiple populations in a highly heterozygous agricultural species. PMID:26074933

  17. Genome-Wide Identification of Jatropha curcas Aquaporin Genes and the Comparative Analysis Provides Insights into the Gene Family Expansion and Evolution in Hevea brasiliensis

    PubMed Central

    Zou, Zhi; Yang, Lifu; Gong, Jun; Mo, Yeyong; Wang, Jikun; Cao, Jianhua; An, Feng; Xie, Guishui

    2016-01-01

    Aquaporins (AQPs) are channel-forming integral membrane proteins that transport water and other small solutes across biological membranes. Despite the vital role of AQPs, to date, little is known in physic nut (Jatropha curcas L., Euphorbiaceae), an important non-edible oilseed crop with great potential for the production of biodiesel. In this study, 32 AQP genes were identified from the physic nut genome and the family number is relatively small in comparison to 51 in another Euphorbiaceae plant, rubber tree (Hevea brasiliensis Muell. Arg.). Based on the phylogenetic analysis, the JcAQPs were assigned to five subfamilies, i.e., nine plasma membrane intrinsic proteins (PIPs), nine tonoplast intrinsic proteins (TIPs), eight NOD26-like intrinsic proteins (NIPs), two X intrinsic proteins (XIPs), and four small basic intrinsic proteins (SIPs). Like rubber tree and other plant species, functional prediction based on the aromatic/arginine selectivity filter, Froger's positions, and specificity-determining positions showed a remarkable difference in substrate specificity among subfamilies of JcAQPs. Genome-wide comparative analysis revealed the specific expansion of PIP and TIP subfamilies in rubber tree and the specific gene loss of the XIP subfamily in physic nut. Furthermore, by analyzing deep transcriptome sequencing data, the expression evolution especially the expression divergence of duplicated HbAQP genes was also investigated and discussed. Results obtained from this study not only provide valuable information for future functional analysis and utilization of Jc/HbAQP genes, but also provide a useful reference to survey the gene family expansion and evolution in Euphorbiaceae plants and other plant species. PMID:27066041

  18. Leaf-, panel- and latex-expressed sequenced tags from the rubber tree (Hevea brasiliensis) under cold-stressed and suboptimal growing conditions: the development of gene-targeted functional markers for stress response.

    PubMed

    Silva, Carla C; Mantello, Camila C; Campos, Tatiana; Souza, Livia M; Gonçalves, Paulo S; Souza, Anete P

    2014-01-01

    Hevea brasiliensis is a native species of the Amazon Basin of South America and the primary source of natural rubber worldwide. Due to the occurrence of South American Leaf Blight disease in this area, rubber plantations have been extended to suboptimal regions. Rubber tree breeding is time-consuming and expensive, but molecular markers can serve as a tool for early evaluation, thus reducing time and costs. In this work, we constructed six different cDNA libraries with the aim of developing gene-targeted molecular markers for the rubber tree. A total of 8,263 reads were assembled, generating 5,025 unigenes that were analyzed; 912 expressed sequence tags (ESTs) represented new transcripts, and two sequences were highly up-regulated by cold stress. These unigenes were scanned for microsatellite (SSR) regions and single nucleotide polymorphisms (SNPs). In total, 169 novel EST-SSR markers were developed; 138 loci were polymorphic in the rubber tree, and 98 % presented transferability to six other Hevea species. Locus duplication was observed in H. brasiliensis and other species. Additionally, 43 SNP markers in 13 sequences that showed similarity to proteins involved in stress response, latex biosynthesis and developmental processes were characterized. cDNA libraries are a rich source of SSR and SNP markers and enable the identification of new transcripts. The new markers developed here will be a valuable resource for linkage mapping, QTL identification and other studies in the rubber tree and can also be used to evaluate the genetic variability of other Hevea species, which are valuable assets in rubber tree breeding.

  19. Hormonal treatment of the bark of rubber trees (Hevea brasiliensis) increases latex yield through latex dilution in relation with the differential expression of two aquaporin genes.

    PubMed

    Tungngoen, Kessarin; Viboonjun, Unchera; Kongsawadworakul, Panida; Katsuhara, Maki; Julien, Jean-Louis; Sakr, Soulaiman; Chrestin, Hervé; Narangajavana, Jarunya

    2011-02-15

    Natural rubber is synthesized in laticifers in the inner liber of the rubber tree (Hevea brasiliensis). Upon bark tapping, the latex is expelled due to liber turgor pressure. The mature laticifers are devoid of plasmodesmata; therefore a corresponding decrease in the total latex solid content is likely to occur due to water influx inside the laticifers. Auxins and ethylene used as efficient yield stimulants in mature untapped rubber trees, but, bark treatments with abscisic acid (ABA) and salicylic acid (SA) could also induce a transient increase latex yield. We recently reported that there are three aquaporin genes, HbPIP2;1, HbTIP1;1 and HbPIP1;1, that are regulated differentially after ethylene bark treatment. HbPIP2;1 was up-regulated in both the laticifers and the inner liber tissues, whereas HbTIP1;1 was up-regulated in the latex cells, but very markedly down-regulated in the inner liber tissues. Conversely, HbPIP1;1 was down-regulated in both tissues. In the present study, HbPIP2;1 and HbTIP1;1 showed a similar expression in response to auxin, ABA and SA, as seen in ethylene stimulation, while HbPIP1;1 was slightly regulated by auxin, but neither by ABA nor SA. The analysis of the HbPIP1;1 promoter region indicated the presence of only ethylene and auxin responsive elements. In addition, the poor efficiency of this HbPIP1;1 in increasing plasmalemma water conductance was confirmed in Xenopus oocytes. Thus, an increase in latex yield in response to all of these hormones was proposed to be the major function of aquaporins, HbPIP2;1 and HbTIP1;1. This study emphasized that the circulation of water between the laticifers and their surrounding tissues that result in latex dilution, as well as the probable maintenance of the liber tissues turgor pressure, favor the prolongation of latex flow.

  20. Population Dynamics of the Rubber Plantation Litter Beetle Luprops tristis, in Relation to Annual Cycle of Foliage Phenology of Its Host, the Para Rubber Tree, Hevea brasiliensis

    PubMed Central

    Sabu, Thomas K.; Vinod, K.V.

    2009-01-01

    The population dynamics of the rubber plantation litter beetle, Luprops tristis Fabricius 1801 (Coleoptera: Tenebrionidae) was assessed in relation to the phenology of leaf shedding and defoliation pattern of para rubber trees, Hevea brasiliensis Müll. Arg (Malpighiales: Euphorbiaceae), during a two year study period. The abundance of adults, larvae and pupae per 1m2 of litter sample was recorded. Post dormancy beetles appeared in leaf litter following annual leaf shedding, whereas larvae, pupae and teneral adults were present after leaf flush. No stages were recorded from plantations following the summer rains until the annual litter fall in the next season. Parental adults peaked at the time of leaf sprouting and tender leaf fall. Larvae and teneral adults peaked at the time of premature fall of green leaves and flowers. Teneral adults of six age classes were recorded and all entered dormancy irrespective of the feeding time available to each age class. Females outnumbered males in the parent generation, while the sex ratio of new generation adults was not biased towards either sex. The phenological stages of rubber trees included leaf fall in late December and early January, leaf sprouting and new leaf production in January and flowering in February. All feeding stages of L. tristis peaked in abundance when premature leaves are most abundant in the leaf litter. Prediction of the timing of appearance of various developmental stages of L. tristis in plantations, invasion into buildings and intensity of population build up in rubber belts is possible by tracking the phenology of leaf fall in rubber plantations, time of return of post dormancy adults and the onset of summer rainfall. Perfect synchrony was recorded between the field return of parental adults with annual leaf shedding, the oviposition phase of parental adults with tender leaf fall at the time of leaf sprouting, and larval and teneral adult stages with premature fall of leaves. Premature leaf

  1. Uncovering divergent evolution of α/β-hydrolases: a surprising residue substitution needed to convert Hevea brasiliensis hydroxynitrile lyase into an esterase

    PubMed Central

    Nedrud, David M.; Lin, Hui; Lopez, Gilsinia; Padhi, Santosh K.; Legatt, Graig A.

    2014-01-01

    Hevea brasiliensis hydroxynitrile lyase (HbHNL) and salicylic acid binding protein 2 (SABP2, an esterase) share 45% amino acid sequence identity, the same protein fold, and even the same catalytic triad of Ser-His-Asp. However, they catalyze different reactions: cleavage of hydroxynitriles and hydrolysis of esters, respectively. To understand how other active site differences in the two enzymes enable the same catalytic triad to catalyze different reactions, we substituted amino acid residues in HbHNL with the corresponding residues from SABP2, expecting hydroxynitrile lyase activity to decrease and esterase activity to increase. Previous mechanistic studies and x-ray crystallography suggested that esterase activity requires removal of an active site lysine and threonine from the hydroxynitrile lyase. The Thr11Gly Lys236Gly substitutions in HbHNL reduced hydroxynitrile lyase activity for cleavage of mandelonitrile 100-fold, but increased esterase activity only threefold to kcat ~ 0.1 min−1 for hydrolysis of p-nitrophenyl acetate. Adding a third substitution – Glu79His – increased esterase activity more than tenfold to kcat ~ 1.6 min−1. The specificity constant (kcat/KM) for this triple substitution variant versus wild type HbHNL shifted more than one million-fold from hydroxynitrile lyase activity (acetone cyanohydrin substrate) to esterase activity (p-nitrophenyl acetate substrate). The contribution of Glu79His to esterase activity was surprising since esterases and lipases contain many different amino acids at this position, including glutamate. Saturation mutagenesis at position 79 showed that 13 of 19 possible amino acid substitutions increased esterase activity, suggesting that removal of glutamate, not addition of histidine, increased esterase activity. Molecular modeling indicates that Glu79 disrupts esterase activity in HbHNL when its negatively charged side chain distorts the orientation of the catalytic histidine. Naturally occurring glutamate at

  2. Population dynamics of the rubber plantation litter beetle Luprops tristis, in relation to annual cycle of foliage phenology of its host, the para rubber tree, Hevea brasiliensis.

    PubMed

    Sabu, Thomas K; Vinod, K V

    2009-01-01

    The population dynamics of the rubber plantation litter beetle, Luprops tristis Fabricius 1801 (Coleoptera: Tenebrionidae) was assessed in relation to the phenology of leaf shedding and defoliation pattern of para rubber trees, Hevea brasiliensis Müll. Arg (Malpighiales: Euphorbiaceae), during a two year study period. The abundance of adults, larvae and pupae per 1m(2) of litter sample was recorded. Post dormancy beetles appeared in leaf litter following annual leaf shedding, whereas larvae, pupae and teneral adults were present after leaf flush. No stages were recorded from plantations following the summer rains until the annual litter fall in the next season. Parental adults peaked at the time of leaf sprouting and tender leaf fall. Larvae and teneral adults peaked at the time of premature fall of green leaves and flowers. Teneral adults of six age classes were recorded and all entered dormancy irrespective of the feeding time available to each age class. Females outnumbered males in the parent generation, while the sex ratio of new generation adults was not biased towards either sex. The phenological stages of rubber trees included leaf fall in late December and early January, leaf sprouting and new leaf production in January and flowering in February. All feeding stages of L. tristis peaked in abundance when premature leaves are most abundant in the leaf litter. Prediction of the timing of appearance of various developmental stages of L. tristis in plantations, invasion into buildings and intensity of population build up in rubber belts is possible by tracking the phenology of leaf fall in rubber plantations, time of return of post dormancy adults and the onset of summer rainfall. Perfect synchrony was recorded between the field return of parental adults with annual leaf shedding, the oviposition phase of parental adults with tender leaf fall at the time of leaf sprouting, and larval and teneral adult stages with premature fall of leaves. Premature leaf

  3. Leaf ecophysiology of rubber (Hevea brasiliensis) and its implication to stand-level transpiration in the Asian monsoon in mainland Southeast Asia

    NASA Astrophysics Data System (ADS)

    Miyazawa, Y.; Kobayashi, N.; Mudd, R. G.; Yin, S.; LimKhan, T.; Giambelluca, T. W.; Kumagai, T.

    2012-12-01

    In Indochina Peninsula, rubber (Hevea brasiliensis) plantation is expanding rapidly as the major commercial crop. Rubber, which is a native of Amazon rainforests, are thought to have transpiration characteristics different from other native species in this region, which is characterized by high rainfall occurs in rainy season and severe drought in dry season. Studies suggested high stand transpiration rate (E) in rubber plantations, possibly due to the water use even in dry seasons or to high leaf photosynthetic capacity. Despite recent advances about the leaf-level measurements in leaf gas exchange traits, knowledge has been collected without clear linkage to the seasonal trends in stand-level gas exchange and its seasonal trends. In this study, we monitored the leaf-level photosynthetic capacity (Vcmax25) and a parameter for stomatal control (m, Ball et al. 1987) to show whether changes in atmospheric environments and leaf gas exchange traits explain the high E and its seasonal trends (annual peak in mid rainy season). Results showed that rubber had Vcmax25 and m similar to temperate broadleaved tree species and higher than other species in Indochina Peninsula, indicating that high Vcmax25 would be responsible for the higher E than other forests in Indochina Peninsula. Vcmax25 reached an annual maximum soon after leaf expansion before the beginning of rainy season, keep the level until soon before leaf fall in mid dry season and did not supported the hypothesis that these parameters increased in mid rainy season. The m also showed slight seasonal variations without clear trends. Multilayer model well modeled the diurnal trends in measured E using sap flow measurements, except soon after leaf expansion. Constant leaf gas exchange rates and good reproduction of finer time scale E suggested that increased E in mid rainy season was not due to the increased evaporative demand or changes in leaf gas exchange rates, but to the increased LAI. Poor modeling soon after

  4. Molecular cloning and characterization of a cDNA encoding the Paracoccidioides brasiliensis 135 ribosomal protein.

    PubMed

    Jesuino, Rosália S A; Pereira, Maristela; Felipe, M Sueli S; Azevedo, Maristella O; Soares, Célia M A

    2004-06-01

    A 630 bp cDNA encoding an L35 ribosomal protein of Paracoccidioides brasiliensis, designated as Pbl35, was cloned from a yeast expression library. Pbl35 encodes a polypeptide of 125 amino acids, with a predicted molecular mass of 14.5 kDa and a pI of 11.0. The deduced PbL35 shows significant conservation in respect to other described ribosomal L35 proteins from eukaryotes and prokaryotes. Motifs of ribosomal proteins are present in PbL35, including a bipartite nuclear localization signal (NLS) that could be related to the protein addressing to the nucleolus for the ribosomal assembly. The mRNA for PbL35, about 700 nucleotides in length, is expressed at a high level in P. brasiliensis. The PbL35 and the deduced amino acid sequence constitute the first description of a ribosomal protein in P. brasiliensis. The cDNA was deposited in GenBank under accession number AF416509.

  5. Monofunctional catalase P of Paracoccidioides brasiliensis: identification, characterization, molecular cloning and expression analysis.

    PubMed

    Moreira, Sabrina F I; Bailão, Alexandre M; Barbosa, Mônica S; Jesuino, Rosalia S A; Felipe, M Sueli Soares; Pereira, Maristela; de Almeida Soares, Célia Maria

    2004-01-30

    Within the context of studies on genes from Paracoccidioides brasiliensis (Pb) potentially associated with fungus-host interaction, we isolated a 61 kDa protein, pI 6.2, that was reactive with sera of patients with paracoccidioidomycosis. This protein was identified as a peroxisomal catalase. A complete cDNA encoding this catalase was isolated from a Pb cDNA library and was designated PbcatP. The cDNA contained a 1509 bp ORF containing 502 amino acids, whose molecular mass was 57 kDa, with a pI of 6.5. The translated protein PbCATP revealed canonical motifs of monofunctional typical small subunit catalases and the peroxisome-PTS-1-targeting signal. The deduced and the native PbCATP demonstrated amino acid sequence homology to known monofunctional catalases and was most closely related to catalases from other fungi. The protein and mRNA were diminished in the mycelial saprobic phase compared to the yeast phase of infection. Protein synthesis and mRNA levels increased during the transition from mycelium to yeast. In addition, the catalase protein was induced when cells were exposed to hydrogen peroxide. The identification and characterization of the PbCATP and cloning and characterization of the cDNA are essential steps for investigating the role of catalase as a defence of P. brasiliensis against oxygen-dependent killing mechanisms. These results suggest that this protein exerts an influence in the virulence of P. brasiliensis.

  6. Chitinase from Paracoccidioides brasiliensis: molecular cloning, structural, phylogenetic, expression and activity analysis.

    PubMed

    Bonfim, Sheyla M R C; Cruz, Aline H S; Jesuino, Rosália S A; Ulhoa, Cirano J; Molinari-Madlum, Eugênia E W I; Soares, Célia M A; Pereira, Maristela

    2006-03-01

    A full-length cDNA encoding a chitinase (Pbcts1) was cloned by screening a cDNA library from the yeast cells of Paracoccidioides brasiliensis. The cDNA consists of 1888 bp and encodes an ORF of 1218 bp corresponding to a protein of 45 kDa with 406 amino acid residues. The deduced PbCTS1 is composed of two signature family 18 catalytic domains and seems to belong to fungal/bacterial class. Phylogenetic analysis of PbCTS1 and other chitinases suggests the existence of paralogs of several chitinases to be grouped based on specialized functions, which may reflect the multiple and diverse roles played by fungi chitinases. Glycosyl hydrolase activity assays demonstrated that P. brasiliensis is able to produce and secrete these enzymes mainly during transition from yeast to mycelium. The fungus should be able to use chitin as a carbon source. The presence of an endocytic signal in the deduced protein suggests that it could be secreted by a vesicular nonclassical export pathway. The Pbcts1 expression in mycelium, yeast, during differentiation from mycelium to yeast and in yeast cells obtained from infected mice suggests the relevance of this molecule in P. brasiliensis electing PbCTS1 as an attractive drug target.

  7. How do rubber (Hevea brasiliensis) plantations behave under seasonal water stress in northeastern Thailand and central Cambodia?

    SciTech Connect

    Kumagai, Tomo'omi; Mudd, Ryan G.; Giambelluca, Thomas W.; Kobayashi, Nakako; Miyazawa, Yoshiyuki; Lim, Tiva Khan; Liu, Wen; Huang, Maoyi; Fox, Jefferson M.; Ziegler, Alan D.; Yin, Song; Mak, Sophea Veasna; Kasemsap, Poonpipope

    2015-11-01

    Plantation rubber (Hevea brasiliensis Müll. Arg.) is a viable economic resource for Southeast Asian countries. Consequently, rubber plantations are rapidly expanding into both climatically optimal and sub-optimal environments throughout mainland Southeast Asia, potentially changing the partitioning of water, energy, and carbon at multiple scales, compared with the traditional land covers they are replacing. Delineating the characteristics of biosphere-atmosphere exchange in rubber plantations is therefore important to understanding the impacts of such land use change on environmental processes. We have conducted eddy flux measurements in two rubber plantation sites: (1) Som Sanuk (SS), located northern Thailand; and (2) Cambodian Rubber Research Institute (CRRI), central Cambodia. Both sites have a distinct dry season. Measurements were made over a 3-year period. We used combination of actual evapotranspiration (ET) flux measurements and an inversed version of a simple 2-layer ET model for estimating the mean canopy stomatal conductances (gs), which is among the most effective measures for describing water and energy exchanges and tree water use characteristics. A main novelty in this analysis is that the rubber canopy conductance can be extracted from total surface conductance (including the canopy and the vegetation floor effects) and hence environmental and biological controls on rubber tree gs are explicitly compared at each site in different seasons and years. It is demonstrated how each studied rubber plantation copes with each strong seasonal drought via tree water use strategies. Potential tree water use deficit (precipitation (P) – potential evaporation (ET_POT)) for each season (i.e., December-February: DJF, March-May: MAM, June-August: JJA, and September-November: SON) revealed in which season and how the water use should be controlled. We found that in seasons when actual tree water use deficit (P

  8. Molecular cloning and characterization of a glucan synthase gene from the human pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Pereira, M; Felipe, M S; Brígido, M M; Soares, C M; Azevedo, M O

    2000-03-30

    1,3-beta-D-glucan is a fungal cell wall polymer synthesized by the multi-subunit enzyme 1,3-beta-D-glucan synthase. A subunit of this integral membrane protein was first described as the product of the FKS1 gene from Saccharomyces cerevisiae using echinocandin mutants. Other FKS1 genes were also reported for Candida albicans, Aspergillus nidulans and Cryptococcus neoformans. Here, we report the nucleotide sequence of the first homologous FKS gene cloned from the pathogenic fungus Paracoccidioides brasiliensis. An open reading frame of 5942 bp was identified in the complete sequence, interrupted by two putative introns, the first close to the 5' end and the second close to the 3' end of the gene. A promoter region is also described containing consensus sequences such as canonical TATA and CAAT boxes and, possibly, multiple sites for glucose regulation by creA protein. The deduced sequence of 1926 amino acid show more than 85% similarity to FksAp from A. nidulans, and 71% to Fks1p and Fks2p from S. cerevisiae. Computational analysis of P. brasiliensis Fks1p suggests a similar structure to transmembrane proteins, such as FksAp, with the presence of two domains composed by hydrophobic helices that limit the putative highly hydrophilic catalytic domain within the cytoplasm.

  9. Regulation of HbPIP2;3, a Latex-Abundant Water Transporter, Is Associated with Latex Dilution and Yield in the Rubber Tree (Hevea brasiliensis Muell. Arg.)

    PubMed Central

    Cai, Xiuqing; Wang, Jin; Rookes, James; Lin, Weifu; Cahill, David; Kong, Lingxue

    2015-01-01

    Rubber tree (Hevea brasiliensis) latex, the source of natural rubber, is synthesised in the cytoplasm of laticifers. Efficient water inflow into laticifers is crucial for latex flow and production since it is the determinant of the total solid content of latex and its fluidity after tapping. As the mature laticifer vessel rings are devoid of plasmodesmata, water exchange between laticifers and surrounding cells is believed to be governed by plasma membrane intrinsic proteins (PIPs). To identify the most important PIP aquaporin in the water balance of laticifers, the transcriptional profiles of ten-latex-expressed PIPs were analysed. One of the most abundant transcripts, designated HbPIP2;3, was characterised in this study. When tested in Xenopus laevis oocytes HbPIP2;3 showed a high efficiency in increasing plasmalemma water conductance. Expression analysis indicated that the HbPIP2;3 gene was preferentially expressed in latex, and the transcripts were up-regulated by both wounding and exogenously applied Ethrel (a commonly-used ethylene releaser). Although regular tapping up-regulated the expression of HbPIP2;3 during the first few tappings of the virginal rubber trees, the transcriptional kinetics of HbPIP2;3 to Ethrel stimulation in the regularly tapped tree exhibited a similar pattern to that of the previously reported HbPIP2;1 in the virginal rubber trees. Furthermore, the mRNA level of HbPIP2;3 was associated with clonal yield potential and the Ethrel stimulation response. Together, these results have revealed the central regulatory role of HbPIP2;3 in laticifer water balance and ethylene stimulation of latex production in Hevea. PMID:25927524

  10. Regulation of HbPIP2;3, a Latex-Abundant Water Transporter, Is Associated with Latex Dilution and Yield in the Rubber Tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    An, Feng; Zou, Zhi; Cai, Xiuqing; Wang, Jin; Rookes, James; Lin, Weifu; Cahill, David; Kong, Lingxue

    2015-01-01

    Rubber tree (Hevea brasiliensis) latex, the source of natural rubber, is synthesised in the cytoplasm of laticifers. Efficient water inflow into laticifers is crucial for latex flow and production since it is the determinant of the total solid content of latex and its fluidity after tapping. As the mature laticifer vessel rings are devoid of plasmodesmata, water exchange between laticifers and surrounding cells is believed to be governed by plasma membrane intrinsic proteins (PIPs). To identify the most important PIP aquaporin in the water balance of laticifers, the transcriptional profiles of ten-latex-expressed PIPs were analysed. One of the most abundant transcripts, designated HbPIP2;3, was characterised in this study. When tested in Xenopus laevis oocytes HbPIP2;3 showed a high efficiency in increasing plasmalemma water conductance. Expression analysis indicated that the HbPIP2;3 gene was preferentially expressed in latex, and the transcripts were up-regulated by both wounding and exogenously applied Ethrel (a commonly-used ethylene releaser). Although regular tapping up-regulated the expression of HbPIP2;3 during the first few tappings of the virginal rubber trees, the transcriptional kinetics of HbPIP2;3 to Ethrel stimulation in the regularly tapped tree exhibited a similar pattern to that of the previously reported HbPIP2;1 in the virginal rubber trees. Furthermore, the mRNA level of HbPIP2;3 was associated with clonal yield potential and the Ethrel stimulation response. Together, these results have revealed the central regulatory role of HbPIP2;3 in laticifer water balance and ethylene stimulation of latex production in Hevea.

  11. Cloning and characterization of laccase DNA from the Royal Sun medicinal mushroom, Agaricus brasiliensis (higher Basidiomycetes).

    PubMed

    Matsumoto-Akanuma, Akiko; Akanuma, Satoshi; Motoi, Masuro; Yamagishi, Akihiko; Ohno, Naohito

    2014-01-01

    Laccase isozymes have been identified in several fungi. We report the cloning of 4 laccase genes from the medicinal mushroom Agaricus brasiliensis. The lac1 gene contained a 1560-base pair (bp) open reading frame (ORF) encoding 520 amino acids that was interrupted with 14 introns in genomic DNA. The deduced amino acid sequence indicated a multicopper oxidase signature 1 and 2 multicopper oxidase signature 2. The lac2 gene contained a 1566-bp ORF encoding 522 amino acids that was interrupted with 13 introns in genomic DNA. A number of different nucleotides were observed in whole regions containing the substitution of amino acid residues (lac2a and lac2b). The partial DNA fragments of lac3 and lac4 genes were subcloned using the semi-random two-step polymerase chain reaction method. The lac3 and lac4 genes contained coding sequences with a 1575-bp ORF encoding 525 amino acids and a 1584-bp ORF encoding 528 amino acids, respectively. However, the whole complementary DNA fragment of both laccases could not be amplified with polymerase chain reaction against the complementary DNA library; therefore, introns were deduced based on the GT-AG rule and multiple alignment of laccases from other fungi, which showed high identity. All laccases from A. brasiliensis conserved the fungal laccase signature sequence and suggest 2 subfamilies according to the location of introns and phylogenetic analysis. The genes lac2 and lac4 had a high degree of identity, and the lac2a gene was located upstream of the lac4 gene.

  12. De novo assembly and characterization of bark transcriptome using Illumina sequencing and development of EST-SSR markers in rubber tree (Hevea brasiliensis Muell. Arg.)

    PubMed Central

    2012-01-01

    Background In rubber tree, bark is one of important agricultural and biological organs. However, the molecular mechanism involved in the bark formation and development in rubber tree remains largely unknown, which is at least partially due to lack of bark transcriptomic and genomic information. Therefore, it is necessary to carried out high-throughput transcriptome sequencing of rubber tree bark to generate enormous transcript sequences for the functional characterization and molecular marker development. Results In this study, more than 30 million sequencing reads were generated using Illumina paired-end sequencing technology. In total, 22,756 unigenes with an average length of 485 bp were obtained with de novo assembly. The similarity search indicated that 16,520 and 12,558 unigenes showed significant similarities to known proteins from NCBI non-redundant and Swissprot protein databases, respectively. Among these annotated unigenes, 6,867 and 5,559 unigenes were separately assigned to Gene Ontology (GO) and Clusters of Orthologous Group (COG). When 22,756 unigenes searched against the Kyoto Encyclopedia of Genes and Genomes Pathway (KEGG) database, 12,097 unigenes were assigned to 5 main categories including 123 KEGG pathways. Among the main KEGG categories, metabolism was the biggest category (9,043, 74.75%), suggesting the active metabolic processes in rubber tree bark. In addition, a total of 39,257 EST-SSRs were identified from 22,756 unigenes, and the characterizations of EST-SSRs were further analyzed in rubber tree. 110 potential marker sites were randomly selected to validate the assembly quality and develop EST-SSR markers. Among 13 Hevea germplasms, PCR success rate and polymorphism rate of 110 markers were separately 96.36% and 55.45% in this study. Conclusion By assembling and analyzing de novo transcriptome sequencing data, we reported the comprehensive functional characterization of rubber tree bark. This research generated a substantial fraction

  13. Seasonal Patterns of Fine Root Production and Turnover in a Mature Rubber Tree (Hevea brasiliensis Müll. Arg.) Stand- Differentiation with Soil Depth and Implications for Soil Carbon Stocks

    PubMed Central

    Maeght, Jean-Luc; Gonkhamdee, Santimaitree; Clément, Corentin; Isarangkool Na Ayutthaya, Supat; Stokes, Alexia; Pierret, Alain

    2015-01-01

    Fine root dynamics is a main driver of soil carbon stocks, particularly in tropical forests, yet major uncertainties still surround estimates of fine root production and turnover. This lack of knowledge is largely due to the fact that studying root dynamics in situ, particularly deep in the soil, remains highly challenging. We explored the interactions between fine root dynamics, soil depth, and rainfall in mature rubber trees (Hevea brasiliensis Müll. Arg.) exposed to sub-optimal edaphic and climatic conditions. A root observation access well was installed in northern Thailand to monitor root dynamics along a 4.5 m deep soil profile. Image-based measurements of root elongation and lifespan of individual roots were carried out at monthly intervals over 3 years. Soil depth was found to have a significant effect on root turnover. Surprisingly, root turnover increased with soil depth and root half-life was 16, 6–8, and only 4 months at 0.5, 1.0, 2.5, and 3.0 m deep, respectively (with the exception of roots at 4.5 m which had a half-life similar to that found between depths of 1.0 and 2.5 m). Within the first two meters of the soil profile, the highest rates of root emergence occurred about 3 months after the onset of the rainy season, while deeper in the soil, root emergence was not linked to the rainfall pattern. Root emergence was limited during leaf flushing (between March and May), particularly within the first two meters of the profile. Between soil depths of 0.5 and 2.0 m, root mortality appeared independent of variations in root emergence, but below 2.0 m, peaks in root emergence and death were synchronized. Shallow parts of the root system were more responsive to rainfall than their deeper counterparts. Increased root emergence in deep soil toward the onset of the dry season could correspond to a drought acclimation mechanism, with the relative importance of deep water capture increasing once rainfall ceased. The considerable soil depth regularly explored

  14. Molecular cloning, characterization and expression of the heat shock protein 60 gene from the human pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Izacc, S M; Gomez, F J; Jesuino, R S; Fonseca, C A; Felipe, M S; Deepe, G S; Soares, C M

    2001-10-01

    A gene encoding the heat shock protein (HSP) 60 from Paracoccidioides brasiliensis (Pb) was cloned and characterized. The hsp60 gene is composed of three exons divided by two introns. Structural analysis of the promoter detected canonical sequences characteristic of regulatory regions from eukaryotic genes. The deduced amino acid sequence of the Pb hsp60 gene and the respective cloned cDNA consists of 592 residues highly homologous to other fungal HSP60 proteins. The hsp60 gene is present as a single copy in the genome, as shown by Southern blot analysis. The HSP60 protein was isolated from Pb yeast cellular extracts. N-terminal amino acid sequencing of HSP60 confirmed that the cloned hsp60 gene correlated to the predicted protein in Pb. HSP60 expression appeared to be regulated during form transition in Pb, as different levels of expression were detected in in vitro labeling of cells and northern blot analysis. The complete coding region of Pb hsp60 was fused with plasmid pGEX-4T-3 and expressed in Escherichia coli as a glutathione S-transferase-tagged recombinant protein. The protein reacted with a mouse monoclonal antibody raised to a human recombinant HSP60. Western immunoblot experiments demonstrated that the recombinant protein and the native HSP60 were recognized by sera from humans with paracoccidioidomycosis (PCM).

  15. Molecular and biochemical characterization of a cyanogenic β-glucosidase in the inner bark tissues of rubber tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Tian, Wei-Min; Zhang, Hua; Yang, Shu-Guang; Shi, Min-Jing; Wang, Xu-Chu; Dai, Long-Jun; Chen, Yue-Yi

    2013-05-15

    Tapping causes the loss of large amounts of latex from laticifers and subsequently enhances latex regeneration, a high carbon- and nitrogen-cost activity in rubber tree. It is suggested that a 67 kDa protein associated with protein-storing cells in the inner bark tissues of rubber tree plays an important role in meeting the nitrogen demand for latex regeneration. Here, the 67 kDa protein was further characterized by a combination of cell biological, molecular biological and biochemical techniques. Immunogold labeling showed that the 67 kDa protein was specifically localized in the central vacuole of protein-storing cells. A full-length cDNA, referred to as HbVSP1, was cloned. The HbVSP1 contained a 1584 bp open reading frame encoding a protein of 527 amino acids. The putative protein HbVSP1 shared high identity with the P66 protein from rubber tree and proteins of the linamarase, and bg1A from cassava (Manihot esculenta). HbVSP1 contained the active site sequences of β-glucosidase, TFNEP and I/VTENG. In vitro analysis showed that the 67 kDa protein exhibited the activity of both β-glucosidase and linamarase and was thus characterized as a cyanogenic β-glucosidase. Proteins immuno-related to the 67 kDa protein were present in leaves and lutoids of laticifers. Tapping down-regulated the expression of HbVSP1, but up-regulated the expression of genes encoding the key enzymes for rubber biosynthesis, while the effect of resting from tapping was the reverse. Taken together, the results suggest that the 67 kDa protein is a vacuole-localized cyanogenic β-glucosidase encoded by HbVSP1 and may have a role in nitrogen storage in inner bark tissues of trunk during the leafless periods when rubber tree is rested from tapping.

  16. Effect of non-rubber constituents on Guayule and Hevea rubber intrinsic properties

    USDA-ARS?s Scientific Manuscript database

    To meet the increasing demand for natural rubber (NR), currently sourced from the tropical rubber tree Hevea brasiliensis, and address price volatility and steadily increasing labor costs, alternate rubber-producing species are in commercial development. One of these, guayule (Parthenium argentatum)...

  17. Cloning and functional analysis of the orotidine-5'-phosphate decarboxylase gene (PbrURA3) of the pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Reinoso, Cristina; Sorais, Françoise; Niño-Vega, Gustavo A; Fermiñán, Encarnación; San-Blas, Gioconda; Domínguez, Angel

    2005-07-15

    A genomic clone encoding the Paracoccidioides brasiliensis orotidine monophosphate decarboxylase gene (PbrURA3) was isolated by screening a subgenomic plasmid DNA library of this fungus, using a PCR amplification product of the gene as a probe. Sequence analysis revealed that the gene contains an open reading frame of 855 bp with a single intron (162 bp), and encodes a putative 285 amino acids polypeptide of estimated molecular weight 31.1 kDa and isoelectric point 6.5. The deduced amino acid sequence predicted a 73.4% identity with orotidine monophosphate decarboxylase of Aspergillus nidulans. Functionality of the gene was demonstrated by transformation into a Saccharomyces cerevisiae ura3 null mutant.

  18. Molecular cloning and characterization of a cDNA encoding the N-acetyl-beta-D-glucosaminidase homologue of Paracoccidioides brasiliensis.

    PubMed

    Santos, Mônica O; Pereira, Maristela; Felipe, Maria Sueli S; Jesuino, Rosalia Santos A; Ulhoa, Cirano J; Soares, Renata de Bastos A; Soares, Celia Maria de A

    2004-06-01

    A cDNA encoding the N-acetyl-beta-D-glucosaminidase (NAG) protein of Paracoccidioides brasiliensis, Pb NAG1, was cloned and characterized. The 2663-nucleotide sequence of the cDNA consisted of a single open reading frame encoding a protein with a predicted molecular mass of 64.73 kDa and an isoeletric point of 6.35. The predicted protein includes a putative 30-amino-acid signal peptide. The protein as a whole shares considerable sequence similarity with 'classic' NAG. The primary sequence of Pb NAG1 was used to infer phylogenetic relationships. The amino acid sequence of Pb NAG1 has 45, 31 and 30% identity, respectively, with homologous sequences from Trichoderma harzianum, Aspergillus nidulans and Candida albicans. In particular, striking homology was observed with the active site regions of the glycosyl hydrolase group of proteins (family 20). The expected active site consensus motif G X D E and catalytic Asp and Glu residues at positions 373 and 374 were found, reinforcing that Pb NAG1 belongs to glycosyl hydrolase family 20. The nucleotide sequence of Pb nag1 and its flanking regions have been deposited, along with the amino acid sequence of the deduced protein, in GenBank under accession number AF419158.

  19. Appetite regulating factors in dourado, Salminus brasiliensis: cDNA cloning and effects of fasting and feeding on gene expression.

    PubMed

    Volkoff, Hélène; Sabioni, Rafael Estevan; Cyrino, José Eurico Possebon

    2016-10-01

    The dourado, Salminus brasiliensis (Cuvier, 1816) is a freshwater piscivorous Characin native to South American rivers. Owing to the high quality of its flesh and its fast growth, it is the object of both capture fisheries and fish farming. However, very little is known about the endocrine regulation of feeding and metabolism of dourado. In this study, cDNAs for orexin, CART and CCK were isolated in dourado, and their mRNA tissue distributions examined. In order to assess the role of these peptides in the regulation of feeding of dourado, the effects of fasting and feeding on mRNA expression levels of orexin, CART and CCK in the brain as well as CCK in the intestine were assessed. Whereas orexin and CCK have widespread mRNA distributions in the brain and peripheral organs, CART seems to be mostly limited to the brain. Orexin brain expression increased with fasting and displayed periprandial changes, suggesting it is involved in both long- and short-term regulation of feeding and appetite. CART and CCK hypothalamic expressions were not affected by fasting, but displayed periprandial changes with post-feeding decreases, suggesting roles in short-term satiation. CCK expression in the anterior intestine was not affected by fasting and did not display periprandial changes. Overall, our results suggest that orexin, CART and CCK are involved in the physiology of feeding of dourado. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Evaluation of Reference Genes for Quantitative Real-Time PCR Analysis of the Gene Expression in Laticifers on the Basis of Latex Flow in Rubber Tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Chao, Jinquan; Yang, Shuguang; Chen, Yueyi; Tian, Wei-Min

    2016-01-01

    Latex exploitation-caused latex flow is effective in enhancing latex regeneration in laticifer cells of rubber tree. It should be suitable for screening appropriate reference gene for analysis of the expression of latex regeneration-related genes by quantitative real-time PCR (qRT-PCR). In the present study, the expression stability of 23 candidate reference genes was evaluated on the basis of latex flow by using geNorm and NormFinder algorithms. Ubiquitin-protein ligase 2a (UBC2a) and ubiquitin-protein ligase 2b (UBC2b) were the two most stable genes among the selected candidate references in rubber tree clones with differential duration of latex flow. The two genes were also high-ranked in previous reference gene screening across different tissues and experimental conditions. By contrast, the transcripts of latex regeneration-related genes fluctuated significantly during latex flow. The results suggest that screening reference gene during latex flow should be an efficient and effective clue for selection of reference genes in qRT-PCR.

  1. Evaluation of Reference Genes for Quantitative Real-Time PCR Analysis of the Gene Expression in Laticifers on the Basis of Latex Flow in Rubber Tree (Hevea brasiliensis Muell. Arg.)

    PubMed Central

    Chao, Jinquan; Yang, Shuguang; Chen, Yueyi; Tian, Wei-Min

    2016-01-01

    Latex exploitation-caused latex flow is effective in enhancing latex regeneration in laticifer cells of rubber tree. It should be suitable for screening appropriate reference gene for analysis of the expression of latex regeneration-related genes by quantitative real-time PCR (qRT-PCR). In the present study, the expression stability of 23 candidate reference genes was evaluated on the basis of latex flow by using geNorm and NormFinder algorithms. Ubiquitin-protein ligase 2a (UBC2a) and ubiquitin-protein ligase 2b (UBC2b) were the two most stable genes among the selected candidate references in rubber tree clones with differential duration of latex flow. The two genes were also high-ranked in previous reference gene screening across different tissues and experimental conditions. By contrast, the transcripts of latex regeneration-related genes fluctuated significantly during latex flow. The results suggest that screening reference gene during latex flow should be an efficient and effective clue for selection of reference genes in qRT-PCR. PMID:27524995

  2. Polyphenol oxidases from latex of Hevea brasiliensis: purification and characterization.

    PubMed

    Wititsuwannakul, Dhirayos; Chareonthiphakorn, Nopphakaew; Pace, Mario; Wititsuwannakul, Rapepun

    2002-09-01

    Polyphenol oxidase (PPO) was isolated from the B-serum obtained after repetitive freeze-thawing of the bottom fraction isolated from ultracentrifuged fresh latex. The B-serum was subjected to acetone precipitation and CM-Sepharose chromatography, affording two PPOs, PPO-I and PPO-II, which, upon SDS-PAGE, were 32 and 34 kDa, respectively. Both PPOs possessed the same pI (9.2), optimum pH (7) and optimum temperature (35-45 degrees C). They are stable up to 60 degrees C and active at broad pH ranges from 4-9. The K(m) values of PPO-I for dopamine, L-dopa and catechol as substrates are 2.08, 8.33 and 9.09 mM, while those for PPO-II are 2.12, 4.76 and 7.14 mM, respectively. Among various PPO inhibitors tested, 4-hexylresorcinol was the most potent. Anionic detergents were among the most effective activators of the enzymes, while cationic and nonionic detergents showed little and no effect on the PPO activities, respectively.

  3. Cloning

    MedlinePlus

    Cloning describes the processes used to create an exact genetic replica of another cell, tissue or organism. ... named Dolly. There are three different types of cloning: Gene cloning, which creates copies of genes or ...

  4. De novo hybrid assembly of the rubber tree genome reveals evidence of paleotetraploidy in Hevea species

    PubMed Central

    Pootakham, Wirulda; Sonthirod, Chutima; Naktang, Chaiwat; Ruang-Areerate, Panthita; Yoocha, Thippawan; Sangsrakru, Duangjai; Theerawattanasuk, Kanikar; Rattanawong, Ratchanee; Lekawipat, Napawan; Tangphatsornruang, Sithichoke

    2017-01-01

    Para rubber tree (Hevea brasiliensis) is an important economic species as it is the sole commercial producer of high-quality natural rubber. Here, we report a de novo hybrid assembly of BPM24 accession, which exhibits resistance to major fungal pathogens in Southeast Asia. Deep-coverage 454/Illumina short-read and Pacific Biosciences (PacBio) long-read sequence data were acquired to generate a preliminary draft, which was subsequently scaffolded using a long-range “Chicago” technique to obtain a final assembly of 1.26 Gb (N50 = 96.8 kb). The assembled genome contains 69.2% repetitive sequences and has a GC content of 34.31%. Using a high-density SNP-based genetic map, we were able to anchor 28.9% of the genome assembly (363 Mb) associated with over two thirds of the predicted protein-coding genes into rubber tree’s 18 linkage groups. These genetically anchored sequences allowed comparative analyses of the intragenomic homeologous synteny, providing the first concrete evidence to demonstrate the presence of paleotetraploidy in Hevea species. Additionally, the degree of macrosynteny conservation observed between rubber tree and cassava strongly supports the hypothesis that the paleotetraploidization event took place prior to the divergence of the Hevea and Manihot species. PMID:28150702

  5. Cloning

    MedlinePlus

    ... 2001, researchers produced the first clone of an endangered species: a type of Asian ox known as a ... few days after its birth. In 2003, another endangered type of ox, called the ... many species that would otherwise disappear, others argue that cloning ...

  6. In vitro synthesis of high molecular weight rubber by Hevea small rubber particles.

    PubMed

    Rojruthai, Porntip; Sakdapipanich, Jitladda Tangpakdee; Takahashi, Seiji; Hyegin, Lee; Noike, Motoyoshi; Koyama, Tanetoshi; Tanaka, Yasuyuki

    2010-02-01

    Hevea brasiliensis is one of few higher plants producing the commercial natural rubber used in many significant applications. The biosynthesis of high molecular weight rubber molecules by the higher plants has not been clarified yet. Here, the in vitro rubber biosynthesis was performed by using enzymatically active small rubber particles (SRP) from Hevea. The mechanism of the in vitro rubber synthesis was investigated by the molecular weight distribution (MWD). The highly purified SRP prepared by gel filtration and centrifugation in the presence of Triton((R)) X-100 showed the low isopentenyl diphosphate (IPP) incorporation for the chain extension mechanism of pre-existing rubber. The MWD of in vitro rubber elongated from the pre-existing rubber chains in SRP was analyzed for the first time in the case of H. brasiliensis by incubating without the addition of any initiator. The rubber transferase activity of 70% incorporation of the added IPP (w/w) was obtained when farnesyl diphosphate was present as the allylic diphosphate initiator. The in vitro synthesized rubber showed a typical bimodal MWD of high and low molecular weight fractions in GPC analysis, which was similar to that of the in vivo rubber with peaks at around 10(6) and 10(5) Da or lower. The reaction time independence and dependence of molecular weight of high and low molecular weight fractions, respectively, indicated that the high molecular weight rubber was synthesized from the chain extension of pre-existing rubber molecules whereas the lower one was from the chain elongation of rubber molecules newly synthesized from the added allylic substrates.

  7. Cloning and functional characterization of β-1, 3-glucanase gene from Podophyllum hexandrum - a high altitude Himalayan plant.

    PubMed

    Dogra, Vivek; Sreenivasulu, Yelam

    2015-01-01

    Podophyllum hexandrum is a high-altitude medicinal plant exploited for its etoposides which are potential anticancer compounds. ß-1, 3-glucanase cDNA was cloned from the germinating seeds of Podophyllum (Ph-glucanase). Glucanases belong to pathogenesis related glycohydralase family of proteins, which also play an important role in endosperm weakening and testa rupture during seed germination. Analysis of cloned nucleotide sequence revealed Ph-glucanase with an open reading frame of 852bp encoding a protein of 283 amino acids with a molecular mass of 31kDa and pI of 4.39. In-silico structure prediction of Ph-glucanase showed homology with that of Hevea brasiliensis (3em5B). Structural stability and enhanced catalytic efficiency in harsh climatic conditions possibly due to the presence of glycosyl hydrolase motif (LGIVISESGWPSAG) and a connecting loop towards inner side and well exposed carbohydrate metabolism domain-COG5309, can readily hydrolyse cell wall sugar moieties. Seeds from the transgenic Arabidopsis plants over-expressing Ph-glucanase showed better germination performance against a wide range of temperatures and abscisic acid (ABA) stress. This can be attributed to the accumulation of Ph-glucanase at both transcript and protein levels during the seed germination in transgenic Arabidopsis. Results confirm that the cloned novel seed specific glucanase from a cold desert plant Podophyllum could be used for the manipulation of different plant species seeds against various harsh conditions.

  8. Comparative transcriptome analysis of latex from rubber tree clone CATAS8-79 and PR107 reveals new cues for the regulation of latex regeneration and duration of latex flow.

    PubMed

    Chao, Jinquan; Chen, Yueyi; Wu, Shaohua; Tian, Wei-Min

    2015-04-18

    Rubber tree (Hevea brasiliensis Muell. Arg.) is the primarily commercial source of natural rubber in the world. Latex regeneration and duration of latex flow after tapping are the two factors that determine rubber yield of rubber tree, and exhibit a huge variation between rubber tree clones CATAS8-79 and PR107. To dissect the molecular mechanism for the regulation of latex regeneration and duration of latex flow, we sequenced and comparatively analyzed latex of rubber tree clone CATAS8-79 and PR107 at transriptome level. More than 26 million clean reads were generated in each pool and 51,829 all-unigenes were totally assembled. A total of 6,726 unigenes with differential expression patterns were detected between CATAS8-79 and PR107. Functional analysis showed that genes related to mass of categories were differentially enriched between the two clones. Expression pattern of genes which were involved in latex regeneration and duration of latex flow upon successive tapping was analyzed by quantitative PCR. Several genes related to rubber biosynthesis, cellulose and lignin biosynthesis and rubber particle aggregation were differentially expressed between CATAS8-79 and PR107. This is the first report about probing latex regeneration and duration of latex flow by comparative transcriptome analysis. Among all the suggested factors, it is more important that the level of endogenous jasmonates, carbohydrate metabolism, hydroxymethylglutaryl-CoA reductase (HMGR) and Hevea rubber transferase (HRT) in mevalonate (MVA) parthway for latex regeneration while the level of endogenous ethylene (ETH), lignin content of laticifer cell wall, antioxidants and glucanases for the duration of latex flow. These data will provide new cues for understanding the molecular mechanism for the regulation of latex regeneration and duration of latex flow in rubber tree.

  9. Genome-wide identification and characterization of WRKY gene family in Hevea brasiliensis.

    PubMed

    Li, Hui-Liang; Guo, Dong; Yang, Zi-Ping; Tang, Xiao; Peng, Shi-Qing

    2014-07-01

    WRKY proteins constitute a large family of transcription factors. In this study, we identified 81 WRKY genes (named HbWRKY1 to HbWRKY81) in the latest rubber tree genome. Tissue-specific expression profiles showed that 74 HbWRKYs were expressed in at least one of the tissues and the other 7 genes showed very low expression in all tissues tested, which suggested that HbWRKYs took part in many cellular processes. The responses of 20 selected HbWRKYs to jasmonic acid (JA) and ethylene (ET) were analyzed in the latex. 17 HbWRKYs responded to at least one treatment, which included 15 HbWRKYs responding to JA treatment, 15 HbWRKYs to ET, which suggested that these HbWRKYs were regulated by JA and ET. We also observed that HbWRKY3, 14, and 55 bind HbSRPP promoter and activate the transcription in yeast. This study suggests that HbWRKY proteins maybe involved in the transcriptional regulation of nature rubber biosynthesis. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Microdistribution of chromated copper arsenate preservative in rubberwood (Hevea brasiliensis Muell. Arg.)

    NASA Astrophysics Data System (ADS)

    Jusoh, Ismail Bin

    2000-08-01

    Rubberwood is popular for making indoor furniture since rubberwood is relatively abundant and sustainable. Currently more than 60% of the total annual rubberwood produced by rubber plantation is used as fuelwood. Rubberwood has the potential for both indoor and outdoor application. For exterior applications, preservative treatment is needed to extend the service life of rubberwood. The objectives of this study are to (1) assess treatability of rubberwood with chromated copper arsenate (CCA) preservative, (2) evaluate the natural decay resistance and efficacy of CCA on rubberwood, and (3) study the microdistribution of CCA components in rubberwood cells. The treatability of rubberwood was determined by measuring the penetration and retention of CCA type C preservative after a full-cell treatment. Natural decay resistance and efficacy of CCA treatment on rubberwood was estimated using a laboratory soilblock test according to AWPA E 10-91. The microdistribution of chromium, copper and arsenic in CCA-treated rubberwood was studied using scanning electron microscope in conjunction with energy dispersive X-ray analyzer (SEM-EDXA). As expected, longitudinal permeability was found to be better than the radial and the tangential permeability. The penetration and retention in the radial direction was about 3 times better than in the tangential direction. Longer pressure period increased penetration and retention of CCA type C in rubberwood. Complete penetration was achieved after 4 hours of pressure (1240 kPa) treatment. A pre-treatment steaming improved the treatability of rubberwood regardless of the anatomical direction. The average weight loss by white rot and brown rot was about 1.5 times higher than that of soft rot. A linear relationship was found between the weight loss and the incubation period for all the six test fungi. A CCA retention of 4.1 kg/m3 reduced weight loss to about 10% and retention of 14.5 kg/m3 reduced the weight loss of all test fungi at less than 2%. Vessels contained high level of chromium, copper, and arsenic compared to fibers. Chromium level was the highest, followed by arsenic and then copper in rubberwood cells. After the full cell treatment, fibers contained about 0.42%, 0.63%, and 1.02% of copper after treatment with 4.1 kg/m3, 10.5 kg/m 3, and 14.5 kg/m3 of CCA, respectively. Highest levels of Cr, Cu, and As were recorded in fiber-to-vessel cell corner (FVCC ) and Fiber-to-vessel middle lamella (FVML) and the lowest was recorded in S2 layer of fiber. Linescan analyses showed that higher count rates of carbon, oxygen, chromium, copper, and arsenic were found in the middle lamella compared to the fiber S2 layer in CCA-treated rubberwood. The increase of the solution strength in chromium, copper, and arsenic corresponds to an increase in Cr, Cu, and As level in wood cells.

  11. Variation of Soil Bacterial Communities in a Chronosequence of Rubber Tree (Hevea brasiliensis) Plantations

    PubMed Central

    Zhou, Yu-Jie; Li, Jian-Hua; Ross Friedman, Cynthia; Wang, Hua-Feng

    2017-01-01

    Regarding rubber tree plantations, researchers lack a basic understanding of soil microbial communities; specifically, little is known about whether or not soil microbial variation is correlated with succession in these plantations. In this paper, we used high-throughput sequencing of the 16S rRNA gene to investigate the diversity and composition of the soil bacterial communities in a chronosequence of rubber tree plantations that were 5, 10, 13, 18, 25, and 30 years old. We determined that: (1) Soil bacterial diversity and composition show changes over the succession stages of rubber tree plantations. The diversity of soil bacteria were highest in 10, 13, and 18 year-old rubber tree plantations, followed by 30 year-old rubber tree plantations, whereas 5 and 25 year-old rubber tree plantations had the lowest values for diversity. A total of 438,870 16S rDNA sequences were detected in 18 soil samples from six rubber tree plantations, found in 28 phyla, 66 classes, 139 orders, 245 families, 355 genera, and 645 species, with 1.01% sequences from unclassified bacteria. The dominant phyla were Acidobacteria, Proteobacteria, Chloroflexi, Actinobacteria, and Verrucomicrobia (relative abundance large than 3%). There were differences in soil bacterial communities among different succession stages of rubber tree plantation. (2) Soil bacteria diversity and composition in the different stages was closely related to pH, vegetation, soil nutrient, and altitude, of which pH, and vegetation were the main drivers. PMID:28611794

  12. Transcriptome analyses reveal molecular mechanism underlying tapping panel dryness of rubber tree (Hevea brasiliensis).

    PubMed

    Li, Dejun; Wang, Xuncheng; Deng, Zhi; Liu, Hui; Yang, Hong; He, Guangming

    2016-03-23

    Tapping panel dryness (TPD) is a serious threat to natural rubber yields from rubber trees, but the molecular mechanisms underlying TPD remain poorly understood. To identify TPD-related genes and reveal these molecular mechanisms, we sequenced and compared the transcriptomes of bark between healthy and TPD trees. In total, 57,760 assembled genes were obtained and analyzed in details. In contrast to healthy rubber trees, 5652 and 2485 genes were up- or downregulated, respectively, in TPD trees. The TPD-related genes were significantly enriched in eight GO terms and five KEGG pathways and were closely associated with ROS metabolism, programmed cell death and rubber biosynthesis. Our results suggest that rubber tree TPD is a complex process involving many genes. The observed lower rubber yield from TPD trees might result from lower isopentenyl diphosphate (IPP) available for rubber biosynthesis and from downregulation of the genes in post-IPP steps of rubber biosynthesis pathway. Our results not only extend our understanding of the complex molecular events involved in TPD but also will be useful for developing effective measures to control TPD of rubber trees.

  13. A simple framework to analyze water constraints on seasonal transpiration in rubber tree (Hevea brasiliensis) plantations

    PubMed Central

    Sopharat, Jessada; Gay, Frederic; Thaler, Philippe; Sdoodee, Sayan; Isarangkool Na Ayutthaya, Supat; Tanavud, Charlchai; Hammecker, Claude; Do, Frederic C.

    2015-01-01

    Climate change and fast extension in climatically suboptimal areas threaten the sustainability of rubber tree cultivation. A simple framework based on reduction factors of potential transpiration was tested to evaluate the water constraints on seasonal transpiration in tropical sub-humid climates, according pedoclimatic conditions. We selected a representative, mature stand in a drought-prone area. Tree transpiration, evaporative demand and soil water availability were measured every day over 15 months. The results showed that basic relationships with evaporative demand, leaf area index and soil water availability were globally supported. However, the implementation of a regulation of transpiration at high evaporative demand whatever soil water availability was necessary to avoid large overestimates of transpiration. The details of regulation were confirmed by the analysis of canopy conductance response to vapor pressure deficit. The final objective of providing hierarchy between the main regulation factors of seasonal and annual transpiration was achieved. In the tested environmental conditions, the impact of atmospheric drought appeared larger importance than soil drought contrary to expectations. Our results support the interest in simple models to provide a first diagnosis of water constraints on transpiration with limited data, and to help decision making toward more sustainable rubber plantations. PMID:25610443

  14. A simple framework to analyze water constraints on seasonal transpiration in rubber tree (Hevea brasiliensis) plantations.

    PubMed

    Sopharat, Jessada; Gay, Frederic; Thaler, Philippe; Sdoodee, Sayan; Isarangkool Na Ayutthaya, Supat; Tanavud, Charlchai; Hammecker, Claude; Do, Frederic C

    2014-01-01

    Climate change and fast extension in climatically suboptimal areas threaten the sustainability of rubber tree cultivation. A simple framework based on reduction factors of potential transpiration was tested to evaluate the water constraints on seasonal transpiration in tropical sub-humid climates, according pedoclimatic conditions. We selected a representative, mature stand in a drought-prone area. Tree transpiration, evaporative demand and soil water availability were measured every day over 15 months. The results showed that basic relationships with evaporative demand, leaf area index and soil water availability were globally supported. However, the implementation of a regulation of transpiration at high evaporative demand whatever soil water availability was necessary to avoid large overestimates of transpiration. The details of regulation were confirmed by the analysis of canopy conductance response to vapor pressure deficit. The final objective of providing hierarchy between the main regulation factors of seasonal and annual transpiration was achieved. In the tested environmental conditions, the impact of atmospheric drought appeared larger importance than soil drought contrary to expectations. Our results support the interest in simple models to provide a first diagnosis of water constraints on transpiration with limited data, and to help decision making toward more sustainable rubber plantations.

  15. Soil carbon stocks decrease following conversion of secondary forests to rubber (Hevea brasiliensis) plantations.

    PubMed

    de Blécourt, Marleen; Brumme, Rainer; Xu, Jianchu; Corre, Marife D; Veldkamp, Edzo

    2013-01-01

    Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha(-1) in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha(-1) to an increase of 8 Mg C ha(-1). In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes.

  16. Soil Carbon Stocks Decrease following Conversion of Secondary Forests to Rubber (Hevea brasiliensis) Plantations

    PubMed Central

    de Blécourt, Marleen; Brumme, Rainer; Xu, Jianchu; Corre, Marife D.; Veldkamp, Edzo

    2013-01-01

    Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha−1 in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha−1 to an increase of 8 Mg C ha−1. In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes. PMID:23894456

  17. The allergenic properties of fresh and preserved Hevea brasiliensis latex protein preparations

    PubMed Central

    KEKWICK, R; BHAMBRI, S; CHABANE, M H; AUTEGARDEN, J-E; LEVY, D A; LEYNADIER, F

    1996-01-01

    The allergenic properties of the proteins of two lyophilized fractions of fresh natural rubber latex obtained by ultracentrifugation, the C serum and the sedimented bottom or lutoid fraction, have been compared with those of the serum proteins of two samples of high ammonia latex (HAL), [A]HALS obtained from HAL stored for more than 1 year, and [M]HALS derived from HAL stored for 6 weeks before ultracentrifugation and lyophilization. The most potent source of allergenic polypeptides both for skin prick testing of latex-sensitive patients and for immunoblots of their blood serum was the lutoid fraction of fresh latex. Skin prick tests and immunoblots of patients' sera showed that the allergenicity of the ammoniated latex decreased during storage. Skin prick tests using fractions of [A]HALS, C serum and lutoid proteins obtained after passage through a Sephacryl S300 column showed that the components of all three preparations which eluted in the largest volumes were almost equally effective in provoking the largest number of responses. Immunoblots of the sera of 43 latex-sensitive individuals showed that the majority (66%) of sera of the adult allergic patients reacted with a polypeptide of 19 kD. No characteristic pattern of binding latex polypeptides could be recognized in the sera from patients who were also asthmatic or from those who had had an anaphylactic response to latex proteins. PMID:8625530

  18. Enhanced solvent extraction of polar lipids associated with rubber particles from Hevea brasiliensis.

    PubMed

    Bonfils, Frederic; Ehabe, Eugene Ejolle; Aymard, Christian; Vaysse, Laurent; Sainte-Beuve, Jerome

    2007-01-01

    Biochemical studies of lipids bound to rubber particles have been complicated due to the solubility of polyisoprene chains in most extracting solvents and the rather delicate nature of polar lipids that are often denatured when traditional solvent extraction techniques are employed. In this paper, we describe a traditional technique and accompanying solvents that permit optimal extraction of rubber particle bound lipids. The technique, which is validated after characterizing the lipid extracts by elemental analysis, silica column adsorption and thin layer chromatography, appeared more suitable for extracting total lipids with optimal glycolipid and phospholipid contents. This technique is proposed as an alternative to traditional extraction methods used for solid natural rubber as it offers advantages with respect to ease of application, extract quality, extraction yields and reproducibility.

  19. Transcriptome analyses reveal molecular mechanism underlying tapping panel dryness of rubber tree (Hevea brasiliensis)

    PubMed Central

    Li, Dejun; Wang, Xuncheng; Deng, Zhi; Liu, Hui; Yang, Hong; He, Guangming

    2016-01-01

    Tapping panel dryness (TPD) is a serious threat to natural rubber yields from rubber trees, but the molecular mechanisms underlying TPD remain poorly understood. To identify TPD-related genes and reveal these molecular mechanisms, we sequenced and compared the transcriptomes of bark between healthy and TPD trees. In total, 57,760 assembled genes were obtained and analyzed in details. In contrast to healthy rubber trees, 5652 and 2485 genes were up- or downregulated, respectively, in TPD trees. The TPD-related genes were significantly enriched in eight GO terms and five KEGG pathways and were closely associated with ROS metabolism, programmed cell death and rubber biosynthesis. Our results suggest that rubber tree TPD is a complex process involving many genes. The observed lower rubber yield from TPD trees might result from lower isopentenyl diphosphate (IPP) available for rubber biosynthesis and from downregulation of the genes in post-IPP steps of rubber biosynthesis pathway. Our results not only extend our understanding of the complex molecular events involved in TPD but also will be useful for developing effective measures to control TPD of rubber trees. PMID:27005401

  20. Preparation of steam activated carbon from rubberwood sawdust (Hevea brasiliensis) and its adsorption kinetics.

    PubMed

    Prakash Kumar, B G; Shivakamy, K; Miranda, Lima Rose; Velan, M

    2006-08-25

    Activated carbon was produced from a biowaste product, rubberwood sawdust (RWSD) using steam in a high temperature fluidized bed reactor. Experiments were carried out to investigate the influence of various process parameters such as activation time, activation temperature, particle size and fluidising velocity on the quality of the activated carbon. The activated carbon was characterized based on its iodine number, methylene blue number, Brauner Emmet Teller (BET) surface area and surface area obtained using the ethylene glycol mono ethyl ether (EGME) retention method. The best quality activated carbon was obtained at an activation time and temperature of 1h and 750 degrees C for an average particle size of 0.46 mm. The adsorption kinetics shows that pseudo-second-order rate fitted the adsorption kinetics better than pseudo-first-order rate equation. The adsorption capacity of carbon produced from RWSD was found to be 1250 mg g(-1) for the Bismark Brown dye. The rate constant and diffusion coefficient for intraparticle transport were determined for steam activated carbon. The characteristic of the prepared activated carbon was found comparable to the commercial activated carbon.

  1. Phylogenetic Analysis Reveals a High Prevalence of Sporothrix brasiliensis in Feline Sporotrichosis Outbreaks

    PubMed Central

    Rodrigues, Anderson Messias; de Melo Teixeira, Marcus; de Hoog, G. Sybren; Schubach, Tânia Maria Pacheco; Pereira, Sandro Antonio; Fernandes, Geisa Ferreira; Bezerra, Leila Maria Lopes; Felipe, Maria Sueli; de Camargo, Zoilo Pires

    2013-01-01

    Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics of sporotrichosis occurred in Brazil due to zoonotic transmission, and cats were pointed out as key susceptible hosts. In order to understand the eco-epidemiology of feline sporotrichosis and its role in human sporotrichosis a survey was conducted among symptomatic cats. Prevalence and phylogenetic relationships among feline Sporothrix species were investigated by reconstructing their phylogenetic origin using the calmodulin (CAL) and the translation elongation factor-1 alpha (EF1α) loci in strains originated from Rio de Janeiro (RJ, n = 15), Rio Grande do Sul (RS, n = 10), Paraná (PR, n = 4), São Paulo (SP, n = 3) and Minas Gerais (MG, n = 1). Our results showed that S. brasiliensis is highly prevalent among cats (96.9%) with sporotrichosis, while S. schenckii was identified only once. The genotype of Sporothrix from cats was found identical to S. brasiliensis from human sources confirming that the disease is transmitted by cats. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii. No evidence of recombination in S. brasiliensis was found by split decomposition or PHI-test analysis, suggesting that S. brasiliensis is a clonal species. Strains recovered in states SP, MG and PR share the genotype of the RJ outbreak, different from the RS clone. The occurrence of separate genotypes among strains indicated that the Brazilian S. brasiliensis epidemic has at least two distinct sources. We suggest that cats represent a major host and the main source of cat and human S. brasiliensis infections in Brazil. PMID:23818999

  2. Phylogenetic analysis reveals a high prevalence of Sporothrix brasiliensis in feline sporotrichosis outbreaks.

    PubMed

    Rodrigues, Anderson Messias; de Melo Teixeira, Marcus; de Hoog, G Sybren; Schubach, Tânia Maria Pacheco; Pereira, Sandro Antonio; Fernandes, Geisa Ferreira; Bezerra, Leila Maria Lopes; Felipe, Maria Sueli; de Camargo, Zoilo Pires

    2013-01-01

    Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics of sporotrichosis occurred in Brazil due to zoonotic transmission, and cats were pointed out as key susceptible hosts. In order to understand the eco-epidemiology of feline sporotrichosis and its role in human sporotrichosis a survey was conducted among symptomatic cats. Prevalence and phylogenetic relationships among feline Sporothrix species were investigated by reconstructing their phylogenetic origin using the calmodulin (CAL) and the translation elongation factor-1 alpha (EF1α) loci in strains originated from Rio de Janeiro (RJ, n = 15), Rio Grande do Sul (RS, n = 10), Paraná (PR, n = 4), São Paulo (SP, n =3) and Minas Gerais (MG, n = 1). Our results showed that S. brasiliensis is highly prevalent among cats (96.9%) with sporotrichosis, while S. schenckii was identified only once. The genotype of Sporothrix from cats was found identical to S. brasiliensis from human sources confirming that the disease is transmitted by cats. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii. No evidence of recombination in S. brasiliensis was found by split decomposition or PHI-test analysis, suggesting that S. brasiliensis is a clonal species. Strains recovered in states SP, MG and PR share the genotype of the RJ outbreak, different from the RS clone. The occurrence of separate genotypes among strains indicated that the Brazilian S. brasiliensis epidemic has at least two distinct sources. We suggest that cats represent a major host and the main source of cat and human S. brasiliensis infections in Brazil.

  3. Mitochondrial PCR-RFLP Assay to Distinguish Triatoma brasiliensis macromelasoma from Triatoma brasiliensis brasiliensis Subspecies (Hemiptera: Reduviidae).

    PubMed

    Vendrami, Daniel Pagotto; Ceretti-Junior, Walter; Obara, Marcos Takashi; Marrelli, Mauro Toledo

    2013-01-01

    Triatoma brasiliensis sensu lato (s.l.), the main vector of Chagas disease in northeastern Brazil, is a species complex comprising four species, one with two subspecies (T. brasiliensis brasiliensis, T. brasiliensis macromelasoma, T. juazeirensis, T. sherlocki, and T. melanica), and each taxon displaying distinct ecological requirements. In order to evaluate the genetic relationships among nine T. brasiliensis s.l. populations from northeastern Brazil, we analyzed their mitochondrial cytochrome c oxidase subunit 1 sequences and suggested a PCR-RFLP assay to distinguish between T. b. macromelasoma and T. b. brasiliensis subspecies. All the specimens were morphologically identified as T. b. brasiliensis. The resulting phylogenies identified two major clades that are congruent with the geographical populations studied. Based on collection sites and in accordance with type-location, one clade was identified as the subspecies T. b. macromelasoma. The second clade grouped T. b. brasiliensis populations. Restriction endonuclease sites were observed in the sequences and used in PCR-RFLP assays, producing distinct fingerprints for T. b. macromelasoma and T. b. brasiliensis populations. The results suggest that these are different species and that gene flow occurs only among T. b. brasiliensis populations, possibly associated with human activity in the area.

  4. Ethrel (Ethylene Releaser)-Induced Increases in the Adenylate Pool and Transtonoplast ΔpH within Hevea Latex Cells

    PubMed Central

    Amalou, Zakia; Bangratz, Jacques; Chrestin, Hervé

    1992-01-01

    The treatment of rubber tree (Hevea brasiliensis) bark with chloro-2-ethyl phosphonic acid (ethrel), an ethylene-releasing chemical, induced, after a lag period of 13 to 21 hours, a marked increase in the total adenine nucleotides (essentially ATP and ADP) of latex cells. This rise in the latex adenylate pool was concomitant with a marked decrease in the [ATP]/[ADP] ratio without significant changes in the adenylate energy charge. The apparent equilibrium constant for the adenylate kinase, which appeared to behave as a key enzyme in maintaining the adenylate energy charge in the latex, was considerably reduced, probably as a consequence of the alkalinization of the latex cytosol induced by the treatment with ethrel. To reduce the “sink effect” and activation of the metabolism induced in Hevea bark by regular tapping, the latex was collected by micropuncture (few drops) at increasing distance (5-50 centimeters) above and below an ethrel-treated area on the virgin bark of resting trees. The effect of ethrel was shown to spread progressively along the trunk. The increase in the adenylate pool (essentially ATP) was detectable as early as 24 hours after the bark treatment and was maximum after 6 or 8 days, 5 centimeters as well as 50 centimeters above and below the stimulated bark ring. The correlative vacuolar acidification and cytosolic alkalinization, i.e. the increase in the transtonoplast ΔpH, induced in the latex cells by ethrel were shown to be concomitant with the rise in ATP content of the latex. This suggests that the tonoplast H+-pumping ATPase, which catalyzes vacuolar acidification in the latex, is directly and essentially under the control of the availability of its substrate (i.e. ATP) in the latex. The results are discussed in relation to energy-dependent activation of metabolism, and increased rubber production, as induced by the stimulation of rubber trees with ethrel. PMID:16668787

  5. Monoclonal antibodies to P24 and P61 immunodominant antigens from Nocardia brasiliensis.

    PubMed

    Salinas-Carmona, M C; Castro-Corona, M A; Sepúlveda-Saavedra, J; Perez, L I

    1997-03-01

    We prepared a Nocardia brasiliensis cell extract and purified two immunodominant antigens with molecular weights of 61,000 and 24,000. The isolated proteins were shown to be reasonably pure when analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (8 to 18% polyacrylamide gradient) and stained with Coomassie blue and silver nitrate. By using an immunoelectrotransfer blot method (Western blotting), we demonstrated that these two purified proteins reacted strongly with serum from N. brasiliensis-infected mycetoma patients. To obtain anti-P61 and anti-P24 monoclonal antibodies (MAbs), we used an N. brasiliensis cell extract as the antigen for the first immunization; 2 weeks later female mice were reimmunized with a semipurified antigen containing the P24 or P61 fraction. A booster injection was given 3 days before the fusion was carried out. Two hybrids that reacted strongly with P24 were cloned by limiting dilution, the generated MAbs were analyzed for isotyping, and their specificity was tested in a Western blot assay with cell extracts from Nocardia asteroides and Mycobacterium tuberculosis cultures. Anti-P24 MAbs were shown to be specific for N. brasiliensis HUJEG-1 and did not cross-react with either the N. asteroides or M. tuberculosis strains used. However, additional studies with several N. asteroides and N. brasiliensis strains are needed to investigate whether there are cross-reactions between strains or species when these MAbs are used. The anti-P61 and anti-24 MAbs were used to locate the antigen in N. brasiliensis cells by immunofluorescence. The lack of reaction with intact cells suggests that the P24 and P61 antigens are not exposed in the complete bacterial cell surface or that the recognized epitopes are different. Only one anti-P61 MAb that reacted specifically with the N. brasiliensis cell extract was obtained.

  6. Monoclonal antibodies to P24 and P61 immunodominant antigens from Nocardia brasiliensis.

    PubMed Central

    Salinas-Carmona, M C; Castro-Corona, M A; Sepúlveda-Saavedra, J; Perez, L I

    1997-01-01

    We prepared a Nocardia brasiliensis cell extract and purified two immunodominant antigens with molecular weights of 61,000 and 24,000. The isolated proteins were shown to be reasonably pure when analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (8 to 18% polyacrylamide gradient) and stained with Coomassie blue and silver nitrate. By using an immunoelectrotransfer blot method (Western blotting), we demonstrated that these two purified proteins reacted strongly with serum from N. brasiliensis-infected mycetoma patients. To obtain anti-P61 and anti-P24 monoclonal antibodies (MAbs), we used an N. brasiliensis cell extract as the antigen for the first immunization; 2 weeks later female mice were reimmunized with a semipurified antigen containing the P24 or P61 fraction. A booster injection was given 3 days before the fusion was carried out. Two hybrids that reacted strongly with P24 were cloned by limiting dilution, the generated MAbs were analyzed for isotyping, and their specificity was tested in a Western blot assay with cell extracts from Nocardia asteroides and Mycobacterium tuberculosis cultures. Anti-P24 MAbs were shown to be specific for N. brasiliensis HUJEG-1 and did not cross-react with either the N. asteroides or M. tuberculosis strains used. However, additional studies with several N. asteroides and N. brasiliensis strains are needed to investigate whether there are cross-reactions between strains or species when these MAbs are used. The anti-P61 and anti-24 MAbs were used to locate the antigen in N. brasiliensis cells by immunofluorescence. The lack of reaction with intact cells suggests that the P24 and P61 antigens are not exposed in the complete bacterial cell surface or that the recognized epitopes are different. Only one anti-P61 MAb that reacted specifically with the N. brasiliensis cell extract was obtained. PMID:9067645

  7. Primers for Clinical Detection of Paracoccidioides brasiliensis

    PubMed Central

    San-Blas, Gioconda; Niño-Vega, Gustavo; Barreto, Laura; Hebeler-Barbosa, Flavia; Bagagli, Eduardo; Olivero de Briceño, Rosa; Mendes, Rinaldo Poncio

    2005-01-01

    From a 0.72-kb fragment universally generated in Paracoccidioides brasiliensis strains, primers were designed and tested on genomic DNA of this and other pathogenic fungi. They were specific and highly sensitive for P. brasiliensis DNA. Positive results were obtained when these were tested in clinical samples. PMID:16081993

  8. Molecular detection and identification of Paracoccidioides brasiliensis.

    PubMed Central

    Sandhu, G S; Aleff, R A; Kline, B C; da Silva Lacaz, C

    1997-01-01

    Nearly 800 nucleotides from the 5' terminus of the 28S ribosomal gene of Paracoccidioides brasiliensis were sequenced, and a 14-base DNA probe specific for this species was identified. Hybridization results showed that the probe identified P. brasiliensis ribosomal DNA in a panel of ribosomal DNAs representing a total of 48 species of fungi. PMID:9196219

  9. Nocardia brasiliensis: mycetoma induction and growth cycle.

    PubMed Central

    Conde, C; Melendro, E I; Fresán, M; Ortiz-Ortiz, L

    1982-01-01

    The capacity of Nocardia brasiliensis to induce mycetoma in BALB/c mice in the absence of adjuvants was studied. Whether the virulence of N. brasiliensis varied in the different phases of its growth cycle was also determined. The results showed that N. brasiliensis suspended in 0.15 M NaCl and injected into the footpads of mice were able to induce mycetoma after only 14 days of infection, as evidenced by histological studies. Data are also presented indicating that the virulence of N. brasiliensis did not vary during the different phases of its growth curve. The differences in virulence reported between N. brasiliensis and other nocardiae are discussed and explained in terms of several variables in the experimental designs used: among these variables are mouse genotype, route of inoculation, and model for determining virulence. Images PMID:7152671

  10. Expression of Nocardia brasiliensis superoxide dismutase during the early infection of murine peritoneal macrophages.

    PubMed

    Revol, Agnès; Espinoza-Ruiz, Marisol; Medina-Villanueva, Igor; Salinas-Carmona, Mario Cesar

    2006-12-01

    Nocardia brasiliensis is the main agent of actinomycetoma in Mexico, but little is known about its virulence and molecular pathogenic pathways. These facultative intracellular bacteria are able to survive and divide within the host phagocytic cells, in part by neutralizing the reactive oxygen intermediates. Superoxide dismutase (SOD) participates in the intracellular survival of several bacterial species and, in particular, constitutes one of Nocardia asteroides virulence factors. To clarify SOD participation in the N. brasiliensis early infective process, we report its isolation and the consequent comparison of its transcript level. A 630 bp polymerase chain reaction fragment that included most of the coding sequence of N. brasiliensis sodA was cloned. A competitive assay was developed, allowing comparison of bacterial sod expression in exponential culture and 1 h after infecting peritoneal macrophages from BALB/c mice. At that time, there were viable bacteria in the macrophages. The intracellular bacteria presented a clear decrease in their sod transcript amount, although their 16S rRNA (used as an internal control) and hsp levels were maintained or slightly increased, respectively. These results indicate that sodA transcription is not maintained within the SOS bacterial response induced by phagosomal conditions. Further kinetics will be necessary to precisely define sod transcriptional regulation during N. brasiliensis intra-macrophage growth.

  11. Lymphocutaneous nocardiosis due to Nocardia brasiliensis.

    PubMed

    Maraki, Sofia; Scoulica, Efstathia; Alpantaki, Kalliopi; Dialynas, Michael; Tselentis, Yannis

    2003-09-01

    Nocardia species are Gram-positive bacteria responsible for systemic or cutaneous infections in humans. Nocardia brasiliensis is the most common infective agent in the cutaneous form of nocardiosis. We describe a case of a previously healthy man, who presented with lymphocutaneous Nocardia brasiliensis infection, and was successfully treated with trimethoprim-sulfamethoxazole. The identification of the isolate was confirmed by nucleotide sequence analysis of the 16S rRNA gene.

  12. NLRP3 Inflammasome Activation by Paracoccidioides brasiliensis

    PubMed Central

    Almeida, Raquel Das Neves; Correa, Rafael; Burgel, Pedro Henrique; Bocca, Anamélia Lorenzetti

    2013-01-01

    Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), the most prevalent systemic mycosis that is geographically confined to Latin America. The pro-inflammatory cytokine IL-1β that is mainly derived from the activation of the cytoplasmic multiprotein complex inflammasome is an essential host factor against opportunistic fungal infections; however, its role in infection with a primary fungal pathogen, such as P. brasiliensis, is not well understood. In this study, we found that murine bone marrow-derived dendritic cells responded to P. brasiliensis yeast cells infection by releasing IL-1β in a spleen tyrosine kinase (Syk), caspase-1 and NOD-like receptor (NLR) family member NLRP3 dependent manner. In addition, P. brasiliensis-induced NLRP3 inflammasome activation was dependent on potassium (K+) efflux, reactive oxygen species production, phagolysosomal acidification and cathepsin B release. Finally, using mice lacking the IL-1 receptor, we demonstrated that IL-1β signaling has an important role in killing P. brasiliensis by murine macrophages. Altogether, our results demonstrate that the NLRP3 inflammasome senses and responds to P. brasiliensis yeast cells infection and plays an important role in host defense against this fungus. PMID:24340123

  13. Identification of Paracoccidioides brasiliensis by gold nanoprobes

    NASA Astrophysics Data System (ADS)

    Martins, Jaciara F. S.; Castilho, Maiara L.; Cardoso, Maria A. G.; Carreiro, Andrea P.; Martin, Airton A.; Raniero, Leandro

    2012-01-01

    Paracoccidioides brasiliensis (P. brasiliensis) is a thermal dimorphic fungus and causal agent of paracoccidioidomycosis. Epidemiological data shows that it is mainly concentrated in Central and South America countries, with most registered cases in Colombia, Brazil, and Venezuela. The histopathological similarity with others fungal infection makes the diagnosis of P. brasiliensis more complicated. Therefore, the aim of this work was to find a positive and negative test for P. brasiliensis using gold nanoprobes as a new tool for P. brasiliensis detection. Gold nanoparticles were synthesized by reduction of gold chloride with sodium citrate. The results of this procedure is a wine-red solution with a maximum absorption in the range of ~520-530nm. A specific P. brasiliensis sequence of oligonucleotide was bonded to the nanoparticles, which maintained the wine-red color. The color changes from red to blue for negative diagnostic and is unchanged for a positive test. The H-bond interaction of DNA with the complementary DNA keeps strands together and forms double helical structure, maintaining the colloid stability. However, for non-complimentary DNA sequence the nanoprobes merge into a cluster, changing the light absorption.

  14. Solubilization and purification of the ATPase from the tonoplast of Hevea.

    PubMed

    Marin, B; Preisser, J; Komor, E

    1985-08-15

    The tonoplast-bound ATPase of Hevea brasiliensis (caoutchouc tree) was solubilized with dichloromethan and purified 100-fold with two ammonium sulfate precipitation steps and a G-200 gel filtration step. The resulting ATPase activity eluted according to a molecular mass of approximately 200 kDa and chromatographed at an isoelectric pH of 5.3. Subunits of molecular mass 110 kDa, 68 kDa, 24 kDa and 12 kDa appeared after treatment with 1% sodium dodecyl sulfate or spontaneously during storage of the solubilized ATPase. Dodecyl sulfate/polyacrylamide gel electrophoresis yielded four polypeptides of molecular mass 54 kDa, 66 kDa, 23 kDa and 13 kDa. From protein determination by ultraviolet absorption and Coomassie stain it appears that the 54-kDa and the 66-kDa polypeptides exist in multiple copies. No close resemblance to the membrane-bound ATPase of mitochondria, plastids, plasmalemma, chromaffin granules and synaptic vesicles is seen. No antibody cross-reaction to F1 of bacteria is observed. Therefore it is concluded that the vacuolar ATPase represents a novel type of ATPase. Many properties of the tonoplast-bound ATPase such as pH-dependence, substrate specificity, ion-dependence and inhibitor sensitivity did not change when the enzyme had been solubilized and purified. The phosphatase activity was lost during the purification procedure. The stimulation of ATP-hydrolysis in tonoplast vesicles by uncouplers and ionophores was absent in the solubilized ATPase, and also the stimulation by chloride was significantly reduced. Anion channel blockers, such as triphenyltin and 4,4'-diisothiocyano-2,2'-disulfonic acid stilbene, which are strong inhibitors of membrane-bound ATPase, fully or partly lost their inhibiting effect after solubilization of the ATPase. These results are interpreted to indicate that ionophores do not directly affect the ATPase molecule, whereas chloride might have a small direct effect on the ATPase besides its effect as a permeating anion.

  15. Optimisation on pretreatment of rubber seed (Hevea brasiliensis) oil via esterification reaction in a hydrodynamic cavitation reactor.

    PubMed

    Bokhari, Awais; Chuah, Lai Fatt; Yusup, Suzana; Klemeš, Jiří Jaromír; Kamil, Ruzaimah Nik M

    2016-01-01

    Pretreatment of the high free fatty acid rubber seed oil (RSO) via esterification reaction has been investigated by using a pilot scale hydrodynamic cavitation (HC) reactor. Four newly designed orifice plate geometries are studied. Cavities are induced by assisted double diaphragm pump in the range of 1-3.5 bar inlet pressure. An optimised plate with 21 holes of 1mm diameter and inlet pressure of 3 bar resulted in RSO acid value reduction from 72.36 to 2.64 mg KOH/g within 30 min of reaction time. Reaction parameters have been optimised by using response surface methodology and found as methanol to oil ratio of 6:1, catalyst concentration of 8 wt%, reaction time of 30 min and reaction temperature of 55°C. The reaction time and esterified efficiency of HC was three fold shorter and four fold higher than mechanical stirring. This makes the HC process more environmental friendly.

  16. Solubilization and Reconstitution of the Mg2+/2H+ Antiporter of the Lutoid Tonoplast from Hevea brasiliensis Latex.

    PubMed Central

    Amalou, Z.; Gibrat, R.; Trouslot, P.; D'Auzac, J.

    1994-01-01

    The Mg2+/2H+ antiporter recently described on lutoid membrane (Z. Amalou, R. Gibrat, C. Brugidou, P. Trouslot, J.d'Auzac [1992] Plant Physiol 100: 255-260) was solubilized by octylglucoside and reconstituted into soybean liposomes using the detergent dilution method. Magnesium efflux or influx experiments were used to generate a H+ influx or efflux, respectively, monitored with the fluorescent probe 9-amino-6-chloro-2-methoxyacridine. Both experiments gave saturable H+ fluxes as a function of internal or external Mg2+ concentrations with similar kinetic parameters Km and Vmax. The Km value for Mg2+ (about 2 mM) was identical to that previously found in lyophilized-resuspended lutoid (reference therein), whereas the Vmax value was 14-fold higher. Since only 10% of the initial proteins were recovered in proteoliposomes, and electrophoretic patterns of the two kinds of vesicles differed significantly, it was inferred that the increase in Vmax was due essentially to an enrichment of the protein antiporter in the reconstituted fraction, owing to a selective effect of octylglucoside at both solubilization and reconstitution steps. None of the various divalent cations used could dissipate the pH gradient of control liposomes of soybean lipids, unless the divalent/H+ exchanger A23187 was added, whereas a rapid dissipation of the pH gradient was observed with reconstituted proteoliposomes from lutoid proteins, with the cation selectivity sequence Zn2+ > Cd2+ > Mg2+ in the millimolar concentration range. The divalent ions Ca2+, Ba2+, and Mn2+ were incapable of generating a H+ efflux in reconstituted proteoliposomes, whereas both Mg2+/H+ and Ca2+/H+ exchanges were observed in lyophilized-resuspended lutoids. Therefore, the lutoid membrane seems to contain separate Mg2+/H+ and Ca2+/H transport systems, the latter being eliminated during the solubilization/reconstitution of lutoid membrane proteins. PMID:12232305

  17. Oxidative stress response in Paracoccidioides brasiliensis.

    PubMed

    Campos, Elida G; Jesuino, Rosália Santos Amorim; Dantas, Alessandra da Silva; Brígido, Marcelo de Macedo; Felipe, Maria Sueli S

    2005-06-30

    Survival of pathogenic fungi inside human hosts depends on evasion from the host immune system and adaptation to the host environment. Among different insults that Paracoccidioides brasiliensis has to handle are reactive oxygen and nitrogen species produced by the human host cells, and by its own metabolism. Knowing how the parasite deals with reactive species is important to understand how it establishes infection and survives within humans. The initiative to describe the P. brasiliensis transcriptome fostered new approaches to study oxidative stress response in this organism. By examining genes related to oxidative stress response, one can evaluate the parasite's ability to face this condition and infer about possible ways to overcome this ability. We report the results of a search of the P. brasiliensis assembled expressed sequence tag database for homologous sequences involved in oxidative stress response. We described several genes coding proteins involved in antioxidant defense, for example, catalase and superoxide dismutase isoenzymes, peroxiredoxin, cytochrome c peroxidase, glutathione synthesis enzymes, thioredoxin, and the transcription factors Yap1 and Skn7. The transcriptome analysis of P. brasiliensis reveals a pathogen that has many resources to combat reactive species. Besides characterizing the antioxidant defense system in P. brasiliensis, we also compared the ways in which different fungi respond to oxidative damage, and we identified the basic features of this response.

  18. Sensitivity of Tonoplast-Bound Adenosine-Triphosphatase from Hevea to Inhibitors 1

    PubMed Central

    Marin, Bernard

    1983-01-01

    The tonoplast-bound H+-translocating ATPase from Hevea latex was found to be insensitive to vanadate, diethylstilbestrol, and octylguanidine, which are specific inhibitors of the plasma membrane ATPase. The inhibitors of the mitochondrial ATPase, oligomycin and azide, and also rotenone and antimycin A, were all without effect. In contrast, trimethyltin chloride strongly inhibited the activity of Hevea tonoplast ATPase. Among the different carbodiimides tested, which strongly inhibit the Hevea tonoplast ATPase, N,N′-dicyclohexylcarbodiimide was the most inhibitory. N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline was also an efficient inhibitor. This unique inhibitor sensitivity of the Hevea tonoplast H+-translocating ATPase suggests that this enzyme differs in its mode of operation from all other known H+-translocating ATPases. PMID:16663354

  19. Characterization of PbPga1, an Antigenic GPI-Protein in the Pathogenic Fungus Paracoccidioides brasiliensis

    PubMed Central

    Valim, Clarissa X. R.; Basso, Luiz Roberto; dos Reis Almeida, Fausto B.; Reis, Thaila Fernanda; Damásio, André Ricardo Lima; Arruda, Luisa Karla; Martinez, Roberto; Roque-Barreira, Maria Cristina; Oliver, Constance; Jamur, Maria Célia; Coelho, Paulo Sergio Rodrigues

    2012-01-01

    Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), one of the most prevalent mycosis in Latin America. P. brasiliensis cell wall components interact with host cells and influence the pathogenesis of PCM. Cell wall components, such as glycosylphosphatidylinositol (GPI)-proteins play a critical role in cell adhesion and host tissue invasion. Although the importance of GPI-proteins in the pathogenesis of other medically important fungi is recognized, little is known about their function in P. brasiliensis cells and PCM pathogenesis. We cloned the PbPga1 gene that codifies for a predicted GPI-anchored glycoprotein from the dimorphic pathogenic fungus P. brasiliensis. PbPga1 is conserved in Eurotiomycetes fungi and encodes for a protein with potential glycosylation sites in a serine/threonine-rich region, a signal peptide and a putative glycosylphosphatidylinositol attachment signal sequence. Specific chicken anti-rPbPga1 antibody localized PbPga1 on the yeast cell surface at the septum between the mother cell and the bud with stronger staining of the bud. The exposure of murine peritoneal macrophages to rPbPga1 induces TNF-α release and nitric oxide (NO) production by macrophages. Furthermore, the presence of O-glycosylation sites was demonstrated by β-elimination under ammonium hydroxide treatment of rPbPga1. Finally, sera from PCM patients recognized rPbPga1 by Western blotting indicating the presence of specific antibodies against rPbPga1. In conclusion, our findings suggest that the PbPga1gene codifies for a cell surface glycoprotein, probably attached to a GPI-anchor, which may play a role in P. brasiliensis cell wall morphogenesis and infection. The induction of inflammatory mediators released by rPbPga1 and the reactivity of PCM patient sera toward rPbPga1 imply that the protein favors the innate mechanisms of defense and induces humoral immunity during P. brasiliensis infection. PMID:23024763

  20. Overinfection by Paracoccidioides brasiliensis in Gouty Crystal Arthritis

    PubMed Central

    Bonilla-Abadía, F.; Vélez, J. D.; Zárate-Correa, L. C.; Carrascal, E.; Guarín, N.; Castañeda-Ramírez, C. R.; Cañas, C. A.

    2012-01-01

    Paracoccidioidomycosis is an endemic South American systemic mycosis caused by the dimorphic fungus Paracoccidioides brasiliensis (P. brasiliensis). The main clinical form of disease is pulmonary, but all organs may be involved. We report a case of overinfection by P. brasiliensis in chronic gouty arthritis affecting the proximal phalanx of the right hallux. The patient required proximal amputation and long-term antifungal therapy. PMID:23251162

  1. Nocardia brasiliensis Infection Complicating Cryptogenic Organizing Pneumonia

    PubMed Central

    Fernandes, Alison M.; Sluzevich, Jason C.

    2017-01-01

    Pulmonary nocardiosis is a severe and uncommon opportunistic infection caused by Nocardia species. We present a patient with cryptogenic organizing pneumonia who was receiving long-term immunosuppressive therapy, whose treatment course was complicated by cutaneous and pulmonary nocardiosis. Tissue cultures confirmed Nocardia brasiliensis. Nocardiosis should be a diagnostic consideration for patients treated with long-term immunosuppression who have worsening pulmonary symptoms and relapsing pustular skin lesions. PMID:28348912

  2. Nocardia brasiliensis Infection Complicating Cryptogenic Organizing Pneumonia.

    PubMed

    Fernandes, Alison M; Sluzevich, Jason C; Mira-Avendano, Isabel

    2017-01-01

    Pulmonary nocardiosis is a severe and uncommon opportunistic infection caused by Nocardia species. We present a patient with cryptogenic organizing pneumonia who was receiving long-term immunosuppressive therapy, whose treatment course was complicated by cutaneous and pulmonary nocardiosis. Tissue cultures confirmed Nocardia brasiliensis. Nocardiosis should be a diagnostic consideration for patients treated with long-term immunosuppression who have worsening pulmonary symptoms and relapsing pustular skin lesions.

  3. Nuclear staining of Paracoccidioides brasiliensis conidia.

    PubMed

    McEwen, J G; Restrepo, B I; Salazar, M E; Restrepo, A

    1987-10-01

    More than 80% of the conidia produced by two different isolates of Paracoccidioides brasiliensis, were found to be uninucleate; however, when they were incubated at 37 degrees C and began to transform into yeast cells, they became bi- or multi-nucleated, so that when most of the conidia had already transformed into yeast cells (72-96 h), there were at least four or five nuclei per cell in approximately 80% of the conidia examined.

  4. Paracoccidioides brasiliensis Infection in Small Wild Mammals.

    PubMed

    Sbeghen, Mônica Raquel; Zanata, Thais Bastos; Macagnan, Rafaela; de Abreu, Kaue Cachuba; da Cunha, Willian Luiz; Watanabe, Maria Angelica Ehara; de Camargo, Zoilo Pires; Ono, Mario Augusto

    2015-12-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis prevalent in Brazil and other Latin American countries. The etiological agents of PCM are the thermo-dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. Taking into account that the natural habitat of Paracoccidioides spp. is still undefined, domestic and wild animals could be useful as indicators of Paracoccidioides spp. presence in endemic areas. The objective of this study was to evaluate the infection of small wild mammals by P. brasiliensis in an endemic area for human PCM. Samples from 38 wild mammals from different species such as Akodon sp., Thaptomys nigrita, Euryoryzomys russatus, Oligoryzomys nigripes, Monodelphis sp., Sooretamys angouya, Abrawayaomys angouya, Abrawayaomys ruschii and Akodontinae sp. were evaluated by ELISA, immunodiffusion, histopathology, nested PCR and culture. The overall positivity to gp43 observed in the ELISA was 23.7%. Samples from heart and liver of one O. nigripes were PCR positive, and the animal was also seropositive to gp43 in ELISA. This study showed that wild animals living in endemic areas for PCM are infected with P. brasiliensis and can be valuable epidemiological markers of the fungus presence in the environment. This is the first evidence of PCM infection in Akodon sp., E. russatus, T. nigrita and O. nigripes.

  5. Bioinformatics of the Paracoccidioides brasiliensis EST Project.

    PubMed

    Brígido, Marcelo M; Walter, Maria Emília M T; Oliveira, Adilton G; Inoue, Marcus K; Anjos, Daniel S; Sandes, Edans F O; Gondim, João J; Carvalho, Maria José de A; Almeida, Nalvo F; Felipe, Maria Sueli Soares

    2005-06-30

    Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, an endemic mycosis of Latin America. This fungus presents a dimorphic character; it grows as a mycelium at room temperature, but it is isolated as yeast from infected individuals. It is believed that the transition from mycelium to yeast is important for the infective process. The Functional and Differential Genome of Paracoccidioides brasiliensis Project--PbGenome Project was developed to study the infection process by analyzing expressed sequence tags--ESTs, isolated from both mycelial and yeast forms. The PbGenome Project was executed by a consortium that included 70 researchers (professors and students) from two sequencing laboratories of the midwest region of Brazil; this project produced 25,741 ESTs, 19,718 of which with sufficient quality to be analyzed. We describe the computational procedures used to receive process, analyze these ESTs, and help with their functional annotations; we also detail the services that were used for sequence data exploration. Various programs were compared for filtering and grouping the sequences, and they were adapted to a user-friendly interface. This system made the analysis of the differential transcriptome of P. brasiliensis possible.

  6. Characterization of a chaperone ClpB homologue of Paracoccidioides brasiliensis.

    PubMed

    Jesuino, Rosália S A; Azevedo, Maristela O; Felipe, M Sueli S; Pereira, Maristela; De Almeida Soares, Célia M

    2002-08-01

    We report the cloning and sequence analysis of a genomic clone encoding a Paracoccidioides brasiliensis ClpB chaperone homologue (PbClpB). The clpb gene was identified in a lambda Dash II library. Sequencing of Pbclpb revealed a long open reading frame capable of encoding a 792 amino acid, 87.9 kDa protein, pI of 5.34. The predicted polypeptide contains several consensus motifs of the ClpB proteins. Canonical sequences such as two putative nucleotide-binding sites, chaperonins ClpA/B signatures and highly conserved casein kinase phosphorylation domains are present. ClpB is 69% to 49% identical to members of the ClpB family from several organisms from prokaryotes to eukaryotes. The transcript of PbclpB was detected as a mRNA species of 3.0 kb, preferentially expressed in the yeast parasitic phase of the fungus. A 89 kDa protein was also detected in yeast cells of P. brasiliensis.

  7. Complete Genome Sequence of Nocardia brasiliensis HUJEG-1

    PubMed Central

    Ortiz-Lopez, Rocio; Elizondo-Gonzalez, Ramiro; Perez-Maya, Antonio Ali; Ocampo-Candiani, Jorge

    2012-01-01

    In Mexico, actinomycetoma is mainly caused by Nocardia brasiliensis, which is a soil inhabitant actinobacterium. Here, we report for the first time the draft genome of a strain isolated from a human case that has largely been found in in vitro and experimental models of actinomycetoma, N. brasiliensis HUJEG-1. PMID:22535940

  8. Thyroid peroxidase inhibition by Kalanchoe brasiliensis aqueous extract.

    PubMed

    Ferreira, A C; Rosenthal, D; Carvalho, D P

    2000-05-01

    Flavonoids are known inhibitors of thyroid peroxidase (TPO) and some are components of Kalanchoe brasiliensis, a plant used in popular medicine to treat tissue injuries, enlarged ganglia and peptic ulcer. As K. brasiliensis extract is currently used, the present study was designed to evaluate the effects of K. brasiliensis aqueous extract on TPO activity. We show here that TPO iodide-oxidation activity was significantly inhibited by K. brasiliensis aqueous extract and that TPO inhibition seems to be competitive, since the enzyme V(max) was unchanged and K(m) for iodide was significantly increased in the presence of the plant extract. Furthermore, TPO inhibitory activity produced by K. brasiliensis extract was unchanged after boiling or by incubation with hepatic enzymes (activated S9 fraction), suggesting that at least the antithyroid component of this plant infusion could probably reach systemic circulation. We also report that K. brasiliensis aqueous extract is able to scavenge H(2)O(2), in vitro. As H(2)O(2) is an essential TPO cofactor, it is possible that the H(2)O(2) trapping effect of K. brasiliensis may be responsible, at least in part, for the inhibition of the iodide-oxidation reaction catalysed by this enzyme. Thus, K. brasiliensis aqueous extract has antithyroid effects in vitro, suggesting that its chronic consumption could contribute to the development of goitre and hypothyroidism, mainly in areas of low iodine intake.

  9. Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea

    PubMed Central

    Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

    2014-01-01

    The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

  10. Cutaneous Granulomas in Dolphins Caused by Novel Uncultivated Paracoccidioides brasiliensis

    PubMed Central

    Vilela, Raquel; Bossart, Gregory D.; St. Leger, Judy A.; Dalton, Leslie M.; Reif, John S.; Schaefer, Adam M.; McCarthy, Peter J.; Fair, Patricia A.

    2016-01-01

    Cutaneous granulomas in dolphins were believed to be caused by Lacazia loboi, which also causes a similar disease in humans. This hypothesis was recently challenged by reports that fungal DNA sequences from dolphins grouped this pathogen with Paracoccidioides brasiliensis. We conducted phylogenetic analysis of fungi from 6 bottlenose dolphins (Tursiops truncatus) with cutaneous granulomas and chains of yeast cells in infected tissues. Kex gene sequences of P. brasiliensis from dolphins showed 100% homology with sequences from cultivated P. brasiliensis, 73% with those of L. loboi, and 93% with those of P. lutzii. Parsimony analysis placed DNA sequences from dolphins within a cluster with human P. brasiliensis strains. This cluster was the sister taxon to P. lutzii and L. loboi. Our molecular data support previous findings and suggest that a novel uncultivated strain of P. brasiliensis restricted to cutaneous lesions in dolphins is probably the cause of lacaziosis/lobomycosis, herein referred to as paracoccidioidomycosis ceti. PMID:27869614

  11. Protein influences on guayule and Hevea natural rubber sol and gel

    USDA-ARS?s Scientific Manuscript database

    Guayule (Parthenium argentatum) is under cultivation in the southwestern United States as an alternative source of natural rubber free from proteins that cause Type I latex allergies. However, since guayule lacks the protein-polymer interactions present in Hevea latex, its physical and chemical prop...

  12. Potent Schistosomicidal Constituents from Garcinia brasiliensis.

    PubMed

    Castro, Aline Pereira; de Mattos, Ana Carolina Alves; Pereira, Neusa Araújo; Anchieta, Naira Ferreira; Silva, Matheus Siqueira; Dias, Danielle Ferreira; Silva, Claudinei Alves; Barros, Giulliano Vilela; Souza, Raquel Lopes Martins; Dos Santos, Marcelo Henrique; Marques, Marcos José

    2015-06-01

    Praziquantel is the drug of choice for the treatment of schistosomiasis. However, several strains of Schistosoma mansoni are resistant to praziquantel, making it necessary to discover new drugs that might be used for its treatment. With this in mind, the properties of a schistosomicidal ethanolic extract of Garcinia brasiliensis Mart. epicarp, the fractions obtained by partitioning this extract, including the hexane fractions, ethyl acetate fraction, and the aqueous fraction, and the isolated compounds 7-epiclusianone, a major component from these fractions, and fukugetin were tested in vitro on adult worms of S. mansoni. Mortality, damage to membranes, and excretory system activity were observed at 100.0, 50.0, 75.0, and 14.0 µg/mL for the ethanolic extract of G. brasiliensis Mart. epicarp, its hexane fractions, the ethyl acetate fraction, and 7-epiclusianone, respectively. For 7-epiclusianone, these data were confirmed by fluorescent probe Hoechst 33 258 and resorufin. Additionally, the biocidal effect of 7-epiclusianone was even higher than the hexane fractions. Moreover, an inhibitory effect of 7-epiclusianone on the egg laying of female adult S. mansoni worms was observed in cercariae and schistossomula. Thus, 7-epiclusianone is a promising schistosomicidal compound; however, more studies are needed to elucidate its mechanism of toxicity and to evaluate the in vivo activity of this compound.

  13. Involvement of an Alternative Oxidase in Oxidative Stress and Mycelium-to-Yeast Differentiation in Paracoccidioides brasiliensis ▿ †

    PubMed Central

    Martins, Vicente P.; Dinamarco, Taisa M.; Soriani, Frederico M.; Tudella, Valéria G.; Oliveira, Sergio C.; Goldman, Gustavo H.; Curti, Carlos; Uyemura, Sérgio A.

    2011-01-01

    Paracoccidioides brasiliensis is a thermodimorphic human pathogenic fungus that causes paracoccidioidomycosis (PCM), which is the most prevalent systemic mycosis in Latin America. Differentiation from the mycelial to the yeast form (M-to-Y) is an essential step for the establishment of PCM. We evaluated the involvement of mitochondria and intracellular oxidative stress in M-to-Y differentiation. M-to-Y transition was delayed by the inhibition of mitochondrial complexes III and IV or alternative oxidase (AOX) and was blocked by the association of AOX with complex III or IV inhibitors. The expression of P. brasiliensis aox (Pbaox) was developmentally regulated through M-to-Y differentiation, wherein the highest levels were achieved in the first 24 h and during the yeast exponential growth phase; Pbaox was upregulated by oxidative stress. Pbaox was cloned, and its heterologous expression conferred cyanide-resistant respiration in Saccharomyces cerevisiae and Escherichia coli and reduced oxidative stress in S. cerevisiae cells. These results reinforce the role of PbAOX in intracellular redox balancing and demonstrate its involvement, as well as that of other components of the mitochondrial respiratory chain complexes, in the early stages of the M-to-Y differentiation of P. brasiliensis. PMID:21183691

  14. Characterization of a gene which encodes a mannosyltransferase homolog of Paracoccidioides brasiliensis.

    PubMed

    Costa, Alessandra A; Gómez, Francisco J; Pereira, Maristela; Felipe, M Sueli S; Jesuino, Rosália S A; Deepe, George S; de Almeida Soares, Célia M

    2002-08-01

    We screened an expression library of the yeast form of Paracoccidioides brasiliensis with a pool of human sera that was pre-adsorbed with mycelium, from patients with paracoccidioidomycosis (PCM). A sequence (PbYmnt) was obtained and characterized. A genomic clone was obtained by PCR of P. brasiliensis total DNA. The sequence contained a single open reading frame (ORF) encoding a protein of 357 amino acid residues, with a molecular mass of 39.78 kDa. The deduced amino acid sequence exhibited identity to mannosyl- and glycosyltransferases from several sources. A DXD motif was present in the translated gene and this sequence is characteristic of the glycosyltransferases. Hydropathy analysis revealed a single transmembrane region near the amino terminus of the molecule that suggested a type II membrane protein. The PbYmnt was expressed preferentially in the yeast parasitic phase. The accession number of the nucleotide sequence of PbYmnt and its flanking regions is AF374353. A recombinant protein was generated in Escherichia coli. Our data suggest that PbYmnt encodes one member of a glycosyltransferase family of proteins and that our strategy was useful in the isolation of differentially expressed genes.

  15. Immunohistochemical detection of a novel 22- to 25-kilodalton glycoprotein of Paracoccidioides brasiliensis in biopsy material and partial characterization by using species-specific monoclonal antibodies.

    PubMed Central

    Figueroa, J I; Hamilton, A; Allen, M; Hay, R

    1994-01-01

    Two murine monoclonal antibodies (MAbs) specific to Paracoccidioides brasiliensis (as determined by enzyme-linked immunosorbent assay [ELISA] and Western blot [immunoblot]) were produced by using a modification of standard hybridization protocols, with cyclophosphamide included as an immunomodulator to abolish responses to highly cross-reactive immunodominant epitopes. MAbs PS14 and PS15 are two different clones which exhibit similar characteristics by ELISA and Western blot. They are directed against a 22- to 25-kDa antigen which is present in P. brasiliensis and which could not be identified in other dimorphic fungi by ELISA or Western blot. Partial purification of the antigen was accomplished by isoelectric focusing, and deglycosylation studies suggested that the 22- to 25-kDa antigen is a glycoprotein with a pI of between 4.5 and 5 and that O-linked sugars may be part of the recognized epitope. The MAbs stained the cytoplasm of P. brasiliensis yeast and hyphal cells in cryostat sections of fresh cultures of the fungus. In addition, the MAbs stained the wall of paracoccidioidomycotic granulomas, as well as the cytoplasm of the fungus, as determined by the use of immunofluorescence, immunoperoxidase, and immuno-alkaline phosphatase staining techniques in paraffin-embedded sections of human biopsy material, and they failed to stain granulomas resulting from other clinical conditions. These findings suggest that these MAbs have potential use in the immunohistochemical identification of P. brasiliensis. Images PMID:8077405

  16. Subtractive phage display selection for screening and identification of peptide sequences with potential use in serodiagnosis of paracoccidioidomycosis caused by Paracoccidioides brasiliensis.

    PubMed

    Portes, L da Silva; Kioshima, E S; de Camargo, Z P; Batista, W L; Xander, P

    2017-08-10

    Paracoccidioidomycosis (PCM) is a systemic granulomatous disease endemic in Latin America whose aetiologic agents are the thermodimorphic fungi Paracoccidioides brasiliensis and Paracoccidioides lutzii. Despite technological advances, some problems have been reported for the fungal antigens used for serological diagnosis, and inconsistencies among laboratories have been reported. The use of synthetic peptides in the serological diagnosis of infectious diseases has proved to be a valuable strategy because in some cases, the reactions are more specific and sensitive. In this study, we used a subtractive selection with a phage display library against purified polyclonal antibodies for negative and positive PCM sera caused by P. brasiliensis. The binding phages were sequenced and tested in a binding assay to evaluate its interaction with sera from normal individuals and PCM patients. Synthetic peptides derived from these phage clones were tested in a serological assay, and we observed a significant recognition of LP15 by sera from PCM patients infected with P. brasiliensis. Our results demonstrated that subtractive phage display selection may be useful for identifying new epitopes that can be applied to the serodiagnosis of PCM caused by P. brasiliensis. Letters in Applied Microbiology © 2017 The Society for Applied Microbiology.

  17. Hydrolytic enzymes in Paracoccidioides brasiliensis--ecological aspects.

    PubMed

    Benoliel, Bruno; Arraes, Fabrício B M; Reis, Viviane Castelo-Branco; Siqueira, Saulo J L de; Parachin, Nádia S; Torres, Fernando A G

    2005-06-30

    Paracoccidioides brasiliensis is a thermally dimorphic fungus that causes paracoccidioidomycosis. The yeast form of this pathogen is found in the animal host whereas the mycelial form is recovered from living and non-living organic material. The sole carbon source available in these habitats is represented by polysaccharides from the plant cell wall. Hydrolytic enzymes are necessary to convert these polymers into simple sugars for fungal metabolism. We report on the presence of ortholog genes of hydrolytic enzymes identified in the P. brasiliensis transcriptome and on hydrolytic activities in supernatants of induced P. brasiliensis cultures of mycelium and yeast cells. Enzymatic assays have shown cellulase and xylanase activities, both being higher in mycelium than in the yeast form. Amylase and chitinase activities were detected only in mycelium. Data so far reinforce the idea that mycelial P. brasiliensis is a saprobe.

  18. Cloning cattle.

    PubMed

    Oback, B; Wells, D N

    2003-01-01

    Over the past six years, hundreds of apparently normal calves have been cloned worldwide from bovine somatic donor cells. However, these surviving animals represent less than 5% of all cloned embryos transferred into recipient cows. Most of the remaining 95% die at various stages of development from a predictable pattern of placental and fetal abnormalities, collectively referred to as the "cloning-syndrome." The low efficiency seriously limits commercial applicability and ethical acceptance of somatic cloning and enforces the development of improved cloning methods. In this paper, we describe our current standard operating procedure (SOP) for cattle cloning using zona-free nuclear transfer. Following this SOP, the output of viable and healthy calves at weaning is about 9% of embryos transferred. Better standardization of cloning protocols across and within research groups is needed to separate technical from biological factors underlying low cloning efficiency.

  19. cDNA encoding a polypeptide including a hevein sequence

    DOEpatents

    Raikhel, N.V.; Broekaert, W.F.; Namhai Chua; Kush, A.

    1993-02-16

    A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1,018 nucleotides long and includes an open reading frame of 204 amino acids.

  20. Alternative to peat for Agaricus brasiliensis yield.

    PubMed

    Colauto, Nelson Barros; da Silveira, Adriano Reis; da Eira, Augusto Ferreira; Linde, Giani Andrea

    2010-01-01

    Casing layer is one of the most important components of Agaricus spp. production and it directly affects mushroom productivity, size and mass. The aim of this study was to evaluate potential raw materials as a casing layer and their effect on Agaricus brasiliensis productivity. Raw materials from Brazil with potential use were selected and characterized, and the most promising ones were tested as casing layers for mushroom yield. Evaluated raw materials included lime schist, vermiculite, eucalyptus sawdust, sand, São Paulo peat, Santa Catarina peat, subsoil and charcoal. Particle size, porosity and water absorption in relation to mushroom yield for casing layers were determined. Lime schist, an alternate casing layer to peat, is presented and the effects of the casing layer on the mushroom yield are discussed.

  1. [Microclimatic properties of the Triatoma brasiliensis habitat].

    PubMed

    Lorenzo, M G; Guarneri, A A; Pires, H H; Diotaiuti, L; Lazzari, C R

    2000-01-01

    Vector-borne transmission of Chagas disease in Northeast Brazil is basically by Triatoma brasiliensis. It is thus crucial to determine this species' microclimatic preferences as limiting factors for its distribution and ability to infest domestic environments. We analyze the microclimatic properties of the shelters in which these insects are found in wild, domestic, and peridomiciliary environments in the State of Ceará, at Brazil. We measure temperature and relative humidity (RH) every 15 minutes for 3 days. Thermal variation was greatly dampened inside both domiciliary refuges and the more protected internal places in wild stony sites. For RH, we observed a similar dampening pattern, but mean RH was lower in both domiciliary refuges and wild ones inside stony sites as compared to reference levels in the surrounding environment. The results are discussed with regard to this species' microclimatic preferences in the laboratory and its potential as determinants of its geographical distribution.

  2. [Cloning - controversies].

    PubMed

    Twardowski, T; Michalska, A

    2001-01-01

    Cloning of the human being is not only highly controversial; in the opinion of the authors it is impossible - we are not able to reproduce human behaviour and character traits. Reproduction through cloning is limited to personal genome resources. The more important is protection of genomic characteristics as private property and taking advantage of cloning for production of the human organs directly or through xenotransplants. In this paper we present the legislation related to cloning in Poland, in the European Union and other countries. We also indicate who and why is interested in cloning.

  3. A simple rectangular microstrip technique for determination of moisture content in Hevea rubber latex

    NASA Astrophysics Data System (ADS)

    Yahaya, Nor Zakiah; Abbas, Zulkifly; Norimi, Amizadillah Md; Yahaya, Muhamad Zamri; Razak, Nik Noor Ashikin Abd; Mustafa, Iskandar Shahrim

    2015-08-01

    A simple rectangular microstrip sensor for determination of moisture content in Hevea Rubber Latex is presented in this paper. The microstrip patch sensor was designed to operate at microwave frequency range from 1 to 5 GHz on a RT/Duroid substrate with 6.15 ±0.015 permittivity and 1.27 mm thickness. The width and length of the rectangular patch antenna was 18 mm and 38 mm, respectively. The reflection coefficient of the sensor loaded with Hevea latex at various percentages of moisture content from approximately 36.1% to 88.6 %. Calibration equations have been established between moisture content and phase of reflection coefficient at several selected frequencies. These equations were used to predict the amount of moisture content on Hevea latex based on the measured reflection coefficient values. The actual values of moisture content were obtained using standard oven drying method. The lowest mean relative error between actual and predicted moisture contents was 0.04 at 1 GHz.

  4. Human Cloning

    DTIC Science & Technology

    2006-07-20

    not believe that noncoital, asexual reproduction , such as cloning, would be considered a fundamental right by the Supreme Court. A ban on human...society by “crossing the boundary from sexual to asexual reproduction , thus approving in principle the genetic manipulation and control of nascent human... reproductive cloning and, by a vote of 10 to 7, a four-year moratorium on cloning for medical research purposes. The ethical issues surrounding reproductive

  5. Cryptic Chromosomal Diversity in the Complex "Geophagus" brasiliensis (Perciformes, Cichlidae).

    PubMed

    Oliveira, Isabel Araújo; Argolo, Leandro Araújo; Bitencourt, Jamille de Araújo; Diniz, Débora; Vicari, Marcelo Ricardo; Affonso, Paulo Roberto Antunes de Mello

    2016-02-01

    Among American cichlids, Geophagus stands out as a species-rich genus widespread over neotropical region. Despite their diversity and confusing taxonomy, only few and basic chromosomal reports are available in populations/species along Atlantic coast, hindering our understanding about evolutionary trends in this genus. Therefore, detailed chromosomal studies were performed in "Geophagus" brasiliensis complex from coastal rivers in northeastern Brazil, totalizing seven populations of Geophagus brasiliensis and one of Geophagus itapicuruensis. All samples shared a diploid number (2n) of 48 divided into 2 submetacentric and 46 subtelocentric/acrocentric chromosomes with (peri)centromeric heterochromatin, hypothesized as a symplesiomorphy for Geophagini. Although G. itapicuruensis and two populations of G. brasiliensis presented single NORs on short arms, multiple GC-rich rDNA sites were observed in the remaining G. brasiliensis samples, ranging from three to six NOR-bearing chromosomes. Inversely, 5S rDNA sites were invariably located at interstitial region on a st/a pair, nonsyntenic to NORs. A compilation of the data set in Geophagus shows that their chromosomal evolution has been driven by pericentric inversions and microstructural changes. Besides, the divergence found in northeastern Brazil places this region as a biodiversity hotspot. A taxonomic revision in the complex "Geophagus" brasiliensis is recommended with the support of cytogenetic analyses.

  6. Human neutrophils produce extracellular traps against Paracoccidioides brasiliensis.

    PubMed

    Mejía, Susana P; Cano, Luz E; López, Juan A; Hernandez, Orville; González, Ángel

    2015-05-01

    Neutrophils play an important role as effector cells and contribute to the resistance of the host against microbial pathogens. Neutrophils are able to produce extracellular traps (NETs) in response to medically important fungi, including Aspergillus spp., Candida albicans and Cryptococcus gattii. However, NET production in response to Paracoccidioides brasiliensis has yet to be studied. We have demonstrated that human neutrophils produce NETs against both conidia and yeasts of P. brasiliensis. Although the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI) did not alter NET production against conidia, it partially suppressed NET formation against P. brasiliensis yeasts. Cytochalasin D or IFN-γ did not affect the production of NETs against the fungus. Additionally, a mutant strain of P. brasiliensis with reduced expression of an alternative oxidase induced significantly higher levels of NETs in comparison with the WT strain. Finally, c.f.u. quantification of P. brasiliensis showed no significant differences when neutrophils were treated with DPI, DNase I or cytochalasin D as compared with untreated cells. These data establish that NET formation by human neutrophils appears to be either dependent or independent of reactive oxygen species production, correlating with the fungal morphotype used for stimulation. However, this mechanism was ineffective in killing the fungus.

  7. Academic Cloning.

    ERIC Educational Resources Information Center

    Sikula, John P.; Sikula, Andrew F.

    1980-01-01

    The authors define "cloning" as an integral feature of all educational systems, citing teaching practices which reward students for closely reproducing the teacher's thoughts and/or behaviors and administrative systems which tend to promote like-minded subordinates. They insist, however, that "academic cloning" is not a totally…

  8. Academic Cloning.

    ERIC Educational Resources Information Center

    Sikula, John P.; Sikula, Andrew F.

    1980-01-01

    The authors define "cloning" as an integral feature of all educational systems, citing teaching practices which reward students for closely reproducing the teacher's thoughts and/or behaviors and administrative systems which tend to promote like-minded subordinates. They insist, however, that "academic cloning" is not a totally…

  9. [Immunoglobulins in patients with Nocardia brasiliensis actinomycetoma].

    PubMed

    Méndez-Tovar, L J; Mondragón-González, R; Manzano-Gayosso, P; López-Martínez, R; Hernández-Hernández, F; Bonifaz, A; Anides Fonseca, A; Araiza, J; Vega-López, F

    2004-01-01

    Considering that some authors have reported an increasing of some immunoglobulins in actinomycetoma patients, in this study we propose to determine differential production of IgG1, IgG2, IgG3, IgG4 and IgGM in 25 patients with actinomycetoma and 25 healthy individuals from a mycetoma endemic area. Immunoglobulins were determined by ELISA technique. To sensibilize the plates, six Nocardia brasiliensis antigens were used: a crude antigen denominated NB and five derivatives (NB2, NB4, NB6, NB8 and NB10) obtained by their isoelectric point. Results showed that all IgG subclasses were higher in the patients' sera than in control sera, with a maximal difference to IgG3 and IgG4. To the latter subclass, six antigens were highly reactives. IgM levels were similar in both groups. As it occurs in other infections, in the actinomycetoma pathogenesis probably participate the increase or deficiency of a determined immunoglobulin class, as well as the relationship between different subclasses.

  10. Ultrastructure of Dimorphic Transformation in Paracoccidioides brasiliensis

    PubMed Central

    Carbonell, Luis M.

    1969-01-01

    The fine structure of Paracoccidioides brasiliensis undergoing temperature-dependent transformation from mycelium to yeast and vice versa (M ⇌ Y) was studied. The transitional form to mycelium from the yeast appears as an elongated bud that extends from the yeast and which has a mixture of characteristics from both the yeast and the mycelium. The transitional form to yeast from the mycelium starts with enlargement of the interseptal spaces and cracking of the outer electron-dense layer of the cell wall of the hypha. Later the interseptal spaces tend to become round and separate. In M → Y only few interseptal spaces seem to transform. The yeast is produced by self-transformation of the hypha. In Y → M a new structure is formed and the yeast dies. Intrahyphal hyphae are observed during the transformation from M → Y, and intrayeast hyphae during the Y → M. Due to the high mortality and breakage observed in both types of transformations, we believe that wound of the yeast or the mycelium could elicit this phenomenon. Images PMID:5359610

  11. Overview and perspectives the transcriptome of Paracoccidioides brasiliensis.

    PubMed

    Andrade, Rosângela V; Da Silva, Silvana P; Torres, Fernando A G; Poças-Fonseca, Marcio José; Silva-Pereira, Ildenete; Maranhão, Andrea Q; Campos, Elida G; Moraes, Lídia Maria P; Jesuíno, Rosália S A; Pereira, Maristela; Soares, Célia M A; Walter, Maria Emília M T; Carvalho, Maria Joseá A; Almeida, Nalvo F; Brigido, Marcelo M; Felipe, Maria Sueli S

    2005-12-01

    Paracoccidioides brasiliensis is a dimorphic and thermo-regulated fungus which is the causative agent of paracoccidioidomycosis, an endemic disease widespread in Latin America that affects 10 million individuals. Pathogenicity is assumed to be a consequence of the dimorphic transition from mycelium to yeast cells during human infection. This review shows the results of the P. brasiliensis transcriptome project which generated 6,022 assembled groups from mycelium and yeast phases. Computer analysis using the tools of bioinformatics revealed several aspects from the transcriptome of this pathogen such as: general and differential metabolism in mycelium and yeast cells; cell cycle, DNA replication, repair and recombination; RNA biogenesis apparatus; translation and protein fate machineries; cell wall; hydrolytic enzymes; proteases; GPI-anchored proteins; molecular chaperones; insights into drug resistance and transporters; oxidative stress response and virulence. The present analysis has provided a more comprehensive view of some specific features considered relevant for the understanding of basic and applied knowledge of P. brasiliensis.

  12. Characterization of the cellular antigens of Paracoccidioides brasiliensis yeast form.

    PubMed Central

    Casotto, M

    1990-01-01

    Antigenic components of the yeast extract of Paracoccidioides brasiliensis Linder 2511 cultured for 3, 8, 20, 30, and 60 days were examined by the Western blot (immunoblot) technique. The 3-day extract was chosen for characterization of the antigenic components because its stability did not vary with time and it contained all antigens identified by patient sera. Antibodies to cross-reacting antigens of P. brasiliensis extracts were detected in sera from patients with histoplasmosis, candidiasis, and aspergillosis. The 58-, 57-, 21-, and 16-kilodalton (kDa) antigens were specific for P. brasiliensis, while the 48- and 45-kDa antigens were specific for paracoccidioidomycosis. The Western blot technique is a useful tool for the diagnosis of disease and revealed heterogeneity in the responses of patient sera. The combination of the 58-, 57-, and 45-kDa proteins confirmed a diagnosis of paracoccidioidomycosis (87% of the cases). Images PMID:2380351

  13. Antineoplasic activity of Agaricus brasiliensis basidiocarps on different maturation phases

    PubMed Central

    Mourão, Francielly; Linde, Giani Andrea; Messa, Valdeci; da Cunha Júnior, Paulo Luiz; da Silva, Aristeu Vieira; da Eira, Augusto Ferreira; Colauto, Nelson Barros

    2009-01-01

    The fungus Agaricus brasiliensis is a Basidiomycete studied because of its immunomodulation and/or antitumor substances. The objective of this study was to verify the Agaricus brasiliensis antineoplasic activity in vivo on different basidiocarp maturation phases on Sarcoma 180 cells implanted in mice. Sarcoma cells were implanted in mice and after seven days mice were divided in three groups. The first group was treated with saline solution, the second group was treated with closed basidiocarp extract solution and the third group was treated with opened basidiocarp extract solution. After 30 days of being daily orally treated with these three solutions all animals suffered euthanasia, and the splenic index, tumor mass and volume were determined. No significant differences of the tumor growth inhibition in function of the different basidiocarp maturation phases for the Agaricus brasiliensis strain were observed. The in vivo basidiocarp antineoplasic average activity was 89.22%. PMID:24031439

  14. Alternative Oxidase Mediates Pathogen Resistance in Paracoccidioides brasiliensis Infection

    PubMed Central

    Hernández Ruiz, Orville; Gonzalez, Angel; Almeida, Agostinho J.; Tamayo, Diana; Garcia, Ana Maria; Restrepo, Angela; McEwen, Juan G.

    2011-01-01

    Background Paracoccidioides brasiliensis is a human thermal dimorphic pathogenic fungus. Survival of P. brasiliensis inside the host depends on the adaptation of this fungal pathogen to different conditions, namely oxidative stress imposed by immune cells. Aims and Methodology In this study, we evaluated the role of alternative oxidase (AOX), an enzyme involved in the intracellular redox balancing, during host-P. brasiliensis interaction. We generated a mitotically stable P. brasiliensis AOX (PbAOX) antisense RNA (aRNA) strain with a 70% reduction in gene expression. We evaluated the relevance of PbAOX during interaction of conidia and yeast cells with IFN-γ activated alveolar macrophages and in a mouse model of infection. Additionally, we determined the fungal cell's viability and PbAOX in the presence of H2O2. Results Interaction with IFN-γ activated alveolar macrophages induced higher levels of PbAOX gene expression in PbWt conidia than PbWt yeast cells. PbAOX-aRNA conidia and yeast cells had decreased viability after interaction with macrophages. Moreover, in a mouse model of infection, we showed that absence of wild-type levels of PbAOX in P. brasiliensis results in a reduced fungal burden in lungs at weeks 8 and 24 post-challenge and an increased survival rate. In the presence of H2O2, we observed that PbWt yeast cells increased PbAOX expression and presented a higher viability in comparison with PbAOX-aRNA yeast cells. Conclusions These data further support the hypothesis that PbAOX is important in the fungal defense against oxidative stress imposed by immune cells and is relevant in the virulence of P. brasiliensis. PMID:22039556

  15. Melatonin production in the sea star Echinaster brasiliensis (Echinodermata).

    PubMed

    Peres, Rafael; Amaral, Fernanda Gaspardo; Marques, Antonio Carlos; Neto, José Cipolla

    2014-04-01

    The primary hormone of the vertebrate pineal gland, melatonin, has been identified broadly throughout the tree of life, in animals, plants, and fungi, supporting a deep evolutionary origin for this signaling molecule. However, some key groups have not been studied. Echinoderms, deuterostome animals, are one of these groups. Herein we study the presence of melatonin and enzymes of its pathway in the sea star Echinaster brasiliensis. We demonstrate that E. brasiliensis produces endogenous melatonin, in the gonads, under a circadian pattern with a nocturnal peak of production. We also show that the enzymes arylalkylamine N-acetyltransferase (AANAT) and tryptophan hydroxylase (TPH) are present and are probably regulating the melatonin production.

  16. Larva of Palaemnema brasiliensis Machado (Odonata: Platystictidae), from Amazonas, Brazil.

    PubMed

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-02-09

    The larva of Palaemnema brasiliensis Machado, 2009 is described and illustrated based on last-instar larvae and exuviae of reared larvae collected in a blackwater stream in Barcelos and Presidente Figueiredo municipalities, Amazonas state, Brazil. The larva of P. brasiliensis can be distinguished from the two South American species of the genus with described larvae (P. clementia Selys and P. mutans Calvert), mainly by presence of a single obtuse cusp on the labial palp, the presence and configuration of setae in the caudal lamellae, and the proportional length of terminal filaments of the caudal lamellae. The family is recorded here for the first time in Brazilian state of Amazonas.

  17. Kalanchosine dimalate, an anti-inflammatory salt from Kalanchoe brasiliensis.

    PubMed

    Costa, Sônia Soares; de Souza, Maria de Lourdes Mendes; Ibrahim, Tereza; de Melo, Giany Oliveira; de Almeida, Ana Paula; Guette, Catherine; Férézou, Jean-Pierre; Koatz, Vera Lucia G

    2006-05-01

    This report describes the isolation and characterization of kalanchosine dimalate (KMC), an anti-inflammatory salt from the fresh juice of the aerial parts of Kalanchoe brasiliensis. KMC comprises the new metabolite kalanchosine (1) and malic acid (2) in a 1:2 stoichiometric ratio. Kalanchosine (1), 3,6-diamino-4,5-dihydroxyoctanedioic acid, is the first naturally occurring dimeric bis(gamma-hydroxy-beta-amino acid) and is at least partially responsible for the anti-inflammatory properties of K. brasiliensis.

  18. Overexpression of a Hevea brasiliensis ErbB-3 Binding protein 1 Gene Increases Drought Tolerance and Organ Size in Arabidopsis

    PubMed Central

    Cheng, Han; Chen, Xiang; Zhu, Jianshun; Huang, Huasun

    2016-01-01

    Rubber trees are economically important tropical tree species and the major source of natural rubber, which is an essential industrial material. This tropical perennial tree is susceptible to cold stress and other abiotic stresses, especially in the marginal northern tropics. Recent years, the genome sequencing and RNA-seq projects produced huge amount of sequence data, which greatly facilitated the functional genomics study. However, the characterization of individual functional gene is in urgent demands, especially for those involved in stress resistance. Here we identified and characterized the rubber tree gene ErbB-3 binding protein 1, which undergoes changes in expression in response to cold, drought stress and ABA treatment. HbEBP1 overexpression (OE) in Arabidopsis increased organ size, facilitated root growth and increased adult leaf number by delaying the vegetative-to-reproductive transition. In addition, HbEBP1 OE enhanced the resistance of the Arabidopsis plants to freezing and drought stress, demonstrating that this gene participates in the regulation of abiotic stress resistance. RD29a, RD22 and CYCD3;1 expression was also greatly enhanced by HbEBP1 OE, which explains its regulatory roles in organ size and stress resistance. The regulation of drought stress resistance is a novel function identified in plant EBP1 genes, which expands our understanding of the roles of EBP1 gene in response to the environment. Our results provide information that may lead to the use of HbEBP1 in genetically engineered crops to increase both biomass and abiotic stress resistance. PMID:27895658

  19. Allergenicity of Hev b 13, a major esterase allergen in natural rubber latex (Hevea brasiliensis) allergy, does not only depend on its carbohydrate moiety.

    PubMed

    Rougé, Pierre; Culerrier, Raphaël; Campistron, Marion; Granier, Claude; Bienvenu, Françoise; Bienvenu, Jacques; Didier, Alain; Barre, Annick

    2010-01-01

    The three-dimensional model built for the major latex allergen Hev b 13 consists of the typical organization of plant esterases made of a central bundle of five parallel beta-strands surrounded by five alpha-helices associated to two shorter alpha-helical segments. Up to 12 sets of sequential IgE-binding peptides were identified in SPOT experiments along the amino acid sequence of Hev b 13. They correspond in fact to eight IgE-binding epitopic stretches exposed on the surface of the allergen. With the exception of epitope #5, all other epitopes contain charged residues. Epitope #8 contains the 3rd putative N-glycosylation site of Hev b 13 and should consist of a glycotope, whereas all other identified IgE-binding areas occur outside the two remaining putative N-glycosylation sites. Accordingly, the allergenicity of Hev b 13 does not primarily depends on its carbohydrate moiety. Copyright 2010 Elsevier Ltd. All rights reserved.

  20. Effects of methanol-to-oil ratio, catalyst amount and reaction time on the FAME yield by in situ transesterification of rubber seeds (Hevea brasiliensis)

    NASA Astrophysics Data System (ADS)

    Abdulkadir, Bashir Abubakar; Uemura, Yoshimitsu; Ramli, Anita; Osman, Noridah B.; Kusakabe, Katsuki; Kai, Takami

    2014-10-01

    In this research, biodiesel is produced by in situ transesterification (direct transesterification) method from the rubber seeds using KOH as a catalyst. The influence of methanol to seeds mass ratio, duration of reaction, and catalyst loading was investigated. The result shows that, the best ratio of seeds to methanol is 1:6 (10 g seeds with 60 g methanol), 120 minutes reaction time and catalyst loading of 3.0 g. The maximum FAME yield obtain was 70 %. This findings support FAME production from the seeds of rubber tree using direct transesterifcation method from the seeds of rubber tree as an alternative to diesel fuel. Also, significant properties of biodiesel such as cloud point, density, pour point, specific gravity, and viscosity were investigated.

  1. Overexpression of a Hevea brasiliensis ErbB-3 Binding protein 1 Gene Increases Drought Tolerance and Organ Size in Arabidopsis.

    PubMed

    Cheng, Han; Chen, Xiang; Zhu, Jianshun; Huang, Huasun

    2016-01-01

    Rubber trees are economically important tropical tree species and the major source of natural rubber, which is an essential industrial material. This tropical perennial tree is susceptible to cold stress and other abiotic stresses, especially in the marginal northern tropics. Recent years, the genome sequencing and RNA-seq projects produced huge amount of sequence data, which greatly facilitated the functional genomics study. However, the characterization of individual functional gene is in urgent demands, especially for those involved in stress resistance. Here we identified and characterized the rubber tree gene ErbB-3 binding protein 1, which undergoes changes in expression in response to cold, drought stress and ABA treatment. HbEBP1 overexpression (OE) in Arabidopsis increased organ size, facilitated root growth and increased adult leaf number by delaying the vegetative-to-reproductive transition. In addition, HbEBP1 OE enhanced the resistance of the Arabidopsis plants to freezing and drought stress, demonstrating that this gene participates in the regulation of abiotic stress resistance. RD29a, RD22 and CYCD3;1 expression was also greatly enhanced by HbEBP1 OE, which explains its regulatory roles in organ size and stress resistance. The regulation of drought stress resistance is a novel function identified in plant EBP1 genes, which expands our understanding of the roles of EBP1 gene in response to the environment. Our results provide information that may lead to the use of HbEBP1 in genetically engineered crops to increase both biomass and abiotic stress resistance.

  2. Combined phylogenetic and morphometric information to delimit and unify the Triatoma brasiliensis species complex and the Brasiliensis subcomplex.

    PubMed

    Oliveira, Jader; Marcet, Paula L; Takiya, Daniela M; Mendonça, Vagner J; Belintani, Tiago; Bargues, Maria D; Mateo, Lucia; Chagas, Vivian; Folly-Ramos, Elaine; Cordeiro-Estrela, Pedro; Gurgel-Gonçalves, Rodrigo; Costa, Jane; da Rosa, João A; Almeida, Carlos E

    2017-02-20

    "Triatoma brasiliensis species complex" was defined as a monophyletic group of the species: T. brasiliensis, T. juazeirensis, T. melanica, and T. sherlocki. An alternative grouping scheme proposed the concept of "Brasiliensis subcomplex" which included the former species together with T. melanocephala, T. petrocchiae, T. lenti, T. tibiamaculata, and T. vitticeps. To evaluate the relationship among these taxa we combined the results obtained with four mitochondrial genes (12S, 16S, COI and Cytb, adding to 1811bp) and geometric morphometric analysis of wings and heads. Panstrongylus megistus was included in the analysis as it was previously found related to T. tibiamaculata, T. melanocephala and T. vitticeps. The results of both molecular and morphometric approaches clearly grouped the species analyzed into two monophyletic units, supported by both genetic and wing variability. The first one (G1) comprises the four species originally included in the T. brasiliensis species complex plus T. lenti and T. petrocchiae. The second group (G2) was composed by T. melanocephala, T. tibiamaculata and T. vitticeps, and remarkably, P. megistus if considering wing variability and phylogenetic results. Nevertheless, geometric morphometrics of heads provided a quantitative measurement that discriminates Panstrongylus from the Triatoma species based on the position of the antennal insertion relative to eyes, as it is used as the generic distinctive character. The discrepancy among approaches questions the validity of this character to define Panstrongylus genus. Independently of the chosen group definition -"T. brasiliensis species complex" or "Brasiliensis subcomplex"-we propose to delimit it to species of G1 that are all associated with the Caatinga biome in the Brazilian Northeast. G2 are the ones associated with the Atlantic Forest biome.

  3. Why Clone?

    MedlinePlus

    ... disease. Find out more about Stem Cells . Reviving Endangered or Extinct Species You might have seen the Jurassic Park movies. ... related goat species to make a male. Cloning endangered species is much easier, mainly because the surviving animals ...

  4. Rabies in the insectivorous bat Tadarida brasiliensis in southeastern Brazil.

    PubMed

    Uieda, W

    1998-10-01

    This is the first recorded case of rabies in the insectivorous bat Tadarida brasiliensis in the State of S. Paulo, Southeastern Brazil. The infected bat was found in the afternoon while hanging on the internal wall of an urban building. This observation reinforces the notion as to the caution one must exercise regarding bats found in unusual situations.

  5. 5-Lipoxygenase Activity Increases Susceptibility to Experimental Paracoccidioides brasiliensis Infection

    PubMed Central

    Tristão, Fabrine Sales Massafera; Rocha, Fernanda Agostini; Moreira, Ana Paula; Cunha, Fernando Queiroz; Rossi, Marcos Antonio

    2013-01-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the thermodimorphic fungus Paracoccidioides brasiliensis. Leukotrienes and lipoxins are lipid mediators produced after 5-lipoxygenase (5-LO) activation that exhibit pro- and anti-inflammatory roles, respectively. Here, we have investigated the contribution of 5-LO enzymatic activity in PCM using an experimental model of P. brasiliensis infection. B6.129 wild-type (B6.129) and 5-LO-deficient (5-LO−/−) mice were intravenously inoculated with a virulent strain of P. brasiliensis (Pb18), and the survival rate of the infected mice was investigated on different days after yeast infection. 5-LO−/− mice exhibited an increased survival rate associated with a decreased number of CFU. The resistance of 5-LO−/− during PCM was associated with augmented nitric oxide (NO) production and the formation of compact granulomas. In addition, the absence of 5-LO was associated with a diminished number of CD4+ CD25+ regulatory T cells, higher levels of gamma interferon and interleukin-12, and increased T-bet (a T-box transcription factor that directs Th1 lineage commitment) mRNA levels in the lungs. Taken together, our results show for the first time that 5-LO enzymatic activity increases susceptibility to P. brasiliensis, suggesting that this pathway may be a potential target for therapeutic intervention during PCM. PMID:23381993

  6. Nocardia brasiliensis: from microbe to human and experimental infections.

    PubMed

    Salinas-Carmona, M C

    2000-09-01

    Nocardia brasiliensis is a Gram-positive bacterium that lives as a saprophyte in soil. In this article the physical properties, chemical composition and taxonomic position of this species is reviewed. Human infections and an experimental model of actinomycetoma in BALB/c mice as well as the host-immune response is described.

  7. Temporal Dynamics of Reproduction in Hemiramphus brasiliensis (Osteichthyes: Hemiramphidae)

    PubMed Central

    de Oliveira, Mônica Rocha

    2014-01-01

    The reproductive aspects of Hemiramphus brasiliensis were analyzed with a view to verify the temporal dynamics of reproduction. This paper presents data on sex ratio, length at first sexual maturity, macroscopic and histological aspects of gonad development, gonadosomatic index (GSI), reproductive period, and fecundity of H. brasiliensis. The fishes were captured from the coastal waters of Rio Grande do Norte, northeastern Brazil. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8 cm and that of females was 21.5 cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads of H. brasiliensis showed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species was 1153 (±258.22) mature oocytes for 50 g body weight of female. The microscopic characteristics of gonad development indicate that H. brasiliensis is a multiple spawner, presenting a prolonged reproductive period during the whole year, with a peak in the month of April, and is considered as an opportunistic strategist. PMID:25512946

  8. Redescription of Tenuipalpus heveae Baker (Acari: Tenuipalpidae) and description of a new species collected on rubber tree from Amazonia, Brazil

    USDA-ARS?s Scientific Manuscript database

    Tenuipalpus heveae Baker, 1945 was described based only from female specimens collected on rubber trees from Belterra, State of Pará, Brazil. However, the original description does not provide essential information, and thus, it may be difficult to correctly identify the species. In this paper, we r...

  9. Recombinant Paracoccin Reproduces the Biological Properties of the Native Protein and Induces Protective Th1 Immunity against Paracoccidioides brasiliensis Infection

    PubMed Central

    Alegre, Ana Claudia Paiva; Oliveira, Aline Ferreira; Dos Reis Almeida, Fausto Bruno; Roque-Barreira, Maria Cristina; Hanna, Ebert Seixas

    2014-01-01

    Background Paracoccin is a dual-function protein of the yeast Paracoccidioides brasiliensis that has lectin properties and N-acetylglucosaminidase activities. Proteomic analysis of a paracoccin preparation from P. brasiliensis revealed that the sequence matched that of the hypothetical protein encoded by PADG-3347 of isolate Pb-18, with a polypeptide sequence similar to the family 18 endochitinases. These endochitinases are multi-functional proteins, with distinct lectin and enzymatic domains. Methodology/principal findings The multi-exon assembly and the largest exon of the predicted ORF (PADG-3347), was cloned and expressed in Escherichia coli cells, and the features of the recombinant proteins were compared to those of the native paracoccin. The multi-exon protein was also used for protection assays in a mouse model of paracoccidioidomycosis. Conclusions/Significance Our results showed that the recombinant protein reproduced the biological properties described for the native protein—including binding to laminin in a manner that is dependent on carbohydrate recognition—showed N-acetylglucosaminidase activity, and stimulated murine peritoneal macrophages to produce high levels of TNF-α and nitric oxide. Considering the immunomodulatory potential of glycan-binding proteins, we also investigated whether prophylactic administration of recombinant paracoccin affected the course of experimental paracoccidioidomycosis in mice. In comparison to animals injected with vehicle (controls), mice treated with recombinant paracoccin displayed lower pulmonary fungal burdens and reduced pulmonary granulomas. These protective effects were associated with augmented pulmonary levels of IL-12 and IFN-γ. We also observed that injection of paracoccin three days before challenge was the most efficient administration protocol, as the induced Th1 immunity was balanced by high levels of pulmonary IL-10, which may prevent the tissue damage caused by exacerbated inflammation. The

  10. Molecular cloning.

    PubMed

    Lessard, Juliane C

    2013-01-01

    This protocol describes the basic steps involved in conventional plasmid-based cloning. The goals are to insert a DNA fragment of interest into a receiving vector plasmid, transform the plasmid into E. coli, recover the plasmid DNA, and check for correct insertion events.

  11. Functional genome of the human pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Felipe, Maria Sueli S; Torres, Fernando A G; Maranhão, Andrea Q; Silva-Pereira, Ildinete; Poças-Fonseca, Marcio J; Campos, Elida G; Moraes, Lídia M P; Arraes, Fabrício B M; Carvalho, Maria José A; Andrade, Rosângela V; Nicola, André M; Teixeira, Marcus M; Jesuíno, Rosália S A; Pereira, Maristela; Soares, Célia M A; Brígido, Marcelo M

    2005-09-01

    Paracoccidioides brasiliensis is a dimorphic and thermo-regulated fungus which is the causative agent of paracoccidioidomycosis, an endemic disease widespread in Latin America. Pathogenicity is assumed to be a consequence of the cellular differentiation process that this fungus undergoes from mycelium to yeast cells during human infection. In an effort to elucidate the molecular mechanisms involved in this process a network of Brazilian laboratories carried out a transcriptome project for both cell types. This review focuses on the data analysis yielding a comprehensive view of the fungal metabolism and the molecular adaptations during dimorphism in P. brasiliensis from analysis of 6022 groups, related to expressed genes, which were generated from both mycelium and yeast phases.

  12. General metabolism of the dimorphic and pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Arraes, Fabrício B M; Benoliel, Bruno; Burtet, Rafael T; Costa, Patrícia L N; Galdino, Alexandro S; Lima, Luanne H A; Marinho-Silva, Camila; Oliveira-Pereira, Luciana; Pfrimer, Pollyanna; Procópio-Silva, Luciano; Reis, Viviane Castelo-Branco; Felipe, Maria Sueli S

    2005-06-30

    Annotation of the transcriptome of the dimorphic fungus Paracoccidioides brasiliensis has set the grounds for a global understanding of its metabolism in both mycelium and yeast forms. This fungus is able to use the main carbohydrate sources, including starch, and it can store reduced carbons in the form of glycogen and trehalose; these provide energy reserves that are relevant for metabolic adaptation, protection against stress and infectivity mechanisms. The glyoxylate cycle, which is also involved in pathogenicity, is present in this fungus. Classical pathways of lipid biosynthesis and degradation, including those of ketone body and sterol production, are well represented in the database of P. brasiliensis. It is able to synthesize de novo all nucleotides and amino acids, with the sole exception of asparagine, which was confirmed by the fungus growth in minimal medium. Sulfur metabolism, as well as the accessory synthetic pathways of vitamins and co-factors, are likely to exist in this fungus.

  13. Paracoccidioides brasiliensis AND Paracoccidioides lutzii, A SECRET LOVE AFFAIR

    PubMed Central

    ARANTES, Thales Domingos; BAGAGLI, Eduardo; NIÑO-VEGA, Gustavo; SAN-BLAS, Gioconda; THEODORO, Raquel Cordeiro

    2015-01-01

    SUMMARY To commemorate Prof. Carlos da Silva Lacaz's centennial anniversary, the authors have written a brief account of a few, out of hundreds, biological, ecological, molecular and phylogenetic studies that led to the arrival of Paracoccidioides lutzii, hidden for more than a century within Paracoccidioides brasiliensis. Lacaz's permanent interest in this fungus, and particularly his conviction on the benefits that research on paracoccidioidomycosis would bring to patients, were pivotal in the development of the field. PMID:26465366

  14. Partial purification of protective antigens from Nippostrongylus brasiliensis in mice.

    PubMed

    Rhalem, A; Bourdieu, C; Luffau, G; Pery, P

    1988-01-01

    The purification of antigens from Nippostrongylus brasiliensis, through their ability to provoke cellular proliferation of immune cells and through their recognition by antibodies, led to an antigenic preparation which was extracted from adult worms and which contained only two proteins (MW 14 and 43 Kd). Mice which were vaccinated by the oral route after the entrapment of these two proteins in liposomes were strongly protected.

  15. Anti-inflammatory and antinociceptive effects of Garcinia brasiliensis.

    PubMed

    Santa-Cecília, Flávia V; Vilela, Fabiana C; da Rocha, Cláudia Q; Dias, Danielle F; Cavalcante, Gustavo P; Freitas, Lissara A S; dos Santos, Marcelo H; Giusti-Paiva, Alexandre

    2011-01-27

    In Brazilian folk medicine, the leaves of Garcinia brasiliensis are used to treat tumors, inflammation of the urinary tract and arthritis as well as to relieve pain. Nevertheless, scientific information regarding Garcinia brasiliensis is limited; there are no reports related to its possible anti-inflammatory and antinociceptive effects. This study employed in vivo inflammatory and nociceptive models to evaluate the scientific basis for the traditional use of Garcinia brasiliensis. Carrageenan-induced paw edema, peritonitis and fibrovascular tissue growth induced by s.c. cotton pellet implantation were used to investigate the anti-inflammatory activity of Garcinia brasiliensis ethanolic extract (GbEE) in rats. Formalin and acetic acid-induced writhing tests were used to investigate the antinociceptive activity in mice. GbEE at test doses of 30-300 mg/kg p.o. clearly demonstrated anti-inflammatory effects by reduced paw edema induced by carrageenan, inhibited leukocyte recruitment into the peritoneal cavity, and in the model of chronic inflammation using the cotton pellet-induced fibrovascular tissue growth in rats, the GbEE significantly inhibited the formation of granulomatous tissue. The extracts at test doses of 30-300 mg/kg, p.o., clearly demonstrated antinociceptive activity, except for the first phase of the formalin test. GbEE markedly demonstrated anti-inflammatory action in rats and antinociceptive activity in mice, which supports previous claims of the traditional use of species of the Garcinia genus for inflammation and pain. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  16. Matrix metalloproteinases with gelatinolytic activity induced by Paracoccidioides brasiliensis infection

    PubMed Central

    Nishikaku, Angela Satie; Ribeiro, Luciana Cristina; Molina, Raphael Fagnani Sanchez; Albe, Bernardo Paulo; Cunha, Cláudia da Silva; Burger, Eva

    2009-01-01

    Matrix metalloproteinases (MMPs) modulate extracellular matrix turnover, inflammation and immunity. We studied MMP-9 and MMP-2 in experimental paracoccidioidomycosis. At 15 and 120 days after infection (DAI) with virulent Paracoccidioides brasiliensis, MMP-9 was positive by immunohistochemistry in multinucleated giant cells, in mononuclear cells with macrophage and lymphocyte morphologies and also in fungal cells in the lesions of susceptible and resistant mice. Using gelatin zymography, pro- and active MMP-9 and active MMP-2 were detected in all infected mice, but not in controls. Gelatinolytic activity was not observed in P. brasiliensis extracts. Semiquantitative analysis of gelatinolytic activities revealed weak or absent MMP-2 and strong MMP-9 activity in both mouse strains at 15 DAI, declining at 120 DAI. Avirulent P. brasiliensis-infected mice had residual lesions with MMP-9-positive pseudoxantomatous macrophages, but no gelatinase activity at 120 DAI. Our findings demonstrate the induction of MMPs, particularly MMP-9, in experimental paracoccidioidomycosis, suggesting a possible influence in the pattern of granulomas and in fungal dissemination. PMID:19765107

  17. Paracoccidioides brasiliensis isolated from armadillos is virulent to Syrian hamsters.

    PubMed

    Peraçoli, M T; Sugizaki, M F; Mendes, R P; Naiff, R; Montenegro, M R

    1999-12-01

    Isolates of Paracoccidioides brasiliensis may vary in virulence according to time of in vitro subcultivation. The present study compared the morphology and pathogenicity to hamsters of two P. brasiliensis isolates: one obtained from human lesions and maintained in the laboratory for several years (Pb-18) and the other isolate recovered from hamsters inoculated with organ homogenates from armadillos (Pb-T). The microscopic morphology of Pb-18 and Pb-T showed yeast cells with similar diameter. However, Pb-T produced a significantly higher number of buds per mother cell than Pb-18. Besides, the mycelial form of Pb-T developed abundant sporulation during 8 weeks of culture which was absent in the Pb-18 isolate. Virulence studies demonstrated that mortality rates, antibody levels, fungal load and extent of lesions in the organs were significantly higher in animals infected with Pb-T. The results demonstrated that Pb-T recently isolated from an animal was more virulent than Pb-18. These differences between the two P. brasiliensis isolates may be indicators of virulence attenuation in this fungal species.

  18. Heterologous expression and characterization of processing α-glucosidase I from Aspergillus brasiliensis ATCC 9642.

    PubMed

    Miyazaki, Takatsugu; Matsumoto, Yuji; Matsuda, Kana; Kurakata, Yuma; Matsuo, Ichiro; Ito, Yukishige; Nishikawa, Atsushi; Tonozuka, Takashi

    2011-12-01

    A gene for processing α-glucosidase I from a filamentous fungus, Aspergillus brasiliensis (formerly called Aspergillus niger) ATCC 9642 was cloned and fused to a glutathione S-transferase tag. The active construct with the highest production level was a truncation mutant deleting the first 16 residues of the hydrophobic N-terminal domain. This fusion enzyme hydrolyzed pyridylaminated (PA-) oligosaccharides Glc(3)Man(9)GlcNAc(2)-PA and Glc(3)Man(4)-PA and the products were identified as Glc(2)Man(9)GlcNAc(2)-PA and Glc(2)Man(4)-PA, respectively. Saturation curves were obtained for both Glc(3)Man(9)GlcNAc(2)-PA and Glc(3)Man(4)-PA, and the K (m) values for both substrates were estimated in the micromolar range. When 1 μM Glc(3)Man(4)-PA was used as a substrate, the inhibitors kojibiose and 1-deoxynojirimycin had similar effects on the enzyme; at 20 μM concentration, both inhibitors reduced activity by 50%.

  19. Hevea latex lectin binding protein in C-serum as an anti-latex coagulating factor and its role in a proposed new model for latex coagulation.

    PubMed

    Wititsuwannakul, Rapepun; Pasitkul, Piyaporn; Jewtragoon, Pattavuth; Wititsuwannakul, Dhirayos

    2008-02-01

    A distinct protein specifically recognized by its strong interaction with Hevea latex lectin (HLL) was detected in the aqueous C-serum fraction of centrifuged fresh latex. This C-serum lectin binding protein (CS-HLLBP) exhibited strong inhibition of HLL-induced hemagglutination. The CS-HLLBP was purified to homogeneity by a protocol that included ammonium sulfate fractionation, size exclusion and ion exchange chromatography. The purified CS-HLLBP had a specific HI titer of 0.23microg ml(-1). Its M(r)s analyzed by SDS-PAGE was ca. 40kDa and that by gel filtration was ca. 204kDa. It has a pI value of 4.7, an optimum activity between pH 6 and10 and was heat stable up to 50 degrees C. The HI activity of CS-HLLBP was abolished upon treatment with chitinase. The CS-HLLBP inhibited HLL-induced rubber particle aggregation in a dose dependent manner. A highly positive correlation between CS-HLLBP activity and rubber yield per tapping was found. The correlations for fresh latex (r=0.98, P<0.01) and dry rubber (r=0.95, P<0.01) were both highly significant. This indicated that the CS-HLLBP might be used as a reliable marker for the mass screening of young seedlings to identify and select clones with potential to be superior producers of rubber. A latex anti-coagulating role of the CS-HLLBP is proposed. The findings described in this 3 paper series have been used to propose a new model of rubber latex coagulation that logically describes roles for the newly characterized latex lectin and the two lectin binding proteins.

  20. Intracellular multiplication of Paracoccidioides brasiliensis in macrophages: killing and restriction of multiplication by activated macrophages.

    PubMed Central

    Brummer, E; Hanson, L H; Restrepo, A; Stevens, D A

    1989-01-01

    The effect of coculturing yeast-form Paracoccidioides brasiliensis with murine cells was studied. Coculture of resident peritoneal or pulmonary macrophages with P. brasiliensis for 72 h dramatically enhanced fungal multiplication 19.3 +/- 2.4- and 4.7 +/- 0.8-fold, respectively, compared with cocultures with lymph node cells or complete tissue culture medium alone. Support of P. brasiliensis multiplication by resident peritoneal macrophages was macrophage dose dependent. Lysates of macrophages, supernatants from macrophage cultures, or McVeigh-Morton broth, like complete tissue culture medium, did not support multiplication of P. brasiliensis in 72-h cultures. Time course microscopic studies of cocultures in slide wells showed that macrophages ingested P. brasiliensis cells and that the ingested cells multiplied intracellularly. In sharp contrast to resident macrophages, lymphokine-activated peritoneal and pulmonary macrophages not only prevented multiplication but reduced inoculum CFU by 96 and 100%, respectively, in 72 h. Microscopic studies confirmed killing and digestion of P. brasiliensis ingested by activated macrophages in 48 h. These findings indicate that resident macrophages are permissive for intracellular multiplication of P. brasiliensis and that this could be a factor in pathogenicity. By contrast, activated macrophages are fungicidal for P. brasiliensis. Images PMID:2744848

  1. Interaction between Paracoccidioides brasiliensis conidia and the coagulation system: involvement of fibrinogen

    PubMed Central

    Tamayo, Diana; Hernández, Orville; Muñoz-Cadavid, Cesar; Cano, Luz Elena; González, Angel

    2013-01-01

    The infectious process starts with an initial contact between pathogen and host. We have previously demonstrated that Paracoccidioides brasiliensis conidia interact with plasma proteins including fibrinogen, which is considered the major component of the coagulation system. In this study, we evaluated the in vitro capacity of P. brasiliensis conidia to aggregate with plasma proteins and compounds involved in the coagulation system. We assessed the aggregation of P. brasiliensis conidia after incubation with human serum or plasma in the presence or absence of anticoagulants, extracellular matrix (ECM) proteins, metabolic and protein inhibitors, monosaccharides and other compounds. Additionally, prothrombin and partial thromboplastin times were determined after the interaction of P. brasiliensis conidia with human plasma. ECM proteins, monosaccharides and human plasma significantly induced P. brasiliensis conidial aggregation; however, anticoagulants and metabolic and protein inhibitors diminished the aggregation process. The extrinsic coagulation pathway was not affected by the interaction between P. brasiliensis conidia and plasma proteins, while the intrinsic pathway was markedly altered. These results indicate that P. brasiliensis conidia interact with proteins involved in the coagulation system. This interaction may play an important role in the initial inflammatory response, as well as fungal disease progression caused by P. brasiliensis dissemination. PMID:23827999

  2. Interaction between Paracoccidioides brasiliensis conidia and the coagulation system: involvement of fibrinogen.

    PubMed

    Tamayo, Diana; Hernández, Orville; Muñoz-Cadavid, Cesar; Cano, Luz Elena; González, Angel

    2013-06-01

    The infectious process starts with an initial contact between pathogen and host. We have previously demonstrated that Paracoccidioides brasiliensis conidia interact with plasma proteins including fibrinogen, which is considered the major component of the coagulation system. In this study, we evaluated the in vitro capacity of P. brasiliensis conidia to aggregate with plasma proteins and compounds involved in the coagulation system. We assessed the aggregation of P. brasiliensis conidia after incubation with human serum or plasma in the presence or absence of anticoagulants, extracellular matrix (ECM) proteins, metabolic and protein inhibitors, monosaccharides and other compounds. Additionally, prothrombin and partial thromboplastin times were determined after the interaction of P. brasiliensis conidia with human plasma. ECM proteins, monosaccharides and human plasma significantly induced P. brasiliensis conidial aggregation; however, anticoagulants and metabolic and protein inhibitors diminished the aggregation process. The extrinsic coagulation pathway was not affected by the interaction between P. brasiliensis conidia and plasma proteins, while the intrinsic pathway was markedly altered. These results indicate that P. brasiliensis conidia interact with proteins involved in the coagulation system. This interaction may play an important role in the initial inflammatory response, as well as fungal disease progression caused by P. brasiliensis dissemination.

  3. Molecular Characterization of Nippostrongylus brasiliensis (Nematoda: Heligmosomatidae) from Mus musculus in India

    PubMed Central

    Chaudhary, Anshu; Goswami, Urvashi; Singh, Hridaya Shanker

    2016-01-01

    Mus musculus (Rodentia: Muridae) has generally been infected with a rodent hookworm Nippostrongylus brasiliensis. In this report, we present morphological and molecular identification of N. brasiliensis by light and scanning electron microscopy and PCR amplification of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene and the protein sequences encoded by cox1 gene, respectively. Despite the use of N. brasiliensis in many biochemistry studies from India, their taxonomic identification was not fully understood, especially at the species level, and no molecular data is available in GenBank from India. Sequence analysis of cox1 gene in this study revealed that the present specimen showed close identity with the same species available in GenBank, confirming that the species is N. brasiliensis. This study represents the first record of molecular identification of N. brasiliensis from India and the protein structure to better understand the comparative phylogenetic characteristics. PMID:28095659

  4. Interaction between Linepithema micans (Hymenoptera: Formicidae) and Eurhizococcus brasiliensis (Hemiptera: Margarodidae) in vineyards.

    PubMed

    Nondillo, Aline; Sganzerla, Vânia Maria Ambrosi; Bueno, Odair Correa; Botton, Marcos

    2013-06-01

    Eurhizococcus brasiliensis (Wille) (Hemiptera: Margarodidae) is a soil scale that is considered the main pest of vineyards in Brazil. The ant Linepithema micans (Forel) (Hymenoptera: Formicidae) is frequently found associated with this species of scale in infested areas. The effect of the presence of L. micans on the infestation and dispersal capacity of E. brasiliensis on vine roots was measured in a greenhouse, using Paulsen 1103 rootstock seedlings planted in simple and double "Gallotti Cages." Treatments measured were: infestation of roots with E. brasiliensis or L. micans, and infestation with both species together. In the experiment using simple Gallotti Cages, with E. brasiliensis associated with L. micans, higher mean numbers of cysts and ants per plant were recorded, a result significantly different from that found for infestation with scale only. When double Gallotti Cages were used, first-instar nymphs were transported between the cages. The results showed that L. micans transports and aids in the attachment of E. brasiliensis to vine plants.

  5. The kex2 gene from the dimorphic and human pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Venancio, Emerson J; Daher, Bruno S; Andrade, Rosângela V; Soares, Célia M A; Pereira, Ildinete Silva; Felipe, Maria Sueli S

    2002-10-01

    Kexin-like protein is a component of the subtilase family of proteinases involved in the processing of proproteins to their active forms. Kexin-like proteins are also synthesized as a propeptide and this is involved in (auto)inhibition, correct folding and subcellular sorting of proteins. The kexin-like protein was described as the product of the kex2 gene for Aspergillus niger, Candida albicans, Saccharomyces cerevisiae, Yarrowia lipolytica and other fungi. Disruption of the kex2 gene in C. albicans and Y. lipolytica affects hyphae production and induces morphological cell defects, strongly suggesting a possible role of kexin-like proteins in dimorphism of human pathogenic fungi. In this work, we report the nucleotide sequence of the kex2 gene cloned from the dimorphic and human pathogenic fungus Paracoccidioides brasiliensis (Pbkex2). An open reading frame (ORF) of 2622 bp was identified in the complete sequence, interrupted by only one intron of 93 bp. The 5' non-coding region contains consensus sequences such as canonical TATA, CAAT boxes and putative motifs for transcriptional factors binding sites, such as HSE-like regulating genes involved in thermo-dependent processes; Xbp1, reported as a transcriptional factor that may control genes involved in cell morphology; and StuAp, which may regulate spore differentiation and pseudohyphal growth in fungi. In the 3' non-coding region were observed the canonical motifs necessary for correct mRNA processing and polyadenylation. The deduced protein sequence consists of 842 amino acid residues, showing identity to kexin-like proteinases from A. niger (55%), Emericella nidulans (53%) and C. albicans (48%). Comparative sequence analysis of P. brasiliensis kexin-like protein reveals the presence of homologous regions related to a signal peptide, a propeptide, a subtilisin-like catalytic domain, a P domain, a S/T rich region and a transmembrane domain. A putative Golgi retrieval signal (YEFEMI) has also been found in the

  6. Revalidation and redescription of Triatoma brasiliensis macromelasoma Galvão, 1956 and an identification key for the Triatoma brasiliensis complex (Hemiptera: Reduviidae: Triatominae)

    PubMed Central

    Costa, Jane; Correia, Nathália Cordeiro; Neiva, Vanessa Lima; Gonçalves, Teresa Cristina Monte; Felix, Márcio

    2013-01-01

    Triatoma brasiliensis macromelasoma is revalidated based on the results of previous multidisciplinary studies on the Triatoma brasiliensis complex, consisting of crossing experiments and morphological, biological, ecological and molecular analyses. These taxonomic tools showed the closest relationship between T. b. macromelasoma and Triatoma brasiliensis brasiliensis. T. b. macromelasoma is redescribed based on specimens collected in the type locality and specimens from a F1 colony. The complex now comprises T. b. brasiliensis, T. b. macromelasoma, Triatoma melanica, Triatoma juazeirensis and Triatoma sherlocki. An identification key for all members of the complex is presented. This detailed comparative study of the morphological features of T. b. macromelasoma and the remaining members of the complex corroborates results from multidisciplinary analyses, suggesting that the subspecific status is applicable. This subspecies can be distinguished by the following combination of features: a pronotum with 1+1 narrow brownish-yellow stripes on the submedian carinae, not attaining its apex, hemelytra with membrane cells darkened on the central portion and legs with an incomplete brownish-yellow ring on the apical half of the femora. Because the T. brasiliensis complex is of distinct epidemiological importance throughout its geographic distribution, a precise identification of its five members is important for monitoring and controlling actions against Chagas disease transmission. PMID:24037202

  7. [Eugenics and human cloning].

    PubMed

    Boloz, W

    2001-01-01

    Because of legislative bans there are still no reports of human cloning. However eager public debate is currently running, concerning medical, legal, social and ethical aspects of human cloning. Arguments for and against human cloning are presented. An important argument against cloning is the danger of eugenic tendencies connected with cloning, which could lead to genetic discrimination.

  8. A Paracoccidioides brasiliensis glycan shares serologic and functional properties with cryptococcal glucuronoxylomannan.

    PubMed

    Albuquerque, Priscila C; Cordero, Radames J B; Fonseca, Fernanda L; Peres da Silva, Roberta; Ramos, Caroline L; Miranda, Kildare R; Casadevall, Arturo; Puccia, Rosana; Nosanchuk, Joshua D; Nimrichter, Leonardo; Guimaraes, Allan J; Rodrigues, Marcio L

    2012-11-01

    The cell wall of the yeast form of the dimorphic fungus Paracoccidioides brasiliensis is enriched with α1,3-glucans. In Cryptococcus neoformans, α1,3-glucans interact with glucuronoxylomannan (GXM), a heteropolysaccharide that is essential for fungal virulence. In this study, we investigated the occurrence of P. brasiliensis glycans sharing properties with cryptococcal GXM. Protein database searches in P. brasiliensis revealed the presence of sequences homologous to those coding for enzymes involved in the synthesis of GXM and capsular architecture in C. neoformans. In addition, monoclonal antibodies (mAbs) raised to cryptococcal GXM bound to P. brasiliensis cells. Using protocols that were previously established for extraction and analysis of C. neoformans GXM, we recovered a P. brasiliensis glycan fraction composed of mannose and galactose, in addition to small amounts of glucose, xylose and rhamnose. In comparison with the C. neoformans GXM, the P. brasiliensis glycan fraction components had smaller molecular dimensions. The P. brasiliensis components, nevertheless, reacted with different GXM-binding mAbs. Extracellular vesicle fractions of P. brasiliensis also reacted with a GXM-binding mAb, suggesting that the polysaccharide-like molecule is exported to the extracellular space in secretory vesicles. An acapsular mutant of C. neoformans incorporated molecules from the P. brasiliensis extract onto the cell wall, resulting in the formation of surface networks that resembled the cryptococcal capsule. Coating the C. neoformans acapsular mutant with the P. brasiliensis glycan fraction resulted in protection against phagocytosis by murine macrophages. These results suggest that P. brasiliensis and C. neoformans share metabolic pathways required for the synthesis of similar polysaccharides and that P. brasiliensis yeast cell walls have molecules that mimic certain aspects of C. neoformans GXM. These findings are important because they provide additional evidence for

  9. Differential gene expression analysis of Paracoccidioides brasiliensis during keratinocyte infection.

    PubMed

    Peres da Silva, Roberta; Matsumoto, Marcelo Teruyuki; Braz, Jaqueline Derissi; Voltan, Aline Raquel; de Oliveira, Haroldo Cesar; Soares, Christiane Pienna; Mendes Giannini, Maria José Soares

    2011-03-01

    Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis, one of the most important systemic fungal diseases in Latin America. This initiates in lung tissue and can subsequently disseminate to other tissues. Clinical manifestations range from localized forms to disseminated disease that can progress to lethality, probably depending on the relationships among the virulence of the fungus, the immune response and the ability to interact with the surface structures and invade epithelial cells and mononuclear cells of the host. It is generally regarded as a multifocal disease, with oral lesions as the prominent feature. The aim of this study was to evaluate P. brasiliensis yeast infection in normal oral keratinocytes (NOKs). The differential expression of mRNAs and proteins was also determined when the fungus was placed in contact with the cell in order to characterize differentially expressed genes and proteins during P. brasiliensis infection. After contact with NOKs, the fungus appeared to induce alterations in the cells, which showed cellular extensions and cavitations, probably resulting from changes in the actin cytoskeleton seen at 5 and 8 h after infection. Levels of protein expression were higher after reisolation of the fungus from infected NOK culture compared with culture of the fungus in medium. The analysis identified transcripts related to 19 proteins involved in different biological processes. Transcripts were found with multiple functions including induction of cytokines, protein metabolism, alternative carbon metabolism, zinc transport and the stress response during contact with NOKs. The proteins found suggested that the yeast was in a stress situation, as indicated by the presence of RDS1. Nevertheless, the yeast seemed to be proliferating and metabolically active, as shown by the presence of a proteasome, short-chain acetylator, glucosamine-6-phosphate isomerase and ADP/ATP carrier transcripts. Additionally, metabolic pathways may

  10. Immunomodulatory effect of diethylcarbamazine in mice infected with Nocardia brasiliensis.

    PubMed

    García-Hernández, M; Castro-Corona, M A; Segoviano-Ramírez, J C; Brattig, N W; Medina-De la Garza, C E

    2014-11-01

    We tested whether diethylcarbamazine (DEC) or ivermectin (IVM), both antiparasitic drugs with reported immunomodulatory properties, were able to affect the immune system to potentiate host defense mechanisms and protect against actinomycetoma in a mouse model. Male BALB/c mice of 10-12 weeks of age were injected with either Nocardia brasiliensis or saline solution. Recorded were the effects of a treatment by DEC (6 mg/kg per os daily for one week) or IVM (200 μg/kg subcutaneously on days 1 and 3) on (i) the development of mycetoma lesion, (ii) the expression of reactive oxygen intermediates (ROI) by phagocytes, (iii) the proliferation index of lymphocytes and (iv) antibody production of IgG and IgM. After an initial lesion in all mice, DEC inhibited a full development and progression of actinomycetoma resulting in a reduced lesion size (p < 0.001). IVM had no inhibitory effect on the development of mycetoma. Furthermore, DEC treatment was associated with a significant enhancement of ROI expression (p < 0.05) by polymorphonuclear neutrophils at day 3 after infection. Lymphocyte proliferation in response to N. brasiliensis antigens and concanavalin A in DEC-treated group was higher than in non-treated group at day 21 and 28 postinfection (p < 0.01). Significant changes in antibody response were not observed. By all parameters tested, DEC was superior to IVM regarding immunostimulatory potency. In conclusion, DEC expressed an in vivo influence on the immune status during the infection by N. brasiliensis leading to retrogression of the mycetoma and increasing cellular immune responses. Our findings may indicate a potential use of DEC as a putative adjuvant in infectious disease or vaccination.

  11. In vitro susceptibility testing of Paracoccidioides brasiliensis to sulfonamides.

    PubMed Central

    Restrepo, A; Arango, M D

    1980-01-01

    A total of 60 clinical isolates of Paracoccidioides brasiliensis were tested for susceptibility to sulfadiazine and sulfadimethoxyne by the agar dilution technique. A modification of the Mueller-Hinton medium was devised which gave good growth of the yeast form. The minimum inhibitory concentrations for only 51.6% of the isolates were in the range of the recommended blood serum concentration (50 micrograms/ml). For 6 to 8% of the isolates, the minimum inhibitory concentrations were above 200 micrograms of both sulfadiazine and sulfadimethoxyne per ml. A significant decreases in susceptibility was demonstrated for one isolate obtained from a patient relapsing during sulfonamide therapy. Images PMID:7416744

  12. Ammonia utilization by the bruchid beetle,Caryedes brasiliensis [Bruchidae].

    PubMed

    Rosenthal, G A; Janzen, D H

    1985-04-01

    The seed predator,Caryedes brasiliensis [Bruchidae] generates appreciable ammonia in its dietary use and detoxification ofL-canavanine and its catabolic product,L-canaline.L-Canavanine is a toxic allelochemical ofDioclea megacarpa seeds, the food of the developing larvae. Bruchid beetle larvae rely upon glutamic acid dehydrogenase and glutamine synthetase to use ammonia for glutamic acid synthesis from 2-oxoglutaric acid and conversion of the former to glutamine. These reactions provide the larvae with a means for metabolically eliminating ammonia. Proline serves as a carbon skeleton source for glutamic acid formation.

  13. The anti-inflammatory effect of Agaricus brasiliensis is partly due to its linoleic acid content.

    PubMed

    Saiki, Papawee; Kawano, Yasuhiro; Van Griensven, Leo J L D; Miyazaki, Koyomi

    2017-10-12

    For hundreds of years mushrooms have been used as functional food for health. The basidiomycete Agaricus brasiliensis (A. brasiliensis) is famous for the medicinal properties of its beta glucans and of its antioxidants. Most researchers have studied polysaccharides from A. brasiliensis for their anti-inflammatory activity. However, active compounds from this mushroom have not yet been studied for the inactivation of NO inhibitory activity. The present study aimed to find the active compounds from A. brasiliensis for their NO inhibitory activity related inflammatory activity. This study found that linoleic acid isolated from A. brasiliensis inhibited NO production and suppressed the expression of pro-inflammatory cytokines including TNF-α, IL-6, IL-1β, and NOS2 in RAW 264.7 cells. Linoleic acid also suppressed the expression of NF-κB subunit p50 and restored PPARα. This leads to the conclusion that linoleic acid from A. brasiliensis could reduce NO production and inflammatory activity in RAW 264.7 cells by the inhibition of p50 and via the activation of PPARα. This study suggests that linoleic acid present in A. brasiliensis could play a role in the prevention of inflammatory diseases for which this edible mushroom is already known.

  14. Extracellular vesicles from Paracoccidioides brasiliensis induced M1 polarization in vitro

    PubMed Central

    da Silva, Thiago Aparecido; Roque-Barreira, Maria Cristina; Casadevall, Arturo; Almeida, Fausto

    2016-01-01

    Extracellular vesicles (EVs) released by eukaryotes, archaea, and bacteria contain proteins, lipids, polysaccharides, and other molecules. The cargo analysis of EVs shows that they contain virulence factors suggesting a role in the pathogenesis of infection. The proteome, lipidome, RNA content, and carbohydrate composition of EVs from Paracoccidioides brasiliensis and Paracoccidioides lutzii were characterized. However, the effects of P. brasiliensis EVs on the host immune system have not yet been investigated. Herein, we verified that EVs from P. brasiliensis induce the production of proinflammatory mediators by murine macrophages in a dose-dependent manner. Addition of EV to macrophages also promoted transcription of the M1-polarization marker iNOs and diminish that of the M2 markers Arginase-1, Ym-1, and FIZZ-1. Furthermore, the augmented expression of M2-polarization markers, stimulated by IL-4 plus IL-10, was reverted toward an M1 phenotype in response to secondary stimulation with EVs from P. brasiliensis. The ability of EVs from P. brasiliensis to promote M1 polarization macrophages favoring an enhanced fungicidal activity, demonstrated by the decreased CFU recovery of internalized yeasts, with comparable phagocytic efficacy. Our results suggest that EVs from P. brasiliensis can modulate the innate immune response and affect the relationship between P. brasiliensis and host immune cells. PMID:27775058

  15. Taxonomic and Functional Microbial Signatures of the Endemic Marine Sponge Arenosclera brasiliensis

    PubMed Central

    Trindade-Silva, Amaro E.; Rua, Cintia; Silva, Genivaldo G. Z.; Dutilh, Bas E.; Moreira, Ana Paula B.; Edwards, Robert A.; Hajdu, Eduardo; Lobo-Hajdu, Gisele; Vasconcelos, Ana Tereza; Berlinck, Roberto G. S.; Thompson, Fabiano L.

    2012-01-01

    The endemic marine sponge Arenosclera brasiliensis (Porifera, Demospongiae, Haplosclerida) is a known source of secondary metabolites such as arenosclerins A-C. In the present study, we established the composition of the A. brasiliensis microbiome and the metabolic pathways associated with this community. We used 454 shotgun pyrosequencing to generate approximately 640,000 high-quality sponge-derived sequences (∼150 Mb). Clustering analysis including sponge, seawater and twenty-three other metagenomes derived from marine animal microbiomes shows that A. brasiliensis contains a specific microbiome. Fourteen bacterial phyla (including Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Cloroflexi) were consistently found in the A. brasiliensis metagenomes. The A. brasiliensis microbiome is enriched for Betaproteobacteria (e.g., Burkholderia) and Gammaproteobacteria (e.g., Pseudomonas and Alteromonas) compared with the surrounding planktonic microbial communities. Functional analysis based on Rapid Annotation using Subsystem Technology (RAST) indicated that the A. brasiliensis microbiome is enriched for sequences associated with membrane transport and one-carbon metabolism. In addition, there was an overrepresentation of sequences associated with aerobic and anaerobic metabolism as well as the synthesis and degradation of secondary metabolites. This study represents the first analysis of sponge-associated microbial communities via shotgun pyrosequencing, a strategy commonly applied in similar analyses in other marine invertebrate hosts, such as corals and algae. We demonstrate that A. brasiliensis has a unique microbiome that is distinct from that of the surrounding planktonic microbes and from other marine organisms, indicating a species-specific microbiome. PMID:22768320

  16. Expression of alpha tubulin during the dimorphic transition of Paracoccidioides brasiliensis.

    PubMed

    Silva, W P; Soares, R B; Jesuino, R S; Izacc, S M; Felipe, M S; Soares, C M

    2001-10-01

    In this study we analyzed the expression of (alpha-tubulin during the dimorphic transition of the human-pathogenic fungus Paracoccidioides brasiliensis. The alpha-tubulin from P. brasiliensis was recognized by a commercially available anti-tubulin antibody and was developmentally regulated during the dimorphic form transition. We detected at least two alpha-tubulin isoforms in the mycelial state and only one isoform in the yeast forms. This finding suggests specific roles for the alpha-tubulin isoforms in P. brasiliensis's yeast and mycelial forms.

  17. Virulence attenuation and phenotypic variation of Paracoccidioides brasiliensis isolates obtained from armadillos and patients.

    PubMed

    Macoris, S A G; Sugizaki, M F; Peraçoli, M T S; Bosco, S M G; Hebeler-Barbosa, F; Simões, L B; Theodoro, R C; Trinca, L A; Bagagli, E

    2006-05-01

    Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, the most important systemic mycosis in Latin America. The virulence profiles of five isolates of P. brasiliensis were studied in two different moments and correlated with some colonial phenotypic aspects. We observed a significant decrease in the virulence and an intense phenotypic variation in the mycelial colony. The recognition of all ranges of phenotypic and virulence variation of P. brasiliensis, as well as its physiological and genetic basis, will be important for a better comprehension of its pathogenic and epidemiological features.

  18. A critical analysis of isolation of Paracoccidioides brasiliensis from soil.

    PubMed

    Franco, M; Bagagli, E; Scapolio, S; da Silva Lacaz, C

    2000-06-01

    The present review is a critical analysis of positive and negative reports of the isolation of Paracoccidioides brasiliensis from soil. The strains isolated from soil or soil-contaminated material (dogfood, penguin feces) by Batista et al. in Recife, Brazil, Negroni in the Argentinian Chaco, Albornoz in rural Venezuela, Silva-Vergara et al. in Ibiá, Brazil, Ferreira et al. in Uberlândia, Brazil, and Gezuele et al. at the Uruguayan base in the Antarctic region, presented mycological characteristics consistent with P. brasiliensis. In most of these studies, morphological characterization was complemented with an evaluation of virulence and antigenicity, and biochemical or molecular analysis. These isolations, therefore, can be considered true, supporting the concept of soil as an important element in the ecology of the pathogen. The large number of negative reports in attempts involving soil samples and the low repeatability of isolation of the fungus from the same area indicate that the specific conditions supporting growth of the pathogen in soil have not been fully clarified.

  19. Susceptibility and resistance of inbred mice to Paracoccidioides brasiliensis.

    PubMed Central

    Calich, V. L.; Singer-Vermes, L. M.; Siqueira, A. M.; Burger, E.

    1985-01-01

    Nine different inbred strains of mice inoculated intraperitoneally with yeast cells of Paracoccidioides brasiliensis showed significantly varying patterns of susceptibility. The A/SN strain was found to be the most resistant, while BIOD2/nSn, BIO.A and BIOD2/oSn the most susceptible strains. These susceptibility differences were not dependent on the size of challenge inocula and sex of animals. All strains studied showed a mean survival time proportional to the size of inocula used. Although almost all infected male mice presented a shorter survival time when compared with females, significant mortality differences between sexes were found only in two of the strains studied, namely BALB/c and BIOD2/nSn. The H-2 region did not influence the susceptibility pattern since the A/SN and BIO.A strains share the same H-2 haplotype and were respectively highly resistant and susceptible to P. brasiliensis. Furthermore, the presence of C5 and unresponsiveness to lipopolysaccharide had no influence on the mortality data observed. Specific antibodies were detected only in a small number of animals and titres were consistently low, appearing later in the resistant (A/SN) than in a susceptible strain (BIO.A). Omentum, spleen and liver were the most affected organs in both strains, but the susceptible mice had more granulomatous lesions and earlier dissemination of the fungus. PMID:4063162

  20. On classical cloning and no-cloning

    NASA Astrophysics Data System (ADS)

    Teh, Nicholas J.

    2012-02-01

    It is part of information theory folklore that, while quantum theory prohibits the generic (or universal) cloning of states, such cloning is allowed by classical information theory. Indeed, many take the phenomenon of no-cloning to be one of the features that distinguishes quantum mechanics from classical mechanics. In this paper, we argue that pace conventional wisdom, in the case where one does not include a machine system, there is an analog of the no-cloning theorem for classical systems. However, upon adjoining a non-trivial machine system (or ancilla) one finds that, pace the quantum case, the obstruction to cloning disappears for pure states. We begin by discussing some conceptual points and category-theoretic generalities having to do with cloning, and proceed to discuss no-cloning in both the case of (non-statistical) classical mechanics and classical statistical mechanics.

  1. A role for a Hevea latex lectin-like protein in mediating rubber particle aggregation and latex coagulation.

    PubMed

    Wititsuwannakul, Rapepun; Pasitkul, Piyaporn; Kanokwiroon, Kamonwan; Wititsuwannakul, Dhirayos

    2008-01-01

    An in vitro aggregation of washed lutoid membrane and rubber particles, respectively, prepared from the bottom (lutoid) fraction and rubber layer of centrifuged fresh latex, leading to the formation of rubber coagulum necessary for a latex coagulation was demonstrated. A Triton X-100 extract of washed lutoid membrane proteins, isolated and prepared from the bottom fraction of centrifuged fresh latex was examined for its role in the latex coagulation process. It induced agglutination of rabbit erythrocytes, indicating the presence of a lectin-like protein. Hevea latex lectin-like protein (HLL) was purified to homogeneity by active chitin binding separation, followed by DEAE-Sepharose chromatography. Its M(r) analyzed by SDS-PAGE was 17 kDa, whereas that determined by gel filtration was 267 kDa. The HLL had a pI value of 7.2. Several glycoproteins were shown to inhibit the HLL-induced hemagglutination. The hemagglutinin activity of HLL was enhanced by Ca(2+). Of most interest was the finding that HLL strongly induced aggregation of the Hevea latex rubber particles (RP). This strong RP aggregation leads to latex coagulation, indicating the possibility that it is involved in the formation of the coagulum that plugs the latex vessel ends and stops the flow of latex upon tapping. In addition, the purified HLL also induced aggregation of RP taken from several other non-Hevea latex producing plants. This might indicate either a common or universal role of this lectin-like protein in RP aggregation and hence latex coagulation. This paper, for the first time, provides clear and unequivocal evidence for either a key biological role or physiological function of an endogenous latex lectin-like protein in the sequential process of latex coagulation.

  2. A novel and enantioselective epoxide hydrolase from Aspergillus brasiliensis CCT 1435: purification and characterization.

    PubMed

    Beloti, Lilian L; Costa, Bruna Z; Toledo, Marcelo A S; Santos, Clelton A; Crucello, Aline; Fávaro, Marianna T P; Santiago, André S; Mendes, Juliano S; Marsaioli, Anita J; Souza, Anete P

    2013-10-01

    A novel epoxide hydrolase from Aspergillus brasiliensis CCT1435 (AbEH) was cloned and overexpressed in Escherichia coli cells with a 6xHis-tag and purified by nickel affinity chromatography. Gel filtration analysis and circular dichroism measurements indicated that this novel AbEH is a homodimer in aqueous solution and contains the typical secondary structure of an α/β hydrolase fold. The activity of AbEH was initially assessed using the fluorogenic probe O-(3,4-epoxybutyl) umbelliferone and was active in a broad range of pH (6-9) and temperature (25-45°C); showing optimum performance at pH 6.0 and 30°C. The Michaelis constant (KM) and maximum rate (Vmax) values were 495μM and 0.24μM/s, respectively. Racemic styrene oxide (SO) was used as a substrate to assess the AbEH activity and enantioselectivity, and 66% of the SO was hydrolyzed after only 5min of reaction, with the remaining (S)-SO ee exceeding 99% in a typical kinetic resolution behavior. The AbEH-catalyzed hydrolysis of SO was also evaluated in a biphasic system of water:isooctane; (R)-diol in 84% ee and unreacted (S)-SO in 36% ee were produced, with 43% conversion in 24h, indicating a discrete enantioconvergent behavior for AbEH. This novel epoxide hydrolase has biotechnological potential for the preparation of enantiopure epoxides or vicinal diols.

  3. The Clone Factory

    ERIC Educational Resources Information Center

    Stoddard, Beryl

    2005-01-01

    Have humans been cloned? Is it possible? Immediate interest is sparked when students are asked these questions. In response to their curiosity, the clone factory activity was developed to help them understand the process of cloning. In this activity, students reenact the cloning process, in a very simplified simulation. After completing the…

  4. The Clone Factory

    ERIC Educational Resources Information Center

    Stoddard, Beryl

    2005-01-01

    Have humans been cloned? Is it possible? Immediate interest is sparked when students are asked these questions. In response to their curiosity, the clone factory activity was developed to help them understand the process of cloning. In this activity, students reenact the cloning process, in a very simplified simulation. After completing the…

  5. Isolation and characterization of microsatellite markers in the Serra Spanish mackerel, Scomberomorus brasiliensis

    USDA-ARS?s Scientific Manuscript database

    Thirteen nuclear-encoded microsatellites from a genomic DNA library of Serra Spanish mackerel, Scomberomorus brasiliensis, were isolated and characterized. The microsatellites include 10 perfect repeats (8 tetranucleotide and 2 dinucleotide) and 3 imperfect repeats (2 tetranucleotide and 1 dinucleo...

  6. Identification of thermostable beta-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger.

    PubMed

    Pedersen, Mads; Lauritzen, Henrik Klitgaard; Frisvad, Jens Christian; Meyer, Anne S

    2007-05-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta-xylosidases. The beta-xylosidase activities of the A. brasiliensis and A. niger strains had similar temperature and pH optima at 75 degrees C and pH 5 and retained 62% and 99%, respectively, of these activities over 1 h at 60 degrees C. At 75 degrees C, these values were 38 and 44%, respectively. Whereas A. niger is a well known enzyme producer, this is the first report of xylanase and thermostable beta-xylosidase production from the newly identified, non-ochratoxin-producing species A. brasiliensis.

  7. New records of pyrrolizidine alkaloid-feeding insects. Hemiptera and Coleoptera on Senecio brasiliensis.

    PubMed

    Klitzke; Trigo

    2000-04-01

    New records are reported for a Hemipteran (Largus rufipennis) and a Coleopteran (Chauliognathus fallax) feeding on Senecio brasiliensis (Asteraceae) and sequestering pyrrolizidine alkaloids (PAs). Both insects are warningly colored and rejected by predators.

  8. Agaricus brasiliensis (sun mushroom) affects the expression of genes related to cholesterol homeostasis.

    PubMed

    de Miranda, Aline Mayrink; Rossoni Júnior, Joamyr Victor; Souza E Silva, Lorena; Dos Santos, Rinaldo Cardoso; Silva, Marcelo Eustáquio; Pedrosa, Maria Lúcia

    2017-06-01

    The sun mushroom (Agaricus brasiliensis) is considered a major source of bioactive compounds with potential health benefits. Mushrooms typically act as lipid-lowering agents; however, little is known about the mechanisms of action of A. brasiliensis in biological systems. This study aimed to determine the underlying mechanism involved in the cholesterol-lowering effect of A. brasiliensis through the assessment of fecal and serum lipid profiles in addition to gene expression analysis of specific transcription factors, enzymes, and transporters involved in cholesterol homeostasis. Twenty-four albino Fischer rats approximately 90 days old, with an average weight of 205 g, were divided into four groups of 6 each and fed a standard AIN-93 M diet (C), hypercholesterolemic diet (H), hypercholesterolemic diet +1 % A. brasiliensis (HAb), or hypercholesterolemic diet +0.008 % simvastatin (HS) for 6 weeks. Simvastatin was used as a positive control, as it is a typical drug prescribed for lipid disorders. Subsequently, blood, liver, and feces samples were collected for lipid profile and quantitative real-time polymerase chain reaction gene expression analyses. Diet supplementation with A. brasiliensis significantly improved serum lipid profiles, comparable to the effect observed for simvastatin. In addition, A. brasiliensis dietary supplementation markedly promoted fecal cholesterol excretion. Increased expression of 7α-hydroxylase (CYP7A1), ATP-binding cassette subfamily G-transporters (ABCG5/G8), and low-density lipoprotein receptor (LDLR) was observed following A. brasiliensis administration. Our results suggest that consumption of A. brasiliensis improves the serum lipid profile in hypercholesterolemic rats by modulating the expression of key genes involved in hepatic cholesterol metabolism.

  9. In vitro effects of natural killer cells against Paracoccidioides brasiliensis yeast phase.

    PubMed Central

    Jimenez, B E; Murphy, J W

    1984-01-01

    Recently, data have been reported suggesting natural killer (NK) cells may function in natural resistance against a fungus, Cryptococcus neoformans. The primary objective of this study was to examine the reactivity of murine splenic cells against another fungus, Paracoccidioides brasiliensis. Levels of NK activity in effector cell pools were varied by: (i) removing nylon wool-adherent cells, (ii) fractionating splenic cells on Percoll discontinuous gradients, (iii) using old and young effector cell donor mice, (iv) using donors from different strains, and (v) pretreating donors with NK-augmenting and -depressing agents. The various effector cell pools were simultaneously used in the 4-h 51Cr release assay with YAC-1 targets to determine the NK reactivity and in the in vitro growth inhibition assay against P. brasiliensis yeast phase targets. In each case, the level of NK reactivity correlated with the ability of the effector cells to inhibit the in vitro growth of P. brasiliensis. NK activity and P. brasiliensis growth-inhibiting ability could be augmented by fractionation of splenic cells through nylon wool or Percoll gradients. The effector cells responsible for the NK activity and P. brasiliensis growth inhibition were characterized as being nylon wool nonadherent, being found in the low-density fractions from Percoll discontinuous gradients, and having no detectable Thy-1 antigen or immunoglobulin but having asialo GM1 on their surface. These data support the contention that NK or NK-like cells are responsible for limiting the in vitro growth of P. brasiliensis. PMID:6500701

  10. Inhibition of human neutrophil apoptosis by Paracoccidioides brasiliensis: role of interleukin-8.

    PubMed

    Acorci, M J; Dias-Melicio, L A; Golim, M A; Bordon-Graciani, A P; Peraçoli, M T S; Soares, A M V C

    2009-02-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis caused by Paracoccidiodes brasiliensis that presents a wide spectrum of clinical manifestations. Because of the great number of neutrophils polymorphonuclear neutrophils (PMN) found in the P. brasiliensis granuloma, studies have been done to evaluate the role of these cells during the development of the infection. This fungus is found intracellularly in PMN and monocytes/macrophages, suggesting that it is capable of evading damage and surviving inside these cells. Thus, in the present study, we investigated whether P. brasiliensis can prolong the lifetime of PMN, and if this process would be related with IL-8 levels. PMN apoptosis and intracellular levels of IL-8 were analysed by flow cytometry and culture supernatants IL-8 levels were evaluated by enzyme-linked immunosorbent assay. We found that coincubation with P. brasiliensis yeast cells results in an inhibition of PMN apoptosis, which was associated with increase in IL-8 production by these cells. Cocultures treatment with monoclonal antibody anti-IL-8 reversed the inhibitory effect of P. brasiliensis on PMN apoptosis, besides to increase spontaneous apoptosis of these cells. These data show that, in contrast to other microbial pathogens that drive phagocytes into apoptosis to escape killing, P. brasiliensis can extend the lifetime of normal human PMN by inducing autocrine IL-8 production.

  11. Actinomycetoma by Nocardia brasiliensis in a girl with Down syndrome.

    PubMed

    Pardo, Martha; Bonifaz, Alexandro; Valencia, Adriana; Araiza, Javier; Mejia, Silvia Anett; Mena-Cedillos, Carlos

    2008-08-15

    We describe the case of a 14-year-old girl with Down syndrome and a large cutaneous plaque localized to the right neck and shoulder that had enlarged over five years after a minor traumatic injury. The plaque was characterized by numerous inflammatory nodules and fistulae that secreted purulent discharge. Nocardia grains were identified and Nocardia brasiliensis was identified by culture. Histopathology examination showed a chronic inflammatory infiltrate with granuloma development. The treatment scheme was with Diaminodiphenylsulfone 50/mg/d and Trimethoprim-Sulfamethoxazole 800/160 mg BID. Therapy was continued over 1(1/2) years, with a tapering dose. After 2(1/2) years of continuous treatment, clinical and microbiological healing was achieved.

  12. [Isolation of an Paracoccidioides brasiliensis exoantigen from solid culture media].

    PubMed

    Gago, J; Godio, C; Ochoa, L; Negroni, R; Nejamkis, M R

    1995-01-01

    The goal of this work was to develop in solid medium a fast method to obtain Paracoccidioides brasiliensis (Pb) with a high yield. Four culture media were assayed: Sabouraud honey-agar, Sabouraud dextrose-agar, tomato -agar-medium (TOM) and a medium based on grape pulp. The most exhuberant growth was observed in medium based on grape pulp. Antigen was prepared in microscale at 6, 10 and 15 days incubation of solid cultures and the crude product concentrated by means of Centriplus tubes (Helena, France). Isolated antigens were subjected to polyacrylamide gel electrophoresis, followed by immunolabelling and detection of the characteristic gp45 antigen employing human and Pb-infected rat sera. Best results were observed after 10 days culture in grape medium. None of the other three media afforded comparable results.

  13. Involvement of Hevea latex organelle membrane proteins in the rubber biosynthesis activity and regulatory function.

    PubMed

    Wititsuwaannakul, Dhirayos; Rattanapittayaporn, Atiya; Koyama, Tanetoshi; Wititsuwaannakul, Rapepun

    2004-03-15

    Centrifugation of fresh Hevea rubber latex yields three distinct fractions. The sediment bottom fraction (BF) content of membrane-bound organelles is ca. 20 vol.-% of latex. Prolonged storage or delayed use of fresh latex will result in disintegration and loss of the bottom fraction. This is due to the osmotically sensitive BF rupture and its membrane debris being tightly bound to the top rubber particles (RP) phase. The BF membrane was found to be highly active for rubber biosynthesis (RB), in contrast to previous reports that describe RB only occurring on the RP surface. It was clearly shown that washed BF membrane (WBM) was much more active than fresh RP for RB activity. WBM was highly activated by SDS for RB in a biphasic manner, but SDS strongly inhibited the RP. Probably WBM micelle formation resulted in a highly increased active surface area for RB. C55-PP (UPP) was a very active allylic for WBM in RB function, but inactive for RP. Serial acetone extraction of WBM proteins showed a distinct profile of the fractions with different RB activity. WBM isolated proteins suspended in 2% sodium dodecyl sulfate (SDS) with an RB activity equal to that of intact WBM was with the 20% acetone protein fraction. The 60 and 80% fractions were inactive. Combining the 20 with 80% fractions showed a complete inhibition of RB activity. Complete RB loss was also found when WBM was mixed with the 80% fraction, indicating that WBM has both an enzyme system and a factor for regulation of the RB activity in a well controlled metabolic function for the latex RB process.

  14. Significant role of bacterial undecaprenyl diphosphate (C55-UPP) for rubber synthesis by Hevea latex enzymes.

    PubMed

    Rattanapittayaporn, Atiya; Wititsuwannakul, Dhirayos; Wititsuwannakul, Rapepun

    2004-11-20

    Washed bottom fraction (BF) membrane-bound particles of centrifuged fresh Hevea latex were found to be very active in rubber biosynthesis (RB). The washed BF membrane (WBM) showed higher RB activity and is strongly stimulated by anionic surfactants--more by DOC than SDS. WBM enzymes system can synthesize rubber either with allylic isoprenes (higher RB) or without (lower RB). Washed rubber particles (WRP), used generally in RB assays, had very low RB activity compared to the much higher activity observed for WBM. Bacterial undecaprenyl diphoshate (C(55)-UPP) was very active allylic initiator for rubber synthesis by WBM. Comparisons of allylic UPP with the shorter ones (C(15)-FPP, C(20)-GGPP) showed that UPP was the most effective. WBM activity orders were UPP > GGPP > FPP. The DOC activated WBM synthesized less polyprenyl intermediates (butanol extractable) but more final rubber product (toluene/hexane extract), different than FPP and GGPP. WBM enzymes were highly versatile in using diverse different allylics, but UPP was most preferable. WRP was found a little active for UPP with DOC, but still much lower than WBM. Rubber product analysis by RP-TLC with acetone/hexane solvent system showed that WBM was mostly rubber, but WRP was mainly the intermediates. Quantitative analysis showed that WBM labeled rubber was confined to the origin spot, different than WRP as mainly labeled intermediates. It was thus confirmed that the WBM plays the key role in RB functions, and not WRP as mostly reported. WBM served as the actual rubber synthesis site, and bacterial UPP was very good RB initiator.

  15. Experimental model of arthritis induced by Paracoccidioides brasiliensis in rats.

    PubMed

    Loth, Eduardo Alexandre; Biazin, Samia Khalil; Paula, Claudete Rodrigues; Simão, Rita de Cássia Garcia; de Franco, Marcello Fabiano; Puccia, Rosana; Gandra, Rinaldo Ferreira

    2012-09-01

    Paracoccidioidomycosis (PCM), a disease caused by the fungus Paracoccidioides brasiliensis (Pb), is highly prevalent in Brazil, where it is the principal cause of death by systemic mycoses. The disease primarily affects men aged 30-50 year old and usually starts as a pulmonary focus and then may spread to other organs and systems, including the joints. The present study aimed to develop an experimental model of paracoccidioidomycotic arthritis. Two-month-old male Wistar rats (n = 48) were used, divided in 6 groups: test groups EG/15 and EG/45 (received one dose of 100 μl of saline containing 10(5) Pb viable yeasts in the knee); heat killed Pb-group HK/15 and HK/45 (received a suspension of 10(5) Pb nonviable yeasts in the knee) and control groups CG/15 and CG/45 (received only sterile saline in the knee). The rats were killed 15 and 45 days postinoculation. In contrast with the control rats, the histopathology of the joints of rats of the test groups (EG/15 and EG/45) revealed a picture of well-established PCM arthritis characterized by extensive sclerosing granulomatous inflammation with numerous multiple budding fungal cells. The X-ray examination revealed joint alterations in these groups. Only metabolic active fungi evoked inflammation. The experimental model was able to induce fungal arthritis in the knees of the rats infected with metabolic active P. brasiliensis. The disease tended to be regressive and restrained by the immune system. No evidence of fungal dissemination to the lungs was observed.

  16. Immunochemistry of the Group-Specific Polysaccharide of Nocardia brasiliensis

    PubMed Central

    Estrada-Parra, Sergio; Zamora, Abel; Bojalil, L. F.

    1965-01-01

    Estrada-Parra, Sergio (Escuela Nacional de Ciencias Biológicas, México, D.F., México), Abel Zamora, and L. F. Bojalil. Immunochemistry of the group-specific polysaccharide of Nocardia brasiliensis. J. Bacteriol. 90:571–574. 1965.—The group-specific polysaccharide of Nocardia brasiliensis was further purified, yielding an amorphous white material with the following characteristics: [α]D20 = + 48; nitrogen, 0.5%; phosphorus, 0.1%; and ash as sodium, 0.8%. The polymer is made of d-arabinose and d-galactose in a molar ratio of 3:1, and no other sugars were detected. Mild hydrolysis liberates mainly arabinose. The polysaccharide consumes 3.46 μmoles of periodate per mg of polymer in 15 days at 4 C (this value remains constant after 4 more days). Oxidation results in destruction of two of the arabinose, with the formation of two glycerols after borohydride reduction and hydrolysis. The polysaccharide oxidized by periodate and reduced under mild acid hydrolysis at 20 C yields glycerol and a polymer formed by galactose and arabinose (in a ratio of 1:1) which is resistant to a second oxidation. Therefore, the polysaccharide is probably formed by a main chain of glactose linked 1,3 and arabinose linked 1,2 or 1,3 or both, and nonreducing side chains of arabofuranose residues. The intact polysaccharide cross-reacts with sera from patients with active tuberculosis, and this, as well as the homologous reaction, is abolished by oxidation with periodate. PMID:16562050

  17. Transporters in the Paracoccidioides brasiliensis transcriptome: insights on drug resistance.

    PubMed

    Costa, Christiane da Silva; Albuquerque, Flávia Caixeta; Andrade, Rosângela Vieira; Oliveira, Gina Camilo de; Almeida, Mauro Fernandes de; Brigido, Marcelo de Macedo; Maranhão, Andrea Queiroz

    2005-06-30

    In the struggle for life, the capacity of microorganisms to synthesize and secrete toxic compounds (inhibiting competitors) plays an important role in successful survival of these species. This ability must come together with the capability of being unaffected by these same compounds. Several mechanisms are thought to avoid the toxic effects. One of them is toxin extrusion from the intracellular environment to the outside vicinity, using special transmembrane proteins, referred to as transporters. These proteins are also important for other reasons, since most of them are involved in nutrient uptake and cellular excretion. In cancer cells and in pathogens, and particularly in fungi, some of these proteins have been pointed out as responsible for an important phenotype known as multidrug resistance (MDR). In the present study, we tried to identify in the Paracoccidioides brasiliensis transcriptome, transporter-ortholog genes from the two major classes: ATP binding cassette and major facilitator superfamily transporter. We found 22 groups with good similarity with other fungal ATP binding cassette transporters, and four Paracoccidioides brasilienses assembled expressed sequence tags that probably code for major facilitator superfamily proteins. We also focused on fungicide resistance orthologs already characterized in other pathogenic fungi. We were able to find homologs to C. albicans CDR1, CDR2, and MDR1, Saccharomyces cerevisiae PDR5 and Aspergillus AtrF genes, all of them related to azole resistance. As current treatment for paracoccidioidomycosis mainly uses azole derivatives, the presence of these genes can be postulated to play a similar role in P. brasiliensis, warning us for the possibility of resistant isolate emergence.

  18. Antimicrobial effect of farnesol, a Candida albicans quorum sensing molecule, on Paracoccidioides brasiliensis growth and morphogenesis

    PubMed Central

    Derengowski, Lorena S; De-Souza-Silva, Calliandra; Braz, Shélida V; Mello-De-Sousa, Thiago M; Báo, Sônia N; Kyaw, Cynthia M; Silva-Pereira, Ildinete

    2009-01-01

    Background Farnesol is a sesquiterpene alcohol produced by many organisms, and also found in several essential oils. Its role as a quorum sensing molecule and as a virulence factor of Candida albicans has been well described. Studies revealed that farnesol affect the growth of a number of bacteria and fungi, pointing to a potential role as an antimicrobial agent. Methods Growth assays of Paracoccidioides brasiliensis cells incubated in the presence of different concentrations of farnesol were performed by measuring the optical density of the cultures. The viability of fungal cells was determined by MTT assay and by counting the colony forming units, after each farnesol treatment. The effects of farnesol on P. brasiliensis dimorphism were also evaluated by optical microscopy. The ultrastructural morphology of farnesol-treated P. brasiliensis yeast cells was evaluated by transmission and scanning electron microscopy. Results In this study, the effects of farnesol on Paracoccidioides brasiliensis growth and dimorphism were described. Concentrations of this isoprenoid ranging from 25 to 300 μM strongly inhibited P. brasiliensis growth. We have estimated that the MIC of farnesol for P. brasiliensis is 25 μM, while the MLC is around 30 μM. When employing levels which don't compromise cell viability (5 to 15 μM), it was shown that farnesol also affected the morphogenesis of this fungus. We observed about 60% of inhibition in hyphal development following P. brasiliensis yeast cells treatment with 15 μM of farnesol for 48 h. At these farnesol concentrations we also observed a significant hyphal shortening. Electron microscopy experiments showed that, despite of a remaining intact cell wall, P. brasiliensis cells treated with farnesol concentrations above 25 μM exhibited a fully cytoplasmic degeneration. Conclusion Our data indicate that farnesol acts as a potent antimicrobial agent against P. brasiliensis. The fungicide activity of farnesol against this pathogen is

  19. Antagonistic Activity of Nocardia brasiliensis PTCC 1422 Against Isolated Enterobacteriaceae from Urinary Tract Infections.

    PubMed

    Jalali, Hossnieh Kafshdar; Salamatzadeh, Abdolreza; Jalali, Arezou Kafshdar; Kashani, Hamed Haddad; Asbchin, Salman Ahmadi; Issazadeh, Khosro

    2016-03-01

    The main drawback of current antibiotic therapies is the emergence and rapid increase in antibiotic resistance. Nocardiae are aerobic, Gram-positive, catalase-positive, non-motile actinomycetes. Nocardia brasiliensis was reported as antibiotic producer. The purpose of the study was to determine antibacterial activity of N. brasiliensis PTCC 1422 against isolated Enterobacteriaceae from urinary tract infections (UTIs). The common bacteria from UTIs were isolated from hospital samples. Antimicrobial susceptibility test was performed for the isolated pathogens using Kirby-Bauer disk diffusion method according to clinical and Laboratory Standards Institute guideline. Antagonistic activity of N. brasiliensis PTCC 1422 was examined with well diffusion methods. Supernatant of N. brasiliensis PTCC 1422 by submerged culture was analyzed with gas chromatography-mass spectrometry. Isolated strains included Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Proteus mirabilis. The most common pathogen isolated was E. coli (72.5%). Bacterial isolates revealed the presence of high levels of antimicrobial resistances to ceftriaxone and low levels of resistance to cephalexin. Supernatant of N. brasiliensis PTCC 1422 showed antibacterial activity against all of the isolated microorganisms in well diffusion method. The antibiotic resistance among the uropathogens is an evolving process, so a routine surveillance to monitor the etiologic agents of UTI and the resistance pattern should be carried out timely to choose the most effective empirical treatment by the physicians. Our present investigation indicates that the substances present in the N. brasiliensis PTCC 1422 could be used to inhibit the growth of human pathogen. Antibacterial resistance among bacterial uropathogen is an evolving process. Therefore, in the field on the need of re-evaluation of empirical treatment of UTIs, our present. The study has demonstrated that N. brasiliensis PTCC 1422 has a high potential

  20. Multipartite asymmetric quantum cloning

    SciTech Connect

    Iblisdir, S.; Gisin, N.; Acin, A.; Cerf, N.J.; Filip, R.; Fiurasek, J.

    2005-10-15

    We investigate the optimal distribution of quantum information over multipartite systems in asymmetric settings. We introduce cloning transformations that take N identical replicas of a pure state in any dimension as input and yield a collection of clones with nonidentical fidelities. As an example, if the clones are partitioned into a set of M{sub A} clones with fidelity F{sup A} and another set of M{sub B} clones with fidelity F{sup B}, the trade-off between these fidelities is analyzed, and particular cases of optimal N{yields}M{sub A}+M{sub B} cloning machines are exhibited. We also present an optimal 1{yields}1+1+1 cloning machine, which is an example of a tripartite fully asymmetric cloner. Finally, it is shown how these cloning machines can be optically realized.

  1. Aristotle and headless clones.

    PubMed

    Mosteller, Timothy

    2005-01-01

    Cloned organisms can be genetically altered so that they do not exhibit higher brain functioning. This form of therapeutic cloning allows for genetically identical organs and tissues to be harvested from the clone for the use of the organism that is cloned. "Spare parts" cloning promises many opportunities for future medical advances. What is the ontological and ethical status of spare parts, headless clones? This paper attempts to answer this question from the perspective of Aristotle's view of the soul. Aristotle's metaphysics as applied to his view of biological essences generates an ethic that can contribute to moral reasoning regarding the use of headless spare parts clones. The task of this paper is to show the implications that Aristotle's view of the soul, if it is true, would have on the ethics of headless, spare parts cloning.

  2. Ethical issues in cloning.

    PubMed

    Satris, S

    2000-01-01

    There is great public concern with the ethics of human cloning. This paper briefly examines some of what I identify as pseudo-problems or myths associated with cloning, and some of the more substantial ethical concerns.

  3. Draft Genome Sequence of Pseudozyma brasiliensis sp. nov. Strain GHG001, a High Producer of Endo-1,4-Xylanase Isolated from an Insect Pest of Sugarcane.

    PubMed

    Oliveira, Juliana Velasco de Castro; Dos Santos, Renato Augusto Corrêa; Borges, Thuanny A; Riaño-Pachón, Diego Mauricio; Goldman, Gustavo Henrique

    2013-12-19

    Here, we present the nuclear and mitochondrial genome sequences of Pseudozyma brasiliensis sp. nov. strain GHG001. P. brasiliensis sp. nov. is the closest relative of Pseudozyma vetiver. P. brasiliensis sp. nov. is capable of growing on xylose or xylan as a sole carbon source and has great biotechnological potential.

  4. Draft Genome Sequence of Pseudozyma brasiliensis sp. nov. Strain GHG001, a High Producer of Endo-1,4-Xylanase Isolated from an Insect Pest of Sugarcane

    PubMed Central

    Oliveira, Juliana Velasco de Castro; dos Santos, Renato Augusto Corrêa; Borges, Thuanny A.

    2013-01-01

    Here, we present the nuclear and mitochondrial genome sequences of Pseudozyma brasiliensis sp. nov. strain GHG001. P. brasiliensis sp. nov. is the closest relative of Pseudozyma vetiver. P. brasiliensis sp. nov. is capable of growing on xylose or xylan as a sole carbon source and has great biotechnological potential. PMID:24356824

  5. Cloning in reproductive medicine.

    PubMed

    Illmensee, K

    2001-08-01

    This review article summarizes the historical development of mammalian cloning, presents current advances and presumed risk factors in the field of reproductive cloning, discusses possible clinical applications of therapeutic and diagnostic cloning and outlines prospective commercial trends in pharmaceutical cloning. Predictable progress in biotechnology and stem cell engineering should prove to be advantageous for patients' health and for novel benefits in reproductive and regenerative medicine.

  6. Phenotypic variability confirmed by nuclear ribosomal DNA suggests a possible natural hybrid zone of Triatoma brasiliensis species complex.

    PubMed

    Costa, Jane; Bargues, Maria Dolores; Neiva, Vanessa Lima; Lawrence, Gena G; Gumiel, Marcia; Oliveira, Genova; Cabello, Pedro; Lima, Marli Maria; Dotson, Ellen; Provance, David William; Almeida, Carlos Eduardo; Mateo, Lucia; Mas-Coma, Santiago; Dujardin, Jean Pierre

    2016-01-01

    Triatoma brasiliensis macromelasoma occurs in Pernambuco state, Brazil, which is situated between the distribution areas of Triatoma brasiliensis brasiliensis (north) and Triatoma juazeirensis (south). T. b. macromelasoma displays greater variations in its chromatic phenotype than either T. b. brasiliensis or T. juazeirensis, and patterns reminiscent of one or the other. Experimental crosses from each of these members of the T. brasiliensis species complex generated fertile offspring suggesting that viable hybrids could be present in nature, despite their significant genetic distances. Considering the geographical position of occurrence of the T. b. macromelasoma (in Pernambuco) it was proposed to be an area capable of supporting natural hybridization between T. b. brasiliensis and T. juazeirensis. Since phenotypic variability is expected, this study investigated the existence of intermediate chromatic phenotypes for T. b. macromelasoma in various locations in areas between the T. b. brasiliensis and T. juazeirensis occurrences. Thirteen different color patterns were for the first time characterized and nine of those displayed intermediate phenotypes. Molecular analysis performed using ribosomal DNA intergenic region, grouped all within the T. brasiliensis complex. The intermediate chromatic phenotypes, molecular analysis and experimental crosses all support the distinction of a zone of hybridization that gave rise to the T. b. macromelasoma through homoploidal evolution.

  7. Seroepidemiology of Paracoccidioides brasiliensis infection in horses from Rio Grande do Sul, Brazil

    PubMed Central

    Albano, Ana Paula Neuschrank; Klafke, Gabriel Baracy; Brandolt, Tchana Martinez; Da Hora, Vanusa Pousada; Nogueira, Carlos Eduardo Wayne; Xavier, Melissa Orzechowski; Meireles, Mário Carlos Araújo

    2015-01-01

    Paracoccidioides brasiliensis is the etiological agent of the major systemic mycosis in Brazil, called paracoccidioidomycosis. Although the Rio Grande do Sul is considered an endemic area of the disease, there are few studies on the ecology of P. brasiliensis in the state. Therefore, this study aimed to evaluate the infection of P. brasiliensis in horses from the mesoregion of Southwest Riograndense, using these animals as sentinels. Serological techniques, such as double immunodiffusion in agar gel (AGID) and indirect ELISA, were performed to detect the anti-gp43 P. brasiliensis antibody in horses from five different farms in the region of Bagé, RS, Brazil. Serology was performed in 200 Pure Blood English horses up to two years of age that were born and raised exclusively at the farms. Of these horses, 12% had anti-gp43 antibodies according to the ELISA results, with rates ranging from 0 to 30% according to the farm of origin (p < 0.001). Based on the immunodiffusion results, all equine serum samples were negative. These results indicate the presence of the fungus P. brasiliensis in the middle region of the southwestern state of Rio Grande do Sul, Brazil. PMID:26273267

  8. Seroepidemiology of Paracoccidioides brasiliensis infection in horses from Rio Grande do Sul, Brazil.

    PubMed

    Albano, Ana Paula Neuschrank; Klafke, Gabriel Baracy; Brandolt, Tchana Martinez; Da Hora, Vanusa Pousada; Nogueira, Carlos Eduardo Wayne; Xavier, Melissa Orzechowski; Meireles, Mário Carlos Araújo

    2015-06-01

    Paracoccidioides brasiliensis is the etiological agent of the major systemic mycosis in Brazil, called paracoccidioidomycosis. Although the Rio Grande do Sul is considered an endemic area of the disease, there are few studies on the ecology of P. brasiliensis in the state. Therefore, this study aimed to evaluate the infection of P. brasiliensis in horses from the mesoregion of Southwest Riograndense, using these animals as sentinels. Serological techniques, such as double immunodiffusion in agar gel (AGID) and indirect ELISA, were performed to detect the anti-gp43 P. brasiliensis antibody in horses from five different farms in the region of Bagé, RS, Brazil. Serology was performed in 200 Pure Blood English horses up to two years of age that were born and raised exclusively at the farms. Of these horses, 12% had anti-gp43 antibodies according to the ELISA results, with rates ranging from 0 to 30% according to the farm of origin (p < 0.001). Based on the immunodiffusion results, all equine serum samples were negative. These results indicate the presence of the fungus P. brasiliensis in the middle region of the southwestern state of Rio Grande do Sul, Brazil.

  9. Sporotrichosis in Rio de Janeiro, Brazil: Sporothrix brasiliensis Is Associated with Atypical Clinical Presentations

    PubMed Central

    Almeida-Paes, Rodrigo; de Oliveira, Manoel Marques Evangelista; Freitas, Dayvison Francis Saraiva; do Valle, Antônio Carlos Francesconi; Zancopé-Oliveira, Rosely Maria; Gutierrez-Galhardo, Maria Clara

    2014-01-01

    Background There have been several recent changes in the taxonomy of Sporothrix schenckii as well as new observations regarding the clinical aspects of sporotrichosis. In this study, we determined the identification of the Sporothrix species associated with both classic and unusual clinical aspects of sporotrichosis observed in the endemic area of sporotrichosis in Rio de Janeiro, Brazil. Methodology/Principal Findings To verify whether S. brasiliensis is associated with clinical manifestations of sporotrichosis, a cross-sectional study was performed in which Sporothrix isolates from 50 patients with different clinical manifestations were analyzed and their isolates were studied by phenotypic and genotypic methods. Data from these patients revealed a distinct clinical picture and therapeutic response in infections caused by Sporothrix brasiliensis (n = 45) compared to patients with S. schenckii sensu stricto (n = 5). S. brasiliensis was associated with disseminated cutaneous infection without underlying disease, hypersensitivity reactions, and mucosal infection, whereas patients with S. schenckii presented with less severe and more often localized disease, similar to the majority of previously described sporotrichosis cases. Interestingly, S. brasiliensis-infected patients overall required shorter durations of itraconazole (median 16 weeks) compared to the individuals with S. schenckii (median 24 weeks). Conclusions/Significance These findings suggest that Sporothrix species are linked to different clinical manifestations of sporotrichosis and that S. brasiliensis is effectively treated with oral itraconazole. PMID:25233227

  10. Study of nucleolar behavior during spermatogenesis in Martarega brasiliensis (Heteroptera, Notonectidae).

    PubMed

    Pereira, L L V; Alevi, K C C; Moreira, F F F; Barbosa, J F; Silistino-Souza, E R; Silva Júnior, F C; Souza-Firmino, T S; Banho, C A; Itoyama, M M

    2015-08-07

    Few cytogenetic studies have been undertaken using aquatic heteropterans and the nucleolar behavior of these insects has been described in only four species, Limnogonus aduncus, Brachymetra albinerva, Halobatopsis platensis, and Cylindrostethus palmaris. The nucleolus is a cellular structure related to biosynthetic activity and it exhibits a peculiar behavior in the heteropterans of the Triatominae subfamily; it persists during all stages of meiosis. Thus, this study aims to analyze spermatogenesis in Martarega brasiliensis, with an emphasis on nucleolar behavior. Twenty M. brasiliensis adult males were used and collected from the Municipal reservoir in the city of São José do Rio Preto, São Paulo, Brazil. The species were fixed in methanol:acetic acid (3:1), then dissected, and the testicles were extracted, torn apart, and impregnated with silver ions. During prophase, the nuclei of M. brasiliensis were composed of the nucleolus and nucleolar corpuscles, which varied in number from one to four, emphasizing that this insect has great synthetic activity during meiosis. The analysis of cells in metaphase I showed that M. brasiliensis presents a nucleolar organizing region in at least one autosome. Furthermore, the phenomenon of nucleolar persistence was not observed. All spermatids presented nucleolar markings that varied in number and position according to the stage of elongation. Moreover, it was also possible to highlight the presence of a vesicle in spermatids. Thus, this paper describes the nucleolar behavior of M. brasiliensis and highlights important characteristics during spermatogenesis, thus, increasing the knowledge about the biology of these aquatic heteropterans.

  11. In vitro susceptibility of antifungal drugs against Sporothrix brasiliensis recovered from cats with sporotrichosis in Brazil.

    PubMed

    Brilhante, Raimunda Sâmia Nogueira; Rodrigues, Anderson Messias; Sidrim, José Júlio Costa; Rocha, Marcos Fábio Gadelha; Pereira, Sandro Antonio; Gremião, Isabella Dib Ferreira; Schubach, Tânia Maria Pacheco; de Camargo, Zoilo Pires

    2016-03-01

    Sporotrichosis is an important subcutaneous mycosis of humans and animals. Classically, the disease is acquired upon traumatic inoculation of Sporothrix propagules from contaminated soil and plant debris. In addition, the direct horizontal transmission of Sporothrix among animals and the resulting zoonotic infection in humans highlight an alternative and efficient rout of transmission through biting and scratching. Sporothrix brasiliensis is the most virulent species of the Sporothrix schenckii complex and is responsible for the long-lasting outbreak of feline sporotrichosis in Brazil. However, antifungal susceptibility data of animal-borne isolates is scarce. Therefore, this study evaluated the in vitro activity of amphotericin B, caspofungin, itraconazole, voriconazole, fluconazole, and ketoconazole against animal-borne isolates of S. brasiliensis. The susceptibility tests were performed through broth microdilution (M38-A2). The results show the relevant activity of itraconazole, amphotericin B, and ketoconazole against S. brasiliensis, with the following MIC ranges: 0.125-2, 0.125-4 and 0.0312-2 μg/ml, respectively. Caspofungin was moderately effective, displaying higher variation in MIC values (0.25-64 μg/ml). Voriconazole (2-64 μg/ml) and fluconazole (62.5-500 μg/ml) showed low activity against S. brasiliensis strains. This study contributed to the characterization of the in vitro antifungal susceptibility of strains of S. brasiliensis recovered from cats with sporotrichosis, which have recently been considered the main source of human infections.

  12. Quick and clean cloning.

    PubMed

    Thieme, Frank; Marillonnet, Sylvestre

    2014-01-01

    Identification of unknown sequences that flank known sequences of interest requires PCR amplification of DNA fragments that contain the junction between the known and unknown flanking sequences. Since amplified products often contain a mixture of specific and nonspecific products, the quick and clean (QC) cloning procedure was developed to clone specific products only. QC cloning is a ligation-independent cloning procedure that relies on the exonuclease activity of T4 DNA polymerase to generate single-stranded extensions at the ends of the vector and insert. A specific feature of QC cloning is the use of vectors that contain a sequence called catching sequence that allows cloning specific products only. QC cloning is performed by a one-pot incubation of insert and vector in the presence of T4 DNA polymerase at room temperature for 10 min followed by direct transformation of the incubation mix in chemo-competent Escherichia coli cells.

  13. Temporal auditory summation in the echolocating bat, Tadarida brasiliensis.

    PubMed

    Schmidt, S; Thaller, J

    1994-06-15

    Auditory thresholds improve with increasing signal duration within the maximum integration time of the auditory system, a phenomenon called temporal summation. The temporal summation function is a basic characteristic of particular relevance for bat sonar, as it determines the ability to detect targets with short echolocation calls. Temporal summation was studied in 6 Mexican free-tailed bats (Tadarida brasiliensis) in a forced two-choice behavioural test. Masked auditory thresholds for 40-kHz test tone pulses with durations between 2 ms and 400 ms were determined in broadband noise of two different spectrum levels (-18 dB, +17 dB). At both masker levels, thresholds decreased by considerably more than 10 dB per decade of duration. The time constants of the summation functions, which are a measure of the maximum integration time, shortened significantly with increasing masker level from 62 ms to 14 ms. The steep summation functions are only partly accounted for by spectral splatter. This suggests that the bats are capable of a neural overintegration of sound intensity. Finally, it is shown that such short time constants are typical for echolocating animals, and the implications of the found summation functions for echolocation are considered.

  14. Cryptic species of Paracoccidioides brasiliensis: impact on paracoccidioidomycosis immunodiagnosis

    PubMed Central

    Machado, Gabriel Capella; Moris, Daniela Vanessa; Arantes, Thales Domingos; Silva, Luciane Regina Franciscone; Theodoro, Raquel Cordeiro; Mendes, Rinaldo Pôncio; Vicentini, Adriana Pardini; Bagagli, Eduardo

    2013-01-01

    We aimed to evaluate whether the occurrence of cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii, has implications in the immunodiagnosis of paracoccidioidomycosis (PCM). Small quantities of the antigen gp43 were found in culture filtrates of P. lutzii strains and this molecule appeared to be more variable within P. lutzii because the synonymous-nonsynonymous mutation rate was lower, indicating an evolutionary process different from that of the remaining genotypes. The production of gp43 also varied between isolates belonging to the same species, indicating that speciation events are important, but not sufficient to fully explain the diversity in the production of this antigen. The culture filtrate antigen AgEpm83, which was obtained from a PS3 isolate, showed large quantities of gp43 and reactivity by immunodiffusion assays, similar to the standard antigen (AgB-339) from an S1 isolate. Furthermore, AgEpm83 was capable of serologically differentiating five serum samples from patients from the Botucatu and Jundiaí regions. These patients had confirmed PCM but, were non-reactive to the standard antigen, thus demonstrating an alternative for serological diagnosis in regions in which S1 and PS2 occur. We also emphasise that it is not advisable to use a single antigen preparation to diagnose PCM, a disease that is caused by highly diverse pathogens. PMID:23903981

  15. Geodermatophilus brasiliensis sp. nov., isolated from Brazilian soil.

    PubMed

    Bertazzo, Marcelo; Montero-Calasanz, Maria del Carmen; Martinez-Garcia, Manuel; Spröer, Cathrin; Schumann, Peter; Kroppenstedt, Reiner M; Stackebrandt, Erko; Klenk, Hans-Peter; Fiedler, Hans-Peter

    2014-08-01

    A Gram-reaction-positive bacterial isolate, designated Tü 6233(T), with rudimentary, coral-pink vegetative mycelium that formed neither aerial mycelium nor spores, was isolated from a Brazilian soil sample. Chemotaxonomic and molecular characteristics of the isolate matched those described for members of the genus Geodermatophilus. Cell-wall hydrolysates contained meso-diaminopimelic acid as the diagnostic diamino acid and galactose as the diagnostic sugar. The major fatty acids were iso-C(16 : 0), iso-C(15 : 0) and C(17 : 1)ω8c and the predominant menaquinone was MK-9(H4). The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylinositol, an unknown glycophospholipid and an unknown phospholipid. The DNA G+C content of the strain was 75.4 mol%. The 16S rRNA gene sequence identity with members of the genus Geodermatophilus was 94.2-98.7%. Based on phenotypic, chemotaxonomic and phylogenetic data, strain Tü 6233(T) is proposed to represent a novel species, Geodermatophilus brasiliensis sp. nov., with the type strain Tü 6233(T) ( = DSM 44526(T) = CECT 8402(T)). © 2014 IUMS.

  16. Reaginic antibodies and immunity to Nippostrongylus brasiliensis in the rat

    PubMed Central

    Jones, Valerie E.; Ogilvie, Bridget M.

    1967-01-01

    1. Passive transfer of immunity to Nippostrongylus brasiliensis with pooled antiserum from immune rats was neutralized in vivo by intravenous injection of small amounts of a saline extract of adult worms. This inhibition of protection was associated with systemic anaphylaxis and appeared to result from the neutralization of protective antibodies. 2. Serum from infected rats was fractionated by G-200 Sephadex gel-filtration. Reaginic antibodies were shown to be intermediate in molecular size between 7S and 19S globulins in sera from both singly and multiply infected animals. In immunoelectrophoresis they migrated with fast immunoglobulins but could not be related to either IgG or IgA rat immunoglobulins. The same serum fractions gave both homologous passive cutaneous anaphylaxis (PCA) and systemic anaphylaxis. 3. Blocking antibodies were found both in the 7S and 19S fractions after separation on G-200 Sephadex. These antibodies were found in sera from rats immunized with worm extracts as well as in sera from singly and multiply infected animals. 4. The saline extract of adult worms was fractionated on G-200 Sephadex. The isolated antigenic material (allergen) for both homologous PCA and systemic anaphylaxis seemed to be a protein with a molecular weight of approximately 12,000–17,000. ImagesFIG. 4FIG. 6FIG. 8 PMID:6066617

  17. Isolation and purification of two immunodominant antigens from Nocardia brasiliensis.

    PubMed Central

    Vera-Cabrera, L; Salinas-Carmona, M C; Welsh, O; Rodriguez, M A

    1992-01-01

    Two immunogenic proteins from a crude extract of Nocardia brasiliensis were purified to homogeneity. A 61-kDa protein (P61) was isolated from a 50% ammonium sulfate precipitate in two steps. Initially, P61 was obtained by electroelution in a 10% nondenatured preparative polyacrylamide gel electrophoresis (PAGE). In a second step, the eluate from the nondenatured gel was run in a 12% sodium dodecyl sulfate (SDS) preparative polyacrylamide gel. After elution, a single band was demonstrated by SDS-PAGE and Western blot (immunoblot). Also, a 24-kDa immunogenic protein (P24) was isolated by gel filtration in a Sephadex G-100 column and then by electroelution in a 12% nondenatured polyacrylamide gel. In a previous paper, we showed by Western blot assays that these proteins are recognized by the sera of mycetoma patients and not by sera from mycobacterial-infected or healthy individuals. We consider these proteins to be good candidates for the study of the host-parasite relationship in nocardial infections. The possible clinical application of these purified antigens in a serological diagnosis is discussed. Images PMID:1583118

  18. Sporothrix brasiliensis outbreaks and the rapid emergence of feline sporotrichosis.

    PubMed

    Sanchotene, Karine Ortiz; Madrid, Isabel Martins; Klafke, Gabriel Baracy; Bergamashi, Mariana; Della Terra, Paula Portella; Rodrigues, Anderson Messias; de Camargo, Zoilo Pires; Xavier, Melissa Orzechowski

    2015-11-01

    Sporotrichosis is the main subcutaneous mycosis in Brazil, and is caused by Sporothrix schenckii and allied species. Sporothrix propagules present on soil and plant debris may be traumatically inoculated into the cutaneous/ subcutaneous tissues of the warm-blooded host. An alternative route involves direct animal-animal and animal-human transmissions through deep scratches and bites of diseased cats. Sporotrichosis is much more common than previously appreciated with several cases emerging over the years especially in South and Southeast Brazil. We conducted an epidemiological surveillance in endemic areas of feline sporotrichosis in the southern region of Rio Grande do Sul state, Brazil. Over the last 5-year period the number of feline sporotrichosis in Rio Grande increased from 0.75 new cases per month in 2010 to 3.33 cases per month in 2014. The wide geographic distribution of diagnosed cases highlights the dynamics of Sporothrix transmission across urban areas with high population density. Molecular identification down to species level by PCR-RFLP of cat-transmitted Sporothrix revealed the emergence of the clonal offshoot S. brasiliensis during feline outbreaks; this scenario is similar to the epidemics taking place in the metropolitan areas of Rio de Janeiro and São Paulo. Controlling and preventing sporotrichosis outbreaks are essential steps to managing the disease among humans and animals.

  19. The mitochondrial genome from the thermal dimorphic fungus Paracoccidioides brasiliensis.

    PubMed

    Cardoso, Maria Angélica G; Tambor, José Humberto M; Nobrega, Francisco G

    2007-07-01

    We present here the sequence of the mitochondrial DNA of the pathogenic thermodimorphic fungus Paracoccidioides brasiliensis, agent of an endemic disease in most South American countries. The sequenced genome has 71 334 bp and is organized as a circular molecule with two gaps of unknown size flanking the middle exon of the nad5 gene. We located genes coding for the three subunits of the ATP synthase (atp6, atp8 and atp9), the apocytochrome b (cob), three subunits of the cytochrome c oxidase enzyme complex (cox1, cox2 and cox3), seven subunits of the reduced nicotinamide adenine dinucleotide ubiquinone oxidoreductase (nad1, nad2, nad3, nad4, nad5, nad6 and nad4L) and the large (rnl) and small (rns) subunits of ribosomal RNA. Two maturases and a ribosomal protein (rms5) are located inside introns. Twenty-five tRNAs were identified with acceptors for all 20 amino acids. Seven polypurine/polypyrimidine tracts (140-240 bp) have been found in this genome. All genes are in the same orientation over the genome, while their order is closest to the mitochondrial genomes from Penicillium marneffei and Aspergillus nidulans.

  20. Heterologous expression, purification, and immunological reactivity of a recombinant HSP60 from Paracoccidioides brasiliensis.

    PubMed

    Cunha, Daniela A; Zancopé-Oliveira, Roseli M; Sueli, M; Felipe, S; Salem-Izacc, Silvia M; Deepe, George S; Soares, Célia M A

    2002-03-01

    The complete coding cDNA of HSP60 from Paracoccidioides brasiliensis was overexpressed in an Escherichia coli host to produce high levels of recombinant protein. The protein was purified by affinity chromatography. A total of 169 human serum samples were tested for reactivity by Western blot analysis with the purified HSP60 recombinant protein. Immunoblots indicated that the recombinant P. brasiliensis HSP60 was recognized by antibodies in 72 of 75 sera from paracoccidioidomycosis patients. No cross-reactivity was detected with individual sera from patients with aspergillosis, sporotrichosis, cryptococcosis, and tuberculosis. Reactivity to HSP60 was observed in sera from 9.52% of control healthy individuals and 11.5% of patients with histoplasmosis. The high sensitivity and specificity (97.3 and 92.5%, respectively) for HSP60 suggested that the recombinant protein can be used singly or in association with other recombinant antigens to detect antibody responses in P. brasiliensis-infected patients.

  1. Heterologous Expression, Purification, and Immunological Reactivity of a Recombinant HSP60 from Paracoccidioides brasiliensis

    PubMed Central

    Cunha, Daniela A.; Zancopé-Oliveira, Roseli M.; Sueli, M.; Felipe, S.; Salem-Izacc, Silvia M.; Deepe Jr., George S.; Soares, Célia M. A.

    2002-01-01

    The complete coding cDNA of HSP60 from Paracoccidioides brasiliensis was overexpressed in an Escherichia coli host to produce high levels of recombinant protein. The protein was purified by affinity chromatography. A total of 169 human serum samples were tested for reactivity by Western blot analysis with the purified HSP60 recombinant protein. Immunoblots indicated that the recombinant P. brasiliensis HSP60 was recognized by antibodies in 72 of 75 sera from paracoccidioidomycosis patients. No cross-reactivity was detected with individual sera from patients with aspergillosis, sporotrichosis, cryptococcosis, and tuberculosis. Reactivity to HSP60 was observed in sera from 9.52% of control healthy individuals and 11.5% of patients with histoplasmosis. The high sensitivity and specificity (97.3 and 92.5%, respectively) for HSP60 suggested that the recombinant protein can be used singly or in association with other recombinant antigens to detect antibody responses in P. brasiliensis-infected patients. PMID:11874881

  2. Reproductive Biology of Triatoma brasiliensis (Hemiptera, Triatominae) During the Imaginal Molt.

    PubMed

    Alevi, Kaio Cesar Chaboli; Guerra, Ana Letícia; Imperador, Carlos Henrique Lima; da Rosa, João Aristeu; de Azeredo-Oliveira, Maria Tercília Vilela

    2016-03-01

    The triatomines are vectors of the protozoan Trypanosoma cruzi, etiologic agent of Chagas disease. These insects are sexually active after the imaginal molt. Some aspects have been studied in Triatoma brasiliensis during the imaginal molt, such as autogeny in virgin females and the relationship between blood ingestion by fifth instar nymph and the realization of the imaginal molt. Thus, to aid in the understanding of reproductive biology and developmental physiology of these vectors, this article analyzes the spermatogenesis of T. brasiliensis during the imaginal molt. The analysis of the seminiferous tubules from males in the fifth instar during imaginal molt has demonstrated that T. brasiliensis has only a few spermatids and a plentiful quantity of sperm. Thus, we suggest that during imaginal molt the cell division is disrupted aiming to reduce energy costs and the differentiation into sperm is stimulated to ensure the paternity of the adult male. © The American Society of Tropical Medicine and Hygiene.

  3. Nippostrongylus brasiliensis and Ascaridia galli: mitochondrial respiration in free-living and parasitic stages.

    PubMed

    Fry, M; Jenkins, D C

    1983-08-01

    Aerobic respiratory pathways have been delineated and respiratory efficiency has been assessed in mitochondria isolated from embryonated eggs, infective larvae, and adult Nippostrongylus brasiliensis and Ascaridia galli. Mitochondrial respiration in free-living stages of N. brasiliensis is mediated mainly by a mammalian-like antimycin A- and cyanide-sensitive pathway; specific respiratory activity is high and oxidative phosphorylation efficient. In mitochondria of adult N. brasiliensis, antimycin A- and cyanide-sensitive respiration is decreased relative to respiration though an alternative pathway, and specific respiratory activity and mitochondrial efficiency are lower. Respiration in mitochondria from embryonated eggs and tissues of adult A. galli is comparable, and apparently mediated by an antimycin A- and cyanide-insensitive alternative respiratory pathway; no evidence for the presence of a mammalian-like respiratory pathway in embryonated eggs of A. galli was found. The results of this study are compared to mitochondrial respiration in eggs, larvae, and adult body wall muscle of Ascaris suum.

  4. Diversity and antimicrobial potential of culturable heterotrophic bacteria associated with the endemic marine sponge Arenosclera brasiliensis.

    PubMed

    Rua, Cintia P J; Trindade-Silva, Amaro E; Appolinario, Luciana R; Venas, Tainá M; Garcia, Gizele D; Carvalho, Lucas S; Lima, Alinne; Kruger, Ricardo; Pereira, Renato C; Berlinck, Roberto G S; Valle, Rogério A B; Thompson, Cristiane C; Thompson, Fabiano

    2014-01-01

    Marine sponges are the oldest Metazoa, very often presenting a complex microbial consortium. Such is the case of the marine sponge Arenosclera brasiliensis, endemic to Rio de Janeiro State, Brazil. In this investigation we characterized the diversity of some of the culturable heterotrophic bacteria living in association with A. brasiliensis and determined their antimicrobial activity. The genera Endozoicomonas (N = 32), Bacillus (N = 26), Shewanella (N = 17), Pseudovibrio (N = 12), and Ruegeria (N = 8) were dominant among the recovered isolates, corresponding to 97% of all isolates. Approximately one third of the isolates living in association with A. brasiliensis produced antibiotics that inhibited the growth of Bacillus subtilis, suggesting that bacteria associated with this sponge play a role in its health.

  5. Purinergic effects of a hydroalcoholic Agaricus brasiliensis (A. blazei) extract on liver functions.

    PubMed

    de Oliveira, Andrea L; Eler, G Jacklin; Bracht, Adelar; Peralta, Rosane M

    2010-06-23

    The effects of a hydroalcoholic extract of Agaricus brasiliensis (A. blazei) on functional parameters in the perfused rat liver were examined with emphasis on its content of nucleotides and nucleosides. Several nucleosides and nucleotides were identified in the A. brasiliensis extract, which was active on several liver functions. A significant part of the effects is the result of the purinergic action of nucleosides and nucleotides: pressure increment, glycogenolysis stimulation, transient inhibition of oxygen consumption, and redox state changes. Other phenomena such as the stimulation of gluconeogenesis, ureogenesis, and oxygen consumption are more likely consequences of the metabolic transformation of substrates contained within the extract, especially amino acids. It seems apparent that consumption of A. brasiliensis represents not only the ingestion of metabolic precursors but also the ingestion of substances that, even at low concentrations, can exert important signaling functions in the liver as well as in the organism as a whole.

  6. Royal sun medicinal mushroom, Agaricus brasiliensis Ka21 (higher Basidiomycetes), as a functional food in humans.

    PubMed

    Yamanaka, Daisuke; Liu, Ying; Motoi, Masuro; Ohno, Naohito

    2013-01-01

    The Royal Sun medicinal mushroom, Agaricus brasiliensis, is used as a natural health product. In Japan, however, the quality control of some of these mushroom products has been viewed as a safety problem. Focusing on the quality control of A. brasiliensis KA21, we have performed several safety studies. To date, we have established evidence that this mushroom can be used safely as an immunostimulant and to mediate biochemical parameters associated with obesity or diabetes. Furthermore, to improve the manufacturing process of this mushroom, we have studied the relationship between its pharmaceutical actions and the conditions of its cultivation and thermal management. The purpose of this review is to report the findings of basic and clinical studies of the fruit body of A. brasiliensis KA21.

  7. Increase in virulence of Sporothrix brasiliensis over five years in a patient with chronic disseminated sporotrichosis.

    PubMed

    Freitas, Dayvison F S; Santos, Suelen S; Almeida-Paes, Rodrigo; de Oliveira, Manoel M E; do Valle, Antonio C F; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely M; Nosanchuk, Joshua D

    2015-01-01

    The metropolitan region of Rio de Janeiro is hyperendemic for cat-associated sporotrichosis. This study aimed to assess the virulence of serial Sporothrix isolates from a 61-year-old male patient with chronic, destructive disseminated sporotrichosis. Five Sporothrix isolates were cultured from skin exudates and bone samples over a 5-year period, and all were molecularly identified as Sporothrix brasiliensis. The final isolate was significantly more virulent in Galleria mellonella larvae compared to earlier isolates. We conclude that S. brasiliensis has the capacity to increase in virulence in vivo. This finding is significant to clinicians caring for individuals with S. brasiliensis disease and it suggests that further studies are needed to identify the mechanisms underlying pathogenicity enhancement during chronic disease.

  8. Aspergillus brasiliensis sp. nov., a biseriate black Aspergillus species with world-wide distribution.

    PubMed

    Varga, János; Kocsubé, Sándor; Tóth, Beáta; Frisvad, Jens C; Perrone, Giancarlo; Susca, Antonia; Meijer, Martin; Samson, Robert A

    2007-08-01

    A novel species, Aspergillus brasiliensis sp. nov., is described within Aspergillus section Nigri. This species can be distinguished from other black aspergilli based on intergenic transcribed region, beta-tubulin and calmodulin gene sequences, by amplified fragment length polymorphism analysis and by extrolite profiles. A. brasiliensis isolates produced naphtho-gamma-pyrones, tensidol A and B and pyrophen in common with Aspergillus niger and Aspergillus tubingensis, but also several unique compounds, justifying their treatment as representing a separate species. None of the isolates were found to produce ochratoxin A, kotanins, funalenone or pyranonigrins. The novel species was most closely related to A. niger, and was isolated from soil from Brazil, Australia, USA and The Netherlands, and from grape berries from Portugal. The type strain of Aspergillus brasiliensis sp. nov. is CBS 101740(T) (=IMI 381727(T)=IBT 21946(T)).

  9. Diversity and antimicrobial potential of culturable heterotrophic bacteria associated with the endemic marine sponge Arenosclera brasiliensis

    PubMed Central

    Rua, Cintia P.J.; Trindade-Silva, Amaro E.; Appolinario, Luciana R.; Venas, Tainá M.; Garcia, Gizele D.; Carvalho, Lucas S.; Lima, Alinne; Kruger, Ricardo; Pereira, Renato C.; Berlinck, Roberto G.S.; Valle, Rogério A.B.; Thompson, Cristiane C.

    2014-01-01

    Marine sponges are the oldest Metazoa, very often presenting a complex microbial consortium. Such is the case of the marine sponge Arenosclera brasiliensis, endemic to Rio de Janeiro State, Brazil. In this investigation we characterized the diversity of some of the culturable heterotrophic bacteria living in association with A. brasiliensis and determined their antimicrobial activity. The genera Endozoicomonas (N = 32), Bacillus (N = 26), Shewanella (N = 17), Pseudovibrio (N = 12), and Ruegeria (N = 8) were dominant among the recovered isolates, corresponding to 97% of all isolates. Approximately one third of the isolates living in association with A. brasiliensis produced antibiotics that inhibited the growth of Bacillus subtilis, suggesting that bacteria associated with this sponge play a role in its health. PMID:25024903

  10. Detection of antibodies against Paracoccidioides brasiliensis melanin in in vitro and in vivo studies during infection.

    PubMed

    Urán, Martha E; Nosanchuk, Joshua D; Restrepo, Angela; Hamilton, Andrew J; Gómez, Beatriz L; Cano, Luz E

    2011-10-01

    Several cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogen Paracoccidioides brasiliensis produces melanin in its conidial and yeast forms. In the present study, melanin particles from P. brasiliensis were injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) κ-chain and four IgM melanin-binding MAbs. The five IgG1 κ-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeled P. brasiliensis conidia and yeast cells both in vitro and in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic and Sepia officinalis melanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin from P. brasiliensis conidia and yeast in sera and bronchoalveolar lavage fluids from P. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin from P. brasiliensis is an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice.

  11. Proteomic Analysis Reveals That Iron Availability Alters the Metabolic Status of the Pathogenic Fungus Paracoccidioides brasiliensis

    PubMed Central

    Parente, Ana F. A.; Bailão, Alexandre M.; Borges, Clayton L.; Parente, Juliana A.; Magalhães, Adriana D.; Ricart, Carlos A. O.; Soares, Célia M. A.

    2011-01-01

    Paracoccidioides brasiliensis is a thermodimorphic fungus and the causative agent of paracoccidioidomycosis (PCM). The ability of P. brasiliensis to uptake nutrients is fundamental for growth, but a reduction in the availability of iron and other nutrients is a host defense mechanism many pathogenic fungi must overcome. Thus, fungal mechanisms that scavenge iron from host may contribute to P. brasiliensis virulence. In order to better understand how P. brasiliensis adapts to iron starvation in the host we compared the two-dimensional (2D) gel protein profile of yeast cells during iron starvation to that of iron rich condition. Protein spots were selected for comparative analysis based on the protein staining intensity as determined by image analysis. A total of 1752 protein spots were selected for comparison, and a total of 274 out of the 1752 protein spots were determined to have changed significantly in abundance due to iron depletion. Ninety six of the 274 proteins were grouped into the following functional categories; energy, metabolism, cell rescue, virulence, cell cycle, protein synthesis, protein fate, transcription, cellular communication, and cell fate. A correlation between protein and transcript levels was also discovered using quantitative RT-PCR analysis from RNA obtained from P. brasiliensis under iron restricting conditions and from yeast cells isolated from infected mouse spleens. In addition, western blot analysis and enzyme activity assays validated the differential regulation of proteins identified by 2-D gel analysis. We observed an increase in glycolytic pathway protein regulation while tricarboxylic acid cycle, glyoxylate and methylcitrate cycles, and electron transport chain proteins decreased in abundance under iron limiting conditions. These data suggest a remodeling of P. brasiliensis metabolism by prioritizing iron independent pathways. PMID:21829521

  12. Conservation genetics of the giant otter (Pteronura brasiliensis (Zimmerman, 1780)) (Carnivora, Mustelidae).

    PubMed

    Garcia, D M; Marmontel, M; Rosas, F W; Santos, F R

    2007-12-01

    The giant otter (Pteronura brasiliensis) is an aquatic mammal of the Mustelidae family, endemic to South America. Its original distribution corresponds to the region from the Guyanas to Central-North Argentina, but it is extinct or on the verge of extinction in most of its historical range. Currently, the species is considered endangered by the World Conservation Union (IUCN). Based on its geographic distribution in the South American continent and on some morphological characters, two subspecies were suggested: P. brasiliensis brasiliensis, occurring in the Amazon and Orinoco River Basins, and P. brasiliensis paranensis, in the Paraná and Paraguai River Basins. However, there is no consensus on assuming this subspecies division and no detailed studies have been carried out to elucidate this question. This study aims to evaluate the genetic diversity and population structure of Pteronura brasiliensis along its range in Brazil to check the possibility of the existence of two distinct subspecies using also a reciprocal monophyly criterion. We analyzed the control region, and the Cytochrome b and Cytochrome c Oxidase subunit I genes of the mitochondrial DNA in several giant otter populations from the Amazon and Paraguai River Basins. Analyses have indicated some degree of geographic correlation and a high level of inter-population divergence, although the subspecies division is not highly supported. As we observed strong population structure, we cannot rule out the existence of further divisions shaping the species distribution. The results suggest that a more complex population structure occurs in P. brasiliensis, and the conservation practice should concentrate on preserving all remaining local populations.

  13. Characterization of Paracoccidioides brasiliensis isolates by random amplified polymorphic DNA analysis.

    PubMed Central

    Soares, C M; Madlun, E E; da Silva, S P; Pereira, M; Felipe, M S

    1995-01-01

    We initially used 25 different random primers in order to test their ability to generate random amplified polymorphic DNA fragments from the dimorphic human pathogenic fungus Paracoccidioides brasiliensis. From the tested primers we chose five to distinguish between seven isolates of this microorganism. The DNA amplification patterns allowed clear differentiation of the seven isolates into two distinct groups with only 35% genomic identity. One of these groups contained two subgroups with 81% genetic similarity. The random amplified polymorphic DNA analysis method proved to be a good tool for analyzing and comparing different genomes of P. brasiliensis isolates. PMID:7714219

  14. Two-dimensional electrophoresis and characterization of antigens from Paracoccidioides brasiliensis.

    PubMed

    da Fonseca, C A; Jesuino, R S; Felipe, M S; Cunha, D A; Brito, W A; Soares, C M

    2001-06-01

    Paracoccidioides brasiliensis is a fungal pathogen of humans. To identify antigens from P. brasiliensis we fractionated a crude preparation of proteins from the fungus and detected the IgG reactive proteins by immunoblot assays of yeast cellular extracts with sera of patients with paracoccidioidomycosis (PCM). We identified and characterized six new antigens by amino acid sequencing and homology search analyses with other proteins deposited in a database. The newly characterized antigens were highly homologous to catalase, fructose-1,6-biphosphate aldolase (aldolase), glyceraldehyde-3-phosphate dehydrogenase, malate dehydrogenase and triosephosphate isomerase from several sources. The characterized antigens presented preferential synthesis in yeast cells, the host fungus phase.

  15. TLR9 Activation Dampens the Early Inflammatory Response to Paracoccidioides brasiliensis, Impacting Host Survival

    PubMed Central

    Menino, João Filipe; Saraiva, Margarida; Gomes-Alves, Ana G.; Lobo-Silva, Diogo; Sturme, Mark; Gomes-Rezende, Jéssica; Saraiva, Ana Laura; Goldman, Gustavo H.; Cunha, Cristina; Carvalho, Agostinho; Romani, Luigina; Pedrosa, Jorge; Castro, António Gil; Rodrigues, Fernando

    2013-01-01

    Background Paracoccidioides brasiliensis causes paracoccidioidomycosis, one of the most prevalent systemic mycosis in Latin America. Thus, understanding the characteristics of the protective immune response to P. brasiliensis is of interest, as it may reveal targets for disease control. The initiation of the immune response relies on the activation of pattern recognition receptors, among which are TLRs. Both TLR2 and TLR4 have been implicated in the recognition of P. brasiliensis and regulation of the immune response. However, the role of TLR9 during the infection by this fungus remains unclear. Methodology/Principal findings We used in vitro and in vivo models of infection by P. brasiliensis, comparing wild type and TLR9 deficient (−/−) mice, to assess the contribution of TLR9 on cytokine induction, phagocytosis and outcome of infection. We show that TLR9 recognizes either the yeast form or DNA from P. brasiliensis by stimulating the expression/production of pro-inflammatory cytokines by bone marrow derived macrophages, also increasing their phagocytic ability. We further show that TLR9 plays a protective role early after intravenous infection with P. brasiliensis, as infected TLR9−/− mice died at higher rate during the first 48 hours post infection than wild type mice. Moreover, TLR9−/− mice presented tissue damage and increased expression of several cytokines, such as TNF-α and IL-6. The increased pattern of cytokine expression was also observed during intraperitoneal infection of TLR9−/− mice, with enhanced recruitment of neutrophils. The phenotype of TLR9−/− hosts observed during the early stages of P. brasiliensis infection was reverted upon a transient, 48 hours post-infection, neutrophil depletion. Conclusions/Significance Our results suggest that TLR9 activation plays an early protective role against P. brasiliensis, by avoiding a deregulated type of inflammatory response associated to neutrophils that may lead to tissue damage. Thus

  16. Therapeutic Effect of Agaricus brasiliensis on Phenylhydrazine-Induced Neonatal Jaundice in Rats

    PubMed Central

    Zhang, Lan; Yuan, Bo; Wang, HuiPing; Gao, Ya

    2015-01-01

    The present study was designed to investigate the effect of Agaricus brasiliensis extract (ABE) on phenylhydrazine-induced neonatal jaundice in rats. Administration of ABE dose-dependently reduced the elevated bilirubin level induced by phenylhydrazine. It can be somewhat supported from the results of in vitro bilirubin degradation experiment. ABE treatment also reduced the total antioxidant status (TAOS), cascade O2−/SOD, level of NF-κB protein, and adrenomedullin (AM). Overall, the results of this study demonstrated that Agaricus brasiliensis extract may be beneficial to reducing bilirubin level without causing hepatotoxicity in neonatal jaundice. PMID:25883968

  17. New method for estimating digestion of Paracoccidioides brasiliensis by phagocytic cells in vitro.

    PubMed Central

    Goihman-Yahr, M; Essenfeld-Yahr, E; Albornoz, M C; Yarzábal, L; de Gómez, M H; San Martín, B; Ocanto, A; Convit, J

    1979-01-01

    We describe a method by which phagocytosis and digestion of Paracoccidioides brasiliensis yeast cells by polymorphonuclear leukocytes or other phagocytic cells may be estimated. Suspensions of P. brasiliensis in its yeastlike phase were sonicated, counted, and incubated with known numbers of peripheral blood polymorphonuclear leukocytes. At given intervals, cytocentrifuge droplets were stained by a variation of Papanicolaou's method. Stained preparations were examined with phase-contrast optics. Digested organisms showed total or partial disappearance of protoplasm. Green-stained cell walls resisted digestion. The proportion of digested cells as a function of time was estimated. Images PMID:90683

  18. Immunomodulating Activity of Agaricus brasiliensis KA21 in Mice and in Human Volunteers

    PubMed Central

    Fukuwatari, Yasushi; Okumura, Ko; Takeda, Kazuyoshi; Ishibashi, Ken-ichi; Furukawa, Mai; Ohno, Naohito; Mori, Kazu; Gao, Ming; Motoi, Masuro

    2008-01-01

    We performed studies on murine models and human volunteers to examine the immunoenhancing effects of the naturally outdoor-cultivated fruit body of Agaricus brasiliensis KA21 (i.e. Agaricus blazei). Antitumor, leukocyte-enhancing, hepatopathy-alleviating and endotoxin shock-alleviating effects were found in mice. In the human study, percentage body fat, percentage visceral fat, blood cholesterol level and blood glucose level were decreased, and natural killer cell activity was increased. Taken together, the results strongly suggest that the A. brasiliensis fruit body is useful as a health-promoting food. PMID:18604247

  19. Nuclear transfer and cloning.

    PubMed

    Wolf, D P

    2001-10-01

    The use of nuclear transfer in human reproductive and therapeutic cloning is reviewed with attention on the origins of this technology from its evolution to the present. The successes and limitations of mammalian reproductive cloning are itemized. A case is made against the use of human reproductive cloning to reproduce an existing person, based on the unacceptable risks to the embryo, fetus, or newborn. However, support is extended for human therapeutic cloning involving the derivation and use of embryonic stem cells to treat human disease.

  20. [Cloning--ethical aspects].

    PubMed

    Munzarová, M

    2004-01-01

    Ethical problems related to cloning are discussed on three model situations: cloning of human beings (for example by utilizing the techniques of embryo splitting or nuclear transfer), use of embryonic cells in cloning techniques and cloning of nonembryonic cells. The first situation is strictly condemned, the second has been examined up present (it should be condemned as well) and the third is--under certain conditions--fully acceptable. The issue is discussed from the point of view of relevant Council of Europe documents as well.

  1. Production of Paracoccidioides brasiliensis exoantigens for immunodiffusion tests.

    PubMed Central

    De Camargo, Z; Unterkircher, C; Campoy, S P; Travassos, L R

    1988-01-01

    Growth curves of the yeast form of Paracoccidioides brasiliensis B-339 based on total and viable cell counts were determined. Crude culture filtrate antigens were obtained after 7, 10, 15, 20, 25, and 30 days of incubation. Different patterns of proteins were obtained by affinity chromatography on Sepharose 4B-immunoglobulin G complex made with immunoglobulin G from patients with paracoccidioidomycosis, with subsequent analyses by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and scanning densitometry. Three major proteins were excreted during the time course of a 30-day culture: a doublet at 20 to 21 kilodaltons (kDa) and molecules of 43 and 52 kDa. The 43-kDa antigen was present throughout the growth period, and its level reached a peak on days 15 to 20 and then decreased considerably toward day 30. The antigenic preparations collected on days 7, 10, 15, and 20 gave better reactions in immunodiffusion tests than those collected on days 25 and 30. The 7-day exoantigen gave a sensitivity of 97.1% and specificity of 100% on immunodiffusion. The main line of precipitation had a very high intensity, showing a total identity with that of a previously purified glycoprotein of 43 kDa. A 7-day crude exoantigen displayed a high level of sensitivity and specificity, being reproducible from batch to batch and retaining its activity for years when kept lyophilized. A protocol is recommended for the production of a stable diagnostic antigen to be used in immunodiffusion tests for paracoccidioidomycosis. Images PMID:3141460

  2. Susceptibility of Sporothrix brasiliensis isolates to amphotericin B, azoles, and terbinafine.

    PubMed

    Borba-Santos, Luana Pereira; Rodrigues, Anderson Messias; Gagini, Thalita Braga; Fernandes, Geisa Ferreira; Castro, Rafaela; de Camargo, Zoilo Pires; Nucci, Marcio; Lopes-Bezerra, Leila Maria; Ishida, Kelly; Rozental, Sonia

    2015-02-01

    The in vitro activity of the antifungal agents amphotericin B (AMB), itraconazole (ITC), posaconazole (PSC), voriconazole (VRC), and terbinafine (TRB) against 32 Brazilian isolates of Sporothrix brasiliensis, including 16 isolates from a recent (2011-2012) epidemic in Rio de Janeiro state, was examined. We describe and genotype new isolates and clustered them with 16 older (from 2004 or earlier) S. brasiliensis isolates by phylogenetic analysis. We tested both the yeast and the mycelium form of all isolates using broth microdilution methods based on the reference protocols M38-A2 and M27-A3 (recommended by the Clinical and Laboratory Standards Institute). Considering minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs), TRB was found to be the most active drug in vitro for both fungal forms, followed by PSC. Several isolates showed high MICs for AMB and/or ITC, which are currently used as first-line therapy for sporotrichosis. VRC displayed very low activity against S. brasiliensis isolates. The primary morphological modification observed on treated yeasts by transmission electron microscopy analysis was changes in cell wall. Our results indicate that TRB is the antifungal with the best in vitro activity against S. brasiliensis and support the use of TRB as a promising option for the treatment of cutaneous and/or lymphocutaneous sporotrichosis.

  3. Decreased expression of 14-3-3 in Paracoccidioides brasiliensis confirms its involvement in fungal pathogenesis

    PubMed Central

    Marcos, Caroline Maria; da Silva, Julhiany de Fátima; de Oliveira, Haroldo Cesar; Assato, Patrícia Akemi; Singulani, Junya de Lacorte; Lopez, Angela Maria; Tamayo, Diana Patricia; Hernandez-Ruiz, Orville; McEwen, Juan G; Mendes-Giannini, Maria José Soares; Fusco-Almeida, Ana Marisa

    2016-01-01

    The interaction between the fungal pathogen Paracoccidioides brasiliensis and host cells is usually mediated by specific binding events between adhesins on the fungal surface and receptors on the host extracellular matrix or cell surface. One molecule implicated in the P. brasiliensis-host interaction is the 14-3-3 protein. The 14-3-3 protein belongs to a family of conserved regulatory molecules that are expressed in all eukaryotic cells and are involved in diverse cellular functions. Here, we investigated the relevance of the 14-3-3 protein to the virulence of P. brasiliensis. Using antisense RNA technology and Agrobacterium tumefaciens-mediated transformation, we generated a 14-3-3-silenced strain (expression reduced by ˜55%). This strain allowed us to investigate the interaction between 14-3-3 and the host and to correlate the functions of P. brasiliensis 14-3-3 with cellular features, such as morphological characteristics and virulence, that are important for pathogenesis. PMID:26646480

  4. Wild animals as sentinels of Paracoccidioides brasiliensis in the state of Rio Grande do Sul, Brazil.

    PubMed

    Albano, A P N; Klafke, G B; Brandolt, T M; Da Hora, V P; Minello, L F; Jorge, S; Santos, E O; Behling, G M; Camargo, Z P; Xavier, M O; Meireles, M C A

    2014-04-01

    Paracoccidioides brasiliensis, a dimorphic pathogenic fungus, causes the principal form of systemic mycosis in Brazil. The literature furnishes only limited data on the ecology of this fungus in the state of Rio Grande do Sul, the southernmost state of Brazil. The purpose of this study was to evaluate the prevalence of fungal infection in wild animals, using serological tests and using the animals as sentinels of the presence of P. brasiliensis in three specified mesoregions of Rio Grande do Sul. A total of 128 wild animals from the three mesoregions were included in the study. The serum samples were evaluated by immunodiffusion and the enzyme-linked immunosorbent assay (ELISA) technique to detect anti-gp43 antibodies from P. brasiliensis. Two conjugates were tested and compared with the ELISA technique. Although no positive samples were detected by immunodiffusion, 26 animals (20%), belonging to 13 distinct species, were found to be seropositive by the ELISA technique. The seropositive animals were from two mesoregions of the state. The results were similar according to the gender, age, and family of the animals, but differed significantly according to the conjugate used (p < 0.001), showing more sensitivity to protein A-peroxidase than to protein G-peroxidase. The finding that wild animals from the state of Rio Grande do Sul are exposed to P. brasiliensis suggests that the fungus can be found in this region despite the often-rigorous winters, which frequently include below-freezing temperatures.

  5. Vaccination of mice with liposome-entrapped adult antigens of Nippostrongylus brasiliensis.

    PubMed

    Rhalem, A; Bourdieu, C; Luffau, G; Pery, P

    1988-01-01

    An immunization procedure was developed to induce protection of mice against the gastrointestinal helminth Nippostrongylus brasiliensis. Mice immunized by the oral route with antigens which were released by adult worms during their in vitro survival in a detergent-containing medium and which were entrapped in liposomes were protected against a challenge infection.

  6. A Novel Anelloviridae Species Detected in Tadarida brasiliensis Bats: First Sequence of a Chiropteran Anellovirus

    PubMed Central

    Cibulski, Samuel Paulo; Teixeira, Thais Fumaco; de Sales Lima, Francisco Esmaile; do Santos, Helton Fernandes; Franco, Ana Claudia

    2014-01-01

    Using metagenomic approaches, we identified a novel Torque teno virus from Brazilian free-tailed bats (Tadarida brasiliensis) (TT-TbV). The TT-TbV genome and deduced protein sequences share extremely low identity with known anelloviruses. Due to a high degree of phylogenetic divergence, such putative virus could not be allocated into any Anelloviridae genera. PMID:25359906

  7. Psychophysical frequency modulation thresholds in a FM-bat, Tadarida brasiliensis.

    PubMed

    Bartsch, E; Schmidt, S

    1993-05-01

    Echolocating bats hunting flying insects discriminate complex temporal patterns of acoustic stimuli. For bats using frequency modulated sonar calls (FM bats), there are no behavioral data on the perception of sinusoidally frequency modulated (SFM) stimuli. Discrimination performance for SFM stimuli of varying modulation depth was measured in 4 Tadarida brasiliensis in a two-alternative, forced choice procedure. A center frequency of 40 kHz was modulated with rates between 10 and 2000 Hz. It was found that discrimination performance improved from a mean threshold modulation depth of 3.05 kHz at a modulation rate of 2000 Hz to 1.58 kHz at a modulation rate of 10 Hz. Psychoacoustical modulation depth thresholds of T. brasiliensis are thus distinctly larger than those observed in bat species emitting constant frequency (CF) components followed by an FM-sweep, in active echolocation experiments. The modulation thresholds of T. brasiliensis are discussed in connection with the ability of bats to discriminate insect wingbeats. A comparison between non-echolocating mammals and the FM bat T. brasiliensis shows that the ability to echolocate is not reflected in the modulation thresholds.

  8. A Novel Anelloviridae Species Detected in Tadarida brasiliensis Bats: First Sequence of a Chiropteran Anellovirus.

    PubMed

    Cibulski, Samuel Paulo; Teixeira, Thais Fumaco; de Sales Lima, Francisco Esmaile; do Santos, Helton Fernandes; Franco, Ana Claudia; Roehe, Paulo Michel

    2014-10-30

    Using metagenomic approaches, we identified a novel Torque teno virus from Brazilian free-tailed bats (Tadarida brasiliensis) (TT-TbV). The TT-TbV genome and deduced protein sequences share extremely low identity with known anelloviruses. Due to a high degree of phylogenetic divergence, such putative virus could not be allocated into any Anelloviridae genera.

  9. Inhibition of growth of the dimorphic fungus Paracoccidioides brasiliensis by ajoene.

    PubMed Central

    San-Blas, G; San-Blas, F; Gil, F; Mariño, L; Apitz-Castro, R

    1989-01-01

    Ajoene, a garlic-derived compound that prevents platelet activation, inhibited the growth of Paracoccidioides brasiliensis, a fungal pathogen for humans, by affecting the integrity of the fungal cytoplasmic membrane. This action may be the basis for the study of ajoene as a possible specific antifungal drug. Images PMID:2817865

  10. Immunological characterization of a recombinant 27-kilodalton antigenic protein from Paracoccidioides brasiliensis.

    PubMed

    Ortiz, B L; Garcia, A M; Restrepo, A; McEwen, J G

    1996-03-01

    We report the expression in Escherichia coli of a 27-kDa antigenic protein from Paracoccidioides brasiliensis. When analyzed by immunoblotting, this recombinant antigenic protein was recognized by antibodies present in the sera of 40 of the 44 paracoccidioidomycosis patients studied. No cross-reactions were observed with sera from patients with other mycoses (histoplasmosis, aspergillosis, cryptococcosis, sporotrichosis, and chromoblastomycosis) or with tuberculosis.

  11. Paracoccidioides brasiliensis Interferes on Dendritic Cells Maturation by Inhibiting PGE2 Production

    PubMed Central

    2015-01-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in most Latin American countries, especially in Brazil, whose etiologic agent is the thermodimorphic fungus of the genus Paracoccidioides, comprising cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii. The mechanisms involved in the initial interaction of the fungus with cells of the innate immune response, as dendritic cells (DCs), deserve to be studied. Prostaglandins (PGs) are eicosanoids that play an important role in modulating functions of immune cells including DCs. Here we found that human immature DCs derived from the differentiation of monocytes cultured with GM-CSF and IL-4 release substantial concentrations of PGE2, which, however, were significantly inhibited after challenge with P. brasiliensis. In vitro blocking of pattern recognition receptors (PRRs) by monoclonal antibodies showed the involvement of mannose receptor (MR) in PGE2 inhibition by the fungus. In addition, phenotyping assays showed that after challenge with the fungus, DCs do not change their phenotype of immature cells to mature ones, as well as do not produce IL-12 p70 or adequate concentrations of TNF-α. Assays using exogenous PGE2 confirmed an association between PGE2 inhibition and failure of cells to phenotypically mature in response to P. brasiliensis. We conclude that a P. brasiliensis evasion mechanism exists associated to a dysregulation on DC maturation. These findings may provide novel information for the understanding of the complex interplay between the host and this fungus. PMID:25793979

  12. A secreted serine protease of Paracoccidioides brasiliensis and its interactions with fungal proteins

    PubMed Central

    2010-01-01

    Background Paracoccidioides brasiliensis is a thermodimorphic fungus, the causative agent of paracoccidioidomycosis (PCM). Serine proteases are widely distributed and this class of peptidase has been related to pathogenesis and nitrogen starvation in pathogenic fungi. Results A cDNA (Pbsp) encoding a secreted serine protease (PbSP), was isolated from a cDNA library constructed with RNAs of fungal yeast cells recovered from liver of infected mice. Recombinant PbSP was produced in Escherichia coli, and used to develop polyclonal antibodies that were able to detect a 66 kDa protein in the P. brasiliensis proteome. In vitro deglycosylation assays with endoglycosidase H demonstrated that PbSP is a N-glycosylated molecule. The Pbsp transcript and the protein were induced during nitrogen starvation. The Pbsp transcript was also induced in yeast cells infecting murine macrophages. Interactions of PbSP with P. brasiliensis proteins were evaluated by two-hybrid assay in the yeast Saccharomyces cerevisiae. PbSP interacts with a peptidyl prolyl cis-trans isomerase, calnexin, HSP70 and a cell wall protein PWP2. Conclusions A secreted subtilisin induced during nitrogen starvation was characterized indicating the possible role of this protein in the nitrogen acquisition. PbSP interactions with other P. brasiliensis proteins were reported. Proteins interacting with PbSP are related to folding process, protein trafficking and cytoskeleton reorganization. PMID:21080956

  13. A Morphological and Cytochemical Study of the Interaction between Paracoccidiodes brasiliensis and Neutrophils

    NASA Astrophysics Data System (ADS)

    Dias, Maria Fernanda R. G.; Filgueira, Absalom L.; de Souza, Wanderley

    2004-04-01

    Paracoccidioidomycosis is a systemic granulomatous disease caused by the dimorphic fungus Paracoccidioides brasiliensis. It is the most prevalent systemic mycosis of Latin America and 80% of the reported cases are from Brazil. Because of the great number of neutrophils found in the P. brasiliensis granuloma, studies have been done to evaluate the role of these cells during the development of the infection. Scanning and transmission electron microscopy of thin sections showed that the neutrophils ingest yeast cells through a typical phagocytic process with the formation of pseudopodes. The pseudopodes even disrupt the connection established between the mother and the bud cells. Neutrophils also associate to each other, forming a kind of extracellular vacuole where large yeast cells are encapsulated. Cytochemical studies showed that once P. brasiliensis attaches to the neutrophil surface, it triggers a respiratory burst with release of oxygen-derived products. Attachment also triggers neutrophils' degranulation, with release of endogenous peroxidase localized in cytoplasmic granules. Together, these processes lead to killing of both ingested and extracellular P. brasiliensis.

  14. Cell-free antigens of Sporothrix brasiliensis: antigenic diversity and application in an immunoblot assay.

    PubMed

    Almeida-Paes, Rodrigo; Bailão, Alexandre Melo; Pizzini, Cláudia Vera; Reis, Rosani Santos; Soares, Célia Maria de Almeida; Peralta, José Mauro; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely Maria

    2012-11-01

    Sporotrichosis is a subcutaneous mycosis diagnosed by isolation of the fungus in culture. Serological tests for help in diagnosis in general do not use purified or recombinant antigens, because there is a paucity of described immunoreactive proteins, especially for the new described Sporothrix species, such as Sporothrix brasiliensis. This study aims to characterise antigens from S. brasiliensis and verify their application in serodiagnosis of sporotrichosis. An immunoblot assay allied with computer-based analysis was used to identify putative antigenic molecules in a cell-free extracts of both morphological phases of this fungus, and to delineate antigenic polymorphism among seven S. brasiliensis isolates and one S. schenckii Brazilian strain. The mycelial and yeast phase of the fungus originated 14 and 23 reactive bands, respectively, which were variable in intensity. An 85 kDa antigen, verified in the yeast phase of the fungus, was observed in all strains used and the immunodominant protein was identified. This protein, however, cross-react with serum samples from patients infected with other pathogens. The results show that the S. brasiliensis cell-free antigen extract is a single and inexpensive source of antigens, and can be applied on the sporotrichosis serodiagnosis.

  15. Comparison of various techniques for determining viability of Paracoccidioides brasiliensis yeast-form cells.

    PubMed Central

    Restrepo, A; Cano, L E; de Bedout, C; Brummer, E; Stevens, D A

    1982-01-01

    The viability of Paracoccidioides brasiliensis yeast-form cells was determined by colony-forming units, direct fluorescent staining, and production of germ tubes in slide culture. The first procedure was unreliable and time consuming; the latter two showed better correlation with hemacytometer total cell counts and required significantly less time. PMID:7107858

  16. Activation of the alternative complement pathway in canine normal serum by Paracoccidioides brasiliensis

    PubMed Central

    Bianchini, A.A.C.; Petroni, T.F.; Fedatto, P.F.; Bianchini, R.R.; Venancio, E.J.; Itano, E.N.; Ono, M.A.

    2009-01-01

    The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a human granulomatous disease. Recently the first case of natural disease in dogs was reported. The complement system is an important effector component of humoral immunity against infectious agents. Therefore, the aim of this study was to evaluate the activation of the dog alternative complement pathway by P. brasiliensis. Initially, the ability of erythrocytes of guinea pig, rabbit, sheep, chicken and swine to activate the dog alternative pathway was evaluated. The guinea pig erythrocytes showed the greatest capacity to activate dog alternative pathway. The alternative (AH50) hemolytic activity was evaluated in 27 serum samples from healthy dogs and the mean values were 87.2 AH50/ml. No significant differences were observed in relation to sex and age. The alternative pathway activation by P. brasiliensis was higher in serum samples from adult dogs when compared to puppies and aged dogs (p ≤ 0.05). This is the first report of dog alternative complement pathway activation by P. brasiliensis and suggests that it may play a protective role in canine paracoccidioidomycosis. PMID:24031350

  17. Oxidative stress response in Paracoccidioides brasiliensis: assessing catalase and cytochrome c peroxidase.

    PubMed

    Dantas, Alessandra S; Andrade, Rosângela V; de Carvalho, Maria J; Felipe, Maria Sueli S; Campos, Elida G

    2008-06-01

    Paracoccidioides brasiliensis is a dimorphic fungus that infects humans and establishes infection in the yeast form. We are interested in the mechanisms this fungus uses to evade the human immune system, and in its survival strategies within infected host cells. Reactive oxygen species play an important role in host defence, but are detoxified by pathogen-derived antioxidant enzymes to prevent oxidative damage. The transcriptional and post-transcriptional regulation of P. brasiliensis catalase and cytochrome-c peroxidase (CCP) antioxidant enzymes upon culture treatment with hydrogen peroxide (H(2)O(2)) is described. High H(2)O(2) concentrations (up to 100 mm) still permitted 70-100% survival of exponential and stationary phase yeast cells, though stationary phase cells were consistently more resistant. P. brasiliensis has both cytosolic and peroxisomal catalase isoenzymes and a single cytochrome-c peroxidase. High-dose treatments with H(2)O(2) led to an early increase in total catalase and CCP enzymatic activities, indicative of post-transcriptional regulation. The expression levels of the catalase genes increased three to fourfold when the cells were treated with 50 mm H(2)O(2) for 40 or 50 min. Lipid peroxidation, as assessed by the thiobarbituric acid method, was relatively low upon treatment with H(2)O(2), which was consistent with our results demonstrating that P. brasiliensis has a powerful antioxidant defence system enabling it to survive H(2)O(2)-mediated stress.

  18. Genetic differentiation of Ganaspis brasiliensis (Hymenoptera: Figitidae) from East and Southeast Asia

    USDA-ARS?s Scientific Manuscript database

    This study aims to clarify genetic differentiation of the Drosophila parasitoid Ganaspis brasiliensis (Hymenoptera; Figitidae; Eucoilinae) based on the nucleotide sequences of the cytochrome oxidase subunit 1 (CO1) and three nuclear DNA regions, the inter-transcribed spacers 1 and 2 (ITS1 and ITS2) ...

  19. Molecular detection of Paracoccidioides brasiliensis in road-killed wild animals.

    PubMed

    Richini-Pereira, Virgínia Bodelão; Bosco, Sandra de Moraes Gimenes; Griese, Juliana; Theodoro, Raquel Cordeiro; Macoris, Severino Assis Graça; da Silva, Reinaldo José; Barrozo, Lígia; Tavares, Patrícia Morais e Silva; Zancopé-Oliveira, Rosely Maria; Bagagli, Eduardo

    2008-02-01

    Paracoccidioides brasiliensis infections have been little studied in wild and/or domestic animals, which may represent an important indicator of the presence of the pathogen in nature. Road-killed wild animals have been used for surveillance of vectors of zoonotic pathogens and may offer new opportunities for eco-epidemiological studies of paracoccidiodomycosis (PCM). The presence of P. brasiliensis infection was evaluated by Nested-PCR in tissue samples collected from 19 road-killed animals; 3 Cavia aperea (guinea pig), 5 Cerdocyon thous (crab-eating-fox), 1 Dasypus novemcinctus (nine-banded armadillo), 1 Dasypus septemcinctus (seven-banded armadillo), 2 Didelphis albiventris (white-eared opossum), 1 Eira barbara (tayra), 2 Gallictis vittata (grison), 2 Procyon cancrivorus (raccoon) and 2 Sphiggurus spinosus (porcupine). Specific P. brasiliensis amplicons were detected in (a) several organs of the two armadillos and one guinea pig, (b) the lung and liver of the porcupine, and (c) the lungs of raccoons and grisons. P. brasiliensis infection in wild animals from endemic areas might be more common than initially postulated. Molecular techniques can be used for detecting new hosts and mapping 'hot spot' areas of PCM.

  20. Non-Coding RNAs are Differentially Expressed by Nocardia brasiliensis in Vitro and in Experimental Actinomycetoma.

    PubMed

    Cruz-Rabadán, Josué S; Miranda-Ríos, Juan; Espín-Ocampo, Guadalupe; Méndez-Tovar, Luis J; Maya-Pineda, Héctor Rubén; Hernández-Hernández, Francisca

    2017-01-01

    Nocardia spp. are common soil-inhabiting bacteria that frequently infect humans through traumatic injuries or inhalation routes and cause infections, such as actinomycetoma and nocardiosis, respectively. Nocardia brasiliensis is the main aetiological agent of actinomycetoma in various countries. Many bacterial non-coding RNAs are regulators of genes associated with virulence factors. The aim of this work was to identify non-coding RNAs (ncRNAs) expressed during infection conditions and in free-living form (in vitro) in Nocardia brasiliensis. The N. brasiliensis transcriptome (predominately < 200 nucleotides) was determined by RNA next-generation sequencing in both conditions. A total of seventy ncRNAs were identified in both conditions. Among these ncRNAs, 18 were differentially expressed, 12 were located within intergenic regions, and 2 were encoded as antisense of 2 different genes. Finally, 10 of these ncRNAs were studied by rapid amplification of cDNA ends and/or quantitative reverse transcription polymerase chain reaction. Interestingly, 3 transcripts corresponded to tRNA-derived fragments (tRNAs(Cys, Met, Thr)), and one transcript was overlapped between an intergenic region and the 5´end of the 23S rRNA. Expression of these last four transcripts was increased during N. brasiliensis infection compared with the in vitro conditions. The results of this work suggest a possible role for these transcripts in the regulation of virulence genes in actinomycetoma pathogenesis.

  1. Ecological study of Paracoccidioides brasiliensis in soil: growth ability, conidia production and molecular detection

    PubMed Central

    Terçarioli, Gisela Ramos; Bagagli, Eduardo; Reis, Gabriela Martins; Theodoro, Raquel Cordeiro; Bosco, Sandra De Moraes Gimenes; Macoris, Severino Assis da Graça; Richini-Pereira, Virgínia Bodelão

    2007-01-01

    Background Paracoccidioides brasiliensis ecology is not completely understood, although several pieces of evidence point to the soil as its most probable habitat. The present study aimed to investigate the fungal growth, conidia production and molecular pathogen detection in different soil conditions. Methods Soils samples of clayey, sandy and medium textures were collected from ground surface and the interior of armadillo burrows in a hyperendemic area of Paracoccidioidomycosis. P. brasiliensis was inoculated in soil with controlled humidity and in culture medium containing soil extracts. The molecular detection was carried out by Nested PCR, using panfungal and species specific primers from the ITS-5.8S rDNA region. Results The soil texture does not affect fungus development and the growth is more abundant on/in soil saturated with water. Some soil samples inhibited the development of P. brasiliensis, especially those that contain high values of Exchangeable Aluminum (H+Al) in their composition. Some isolates produced a large number of conidia, mainly in soil-extract agar medium. The molecular detection was positive only in samples collected from armadillo burrows, both in sandy and clayey soil. Conclusion P. brasiliensis may grow and produce the infectious conidia in sandy and clayey soil, containing high water content, mainly in wild animal burrows, but without high values of H+Al. PMID:17953742

  2. Pulmonary cavitation and skin lesions mimicking tuberculosis in a HIV negative patient caused by Sporothrix brasiliensis

    PubMed Central

    Orofino-Costa, Rosane; Unterstell, Natasha; Carlos Gripp, Alexandre; de Macedo, Priscila Marques; Brota, Arles; Dias, Emylli; de Melo Teixeira, Marcus; Felipe, Maria Sueli; Bernardes-Engemann, Andréa R; Lopes-Bezerra, Leila Maria

    2013-01-01

    A 32-year-old HIV negative male presented with multiple pulmonary cavitation and skin abscesses up to 15 cm in diameter mimicking tuberculosis. Sporothrix brasiliensis was isolated and patient responded well to amphotericin B followed by itraconazole, except the skin lesions that had to be surgical drained to obtain cure. PMID:24432220

  3. IL-4Rα-Associated Antigen Processing by B Cells Promotes Immunity in Nippostrongylus brasiliensis Infection

    PubMed Central

    Hoving, Jennifer C.; Nieuwenhuizen, Natalie; McSorley, Henry J.; Ndlovu, Hlumani; Bobat, Saeeda; Kimberg, Matti; Kirstein, Frank; Cutler, Anthony J.; DeWals, Benjamin; Cunningham, Adam F.; Brombacher, Frank

    2013-01-01

    In this study, B cell function in protective TH2 immunity against N. brasiliensis infection was investigated. Protection against secondary infection depended on IL-4Rα and IL-13; but not IL-4. Protection did not associate with parasite specific antibody responses. Re-infection of B cell-specific IL-4Rα−/− mice resulted in increased worm burdens compared to control mice, despite their equivalent capacity to control primary infection. Impaired protection correlated with reduced lymphocyte IL-13 production and B cell MHC class II and CD86 surface expression. Adoptive transfer of in vivo N. brasiliensis primed IL-4Rα expressing B cells into naïve BALB/c mice, but not IL-4Rα or IL-13 deficient B cells, conferred protection against primary N. brasiliensis infection. This protection required MHC class II compatibility on B cells suggesting cognate interactions by B cells with CD4+ T cells were important to co-ordinate immunity. Furthermore, the rapid nature of these protective effects by B cells suggested non-BCR mediated mechanisms, such as via Toll Like Receptors, was involved, and this was supported by transfer experiments using antigen pulsed Myd88−/− B cells. These data suggest TLR dependent antigen processing by IL-4Rα-responsive B cells producing IL-13 contribute significantly to CD4+ T cell-mediated protective immunity against N. brasiliensis infection. PMID:24204255

  4. IL-13 receptor alpha-2 regulates the immune and functional response to Nippostrongylus brasiliensis infection

    USDA-ARS?s Scientific Manuscript database

    IL-13 has a prominent role in host defense against the gastrointestinal nematode, Nippostrongylus brasiliensis; however, the role of IL-13 alpha2 in the immune and functional response to enteric infection is not known. In the current study, we investigated changes in smooth muscle and epithelial ce...

  5. Cell signaling pathways in Paracoccidioides brasiliensis--inferred from comparisons with other fungi.

    PubMed

    Fernandes, Larissa; Araújo, Marcus A M; Amaral, André; Reis, Viviane Castelo Branco; Martins, Natália F; Felipe, M S

    2005-06-30

    The human fungal pathogen Paracoccidioides brasiliensis is an ascomycete that displays a temperature-dependent dimorphic transition, appearing as a mycelium at 22 degrees C and as a yeast at 37 degrees C, this latter being the virulent form. We report on the in silico search made of the P. brasiliensis transcriptome-expressed sequence tag database for components of signaling pathways previously known to be involved in morphogenesis and virulence in other species of fungi, including Saccharomyces cerevisiae, Cryptococcus neoformans, Candida albicans, and Aspergillus fumigatus. Using this approach, it was possible to identify several protein cascades in P. brasiliensis, such as i) mitogen-activated protein kinase signaling for cell integrity, cell wall construction, pheromone/mating, and osmo-regulation, ii) the cAMP/PKA system, which regulates fungal development and virulence, iii) the Ras protein, which allows cross-talking between cascades, iv) calcium-calmodulin-calcineurin, which controls cell survival under oxidative stress, high temperature, and membrane/cell wall perturbation, and v) the target of rapamycin pathway, controlling cell growth and proliferation. The ways in which P. brasiliensis responds to the environment and modulates the expression of genes required for its survival and virulence can be inferred through comparison with other fungi for which this type of data is already available.

  6. Minimal inhibitory concentration distributions and epidemiological cutoff values of five antifungal agents against Sporothrix brasiliensis.

    PubMed

    Almeida-Paes, Rodrigo; Brito-Santos, Fábio; Figueiredo-Carvalho, Maria Helena Galdino; Machado, Ana Caroline Sá; Oliveira, Manoel Marques Evangelista; Pereira, Sandro Antonio; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely Maria

    2017-05-01

    Sporothrix brasiliensis is the most virulent sporotrichosis agent. This species usually responds to antifungal drugs, but therapeutic failure can occur in some patients. Antifungal susceptibility tests have been performed on this species, but no clinical breakpoints (CBPs) are available. In this situation, minimal inhibitory concentration (MIC) distributions and epidemiological cutoff values (ECVs) support the detection of identification of resistant strains. To study the MIC distributions of five antifungal drugs against S. brasiliensis and to propose tentative ECVs. MICs of amphotericin B (AMB), itraconazole (ITR), ketoconazole (KET), posaconazole (POS), and terbinafine (TRB) against 335 S. brasiliensis strains were determined by the Clinical and Laboratory Standards Institute broth microdilution method. The proposed ECV, in µg/mL, for AMB, ITR, KET, POS, and TRB were 4.0, 2.0, 1.0, 2.0, and 0.25, respectively. Percentages of wild-type strains in our population for the above antifungal drugs were 98.48, 95.22, 95.33, 100, and 97.67%, respectively. These ECVs will be useful to detect strains with resistance, to define CBPs, and to elaborate specific therapeutic guidelines for S. brasiliensis. Rational use of antifungals is strongly recommended to avoid the emergence of resistant strains and ensure the therapeutic effectiveness of sporotrichosis.

  7. Minimal inhibitory concentration distributions and epidemiological cutoff values of five antifungal agents against Sporothrix brasiliensis

    PubMed Central

    Almeida-Paes, Rodrigo; Brito-Santos, Fábio; Figueiredo-Carvalho, Maria Helena Galdino; Machado, Ana Caroline Sá; Oliveira, Manoel Marques Evangelista; Pereira, Sandro Antonio; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely Maria

    2017-01-01

    BACKGROUND Sporothrix brasiliensis is the most virulent sporotrichosis agent. This species usually responds to antifungal drugs, but therapeutic failure can occur in some patients. Antifungal susceptibility tests have been performed on this species, but no clinical breakpoints (CBPs) are available. In this situation, minimal inhibitory concentration (MIC) distributions and epidemiological cutoff values (ECVs) support the detection of identification of resistant strains. OBJECTIVES To study the MIC distributions of five antifungal drugs against S. brasiliensis and to propose tentative ECVs. METHODS MICs of amphotericin B (AMB), itraconazole (ITR), ketoconazole (KET), posaconazole (POS), and terbinafine (TRB) against 335 S. brasiliensis strains were determined by the Clinical and Laboratory Standards Institute broth microdilution method. FINDINGS The proposed ECV, in µg/mL, for AMB, ITR, KET, POS, and TRB were 4.0, 2.0, 1.0, 2.0, and 0.25, respectively. Percentages of wild-type strains in our population for the above antifungal drugs were 98.48, 95.22, 95.33, 100, and 97.67%, respectively. MAIN CONCLUSIONS These ECVs will be useful to detect strains with resistance, to define CBPs, and to elaborate specific therapeutic guidelines for S. brasiliensis. Rational use of antifungals is strongly recommended to avoid the emergence of resistant strains and ensure the therapeutic effectiveness of sporotrichosis. PMID:28443986

  8. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Cerataphis brasiliensis

    USDA-ARS?s Scientific Manuscript database

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the palm aphid, Cerataphis brasiliensis, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures...

  9. L-Canavanine, a Dietary Nitrogen Source for the Seed Predator Caryedes brasiliensis (Bruchidae).

    PubMed

    Rosenthal, G A; Hughes, C G; Janzen, D H

    1982-07-23

    Larvae of the bruchid beetle Caryedes brasiliensis (Bruchidae) develop entirely within the seed of the neotropical legume Dioclea megacarpa. The seed contains an appreciable concentration of L-canavanine, a potent antimetabolite and structural analog of L-arginine. This bruchid beetle uses the nitrogen stored in this toxic allelochemical as an effective dietary nitrogen source for amino acid biosynthesis.

  10. Avoidance of nonprotein amino acid incorporation into protein by the seed predator,Caryedes brasiliensis (Bruchidae).

    PubMed

    Rosenthal, G A; Janzen, D H

    1983-09-01

    Larvae of the bruchid beetle,Caryedes brasiliensis (Bruchidae) have the ability to avoid significant incorporation ofL-canavanine, the guanidinooxy structural analog ofL-arginine, into de novo synthesized proteins. This ability is related to a highly discriminatory protein-synthesizing system which exhibits marked ability to avoid processing an array of nonprotein amino acids structurally related to arginine.

  11. Sporothrix schenckii sensu stricto and Sporothrix brasiliensis Are Differentially Recognized by Human Peripheral Blood Mononuclear Cells.

    PubMed

    Martínez-Álvarez, José A; Pérez-García, Luis A; Mellado-Mojica, Erika; López, Mercedes G; Martínez-Duncker, Iván; Lópes-Bezerra, Leila M; Mora-Montes, Héctor M

    2017-01-01

    Sporothrix schenckii sensu stricto and S. brasiliensis are usually associated to sporotrichosis, a subcutaneous mycosis worldwide distributed. Comparative analyses between these two species indicate they contain genetic and physiological differences that are likely to impact the interaction with host cells. Here, we study the composition of the cell wall from conidia, yeast-like cells and germlings of both species and found they contained the same sugar composition. The carbohydrate proportion in the S. schenckii sensu stricto wall was similar across the three cell morphologies, with exception in the chitin content, which was significantly different in the three morphologies. The cell wall from germlings showed lower rhamnose content and higher glucose levels than other cell morphologies. In S. brasiliensis, the wall sugars were constant in the three morphologies, but glucose was lower in yeast-like cells. In S. schenckii sensu stricto cells most of chitin and β1,3-glucan were underneath wall components, but in S. brasiliensis germlings, chitin was exposed at the cell surface, and β1,3-glucan was found in the outer part of the conidia wall. We also compared the ability of these cells to stimulate cytokine production by human peripheral blood mononuclear cells. The three S. schenckii sensu stricto morphologies stimulated increased levels of pro-inflammatory cytokines, when compared to S. brasiliensis cells; while the latter, with exception of conidia, stimulated higher IL-10 levels. Dectin-1 was a key receptor for cytokine production during stimulation with the three morphologies of S. schenckii sensu stricto, but dispensable for cytokine production stimulated by S. brasiliensis germlings. TLR2 and TLR4 were also involved in the sensing of Sporothrix cells, with a major role for the former during cytokine stimulation. Mannose receptor had a minor contribution during cytokine stimulation by S. schenckii sensu stricto yeast-like cells and germlings, but S. schenckii

  12. Sporothrix schenckii sensu stricto and Sporothrix brasiliensis Are Differentially Recognized by Human Peripheral Blood Mononuclear Cells

    PubMed Central

    Martínez-Álvarez, José A.; Pérez-García, Luis A.; Mellado-Mojica, Erika; López, Mercedes G.; Martínez-Duncker, Iván; Lópes-Bezerra, Leila M.; Mora-Montes, Héctor M.

    2017-01-01

    Sporothrix schenckii sensu stricto and S. brasiliensis are usually associated to sporotrichosis, a subcutaneous mycosis worldwide distributed. Comparative analyses between these two species indicate they contain genetic and physiological differences that are likely to impact the interaction with host cells. Here, we study the composition of the cell wall from conidia, yeast-like cells and germlings of both species and found they contained the same sugar composition. The carbohydrate proportion in the S. schenckii sensu stricto wall was similar across the three cell morphologies, with exception in the chitin content, which was significantly different in the three morphologies. The cell wall from germlings showed lower rhamnose content and higher glucose levels than other cell morphologies. In S. brasiliensis, the wall sugars were constant in the three morphologies, but glucose was lower in yeast-like cells. In S. schenckii sensu stricto cells most of chitin and β1,3-glucan were underneath wall components, but in S. brasiliensis germlings, chitin was exposed at the cell surface, and β1,3-glucan was found in the outer part of the conidia wall. We also compared the ability of these cells to stimulate cytokine production by human peripheral blood mononuclear cells. The three S. schenckii sensu stricto morphologies stimulated increased levels of pro-inflammatory cytokines, when compared to S. brasiliensis cells; while the latter, with exception of conidia, stimulated higher IL-10 levels. Dectin-1 was a key receptor for cytokine production during stimulation with the three morphologies of S. schenckii sensu stricto, but dispensable for cytokine production stimulated by S. brasiliensis germlings. TLR2 and TLR4 were also involved in the sensing of Sporothrix cells, with a major role for the former during cytokine stimulation. Mannose receptor had a minor contribution during cytokine stimulation by S. schenckii sensu stricto yeast-like cells and germlings, but S. schenckii

  13. Cloning, killing, and identity.

    PubMed Central

    McMahan, J

    1999-01-01

    One potentially valuable use of cloning is to provide a source of tissues or organs for transplantation. The most important objection to this use of cloning is that a human clone would be the sort of entity that it would be seriously wrong to kill. I argue that entities of the sort that you and I essentially are do not begin to exist until around the seventh month of fetal gestation. Therefore to kill a clone prior to that would not be to kill someone like you or me but would be only to prevent one of us from existing. And even after one of us begins to exist, the objections to killing it remain comparatively weak until its psychological capacities reach a certain level of maturation. These claims support the permissibility of killing a clone during the early stages of its development in order to use its organs for transplantation. PMID:10226909

  14. Characterization of Paracoccidioides brasiliensis by FT-IR spectroscopy and nanotechnology

    NASA Astrophysics Data System (ADS)

    Ferreira, Isabelle; Ferreira-Strixino, Juliana; Castilho, Maiara L.; Campos, Claudia B. L.; Tellez, Claudio; Raniero, Leandro

    2016-01-01

    Paracoccidioides brasiliensis, the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25 °C in vitro) and as yeast cells in the human host (or at 37 °C in vitro). Because mycological examination of lesions in patients frequently is unable to show the presence of the fungus and serological tests can misdiagnose the disease with other mycosis, the development of new approach's for molecular identification of P. brasiliensis spurges is needed. This study describes the use of a gold nanoprobe of a known gene sequence of P. brasiliensis as a molecular tool to identify P. brasiliensis by regular polymerase chain reaction (PCR) associated with a colorimetric methods. This approach is suitable for testing in remote areas because it does not require any further step than gene amplification, being safer and cheaper than electrophoresis methods. The proposed test showed a color change of the PCR reaction mixture from red to blue in negative samples, whereas the solution remains red in positive samples. We also performed a Fourier Transform Infrared (FT-IR) Spectroscopy analysis to characterize and compare the chemical composition between yeast and mycelia forms, which revealed biochemical differences between these two forms. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates. The most prominent difference between both forms was vibration modes related to 1,3-β-glucan usually found in mycelia and 1,3-α-glucan found in yeasts and also chitin forms. In this work, we introduce FT-IR as a new method suitable to reveal overall differences that biochemically distinguish each form of P. brasiliensis that could be additionally used to discriminate biochemical differences among a single form under distinct environmental conditions.

  15. Characterization of Paracoccidioides brasiliensis by FT-IR spectroscopy and nanotechnology.

    PubMed

    Ferreira, Isabelle; Ferreira-Strixino, Juliana; Castilho, Maiara L; Campos, Claudia B L; Tellez, Claudio; Raniero, Leandro

    2016-01-05

    Paracoccidioides brasiliensis, the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25°C in vitro) and as yeast cells in the human host (or at 37°C in vitro). Because mycological examination of lesions in patients frequently is unable to show the presence of the fungus and serological tests can misdiagnose the disease with other mycosis, the development of new approach's for molecular identification of P. brasiliensis spurges is needed. This study describes the use of a gold nanoprobe of a known gene sequence of P. brasiliensis as a molecular tool to identify P. brasiliensis by regular polymerase chain reaction (PCR) associated with a colorimetric methods. This approach is suitable for testing in remote areas because it does not require any further step than gene amplification, being safer and cheaper than electrophoresis methods. The proposed test showed a color change of the PCR reaction mixture from red to blue in negative samples, whereas the solution remains red in positive samples. We also performed a Fourier Transform Infrared (FT-IR) Spectroscopy analysis to characterize and compare the chemical composition between yeast and mycelia forms, which revealed biochemical differences between these two forms. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates. The most prominent difference between both forms was vibration modes related to 1,3-β-glucan usually found in mycelia and 1,3-α-glucan found in yeasts and also chitin forms. In this work, we introduce FT-IR as a new method suitable to reveal overall differences that biochemically distinguish each form of P. brasiliensis that could be additionally used to discriminate biochemical differences among a single form under distinct environmental conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Humoral Immunity through Immunoglobulin M Protects Mice from an Experimental Actinomycetoma Infection by Nocardia brasiliensis

    PubMed Central

    Salinas-Carmona, Mario C.; Pérez-Rivera, Isabel

    2004-01-01

    An experimental model of infection with Nocardia brasiliensis, used as an example of a facultative intracellular pathogen, was tested. N. brasiliensis was injected into the rear foot pads of BALB/c mice to establish an infection. Within 30 days, infected animals developed a chronic actinomycetoma infection. Batch cultures of N. brasiliensis were used to purify P61, P38, and P24 antigens; P61 is a catalase, and P38 is a protease with strong caseinolytic activity. Active and passive immunizations of BALB/c mice with these three purified soluble antigens were studied. Protection was demonstrated for actively immunized mice. However, immunity lasted only 30 days. Other groups of immunized mice were bled at different times, and their sera were passively transferred to naive recipients that were then infected with N. brasiliensis. Sera collected 5, 6, and 7 days after donor immunization conferred complete, long-lasting protection. The protective effect of passive immunity decreased when sera were collected 2 weeks after donor immunization. However, neither the early sera (1-, 2-, and 3-day sera) nor the later sera (30- or 45-day sera) prevented the infection. Hyperimmune sera with the highest levels of immunoglobulin G (IgG) to N. brasiliensis antigens did not protect at all. The antigens tested induced two IgM peaks. The first peak was present 3 days after immunization but was not antigen specific and did not transfer protection. The second peak was evident 7 days after immunization, was an IgM response, was antigen specific, and conferred protection. This results clearly demonstrate that IgM antibodies protect the host against a facultative intracellular bacterium. PMID:15385456

  17. Ethrel-stimulated prolongation of latex flow in the rubber tree (Hevea brasiliensis Muell. Arg.): an Hev b 7-like protein acts as a universal antagonist of rubber particle aggregating factors from lutoids and C-serum.

    PubMed

    Shi, Min-Jing; Cai, Fu-Ge; Tian, Wei-Min

    2016-02-01

    Ethrel is the most effective stimuli in prolonging the latex flow that consequently increases yield per tapping. This effect is largely ascribed to the enhanced lutoid stability, which is associated with the decreased release of initiators of rubber particle (RP) aggregation from lutoid bursting. However, the increase in both the bursting index of lutoids and the duration of latex flow after applying ethrel or ethylene gas in high concentrations suggests that a new mechanism needs to be introduced. In this study, a latex allergen Hev b 7-like protein in C-serum was identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI TOF MS). In vitro analysis showed that the protein acted as a universal antagonist of RP aggregating factors from lutoids and C-serum. Ethrel treatment obviously weakened the effect of C-serum on RP aggregation, which was closely associated with the increase in the level of the Hev b 7-like protein and the decrease in the level of the 37 kDa protein, as revealed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), western blotting analysis and antibody neutralization. Thus, the increase of the Hev b 7-like protein level or the ratio of the Hev b 7-like protein to the 37 kDa protein in C-serum should be primarily ascribed to the ethrel-stimulated prolongation of latex flow duration.

  18. Morphometric and high resolution scanning electron microscopy analysis of low-level laser therapy and latex protein (Hevea brasiliensis) administration following a crush injury of the sciatic nerve in rats.

    PubMed

    Dias, Fernando J; Issa, João Paulo M; Coutinho-Netto, Joaquim; Fazan, Valéria P S; Sousa, Luiz Gustavo; Iyomasa, Mamie M; Papa, Paula C; Watanabe, Ii-Sei

    2015-02-15

    This study evaluated the effect of low-level laser therapy (LLLT; 15 J/cm(2)) and a latex protein (F1) on a crush injury of the sciatic (ischiadicus) nerve. Seventy-two rats (male, 250 g) were divided into 6 groups: CG, control; EG, exposed nerve; IG, injured nerve without treatment; LG, injured nerve with LLLT; HG, injured nerve with F1; and LHG, injured nerve with LLLT and F1. After 4 or 8 weeks, the animals were euthanized and samples of the sciatic nerve were collected for morphometric and high-resolution scanning electron microscopy (HRSEM) analysis. After 4 weeks, the morphometry revealed improvements in the treated animals, and the HG appeared to be the most similar to the CG; after 8 weeks, the injured groups showed improvements compared to the previous period, and the results of the treatment groups were more similar to one another. At HRSEM after 4 weeks, the treated groups were similar and showed improvement compared to the IG; after 8 weeks, the LHG and HG had the best results. In conclusion, the treatments resulted in improvement after the nerve injury, and this recovery was time-dependent. In addition, the use of the F1 resulted in the best morphometric and ultrastructural findings.

  19. Application of a low-level laser therapy and the purified protein from natural latex (Hevea brasiliensis) in the controlled crush injury of the sciatic nerve of rats: a morphological, quantitative, and ultrastructural study.

    PubMed

    Dias, Fernando José; Issa, João Paulo Mardegan; Iyomasa, Mamie Mizusaki; Coutinho-Netto, Joaquim; Calzzani, Ricardo Alexandre Junqueria; Iyomasa, Daniela Mizusaki; Sousa, Luiz Gustavo; de Almeida, Sonia Regina Yokomizo; Cury, Diego Pulzatto; Watanabe, Ii-sei

    2013-01-01

    This study analyzed the effects of a low-level laser therapy (LLLT, 15 J/cm(2), 780 nm wavelength) and the natural latex protein (P1, 0.1%) in sciatic nerve after crush injury (15 Kgf, axonotmesis) in rats. Sixty rats (male, 250 g) were allocated into the 6 groups (n = 10): CG-control group; EG-nerve exposed; IG-injured nerve without treatment; LG-crushed nerve treated with LLLT; PG-injured nerve treated with P1; and LPG-injured nerve treated with LLLT and P1. After 4 or 8 weeks, the nerve samples were processed for morphological, histological quantification and ultrastructural analysis. After 4 weeks, the myelin density and morphological characteristics improved in groups LG, PG, and LPG compared to IG. After 8 weeks, PG, and LPG were similar to CG and the capillary density was higher in the LG, PG, and LPG. In the ultrastructural analysis the PG and LPG had characteristics that were similar to the CG. The application of LLLT and/or P1 improved the recovery from the nerve crush injury, and in the long term, the P1 protein was the better treatment used, since only the application of LLLT has not reached the same results, and these treatments applied together did not potentiate the recovery.

  20. Ethrel-stimulated prolongation of latex flow in the rubber tree (Hevea brasiliensis Muell. Arg.): an Hev b 7-like protein acts as a universal antagonist of rubber particle aggregating factors from lutoids and C-serum

    PubMed Central

    Shi, Min-Jing; Cai, Fu-Ge; Tian, Wei-Min

    2016-01-01

    Ethrel is the most effective stimuli in prolonging the latex flow that consequently increases yield per tapping. This effect is largely ascribed to the enhanced lutoid stability, which is associated with the decreased release of initiators of rubber particle (RP) aggregation from lutoid bursting. However, the increase in both the bursting index of lutoids and the duration of latex flow after applying ethrel or ethylene gas in high concentrations suggests that a new mechanism needs to be introduced. In this study, a latex allergen Hev b 7-like protein in C-serum was identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI TOF MS). In vitro analysis showed that the protein acted as a universal antagonist of RP aggregating factors from lutoids and C-serum. Ethrel treatment obviously weakened the effect of C-serum on RP aggregation, which was closely associated with the increase in the level of the Hev b 7-like protein and the decrease in the level of the 37 kDa protein, as revealed by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE), western blotting analysis and antibody neutralization. Thus, the increase of the Hev b 7-like protein level or the ratio of the Hev b 7-like protein to the 37 kDa protein in C-serum should be primarily ascribed to the ethrel-stimulated prolongation of latex flow duration. PMID:26381537

  1. On cloning human beings.

    PubMed

    de Melo-Martin, Inmaculada

    2002-06-01

    The purpose of this paper is to show that arguments for and against cloning fail to make their case because of one or both of the following reasons: 1) they take for granted customary beliefs and assumptions that are far from being unquestionable; 2) they tend to ignore the context in which human cloning is developed. I will analyze some of the assumptions underlying the main arguments that have been offered for and against cloning. Once these assumptions are critically analyzed, arguments both rejecting and supporting human cloning seem to lose weight. I will first briefly present the main arguments that have been proposed against cloning and I will argue that they fail to establish their case. In the next section I will evaluate some of the positive arguments that have been offered supporting such technology. This analysis will show that the case for cloning also fails. Finally, I will maintain that because critics and especially supporters of this technology neglect the context in which human cloning is developed and might be implemented, their arguments are far from compelling.

  2. [Human cloning or cannibalism].

    PubMed

    Sokolowski, L M

    2001-01-01

    In this article I develop the idea presented in my previous work that human cloning would be of little practical use since almost any aim that one would like to attain by multiple cloning of a concrete man or a group of people, are unattainable or it might be achieved by easier, cheaper and more efficient traditional methods. For this reason cloning of a man is unlikely to occur on a larger scale and only few people will decide to clone themselves. In this sense no social effects of human cloning will be disastrous for the human population. Yet investigations in human genetics are very important since they may provide medical applications far more important than human cloning. It is argued that the main trend of modern medicine: organ transplantation from an alien donor, will become socially dangerous in near future since the number of donors will be drastically smaller than the number of potential patients waiting for transplantations. This in turn may cause social conflicts and a form of medical cannibalism may arise. These problems and conflicts will be avoided if organ transplantation from an alien donor is replaced by organ cloning, i.e. by transplanting an organ developed from the patient.

  3. Functional and structural optimization of the respiratory system of the bat Tadarida brasiliensis (Chiroptera, Molossidae): does airway geometry matter?

    PubMed

    Canals, Mauricio; Atala, Cristian; Olivares, Ricardo; Guajardo, Francisco; Figueroa, Daniela P; Sabat, Pablo; Rosenmann, Mario

    2005-10-01

    We studied structure and function of the respiratory system in the bat Tadarida brasiliensis and compared it with those of two species of rodents, Abrothrix andinus and A. olivaceus. Tadarida brasiliensis had lower resting oxygen consumption, but higher maximum oxygen consumption and aerobic scope, than the rodents. The blood-gas barrier of the bat was thinner and its relative lung size was larger; however, alveolar surface density was similar among the three species. In consequence, T. brasiliensis has an oxygen diffusion capacity two or three times higher than that of the rodents. In Tadarida brasiliensis the characteristics of the lung were accompanied by geometrical changes in the proximal airway, such as high physical optimization as a consequence of small variations in the symmetry and the scaling ratio of the bronchial diameters. These may constitute an efficient way to save energy in respiratory mechanics and are the first report of airway adjustments to decrease entropy generation in bats.

  4. Role of protein kinase C in cytokine secretion by lung epithelial cells during infection with Paracoccidioides brasiliensis

    PubMed Central

    Alcantara, Cristiane; Maza, Paloma Korehisa; Barros, Bianca Carla Silva Campitelli; Suzuki, Erika

    2015-01-01

    In this study, we investigated the role of protein kinases C (PKCs) in interleukin (IL)-6 and IL-8 secretion by human lung epithelial A549 cells during infection with the fungal pathogen Paracoccidioides brasiliensis. Rottlerin and the broad spectrum PKC inhibitor Go 6983 reduced cytokine levels in A549 cell–P. brasiliensis cultures. Next, by western blot, we verified that infection with this fungus led to phosphorylation of PKC δ (Thr505). By using a peptide inhibitor for PKC δ or PKC δ short interfering RNA technique, IL-6 and IL-8 levels in A549–P. brasiliensis cultures were also reduced. Together, these results indicate that P. brasiliensis promotes IL-6 and IL-8 secretion by A549 cells in a PKC δ-dependent manner. PMID:26152710

  5. Changes in kinematics and aerodynamics over a range of speeds in Tadarida brasiliensis, the Brazilian free-tailed bat.

    PubMed

    Hubel, Tatjana Y; Hristov, Nickolay I; Swartz, Sharon M; Breuer, Kenneth S

    2012-06-07

    To date, wake measurements using particle image velocimetry (PIV) of bats in flight have studied only three bat species, all fruit and nectar feeders. In this study, we present the first wake structure analysis for an insectivorous bat. Tadarida brasiliensis, the Brazilian free-tailed bat, is an aerial hunter that annually migrates long distances and also differs strikingly from the previously investigated species morphologically. We compare the aerodynamics of T. brasiliensis with those of other, frugivorous bats and with common swifts, Apus apus, a bird with wing morphology, kinematics and flight ecology similar to that of these bats. The comparison reveals that, for the range of speeds evaluated, the cyclical pattern of aerodynamic forces associated with a wingbeat shows more similarities between T. brasiliensis and A. apus than between T. brasiliensis and other frugivorous bats.

  6. Redescription of Urophycis brasiliensis (Kaup 1858), a senior synonym of Urophycis latus Miranda Ribeiro 1903 (Gadiformes: Phycidae).

    PubMed

    Lemes, Paola C R; Loeb, Marina V; Santificetur, César; Melo, Marcelo R S

    2016-02-29

    Urophycis Gill 1864 is a genus of demersal fish composed by eight valid species with anti-tropical distributions in the western Atlantic. Only two species occur in the South Atlantic: U. brasiliensis (Kaup 1858) and U. mystacea Miranda Ribeiro 1903. These species have similar ranges from southeastern Brazil to northern Argentina, but U. brasiliensis occurs in more shallow waters than U. mystacea. Both species are important fishery resources in southern Brazil and Uruguay. Herein, we redescribe U. brasiliensis based on comparison of types and additional specimens, including the description of the Sagitta otolith, formerly place U. latus Miranda Ribeiro 1903 as a junior synonym of U. brasiliensis, and provide an updated map of distribution.

  7. Immunity-dependent reduction of segmented filamentous bacteria in mice infected with the helminthic parasite Nippostrongylus brasiliensis

    USDA-ARS?s Scientific Manuscript database

    Immune modulation by helminth (worm) parasites could protect the host against autoimmune diseases. We report that the parasitic nematode Nippostrongylus brasiliensis induces changes in the expression of antimicrobial peptides that are associated with marked microbial composition shifts, including re...

  8. Changes in kinematics and aerodynamics over a range of speeds in Tadarida brasiliensis, the Brazilian free-tailed bat

    PubMed Central

    Hubel, Tatjana Y.; Hristov, Nickolay I.; Swartz, Sharon M.; Breuer, Kenneth S.

    2012-01-01

    To date, wake measurements using particle image velocimetry (PIV) of bats in flight have studied only three bat species, all fruit and nectar feeders. In this study, we present the first wake structure analysis for an insectivorous bat. Tadarida brasiliensis, the Brazilian free-tailed bat, is an aerial hunter that annually migrates long distances and also differs strikingly from the previously investigated species morphologically. We compare the aerodynamics of T. brasiliensis with those of other, frugivorous bats and with common swifts, Apus apus, a bird with wing morphology, kinematics and flight ecology similar to that of these bats. The comparison reveals that, for the range of speeds evaluated, the cyclical pattern of aerodynamic forces associated with a wingbeat shows more similarities between T. brasiliensis and A. apus than between T. brasiliensis and other frugivorous bats. PMID:22258554

  9. Development and characterization of microsatellite markers for the medicinal plant Smilax brasiliensis (Smilacaceae) and related species1

    PubMed Central

    Martins, Aline R.; Abreu, Aluana G.; Bajay, Miklos M.; Villela, Priscilla M. S.; Batista, Carlos E. A.; Monteiro, Mariza; Alves-Pereira, Alessandro; Figueira, Glyn M.; Pinheiro, José B.; Appezzato-da-Glória, Beatriz; Zucchi, Maria I.

    2013-01-01

    • Premise of the study: A new set of microsatellite or simple sequence repeat (SSR) markers were developed for Smilax brasiliensis, which is popularly known as sarsaparilla and used in folk medicine as a tonic, antirheumatic, and antisyphilitic. Smilax brasiliensis is sold in Brazilian pharmacies, and its origin and effectiveness are not subject to quality control. • Methods and Results: Using a protocol for genomic library enrichment, primer pairs were developed for 26 microsatellite loci and validated in 17 accessions of S. brasiliensis. Thirteen loci were polymorphic and four were monomorphic. The primers successfully amplified alleles in the congeners S. campestris, S. cissoides, S. fluminensis, S. goyazana, S. polyantha, S. quinquenervia, S. rufescens, S. subsessiliflora, and S. syphilitica. • Conclusions: The new SSR markers described herein are informative tools for genetic diversity and gene flow studies in S. brasiliensis and several congeners. PMID:25202555

  10. Differences in cell morphometry, cell wall topography and gp70 expression correlate with the virulence of Sporothrix brasiliensis clinical isolates.

    PubMed

    Castro, Rafaela A; Kubitschek-Barreira, Paula H; Teixeira, Pedro A C; Sanches, Glenda F; Teixeira, Marcus M; Quintella, Leonardo P; Almeida, Sandro R; Costa, Rosane O; Camargo, Zoilo P; Felipe, Maria S S; de Souza, Wanderley; Lopes-Bezerra, Leila M

    2013-01-01

    Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes.

  11. Macrophage Interaction with Paracoccidioides brasiliensis Yeast Cells Modulates Fungal Metabolism and Generates a Response to Oxidative Stress

    PubMed Central

    Parente-Rocha, Juliana Alves; Parente, Ana Flávia Alves; Baeza, Lilian Cristiane; Bonfim, Sheyla Maria Rondon Caixeta; Hernandez, Orville; McEwen, Juan G.; Bailão, Alexandre Melo; Taborda, Carlos Pelleschi; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

    2015-01-01

    Macrophages are key players during Paracoccidioides brasiliensis infection. However, the relative contribution of the fungal response to counteracting macrophage activity remains poorly understood. In this work, we evaluated the P. brasiliensis proteomic response to macrophage internalization. A total of 308 differentially expressed proteins were detected in P. brasiliensis during infection. The positively regulated proteins included those involved in alternative carbon metabolism, such as enzymes involved in gluconeogenesis, beta-oxidation of fatty acids and amino acids catabolism. The down-regulated proteins during P. brasiliensis internalization in macrophages included those related to glycolysis and protein synthesis. Proteins involved in the oxidative stress response in P. brasiliensis yeast cells were also up-regulated during macrophage infection, including superoxide dismutases (SOD), thioredoxins (THX) and cytochrome c peroxidase (CCP). Antisense knockdown mutants evaluated the importance of CCP during macrophage infection. The results suggested that CCP is involved in a complex system of protection against oxidative stress and that gene silencing of this component of the antioxidant system diminished the survival of P. brasiliensis in macrophages and in a murine model of infection. PMID:26360774

  12. Isolation of Paracoccidioides brasiliensis from armadillos (Dasypus novemcinctus) in an area where the fungus was recently isolated from soil.

    PubMed

    Silva-Vergara, M L; Martinez, R; Camargo, Z P; Malta, M H; Maffei, C M; Chadu, J B

    2000-06-01

    Natural infection of armadillos (Dasypus novemcinctus) with Paracoccidioides brasiliensis in Northern Brazil was reported in 1986, raising great interest in the understanding of the role of this mammal in the epidemiological cycle of the fungus. Recently, P. brasiliensis was isolated from the soil of Ibiá, State of Minas Gerais, southeastern Brazil. Armadillos captured in this area were evaluated for the presence of P. brasiliensis in the viscera and infection was detected in 4/16 animals (25%). Fungal yeast phase cells were observed in three of the four infected armadillos by direct microscopic examination and by the indirect immunofluorescence test carried out on homogenized tissues. P. brasiliensis was isolated from three armadillos whose homogenized viscera had been injected into Swiss mice. The new strains (Ibiá-T1, Ibiá-T2 and Ibiá-T3) were identified as P. brasiliensis on the basis of macro- and micromorphology, thermodimorphism, production and serologic activity of exoantigens, and by polymerase chain reaction (PCR)-detection of the gp43 gene. The lethality and lesions caused to the mice from which the strains were recovered confirmed the virulence of the isolates. We conclude that P. brasiliensis infects armadillos in locations with different geoclimatic characteristics and vegetation cover. The direct observation of yeast cells in tissues and the multiple visceral involvement, including the lungs, suggests the occurrence of paracoccidioidomycosis disease in these mammals and supports their role as wild hosts in the epidemiological cycle of the fungus.

  13. Human cord blood T-cell receptor alpha beta cell responses to protein antigens of Paracoccidioides brasiliensis yeast forms.

    PubMed Central

    Munk, M E; Kaufmann, S H

    1995-01-01

    Paracoccidioides brasiliensis causes a chronic granulomatous mycosis, prevalent in South America, and cell-mediated immunity represents the principal mode of protection against this fungal infection. We investigated the response of naive cord blood T cells to P. brasiliensis lysates. Our results show: (1) P. brasiliensis stimulates T-cell expansion, interleukin-2 (IL-2) production and differentiation into cytotoxic T cells; (2) T-cell stimulation depends on P. brasiliensis processing and major histocompatibility complex (MHC) class II expression; (3) the responsive T-cell population expresses alpha beta T-cell receptors (TCR) with different V beta gene products, CD4 and CD45RO; (4) the P. brasiliensis components involved in T-cell expansion primarily reside in a high molecular weight (100,000 MW) and a low molecular weight (< 1000 MW) protein fraction. These results indicate that protein antigens of P. brasiliensis stimulate cord blood CD4 alpha beta T cells, independent from in vivo presensitization, and thus question direct correlation of positive in vitro responses with protective immunity in vivo. PMID:7890308

  14. Interspecific interactions involving Neoseiulus californicus (Acari: Phytoseiidae) and Agistemus brasiliensis (Acari: Stigmaeidae) as predators of Brevipalpus phoenicis (Acari: Tenuipalpidae).

    PubMed

    da Silva, Marcos Zatti; Sato, Mário Eidi; de Oliveira, Carlos Amadeu Leite; Nicastro, Roberto Lomba

    2015-03-01

    Brevipalpus phoenicis (Geijskes) is associated with the transmission of Citrus leprosis which is considered the main viral disease for the Brazilian citrus production. Mites of the families Stigmaeidae and Phytoseiidae coexist in various agricultural crops, often promoting the biological control of pest mites. The aim of this work was to study the interactions of Neoseiulus californicus (McGregor) (Phytoseiidae) and Agistemus brasiliensis Matioli, Ueckermann & Oliveira (Stigmaeidae), in the presence or absence of B. phoenicis. Two experiments were carried out. In the first, a N. californicus female was placed in each leaf disc arena, with eggs of B. phoenicis and A. brasiliensis as food sources. In the second, an A. brasiliensis female was placed in each arena, with eggs of B. phoenicis and N. californicus as food sources. Adults of both predators were able to consume both types of eggs available as food sources, but they fed on considerably higher proportions of B. phoenicis than on eggs of the predator. Eggs of A. brasiliensis were not a suitable food source for N. californicus, which produced only 0.1 egg per female per day when only eggs of that species were present in the experimental unit. The results suggest that eggs of N. californicus were a suitable food source for A. brasiliensis, which oviposited 1.12 eggs per day, when only eggs of N. californicus were provided to the stigmaeid mite. The possible interactions among N. californicus, A. brasiliensis and B. phoenicis in citrus orchards are discussed.

  15. Macrophage Interaction with Paracoccidioides brasiliensis Yeast Cells Modulates Fungal Metabolism and Generates a Response to Oxidative Stress.

    PubMed

    Parente-Rocha, Juliana Alves; Parente, Ana Flávia Alves; Baeza, Lilian Cristiane; Bonfim, Sheyla Maria Rondon Caixeta; Hernandez, Orville; McEwen, Juan G; Bailão, Alexandre Melo; Taborda, Carlos Pelleschi; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

    2015-01-01

    Macrophages are key players during Paracoccidioides brasiliensis infection. However, the relative contribution of the fungal response to counteracting macrophage activity remains poorly understood. In this work, we evaluated the P. brasiliensis proteomic response to macrophage internalization. A total of 308 differentially expressed proteins were detected in P. brasiliensis during infection. The positively regulated proteins included those involved in alternative carbon metabolism, such as enzymes involved in gluconeogenesis, beta-oxidation of fatty acids and amino acids catabolism. The down-regulated proteins during P. brasiliensis internalization in macrophages included those related to glycolysis and protein synthesis. Proteins involved in the oxidative stress response in P. brasiliensis yeast cells were also up-regulated during macrophage infection, including superoxide dismutases (SOD), thioredoxins (THX) and cytochrome c peroxidase (CCP). Antisense knockdown mutants evaluated the importance of CCP during macrophage infection. The results suggested that CCP is involved in a complex system of protection against oxidative stress and that gene silencing of this component of the antioxidant system diminished the survival of P. brasiliensis in macrophages and in a murine model of infection.

  16. Do Managers Clone Themselves?

    ERIC Educational Resources Information Center

    Baron, Alma S.

    1981-01-01

    A recent questionnaire survey provides statistics on male managers' views of female managers. The author recommends that male managers break out of their cloning behavior and that the goal ought to be a plurality in management. (Author/WD)

  17. Clone clustering by hybridization

    SciTech Connect

    Milosavijevic, A.; Zeremski, M.; Paunesku, T.

    1995-05-01

    DNA sequencing by hybridization (SBH) Format 1 technique is based on experiments in which thousands of short oligomers are consecutively hybridized with dense arrays of clones. In this paper the authors present the description of a method for obtaining hybridization signatures for individual clones that guarantees reproducibility despite a wide range of variations in experimental circumstances, a sensitive method for signature comparison at prespecified significance levels, and a clustering algorithm that correctly identifies clusters of significantly similar signatures. The methods and the algorithm have been verified experimentally on a control set of 422 signatures that originate from 9 distinct clones of known sequence. Experiments indicate that only 30 to 50 oligomer probes suffice for correct clustering. This information about the identity of clones can be used to guide both genomic and cDNA sequencing by SBH or by standard gel-based methods. 12 refs., 5 figs., 2 tabs.

  18. Do Managers Clone Themselves?

    ERIC Educational Resources Information Center

    Baron, Alma S.

    1981-01-01

    A recent questionnaire survey provides statistics on male managers' views of female managers. The author recommends that male managers break out of their cloning behavior and that the goal ought to be a plurality in management. (Author/WD)

  19. Statement on Human Cloning

    MedlinePlus

    ... form Search American Association for the Advancement of Science Statement on Human Cloning Tweet The American Association for the Advancement of Science (AAAS) recognizes the intense debates within our society ...

  20. Statement on Human Cloning

    MedlinePlus

    ... form Search American Association for the Advancement of Science Statement on Human Cloning Tweet The American Association for the Advancement of Science (AAAS) recognizes the intense debates within our society ...

  1. Twins: A cloning experience.

    PubMed

    Prainsack, Barbara; Spector, Tim D

    2006-11-01

    Drawing upon qualitative interviews with monozygotic (identical) twins sharing 100% of their genes, and with dizygotic (fraternal) twins and singletons as control groups, this paper explores what it means to be genetically identical. (The twins interviewed were from the TwinsUK register in London.) In the context of the ongoing debate on human reproductive cloning, it examines questions such as: To what extent do identical twins perceive their emotional and physical bond to be a result of their genetic makeup? What would they think if they had been deliberately created genetically identical? How would they feel about being genetically identical to a person who was born a few years earlier or later? First, our respondents ascribed no great significance to the role of genes in their understanding of what it means to be identical twins. Second, the opinion that human reproductive cloning would "interfere with nature", or "contradict God's will", was expressed by our respondents exclusively on the abstract level. The more our respondents were able to relate a particular invented cloning scenario to their own life-worlds, the lower the prevalence of the argument. Third, for all three groups of respondents, the scenario of having been born in one of the other groups was perceived as strange. Fourth, the aspect that our respondents disliked about cloning scenarios was the potential motives of the cloners. Without equating monozygotic twins directly with "clones", these results from "naturally" genetically identical individuals add a new dimension to what a future cloning situation could entail: The cloned person might possibly (a) perceive a close physical and emotional connection to the progenitor as a blessing; (b) suffer from preconceptions of people who regard physical likeness as a sign of incomplete individuality; and (c) perceive the idea of not having been born a clone of a particular person as unpleasant.

  2. A Common Caatinga Cactus, Pilosocereus gounellei, is an Important Ecotope of Wild Triatoma brasiliensis Populations in the Jaguaribe Valley of Northeastern Brazil

    PubMed Central

    Valença-Barbosa, Carolina; Lima, Marli M.; Sarquis, Otília; Bezerra, Claudia M.; Abad-Franch, Fernando

    2014-01-01

    Triatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops. However, this species frequently infests/re-infests houses in rock-free sedimentary lowlands. We therefore hypothesized that it should also occupy other natural ecotopes. We show that a common Caatinga cactus, Pilosocereus gounellei, locally known as xiquexique, often harbors T. brasiliensis breeding colonies apparently associated with rodents (n = 44 cacti, infestation rate = 47.7%, 157 bugs captured). Our findings suggest that infested cacti might be involved in house re-infestation by T. brasiliensis in the Caatinga region. PMID:24710611

  3. Alloreactive T cell clones.

    PubMed

    Fitch, F W

    1984-01-01

    T cell clones are useful models for studying lymphocyte function both at the level of the individual cell and in interacting systems. Murine cytolytic and non- cytolyic T cell clones have been obtained with relative ease, and the particular procedure used to derive and maintain T cell clones may influence profoundly the characteristics of the resulting cells. The method of choice depends on the specific question to be asked. Although some clones have characteristics that would have been expected on the basis of results observed with bulk cell populations, other clones have rather unexpected properties. Although most T cell clones appear to be either cytolytic or non-cytolytic, this distinction is not always absolute. A high proportion of both cytolytic and non-cytolytic T cell clones have dual reactivity. This is true for cells which by other criteria appear to be true clones. The frequency of such cells is high enough to suggest that most if not all T cells may have reactivity for more than one antigenic determinant or that antigenic determinants recognized by T cells are shared widely and unexpectedly. It is not clear whether one or two different antigen receptors account for such dual reactivity. The nature of the T cell receptor for antigen remains obscure. T cell clones, because of their homogeneous nature, should make it easier to answer these important immunological questions. Although it remains to be determined how many distinct molecules account for the numerous biological activities found in the culture supernatants from antigen-stimulated T cell clones, it is clear that these factors influence several different types of cells that are involved directly and indirectly in immune responses. IL-2 stimulates both cytolytic and non-cytolytic T cells to proliferate. BCSF causes polyclonal activation of B cells, and there may be other factors which influence B cell responses to antigenic stimulation. IL-3 apparently stimulates maturation of immature T cells

  4. South American leaf blight of the rubber tree (Hevea spp.): new steps in plant domestication using physiological features and molecular markers.

    PubMed

    Lieberei, Reinhard

    2007-12-01

    Rubber trees (Hevea spp.) are perennial crops of Amazonian origin that have been spread over the whole tropical belt to guarantee worldwide production of natural rubber. This crop plant has found its place in many national economies of producing countries, and although its domestication by selection of suitable genotypes was very slow, it contributes a lot to the welfare of small farmers worldwide. Its development is limited by severe diseases. In South America, the main fungal disease of rubber trees is the South American leaf blight (SALB) caused by the ascomycete Microcyclus ulei. This fungus inhibits natural rubber production on a commercial scale in South and Central America. The disease is still restricted to its continent of origin, but its potential to be distributed around the world rises with every transcontinental airline connection that directly links tropical regions. The need to develop control measures against the disease is an urgent task and must be carried out on an international scale. All control efforts so far taken since 1910 have ended in a miserable failure. Even the use of modern systemic fungicides and use of greatly improved application techniques have failed to prevent large losses and dieback of trees. The results of research dealing with both the disease and the pathosystem over more than 50 years are summarized and placed into perspective. A detailed knowledge of this host-pathogen combination requires understanding of the dynamics of Hevea leaf development, the biochemical potential for cyanide liberation, and molecular data for several types of resistance factors. Resolution of the Hevea-SALB problem may serve as a model for future host-pathogen studies of perennial plants requiring a holistic approach.

  5. Mutants of Paracoccidioides brasiliensis strain IVIC Pb9 affected in dimorphism.

    PubMed

    San-Blas, F; San-Blas, G

    1992-01-01

    Morphological mutants were isolated after nitrosoguanidine treatment of Paracoccidioides brasiliensis strain IVIC Pb9. Two of these mutants, Pb257 and Pb258, developed a typical mycelia at 23 degrees C, however, the yeast cells which developed at 37 degrees C were indistinguishable from those of the parental strain. A third mutant, strain Pb267, was thermosensitive, grew as yeast-like cells at 23 degrees C, but was unable to survive at 37 degrees C. Morphological observations as well as serological and segregation tests confirmed that the mutant strains originated from P. brasiliensis. Cell wall chemical analyses of the mutant strains grown at 23 degrees C indicated the presence of alkali-soluble, acid-insoluble polysaccharides absent in the parental wild-type strain Pb9 grown under the same conditions. The phenotypes shown by the mutant strains may be related to deficiencies in the proper synthesis of cell wall components of the mycelial phase of this fungus.

  6. Killing of Paracoccidioides brasiliensis conidia by pulmonary macrophages and the effect of cytokines.

    PubMed

    Cano, L E; Arango, R; Salazar, M E; Brummer, E; Stevens, D A; Restrepo, A

    1992-01-01

    The ability of conidia, the infectious form of the dimorphic fungus Paracoccidioides brasiliensis, to be killed in vitro by murine pulmonary macrophages was studied. Mice were immunized by intravenous injection of killed conidia, which resulted in cellular immunity demonstrated by delayed type hypersensitivity in vivo and macrophage migration inhibition factor production in vitro. Resident pulmonary macrophages from non-immune mice were able to significantly kill the conidia (28%). Such macrophages treated with supernatants (cytokines) from antigen-stimulated immune mononuclears had a markedly enhanced ability to kill conidia (73%). These results show that activated pulmonary macrophages are potent killers of conidia of P. brasiliensis and that immune mononuclears play a role in activation of macrophages. Activated macrophages may be important for pulmonary defense against the initial stages of infection with this fungus.

  7. Annotated mitochondrial genome with Nanopore R9 signal for Nippostrongylus brasiliensis.

    PubMed

    Chandler, Jodie; Camberis, Mali; Bouchery, Tiffany; Blaxter, Mark; Le Gros, Graham; Eccles, David A

    2017-01-01

    Nippostrongylus brasiliensis, a nematode parasite of rodents, has a parasitic life cycle that is an extremely useful model for the study of human hookworm infection, particularly in regards to the induced immune response. The current reference genome for this parasite is highly fragmented with minimal annotation, but new advances in long-read sequencing suggest that a more complete and annotated assembly should be an achievable goal. We de-novo assembled a single contig mitochondrial genome from N. brasiliensis using MinION R9 nanopore data. The assembly was error-corrected using existing Illumina HiSeq reads, and annotated in full (i.e. gene boundary definitions without substantial gaps) by comparing with annotated genomes from similar parasite relatives. The mitochondrial genome has also been annotated with a preliminary electrical consensus sequence, using raw signal data generated from a Nanopore R9 flow cell.

  8. THE POWER OF THE SMALL: THE EXAMPLE OF Paracoccidioides brasiliensis CONIDIA

    PubMed Central

    RESTREPO, Angela; CANO, Luz Elena; GONZALEZ, Ángel

    2015-01-01

    SUMMARY Research on Paracoccidioides brasiliensis has centered in the yeast cell probably because of the lack of distinctive features in the mycelium. In 1942 and for the first time, lateral conidia were noticed in the fungus' hyphae. Later on, Brazilian, Venezuelan and Argentinean researchers described "aleurias" when the fungus was grown in natural substrates. In 1970 authors became interested in the conidia and were able to obtain them in large numbers and treat them as individual units. Their shape and size were defined and the presence of all the elements of a competent eukaryotic cell were demonstrated. Conidia exhibited thermal dimorphism and, additionally, when given intranasally to BALB/c male mice, they converted into yeasts in the lungs and produce progressive pulmonary lesions with further dissemination to other organs. Studies on the phagocyte-conidia interaction were revealing and showed that these versatile structures allow a better understanding of the host- P. brasiliensis interactions. PMID:26465363

  9. Immunoglobulin and complement in tissues of mice infected with Nocardia brasiliensis.

    PubMed Central

    Conde, C; Mancilla, R; Fresan, M; Ortiz-Ortiz, L

    1983-01-01

    Two weeks after mice had been infected in the footpad with cells of Nocardia brasiliensis, immunoglobulin and C3 deposits were observed in tissue from the inoculation site. Both immunoglobulin and C3 were found in the actinomycotic granules that characterize the mycetoma and in the surrounding inflammatory zones, in which plasma cells were also present. Although anti-N. brasiliensis specificity was evidenced at 14 days postinfection in an eluate of infected tissue by an immunoenzymatic assay, no such antibody was found in the serum until 45 days postinfection. Immune complexes in the lesions, as indicated by the presence of C3, may also contribute to the pathology of the disease. Images PMID:6852920

  10. Statistical based media optimization and production of naringinase using Aspergillus brasiliensis 1344.

    PubMed

    Shanmugaprakash, M; Kirthika, J; Ragupathy, J; Nilanee, K; Manickam, A

    2014-03-01

    Statistics based optimization, Plackett-Burman design (PBD) and response surface methodology (RSM) were employed to screen and optimize the media components for the production of naringinase from Aspergillus brasiliensis MTCC 1344, using solid state fermentation. Cassava waste (CW) was used as both the solid support and carbon source for the growth of A. brasiliensis. Based on the positive influence of the Pareto chart obtained from PBD on naringinase activity, three media components--maltose, peptone and calcium chloride were screened. Box-Behnken design (BBD) was employed using these three factors at three levels, for further optimization, and the second order polynomial equation was derived, based on the experimental data. Derringer's desired function methodology showed that the concentrations of maltose (7.74 g/L), peptone (4.19 g/L) and calcium chloride (7.63 mM) were the optimal levels for maximal naringinase activity (889.91 U/mg) which were validated through experiments.

  11. Biochemical differentiation of mycelium and yeast forms of Paracoccidioides brasiliensis by Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Castilho, Maiara L.; Campos, Claudia B. L.; Matos, Tatiana G. F.; de Abreu, Geraldo M. A.; Martin, Airton A.; Raniero, Leandro

    2012-01-01

    Paracoccidioides brasiliensis the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25 °C in vitro) and as yeast cells in the human host (or at 37°C in vitro). The most prominent difference between both forms is probably the cell wall polysaccharide, being 1,3-β-glucan usually found in mycelia and 1,3-α-glucan found in yeasts, but a plethora of other differences have already been described. In this work, we performed a Fourier Transform Infrared Spectroscopy analysis to compare the yeast and mycelia forms of P. brasiliensis and found additional biochemical differences. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates.

  12. Nocardia brasiliensis induces an immunosuppressive microenvironment that favors chronic infection in BALB/c mice.

    PubMed

    Rosas-Taraco, Adrian G; Perez-Liñan, Amira R; Bocanegra-Ibarias, Paola; Perez-Rivera, Luz I; Salinas-Carmona, Mario C

    2012-07-01

    Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P < 0.05) in footpad tissue and spleen. Treg subpopulations peaked at days 7 and 15 (P < 0.01) in the footpad and spleen, respectively. Transforming growth factor β1 (TGF-β1) and interleuki-10 (IL-10) are cytokines known for their immunosuppressive effects. During early and chronic infections, these cytokines were elevated with increased TGF-β1 levels from days 3 to 30 (P < 0.01) and sustained IL-10 expression throughout infection compared to uninfected mice. IL-6 production was increased at day 3 (P < 0.01), whereas gamma interferon (IFN-γ), IL-17A, and IL-23 levels were highest at day 15 postinfection (P < 0.01) when a decrease in the bacterial load (>1 log) was also observed (P < 0.05). After these changes, at 30 to 60 days postinfection, IFN-γ production was decreased, whereas the expression of anti-inflammatory cytokines and the bacterial load again increased (P < 0.05). The increment in Treg cells and the related cytokine profile correlated with reduced inflammation at day 15 (P < 0.05) in the footpad. We conclude that N. brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection.

  13. Transcriptome characterization of the dimorphic and pathogenic fungus Paracoccidioides brasiliensis by EST analysis.

    PubMed

    Felipe, M S S; Andrade, R V; Petrofeza, S S; Maranhão, A Q; Torres, F A G; Albuquerque, P; Arraes, F B M; Arruda, M; Azevedo, M O; Baptista, A J; Bataus, L A M; Borges, C L; Campos, E G; Cruz, M R; Daher, B S; Dantas, A; Ferreira, M A S V; Ghil, G V; Jesuino, R S A; Kyaw, C M; Leitão, L; Martins, C R; Moraes, L M P; Neves, E O; Nicola, A M; Alves, E S; Parente, J A; Pereira, M; Poças-Fonseca, M J; Resende, R; Ribeiro, B M; Saldanha, R R; Santos, S C; Silva-Pereira, I; Silva, M A S; Silveira, E; Simões, I C; Soares, R B A; Souza, D P; De-Souza, M T; Andrade, E V; Xavier, M A S; Veiga, H P; Venancio, E J; Carvalho, M J A; Oliveira, A G; Inoue, M K; Almeida, N F; Walter, M E M T; Soares, C M A; Brígido, M M

    2003-02-01

    Paracoccidioides brasiliensis is a pathogenic fungus that undergoes a temperature-dependent cell morphology change from mycelium (22 degrees C) to yeast (36 degrees C). It is assumed that this morphological transition correlates with the infection of the human host. Our goal was to identify genes expressed in the mycelium (M) and yeast (Y) forms by EST sequencing in order to generate a partial map of the fungus transcriptome. Individual EST sequences were clustered by the CAP3 program and annotated using Blastx similarity analysis and InterPro Scan. Three different databases, GenBank nr, COG (clusters of orthologous groups) and GO (gene ontology) were used for annotation. A total of 3,938 (Y = 1,654 and M = 2,274) ESTs were sequenced and clustered into 597 contigs and 1,563 singlets, making up a total of 2,160 genes, which possibly represent one-quarter of the complete gene repertoire in P. brasiliensis. From this total, 1,040 were successfully annotated and 894 could be classified in 18 functional COG categories as follows: cellular metabolism (44%); information storage and processing (25%); cellular processes-cell division, posttranslational modifications, among others (19%); and genes of unknown functions (12%). Computer analysis enabled us to identify some genes potentially involved in the dimorphic transition and drug resistance. Furthermore, computer subtraction analysis revealed several genes possibly expressed in stage-specific forms of P. brasiliensis. Further analysis of these genes may provide new insights into the pathology and differentiation of P. brasiliensis.

  14. P. brasiliensis Virulence Is Affected by SconC, the Negative Regulator of Inorganic Sulfur Assimilation

    PubMed Central

    Menino, João Filipe; Saraiva, Margarida; Gomes-Rezende, Jéssica; Sturme, Mark; Pedrosa, Jorge; Castro, António Gil; Ludovico, Paula; Goldman, Gustavo H.; Rodrigues, Fernando

    2013-01-01

    Conidia/mycelium-to-yeast transition of Paracoccidioidesbrasiliensis is a critical step for the establishment of paracoccidioidomycosis, a systemic mycosis endemic in Latin America. Thus, knowledge of the factors that mediate this transition is of major importance for the design of intervention strategies. So far, the only known pre-requisites for the accomplishment of the morphological transition are the temperature shift to 37°C and the availability of organic sulfur compounds. In this study, we investigated the auxotrophic nature to organic sulfur of the yeast phase of Paracoccidioides, with special attention to P. brasiliensis species. For this, we addressed the role of SconCp, the negative regulator of the inorganic sulfur assimilation pathway, in the dimorphism and virulence of this pathogen. We show that down-regulation of SCONC allows initial steps of mycelium-to-yeast transition in the absence of organic sulfur compounds, contrarily to the wild-type fungus that cannot undergo mycelium-to-yeast transition under such conditions. However, SCONC down-regulated transformants were unable to sustain yeast growth using inorganic sulfur compounds only. Moreover, pulses with inorganic sulfur in SCONC down-regulated transformants triggered an increase of the inorganic sulfur metabolism, which culminated in a drastic reduction of the ATP and NADPH cellular levels and in higher oxidative stress. Importantly, the down-regulation of SCONC resulted in a decreased virulence of P. brasiliensis, as validated in an in vivo model of infection. Overall, our findings shed light on the inability of P. brasiliensis yeast to rely on inorganic sulfur compounds, correlating its metabolism with cellular energy and redox imbalances. Furthermore, the data herein presented reveal SconCp as a novel virulence determinant of P. brasiliensis. PMID:24066151

  15. Isolation and antigenicity of a 45-kilodalton Paracoccidioides brasiliensis immunodominant antigen.

    PubMed Central

    Ferreira-da-Cruz, M F; Galvão-Castro, B; Daniel-Ribeiro, C

    1992-01-01

    In the present study, we analyzed human antibody responses to Paracoccidioides brasiliensis cellular antigens by the immunoblot technique to identify specific cellular components and to investigate the existence of antigen profile differences among serological responses of paracoccidioidomycosis (PCM) patients. Among the 64 PCM serum samples analyzed, a relatively homogeneous immunoglobulin G response to P. brasiliensis antigens was observed. The polypeptide with a mass of 45 kDa was the most clinically important, since antibody to this antigen was detectable in 90.6% of PCM patients studied and the six individuals who did not produce antibody were either at the end of treatment or in the posttherapy period and had shown clinical recovery. These facts suggested that the presence of this antibody may be an indicator of active disease. The 45-kDa antigen was also the most specific antigen of the PCM humoral immune response, since it reacted with only 2 of 79 (2.5%) heterologous serum samples tested: 1 histoplasmosis case and 1 tuberculosis case. This polypeptide was isolated from gels by electroelution and, when tested by an immunoradiometric assay and immunoblotting, maintained its reactivity with PCM sera and also with anti-P. brasiliensis polyclonal antibodies raised in rabbits at the same sensitivity levels as those obtained in immunoblotting with a crude antigen. Since in our assays the 45-kDa polypeptide was the major P. brasiliensis antigen and seemed to be specific for PCM, its use in alternative diagnostic methods is promising, especially in patients suspected of having the juvenile clinical form of PCM often associated with negative double-immunodiffusion results. Images PMID:1612736

  16. Isolation and antigenicity of a 45-kilodalton Paracoccidioides brasiliensis immunodominant antigen.

    PubMed

    Ferreira-da-Cruz, M F; Galvão-Castro, B; Daniel-Ribeiro, C

    1992-07-01

    In the present study, we analyzed human antibody responses to Paracoccidioides brasiliensis cellular antigens by the immunoblot technique to identify specific cellular components and to investigate the existence of antigen profile differences among serological responses of paracoccidioidomycosis (PCM) patients. Among the 64 PCM serum samples analyzed, a relatively homogeneous immunoglobulin G response to P. brasiliensis antigens was observed. The polypeptide with a mass of 45 kDa was the most clinically important, since antibody to this antigen was detectable in 90.6% of PCM patients studied and the six individuals who did not produce antibody were either at the end of treatment or in the posttherapy period and had shown clinical recovery. These facts suggested that the presence of this antibody may be an indicator of active disease. The 45-kDa antigen was also the most specific antigen of the PCM humoral immune response, since it reacted with only 2 of 79 (2.5%) heterologous serum samples tested: 1 histoplasmosis case and 1 tuberculosis case. This polypeptide was isolated from gels by electroelution and, when tested by an immunoradiometric assay and immunoblotting, maintained its reactivity with PCM sera and also with anti-P. brasiliensis polyclonal antibodies raised in rabbits at the same sensitivity levels as those obtained in immunoblotting with a crude antigen. Since in our assays the 45-kDa polypeptide was the major P. brasiliensis antigen and seemed to be specific for PCM, its use in alternative diagnostic methods is promising, especially in patients suspected of having the juvenile clinical form of PCM often associated with negative double-immunodiffusion results.

  17. Immunological characterization of a recombinant 27-kilodalton antigenic protein from Paracoccidioides brasiliensis.

    PubMed Central

    Ortiz, B L; Garcia, A M; Restrepo, A; McEwen, J G

    1996-01-01

    We report the expression in Escherichia coli of a 27-kDa antigenic protein from Paracoccidioides brasiliensis. When analyzed by immunoblotting, this recombinant antigenic protein was recognized by antibodies present in the sera of 40 of the 44 paracoccidioidomycosis patients studied. No cross-reactions were observed with sera from patients with other mycoses (histoplasmosis, aspergillosis, cryptococcosis, sporotrichosis, and chromoblastomycosis) or with tuberculosis. PMID:8991645

  18. High frequency of Paracoccidioides brasiliensis infection in armadillos (Dasypus novemcinctus): an ecological study.

    PubMed

    Bagagli, E; Franco, M; Bosco, S De M G; Hebeler-Barbosa, F; Trinca, L A; Montenegro, M R

    2003-06-01

    The fungus Paracoccidioides brasiliensis has been isolated from nine-banded armadillos (Dasypus novemcinctus) in different regions where paracoccidiodomycosis (PCM) is endemic. The link between PCM and these animals has provided the first valuable clue in the effort to elucidate the ecological niche of P. brasiliensis. The present study was aimed at correlating P. brasiliensis infection in armadillos with local ecological features and, if possible, the presence of the fungus in the soil in the Botucatu hyperendemic area of PCM. In this region the mean temperature ranges from 14.8 to 25.8 degrees C and the annual average precipitation is 1520 mm. The sites where 10 infected animals (positive group) were collected were studied and compared with the sites where five uninfected animals were found. The occurrence of the fungus in soil samples collected from the positive armadillos' burrows and foraging sites was investigated by the indirect method of animal inoculation. Environmental data from the sites of animal capture, such as temperature, rainfall, altitude, vegetation, soil composition, presence of water and proximity of urban areas, were recorded. All 37 soil samples collected from the sites had negative fungal cultures. Positive animals were found much more frequently in sites with disturbed vegetation, such as riparian forests and artificial Eucalyptus or Pinus forests, in altitudes below 800 m, near water sources. The soil type of the sites of positive animals was mainly sandy, with medium to low concentrations of organic matter. The pH was mainly acidic at all the sites, although the concentrations of aluminum cations (H+Al) were lower at the sites where positive animals were found. Positive armadillos were also captured in sites very close to urban areas. Our data and previous studies indicate that P. brasiliensis occurs preferentially in humid and shady disturbed forests in a strong association with armadillos.

  19. Nocardia brasiliensis Induces an Immunosuppressive Microenvironment That Favors Chronic Infection in BALB/c Mice

    PubMed Central

    Rosas-Taraco, Adrian G.; Perez-Liñan, Amira R.; Bocanegra-Ibarias, Paola; Perez-Rivera, Luz I.

    2012-01-01

    Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P < 0.05) in footpad tissue and spleen. Treg subpopulations peaked at days 7 and 15 (P < 0.01) in the footpad and spleen, respectively. Transforming growth factor β1 (TGF-β1) and interleuki-10 (IL-10) are cytokines known for their immunosuppressive effects. During early and chronic infections, these cytokines were elevated with increased TGF-β1 levels from days 3 to 30 (P < 0.01) and sustained IL-10 expression throughout infection compared to uninfected mice. IL-6 production was increased at day 3 (P < 0.01), whereas gamma interferon (IFN-γ), IL-17A, and IL-23 levels were highest at day 15 postinfection (P < 0.01) when a decrease in the bacterial load (>1 log) was also observed (P < 0.05). After these changes, at 30 to 60 days postinfection, IFN-γ production was decreased, whereas the expression of anti-inflammatory cytokines and the bacterial load again increased (P < 0.05). The increment in Treg cells and the related cytokine profile correlated with reduced inflammation at day 15 (P < 0.05) in the footpad. We conclude that N. brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection. PMID:22547544

  20. The pathogenic fungus Paracoccidioides brasiliensis exports extracellular vesicles containing highly immunogenic α-Galactosyl epitopes.

    PubMed

    Vallejo, Milene C; Matsuo, Alisson L; Ganiko, Luciane; Medeiros, Lia C Soares; Miranda, Kildare; Silva, Luiz S; Freymüller-Haapalainen, Edna; Sinigaglia-Coimbra, Rita; Almeida, Igor C; Puccia, Rosana

    2011-03-01

    Exosome-like vesicles containing virulence factors, enzymes, and antigens have recently been characterized in fungal pathogens, such as Cryptococcus neoformans and Histoplasma capsulatum. Here, we describe extracellular vesicles carrying highly immunogenic α-linked galactopyranosyl (α-Gal) epitopes in Paracoccidioides brasiliensis. P. brasiliensis is a dimorphic fungus that causes human paracoccidioidomycosis (PCM). For vesicle preparations, cell-free supernatant fluids from yeast cells cultivated in Ham's defined medium-glucose were concentrated in an Amicon ultrafiltration system and ultracentrifuged at 100,000 × g. P. brasiliensis antigens were present in preparations from phylogenetically distinct isolates Pb18 and Pb3, as observed in immunoblots revealed with sera from PCM patients. In an enzyme-linked immunosorbent assay (ELISA), vesicle components containing α-Gal epitopes reacted strongly with anti-α-Gal antibodies isolated from both Chagas' disease and PCM patients, with Marasmius oreades agglutinin (MOA) (a lectin that recognizes terminal α-Gal), but only faintly with natural anti-α-Gal. Reactivity was inhibited after treatment with α-galactosidase. Vesicle preparations analyzed by electron microscopy showed vesicular structures of 20 to 200 nm that were labeled both on the surface and in the lumen with MOA. In P. brasiliensis cells, components carrying α-Gal epitopes were found distributed on the cell wall, following a punctuated confocal pattern, and inside large intracellular vacuoles. Lipid-free vesicle fractions reacted with anti-α-Gal in ELISA only when not digested with α-galactosidase, while reactivity with glycoproteins was reduced after β-elimination, which is indicative of partial O-linked chain localization. Our findings open new areas to explore in terms of host-parasite relationships in PCM and the role played in vivo by vesicle components and α-galactosyl epitopes.

  1. [Comparative study of the pathogenicity and antigenicity of 6 Paracoccidioides brasiliensis strains].

    PubMed

    Finquelievich, J L; Negroni, R; Iovannitti, C A; de Elías Costa, M R

    1993-01-01

    A comparative study of antigenicity and pathogenicity for rats of six Paracoccidioides brasiliensis strains was carried out. The antigenic capacity "in vitro" of cytoplasmic extract from each strain was determined by immunodiffusion test against 6 serum samples obtained from rats experimentally infected with Paracoccidioides brasiliensis, that had presented positive reactions with a metabolic control antigen. The cytoplasmic extracts were used at final concentration of 100 mg/ml. All of them showed 2 or 3 precipitation bands in this assay. One hundred twenty Wistar rats both sexes weighing approximately 200 g, were inoculated intracardiacally with suspensions of the yeast phase of different P. brasiliensis strains. Two concentrations containing 3 x 10(7) and 5 x 10(7) cells/ml of each isolate were prepared. The inoculated animals were divided in two groups, one was left to its spontaneous outcome and the percentages of deaths were registered and the other rats were sacrificed at 14, 28, 56 and 70 days post-infection. The following parameters were taken into account for evaluation: A) presence of macroscopic granulomas in lung, liver, spleen and kidney; B) presence of P. brasiliensis in microscopic exams of the same organs, in wet preparations and in histologic sections stained by H&E; C) culture of lung and D) immunodiffusion test using pre-mortem serum samples and the homologous antigen. The correlation between the most important parameters studied in each strain are summarized as follow: As no significant differences between the two inocula employed for each strain was observed, the before mention results are the average of those obtained with each inoculation doses.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Caspofungin Affects Growth of Paracoccidioides brasiliensis in Both Morphological Phases ▿ †

    PubMed Central

    Rodríguez-Brito, Sabrina; Niño-Vega, Gustavo; San-Blas, Gioconda

    2010-01-01

    Five Paracoccidioides brasiliensis isolates were grown in the presence of caspofungin (0 to 1 μg/ml). Inhibition of the yeast phase ranged from 20 to 65%, while in the mycelial form it ranged from 75% to 82%. Such variability was loosely related to the amount of cell wall β-1,3-glucan. No association with point mutations in the β-1,3-glucan synthase was detected. Caspofungin induced physical changes and cytoplasmic deterioration in both fungal phases. PMID:20937789

  3. Brasilinolide A, a new macrolide antibiotic produced by Nocardia brasiliensis: producing strain, isolation and biological activity.

    PubMed

    Tanaka, Y; Komaki, H; Yazawa, K; Mikami, Y; Nemoto, A; Tojyo, T; Kadowaki, K; Shigemori, H; Kobayashi, J

    1997-12-01

    A new 32-membered macrolide antibiotic, brasilinolide A was isolated from the fermentation broth of Nocardia sp. IFM 0406. The producer was identified as Nocardia brasiliensis. The antibiotic was only active against Aspergillus niger, but not active against other fungi including yeasts as well as other filamentous like fungi and bacteria. Brasilinolide A exerted an immunosuppressive activity in the assay system of a mixed lymphocyte reaction (MLR).

  4. Potential for cloning dogs.

    PubMed

    Westhusin, M E; Burghardt, R C; Ruglia, J N; Willingham, L A; Liu, L; Shin, T; Howe, L M; Kraemer, D C

    2001-01-01

    The aim of this study was to determine whether nuclear transplantation could be used to clone a dog using donor nucleus cells collected from an adult female. Fibroblasts obtained from skin biopsies were fused with enucleated bovine or canine oocytes. The resulting cloned embryos were cultured in vitro to monitor embryonic development. A proportion of the resulting embryos was transferred into surrogate bitches for development to term. When canine oocytes were used as recipient ova for canine fibroblasts, 23% of the resulting embryos cleaved at least once after culture in vitro. Five cloned embryos were transferred into three synchronized recipient bitches, but no pregnancies resulted. When bovine oocytes were used as recipinets for canine fibroblasts, 38% cleaved to the two- to four-cell stage and 43% cleaved to the eight- to 16-cell stage. Forty-seven of these embryos were transferred into four recipient females, resulting in a single conceptus that ceased development at about day 20 of gestation. The desire for cloned dogs is considerable and will undoubtedly incite the development of successful methods for cloning companion animals. However, significant investment into additional research is required, especially in the areas of in vitro maturation of oocytes and control of the oestrous cycle of bitches.

  5. Comparison of virulence between Paracoccidioides brasiliensis and Paracoccidioides lutzii using Galleria mellonella as a host model

    PubMed Central

    Scorzoni, Liliana; de Paula e Silva, Ana Carolina Alves; Singulani, Junya de Lacorte; Leite, Fernanda Sangalli; de Oliveira, Haroldo Cesar; Moraes da Silva, Rosangela Aparecida; Fusco-Almeida, Ana Marisa; Mendes-Giannini, Maria José Soares

    2015-01-01

    Paracoccidioidomycosis is a systemic mycosis, endemic in Latin America. The etiologic agents of this mycosis are composed of 2 species: Paracoccidioides brasiliensis and P. lutzii. Murine animal models are the gold standard for in vivo studies; however, ethical, economical and logistical considerations limit their use. Galleria mellonella is a suitable model for in vivo studies of fungal infections. In this study, we compared the virulence of P. brasiliensis and P. lutzii in G. mellonella model. The deaths of larvae infected with P. brasiliensis or P. lutzii were similar, and both species were able to reduce the number of hemocytes, which were estimated by microscopy and flow cytometer. Additionally, the phagocytosis percentage was similar for both species, but when we analyze hemocyte-Paracoccidioides spp. interaction using flow cytometer, P. lutzii showed higher interactions with hemocytes. The gene expression of gp43 as well as this protein was higher for P. lutzii, and this expression may contribute to a greater adherence to hemocytes. These results helped us evaluate the behavior of Paracoccidioides spp in G. mellonella, which is a convenient model for investigating the host-Paracoccidioides spp. interaction. PMID:26552324

  6. In vitro Paracoccidioides brasiliensis biofilm and gene expression of adhesins and hydrolytic enzymes

    PubMed Central

    Sardi, Janaina de Cássia Orlandi; Pitangui, Nayla de Souza; Voltan, Aline Raquel; Braz, Jaqueline Derissi; Machado, Marcelo Pelajo; Fusco Almeida, Ana Marisa; Mendes Giannini, Maria Jose Soares

    2015-01-01

    Paracoccidioides species are dimorphic fungi that initially infect the lungs but can also spread throughout the body. The spreading infection is most likely due to the formation of a biofilm that makes it difficult for the host to eliminate the infection. Biofilm formation is crucial for the development of infections and confines the pathogen to an extracellular matrix. Its presence is associated with antimicrobial resistance and avoidance of host defenses. This current study provides the first description of biofilm formation by Paracoccidioides brasiliensis (Pb18) and an analysis of gene expression, using real-time PCR, associated with 3 adhesins and 2 hydrolytic enzymes that could be associated with the virulence profile. Biofilm formation was analyzed using fluorescence microscopy, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Metabolic activity was determined using the XTT reduction assay. P. brasiliensis was able to form mature biofilm in 144 h with a thickness of 100 μm. The presence of a biofilm was found to be associated with an increase in the expression of adhesins and enzymes. GP43, enolase, GAPDH and aspartyl proteinase genes were over-expressed, whereas phospholipase was down-regulated in biofilm. The characterization of biofilm formed by P. brasiliensis may contribute to a better understanding of the pathogenesis of paracoccidioidomycosis as well as the search for new therapeutic alternatives; while improving the effectiveness of treatment. PMID:26055497

  7. Paracoccidioides brasiliensis interacts with dermal dendritic cells and keratinocytes in human skin and oral mucosa lesions.

    PubMed

    Silva, Wellington Luiz Ferreira da; Pagliari, Carla; Duarte, Maria Irma Seixas; Sotto, Mirian N

    2016-05-01

    Paracoccidioidomycosis (PCM) is a systemic disease caused by the fungus Paracoccidioides brasiliensis and Paracoccidioides lutzii. In PCM the skin and oral mucosa are often affected. Dendritic cells and keratinocytes of the integument play a role in innate and adaptive immune response against pathogens, due to their function as antigen presenting cells. Aiming to verify the interaction of P. brasiliensis with these cell populations, we studied 52 skin and 47 oral mucosa samples taken from patients with proven diagnosis of PCM. The biopsies were subjected to immunohistochemical and/or immunofluorescence staining with anti-factor XIIIa (marker of dermal dendrocytes), anti-CD207 (marker of mature Langerhans cells), anti-pan cytokeratins (AE1-AE3) and anti-P. brasiliensis antibodies. Analyses with confocal laser microscopy were also performed for better visualization of the interaction between keratinocytes and the fungi. In sum, 42% of oral mucosa samples displayed yeast forms in Factor XIIIa dermal dendrocytes cytoplasm. Langerhans cells in skin and oral mucosa samples did not show yeast cells in their cytoplasm. In sum, 54% of skin and 60% of mucosal samples displayed yeast cells in the cytoplasm of keratinocytes. The parasitism of keratinocytes may represent a possible mechanism of evasion of the fungus to local immune mechanisms. Factor XIIIa dendrocytes and keratinocytes may be acting as antigen-presenting cells to fulfill the probably impaired function of Langerhans cells in skin and oral mucosa of human PCM.

  8. An Hcp100 gene fragment reveals Histoplasma capsulatum presence in lungs of Tadarida brasiliensis migratory bats.

    PubMed

    González-González, A E; Aliouat-Denis, C M; Carreto-Binaghi, L E; Ramírez, J A; Rodríguez-Arellanes, G; Demanche, C; Chabé, M; Aliouat, E M; Dei-Cas, E; Taylor, M L

    2012-11-01

    Histoplasma capsulatum was sampled in lungs from 87 migratory Tadarida brasiliensis bats captured in Mexico (n=66) and Argentina (n=21). The fungus was screened by nested-PCR using a sensitive and specific Hcp100 gene fragment. This molecular marker was detected in 81·6% [95% confidence interval (CI) 73·4-89·7] of all bats, representing 71 amplified bat lung DNA samples. Data showed a T. brasiliensis infection rate of 78·8% (95% CI 68·9-88·7) in bats captured in Mexico and of 90·4% (95% CI 75·2-100) in those captured in Argentina. Similarity with the H. capsulatum sequence of a reference strain (G-217B) was observed in 71 Hcp100 sequences, which supports the fungal findings. Based on the neighbour-joining and maximum parsimony Hcp100 sequence analyses, a high level of similarity was found in most Mexican and all Argentinean bat lung samples. Despite the fact that 81·6% of the infections were molecularly evidenced, only three H. capsulatum isolates were cultured from all samples tested, suggesting a low fungal burden in lung tissues that did not favour fungal isolation. This study also highlighted the importance of using different tools for the understanding of histoplasmosis epidemiology, since it supports the presence of H. capsulatum in T. brasiliensis migratory bats from Mexico and Argentina, thus contributing new evidence to the knowledge of the environmental distribution of this fungus in the Americas.

  9. Preserving and Maintaining Culinary-Medicinal Royal Sun Mushroom, Agaricus brasiliensis (Agaricomycetes), in Sterile Distilled Water.

    PubMed

    Vargas-Del-Rlo, L M; Montoya, Sandra; Sepulveda-Arias, J C

    2017-01-01

    Strains of Agaricus brasiliensis require special procedures for conservation. Thus, the objective of this research was to establish conservation and maintenance procedures A. brasiliensis strain PSWC838 from the University of Pennsylvania (ABWC838) and an A. brasiliensis strain from the Fujian Agriculture and Forestry University (ABC). The medium in which mycelia grew the quickest for both strains was selected using a multifactorial design with 2 strains, 4 culture media, and incubation for 5 different times; the growth rate (mm/day) was the response variable. Analysis of variance showed that the potato dextrose agar (PDA) medium and potato extract did not display a significantly different growth rate, and PDA was selected for safety reasons. We also evaluated the viability of the strains grown on PDA and 0.2% activated carbon after 3 months of storage in sterile distilled water. A factorial design was applied with 2 factors, the strain and incubation for 10 different times. The Tukey post hoc test indicated that ABC showed quicker and more homogeneous growth than ABWC838. Finally, the results showed that pieces of mycelium of ABC and ABWC838 strains inoculated on the PDA medium with 0.2% activated carbon and preserved in sterile distilled water at 18 ± 1°C showed 100% viability after 3 months of storage. Moreover, the results of semiquantitative biochemical tests confirmed that the production of laccases and amylases was preserved in these strains after storage in sterile water, enhancing their ability to degrade substrates containing lignin and starchy waste.

  10. Identification, N-terminal region sequencing and similarity analysis of differentially expressed proteins in Paracoccidioides brasiliensis.

    PubMed

    Cunha, A F; Sousa, M V; Silva, S P; Jesuíno, R S; Soares, C M; Felipe, M S

    1999-04-01

    Paracoccidioides brasiliensis is the causal agent of paracoccidioidomycosis, which is a systemic mycosis in Latin America. This human pathogen is a dimorphic fungus existing as mycelium (26 degrees C) and in infected tissues as a yeast form (36 degrees C). The in vitro differentiation process is reversible and dependent on temperature shift. In the present study, the total proteins from both forms of P. brasiliensis (isolate Pb01) were analysed by two-dimensional electrophoresis. Differentially expressed proteins were identified. Two of these proteins, PbM46 (mycelium) and PbY20 (yeast), were submitted to automated protein sequencing of their N-terminal regions. The 15 amino acid residue sequence of PbM46, AITKIFALKVYDSSG, is similar to enolases from several sources, and specially those from Saccharomyces cerevisiae (80%) and Candida albicans (67%), when compared to the NR database at NCBI using the BLASTP program. The 34 amino acid residue sequence of PbY20, APKIAIVFYSLYGHIQKLAEAQKKGIEAAGGTAD, could probably represent an allergen protein since it is very similar (90%) to the minor allergen protein of Alternaria alternata and 82% similar to the allergen protein of Cladosporium herbarum. This comparative analysis of proteins from mycelium and yeast forms has allowed the identification and characterization of differentially expressed proteins, probably related to differential gene expression in P. brasiliensis.

  11. Insights into the plant polysaccharide degradation potential of the xylanolytic yeast Pseudozyma brasiliensis.

    PubMed

    Kaupert Neto, Antonio Adalberto; Borin, Gustavo Pagotto; Goldman, Gustavo Henrique; Damásio, André Ricardo de Lima; Oliveira, Juliana Velasco de Castro

    2016-03-01

    In second-generation (2G) bioethanol production, plant cell-wall polysaccharides are broken down to release fermentable sugars. The enzymes of this process are classified as carbohydrate-active enzymes (CAZymes) and contribute substantially to the cost of biofuel production. A novel basidiomycete yeast species, Pseudozyma brasiliensis, was recently discovered. It produces an endo-β-1,4-xylanase with a higher specific activity than other xylanases. This enzyme is essential for the hydrolysis of biomass-derived xylan and has an important role in 2G bioethanol production. In spite of the P. brasiliensis biotechnological potential, there is no information about how it breaks down polysaccharides. For the first time, we characterized the secretome of P. brasiliensis grown on different carbon sources (xylose, xylan, cellobiose and glucose) and also under starvation conditions. The growth and consumption of each carbohydrate and the activity of the CAZymes of culture supernatants were analyzed. The CAZymes found in its secretomes, validated by enzymatic assays, have the potential to hydrolyze xylan, mannan, cellobiose and other polysaccharides. The data show that this yeast is a potential source of hydrolases, which can be used for biomass saccharification.

  12. In Vitro Susceptibility of Sporothrix brasiliensis to Essential Oils of Lamiaceae Family.

    PubMed

    Waller, Stefanie Bressan; Madrid, Isabel Martins; Silva, Anna Luiza; Dias de Castro, Luciana Laitano; Cleff, Marlete Brum; Ferraz, Vanny; Meireles, Mário Carlos Araújo; Zanette, Régis; de Mello, João Roberto Braga

    2016-12-01

    This study evaluated the chemical, cytotoxic and anti-Sporothrix brasiliensis properties of commercial essential oils of rosemary (Rosmarinus officinalis L.), oregano (Origanum vulgare L.) and marjoram (Origanum majorana L.). Chemical composition of the oils was identified through gas chromatography with flame ionization detector, and cytotoxicity was performed through MTT assay in VERO cell line. Anti-S. brasiliensis activity was performed according to the CLSI M38-A2 guidelines using isolates obtained from cats and dogs. The major compounds found were carvacrol in the oregano oil (73.9 %) and 1,8-cineole in rosemary and marjoram oils (49.4 and 20.9 %, respectively). All S. brasiliensis isolates were susceptible to the plant oils, including itraconazole-resistant ones. Marjoram and rosemary oils showed MIC90 of 0.56 and 1.12 mg ml(-1), and MFC90 of 4.5 and 9 mg ml(-1), respectively. For oregano oil, a strong antifungal activity was observed with MIC90 and MFC90 values ≤0.07 mg ml(-1). The weakest cytotoxicity was observed for rosemary oil. Further studies should be undertaken to evaluate the safety and efficacy of these essential oils in sporotrichosis.

  13. Morphometry, Bite-Force, and Paleobiology of the Late Miocene Caiman Purussaurus brasiliensis

    PubMed Central

    Aureliano, Tito; Ghilardi, Aline M.; Guilherme, Edson; Souza-Filho, Jonas P.; Cavalcanti, Mauro; Riff, Douglas

    2015-01-01

    Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force). The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts. PMID:25689140

  14. Ecotope effect in Triatoma brasiliensis (Hemiptera: Reduviidae) suggests phenotypic plasticity rather than adaptation.

    PubMed

    Batista, V S P; Fernandes, F A; Cordeiro-Estrela, P; Sarquis, O; Lima, M M

    2013-09-01

    Triatoma brasiliensis (Hemiptera: Reduviidae) is an important vector of Chagas' disease in both sylvatic and peridomestic ecotopes. Discriminating between these populations of Triatominae has been proposed as a means of investigating re-infestation rates of human dwellings. Geometric morphometrics have been widely applied in the study of Triatominae polymorphisms at species and population levels. This study characterizes morphometric differences between sylvatic and peridomestic populations, as well as between sexes in T. brasiliensis specimens from Jaguaruana, Ceará, in northeastern Brazil. No differences in either the shape or size of the cephalic capsule were apparent between sexes or ecotopes. However, the wings showed differentiation in shape and size. Sexual dimorphism was detected, with females presenting significantly higher values and conformations. Size differentiation was also evident, with sylvatic specimens being generally larger than peridomestic examples. These results indicate that differences in the wings of T. brasiliensis may be related to the existence of phenotypic plasticity, and variations in size and shape may be associated with different ecotopes, possibly as a result of conditions in each micro-habitat, such as temperature, relative humidity, food supply and density. © 2012 The Royal Entomological Society.

  15. Virulence profiles of ten Paracoccidioides brasiliensis isolates obtained from armadillos (Dasypus novemcinctus).

    PubMed

    Hebeler-Barbosa, F; Montenegro, M R; Bagagli, E

    2003-04-01

    Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), the most important systemic mycosis in Latin America. The armadillo, Dasypus novemcinctus, has been confirmed as the primary natural reservoir of this fungus. Its geographic distribution is similar to that of human PCM. In this study, virulence profiles of 10 P. brasiliensis isolates from different armadillos and of two clinical isolates were tested in an experimental hamster model. Pathogenicity was evaluated by counting cfu and performing histopathological analysis in the testis, liver, spleen and lung. Circulating specific antibodies were measured using enzyme-linked immunosorbent assay (ELISA). All isolates from armadillos were virulent in the model, with dissemination to many organs. The clinical isolates, which had long been stored in cultured collections, were less virulent. The isolates were classified into four virulence categories according to number of cfu per gram of tissue: very high, high, intermediate and low. This study confirms that armadillos harbor pathogenic genotypes of P. brasiliensis, probably the same ones that infect humans.

  16. Development of pulmonary fibrosis in mice during infection with Paracoccidioides brasiliensis conidia.

    PubMed

    Restrepo, S; Tobon, A; Trujillo, J; Restrepo, A

    1992-01-01

    Pulmonary fibrosis is a feared sequelae of paracoccidioidomycosis. We sought to determine if mice exposed to Paracoccidioides brasiliensis conidia would develop pulmonary fibrosis. BALB/c mice were infected intranasally with P. brasiliensis conidia and sacrificed at regular intervals. One lung was sectioned for histopathology and sections were stained with haematoxylin and eosin, trichromic and argentic stains; the other lung was homogenized and cultured to determine the viability of the fungus. One week post-challenge, only small peribronchial foci were apparent. After 4 weeks, reticular fibres appeared disorganized and disrupted. Six to 8 weeks later peribronchial infiltrates were larger and appeared surrounded by reticular fibres; thick collagen I fibres were noticed in the infiltrated areas at this time. On weeks 10-12, infiltrates were confluent and reticular fibres were concentrated around the inflammatory foci; collagenization was apparent. Observations up to 16 weeks revealed diffuse involvement of the lung parenchyma with extensive collagenization. Lung cultures were always positive. We suggest that inhalation of P. brasiliensis conidia induces adverse lung responses leading to changes in the proportion of collagen fibres I and III.

  17. Nocardia brasiliensis Induces Formation of Foamy Macrophages and Dendritic Cells In Vitro and In Vivo

    PubMed Central

    Meester, Irene; Rosas-Taraco, Adrian Geovanni; Salinas-Carmona, Mario Cesar

    2014-01-01

    Foamy cells have been described in various infectious diseases, for example in actinomycetoma induced by Nocardia brasiliensis. These cells are generally considered to be macrophages, although they present dendritic cell (DC)-specific surface markers. In this study, we determined and confirmed the lineage of possible precursors of foamy cells in vitro and in vivo using an experimental actinomycetoma model in BALB/c mice. Bone marrow-derived macrophages (BMDM) or DC (BMDC) were infected in vitro with N. brasiliensis or labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). Both, macrophages and DC, differentiated into foamy cells after in vitro infection. CFSE-labeled BMDM or BMDC were tested for phagocytosis and CD11c/CD11b receptors markers expression before being transferred into the actinomycetoma lesion site of infected mice. In vivo studies showed that BMDM and BMDC were traced at the site where foamy cells are present in the experimental actinomycetoma. Interestingly, many of the transferred BMDM and BMDC were stained with the lipid-droplet fluorophore Nile Red. In conclusion, macrophages and DC cells can be differentiated into foamy cells in vitro and in vivo during N. brasiliensis infection. PMID:24936860

  18. Comparison of virulence between Paracoccidioides brasiliensis and Paracoccidioides lutzii using Galleria mellonella as a host model.

    PubMed

    Scorzoni, Liliana; de Paula e Silva, Ana Carolina Alves; Singulani, Junya de Lacorte; Leite, Fernanda Sangalli; de Oliveira, Haroldo Cesar; da Silva, Rosangela Aparecida Moraes; Fusco-Almeida, Ana Marisa; Mendes-Giannini, Maria José Soares

    2015-01-01

    Paracoccidioidomycosis is a systemic mycosis, endemic in Latin America. The etiologic agents of this mycosis are composed of 2 species: Paracoccidioides brasiliensis and P. lutzii. Murine animal models are the gold standard for in vivo studies; however, ethical, economical and logistical considerations limit their use. Galleria mellonella is a suitable model for in vivo studies of fungal infections. In this study, we compared the virulence of P. brasiliensis and P. lutzii in G. mellonella model. The deaths of larvae infected with P. brasiliensis or P. lutzii were similar, and both species were able to reduce the number of hemocytes, which were estimated by microscopy and flow cytometer. Additionally, the phagocytosis percentage was similar for both species, but when we analyze hemocyte-Paracoccidioides spp. interaction using flow cytometer, P. lutzii showed higher interactions with hemocytes. The gene expression of gp43 as well as this protein was higher for P. lutzii, and this expression may contribute to a greater adherence to hemocytes. These results helped us evaluate the behavior of Paracoccidioides spp in G. mellonella, which is a convenient model for investigating the host-Paracoccidioides spp. interaction.

  19. Antioxidant Effects of Medicinal Mushrooms Agaricus brasiliensis and Ganoderma lucidum (Higher Basidiomycetes): Evidence from Animal Studies.

    PubMed

    Yurkiv, Borys; Wasser, Solomon P; Nevo, Eviatar; Sybirna, Nataliya O

    2015-01-01

    With diabetes mellitus and increased glucose concentrations, the mitochondria electron transport chain is disrupted, superoxide anions are overproduced, and oxidative stress develops in cells. Thus, preventing oxidative stress can produce a decrease in the antioxidant system activity and an increase in apoptosis in immune cells. The application of medicinal mushrooms is a new possible approach to diabetes mellitus treatment. Therefore, the aim of this work was to investigate the influence of administration of the medicinal mushrooms Agaricus brasiliensis and Ganoderma lucidum on antioxidant enzyme activity in rat leukocytes. Wistar outbred white rats were used in the study. Streptozotocin was intraperitoneally injected once at a dose of 50 mg/kg body weight. Mushroom preparations were orally administered at a dose of 1 g/kg/day for 2 weeks. This revealed that in diabetes mellitus, the level of antioxidant enzyme activity is significantly decreased compared with control values, whereas the levels of lipid peroxidation is increased; this manifested in an increase in the amount of thiobarbituric acid reactive substances (TBARS). The medicinal mushrooms' administration is accompanied by an increase in antioxidant enzyme activity to control values and is even higher in the case of A. brasiliensis administration when compared with the diabetic group. As for the indicators of lipid peroxidation under mushroom administration of A. brasiliensis and G. lucidum, we observed a significant decrease of TBARS levels compared with the diabetic group. Increased activity of antioxidant enzymes and reduction of TBARS level indicate pronounced antioxidant properties of studied mushrooms.

  20. Nocardia brasiliensis Cell Wall Lipids Modulate Macrophage and Dendritic Responses That Favor Development of Experimental Actinomycetoma in BALB/c Mice

    PubMed Central

    Trevino-Villarreal, J. Humberto; Vera-Cabrera, Lucio; Valero-Guillén, Pedro L.

    2012-01-01

    Nocardia brasiliensis is a Gram-positive facultative intracellular bacterium frequently isolated from human actinomycetoma. However, the pathogenesis of this infection remains unknown. Here, we used a model of bacterial delipidation with benzine to investigate the role of N. brasiliensis cell wall-associated lipids in experimental actinomycetoma. Delipidation of N. brasiliensis with benzine resulted in complete abolition of actinomycetoma without affecting bacterial viability. Chemical analyses revealed that trehalose dimycolate and an unidentified hydrophobic compound were the principal compounds extracted from N. brasiliensis with benzine. By electron microscopy, the extracted lipids were found to be located in the outermost membrane layer of the N. brasiliensis cell wall. They also appeared to confer acid-fastness. In vitro, the extractable lipids from the N. brasiliensis cell wall induced the production of the proinflammatory cytokines interleukin-1β (IL-1β), IL-6, and CCL-2 in macrophages. The N. brasiliensis cell wall extractable lipids inhibited important macrophage microbicidal effects, such as tumor necrosis factor alpha (TNF-α) and nitric oxide (NO) production, phagocytosis, bacterial killing, and major histocompatibility complex class II (MHC-II) expression in response to gamma interferon (IFN-γ). In dendritic cells (DCs), N. brasiliensis cell wall-associated extractable lipids suppressed MHC-II, CD80, and CD40 expression while inducing tumor growth factor β (TGF-β) production. Immunization with delipidated N. brasiliensis induced partial protection preventing actinomycetoma. These findings suggest that N. brasiliensis cell wall-associated lipids are important for actinomycetoma development by inducing inflammation and modulating the responses of macrophages and DCs to N. brasiliensis. PMID:22851755

  1. Environmental controls in the water use patterns of a tropical cloud forest tree species, Drimys brasiliensis (Winteraceae).

    PubMed

    Eller, Cleiton B; Burgess, Stephen S O; Oliveira, Rafael S

    2015-04-01

    Trees from tropical montane cloud forest (TMCF) display very dynamic patterns of water use. They are capable of downwards water transport towards the soil during leaf-wetting events, likely a consequence of foliar water uptake (FWU), as well as high rates of night-time transpiration (Enight) during drier nights. These two processes might represent important sources of water losses and gains to the plant, but little is known about the environmental factors controlling these water fluxes. We evaluated how contrasting atmospheric and soil water conditions control diurnal, nocturnal and seasonal dynamics of sap flow in Drimys brasiliensis (Miers), a common Neotropical cloud forest species. We monitored the seasonal variation of soil water content, micrometeorological conditions and sap flow of D. brasiliensis trees in the field during wet and dry seasons. We also conducted a greenhouse experiment exposing D. brasiliensis saplings under contrasting soil water conditions to deuterium-labelled fog water. We found that during the night D. brasiliensis possesses heightened stomatal sensitivity to soil drought and vapour pressure deficit, which reduces night-time water loss. Leaf-wetting events had a strong suppressive effect on tree transpiration (E). Foliar water uptake increased in magnitude with drier soil and during longer leaf-wetting events. The difference between diurnal and nocturnal stomatal behaviour in D. brasiliensis could be attributed to an optimization of carbon gain when leaves are dry, as well as minimization of nocturnal water loss. The leaf-wetting events on the other hand seem important to D. brasiliensis water balance, especially during soil droughts, both by suppressing tree transpiration (E) and as a small additional water supply through FWU. Our results suggest that decreases in leaf-wetting events in TMCF might increase D. brasiliensis water loss and decrease its water gains, which could compromise its ecophysiological performance and survival

  2. Extremal quantum cloning machines

    NASA Astrophysics Data System (ADS)

    Chiribella, G.; D'Ariano, G. M.; Perinotti, P.; Cerf, N. J.

    2005-10-01

    We investigate the problem of cloning a set of states that is invariant under the action of an irreducible group representation. We then characterize the cloners that are extremal in the convex set of group covariant cloning machines, among which one can restrict the search for optimal cloners. For a set of states that is invariant under the discrete Weyl-Heisenberg group, we show that all extremal cloners can be unitarily realized using the so-called double-Bell states, whence providing a general proof of the popular ansatz used in the literature for finding optimal cloners in a variety of settings. Our result can also be generalized to continuous-variable optimal cloning in infinite dimensions, where the covariance group is the customary Weyl-Heisenberg group of displacements.

  3. Extremal quantum cloning machines

    SciTech Connect

    Chiribella, G.; D'Ariano, G. M.; Perinotti, P.; Cerf, N.J.

    2005-10-15

    We investigate the problem of cloning a set of states that is invariant under the action of an irreducible group representation. We then characterize the cloners that are extremal in the convex set of group covariant cloning machines, among which one can restrict the search for optimal cloners. For a set of states that is invariant under the discrete Weyl-Heisenberg group, we show that all extremal cloners can be unitarily realized using the so-called double-Bell states, whence providing a general proof of the popular ansatz used in the literature for finding optimal cloners in a variety of settings. Our result can also be generalized to continuous-variable optimal cloning in infinite dimensions, where the covariance group is the customary Weyl-Heisenberg group of displacement000.

  4. Functional characterization of NAT/NCS2 proteins of Aspergillus brasiliensis reveals a genuine xanthine-uric acid transporter and an intrinsically misfolded polypeptide.

    PubMed

    Krypotou, Emilia; Scazzocchio, Claudio; Diallinas, George

    2015-02-01

    The Nucleobase-Ascorbate Transporter (NAT) family includes members in nearly all domains of life. Functionally characterized NAT transporters from bacteria, fungi, plants and mammals are ion-coupled symporters specific for the uptake of purines, pyrimidines and related analogues. The characterized mammalian NATs are specific for the uptake of L-ascorbic acid. In this work we identify in silico a group of fungal putative transporters, named UapD-like proteins, which represent a novel NAT subfamily. To understand the function and specificity of UapD proteins, we cloned and functionally characterized the two Aspergillus brasiliensis NAT members (named AbUapC and AbUapD) by heterologous expression in Aspergillus nidulans. AbUapC represents canonical NATs (UapC or UapA), while AbUapD represents the new subfamily. AbUapC is a high-affinity, high-capacity, H(+)/xanthine-uric acid transporter, which can also recognize other purines with very low affinity. No apparent transport function could be detected for AbUapD. GFP-tagging showed that, unlike AbUapC which is localized in the plasma membrane, AbUapD is ER-retained and degraded in the vacuoles, a characteristic of misfolded proteins. Chimeric UapA/AbUapD molecules are also turned-over in the vacuole, suggesting that UapD includes intrinsic peptidic sequences leading to misfolding. The possible evolutionary implication of such conserved, but inactive proteins is discussed.

  5. To clone alone: the United Nations' Human Cloning Declaration.

    PubMed

    Isasi, Rosario M; Annas, George J

    2006-01-01

    The United Nations labored for almost four years to create a treaty governing human cloning. In 2005 that effort was abandoned, and instead the United Nations' General Assembly adopted a "Declaration on Human Cloning".

  6. rPbPga1 from Paracoccidioides brasiliensis Activates Mast Cells and Macrophages via NFkB.

    PubMed

    Valim, Clarissa Xavier Resende; da Silva, Elaine Zayas Marcelino; Assis, Mariana Aprigio; Fernandes, Fabricio Freitas; Coelho, Paulo Sergio Rodrigues; Oliver, Constance; Jamur, Maria Célia

    2015-01-01

    The fungus Paracoccidioides brasiliensis is the leading etiological agent of paracoccidioidomycosis (PCM), a systemic granulomatous disease that typically affects the lungs. Cell wall components of P. brasiliensis interact with host cells and influence the pathogenesis of PCM. In yeast, many glycosylphosphatidylinositol (GPI)-anchored proteins are important in the initial contact with the host, mediating host-yeast interactions that culminate with the disease. PbPga1 is a GPI anchored protein located on the surface of the yeast P. brasiliensis that is recognized by sera from PCM patients. Endogenous PbPga1 was localized to the surface of P. brasiliensis yeast cells in the lungs of infected mice using a polyclonal anti-rPbPga1 antibody. Furthermore, macrophages stained with anti-CD38 were associated with P. brasiliensis containing granulomas. Additionally, rPbPga1 activated the transcription factor NFkB in the macrophage cell line Raw 264.7 Luc cells, containing the luciferase gene downstream of the NFkB promoter. After 24 h of incubation with rPbPga1, alveolar macrophages from BALB/c mice were stimulated to release TNF-α, IL-4 and NO. Mast cells, identified by toluidine blue staining, were also associated with P. brasiliensis containing granulomas. Co-culture of P. Brasiliensis yeast cells with RBL-2H3 mast cells induced morphological changes on the surface of the mast cells. Furthermore, RBL-2H3 mast cells were degranulated by P. brasiliensis yeast cells, but not by rPbPga1, as determined by the release of beta-hexosaminidase. However, RBL-2H3 cells activated by rPbPga1 released the inflammatory interleukin IL-6 and also activated the transcription factor NFkB in GFP-reporter mast cells. The transcription factor NFAT was not activated when the mast cells were incubated with rPbPga1. The results indicate that PbPga1 may act as a modulator protein in PCM pathogenesis and serve as a useful target for additional studies on the pathogenesis of P. brasiliensis.

  7. rPbPga1 from Paracoccidioides brasiliensis Activates Mast Cells and Macrophages via NFkB

    PubMed Central

    Valim, Clarissa Xavier Resende; da Silva, Elaine Zayas Marcelino; Assis, Mariana Aprigio; Fernandes, Fabricio Freitas; Coelho, Paulo Sergio Rodrigues; Oliver, Constance; Jamur, Maria Célia

    2015-01-01

    Background The fungus Paracoccidioides brasiliensis is the leading etiological agent of paracoccidioidomycosis (PCM), a systemic granulomatous disease that typically affects the lungs. Cell wall components of P. brasiliensis interact with host cells and influence the pathogenesis of PCM. In yeast, many glycosylphosphatidylinositol (GPI)-anchored proteins are important in the initial contact with the host, mediating host-yeast interactions that culminate with the disease. PbPga1 is a GPI anchored protein located on the surface of the yeast P. brasiliensis that is recognized by sera from PCM patients. Methodology/Principal Findings Endogenous PbPga1 was localized to the surface of P. brasiliensis yeast cells in the lungs of infected mice using a polyclonal anti-rPbPga1 antibody. Furthermore, macrophages stained with anti-CD38 were associated with P. brasiliensis containing granulomas. Additionally, rPbPga1 activated the transcription factor NFkB in the macrophage cell line Raw 264.7 Luc cells, containing the luciferase gene downstream of the NFkB promoter. After 24 h of incubation with rPbPga1, alveolar macrophages from BALB/c mice were stimulated to release TNF-α, IL-4 and NO. Mast cells, identified by toluidine blue staining, were also associated with P. brasiliensis containing granulomas. Co-culture of P. Brasiliensis yeast cells with RBL-2H3 mast cells induced morphological changes on the surface of the mast cells. Furthermore, RBL-2H3 mast cells were degranulated by P. brasiliensis yeast cells, but not by rPbPga1, as determined by the release of beta-hexosaminidase. However, RBL-2H3 cells activated by rPbPga1 released the inflammatory interleukin IL-6 and also activated the transcription factor NFkB in GFP-reporter mast cells. The transcription factor NFAT was not activated when the mast cells were incubated with rPbPga1. Conclusions/Significance The results indicate that PbPga1 may act as a modulator protein in PCM pathogenesis and serve as a useful target for

  8. Epidemiological and biological aspects on Ornithodoros brasiliensis (mouro tick), an argasidae tick only found on the highlands region of Rio Grande do Sul state, southern Brazil

    USDA-ARS?s Scientific Manuscript database

    The soft tick Ornithodoros brasiliensis (Acari: Argasidae) is present in farms along the highlands of Rio Grande do Sul state in southern Brazil. Reports of human parasitism by O. brasiliensis drew the attention of local health authorities. A preliminary epidemiological survey was conducted to ident...

  9. The malate synthase of Paracoccidioides brasiliensis is a linked surface protein that behaves as an anchorless adhesin

    PubMed Central

    2009-01-01

    Background The pathogenic fungus Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis (PCM). This is a pulmonary mycosis acquired by inhalation of fungal airborne propagules that can disseminate to several organs and tissues leading to a severe form of the disease. Adhesion and invasion to host cells are essential steps involved in the internalization and dissemination of pathogens. Inside the host, P. brasiliensis may use the glyoxylate cycle for intracellular survival. Results Here, we provide evidence that the malate synthase of P. brasiliensis (PbMLS) is located on the fungal cell surface, and is secreted. PbMLS was overexpressed in Escherichia coli, and polyclonal antibody was obtained against this protein. By using Confocal Laser Scanning Microscopy, PbMLS was detected in the cytoplasm and in the cell wall of the mother, but mainly of budding cells of the P. brasiliensis yeast phase. PbMLSr and its respective polyclonal antibody produced against this protein inhibited the interaction of P. brasiliensis with in vitro cultured epithelial cells A549. Conclusion These observations indicated that cell wall-associated PbMLS could be mediating the binding of fungal cells to the host, thus contributing to the adhesion of fungus to host tissues and to the dissemination of infection, behaving as an anchorless adhesin. PMID:20034376

  10. Toxicological profile of deltamethrin in Triatoma brasiliensis (Hemiptera: Reduviidae) in State of Ceará, Northeastern Brazil.

    PubMed

    Pessoa, Grasielle Caldas D'Ávila; Trevizani, Nathália Abreu Borges; Dias, Letícia Sena; Bezerra, Claudia Mendonça de; Melo, Bernardino Vaz de; Diotaiut, Liléia

    2015-01-01

    Triatoma brasiliensis is the species of greatest epidemiological relevance in the semi-arid region of Brazil. This species is predominantly found in domestic environments, and it has the ability to build large colonies with high levels of natural infection via Trypanosoma cruzi. Thus, T. brasiliensis is one of the most efficient transmitters of Chagas disease (CD) to humans. Despite household spraying with residual insecticides, many areas report persistent reinfestations for reasons that remain poorly understood. Therefore, this study sought to characterize the toxicological profile of deltamethrin in T. brasiliensis from areas with persistent reinfestation in State of Ceará, Brazil. The susceptibility reference lineage (SRL) was derived from Umari. Serial dilutions of deltamethrin were prepared and applied to the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed mortality in response to a diagnostic dose of 1xLD99 (0.851 nanograms of active ingredient per treated nymph) of the SRL. The susceptibility profile characterization of the T. brasiliensis populations revealed 50% resistance ratios (RR50) that ranged from 0.32 to 1.21. The percentage of mortality in response to the diagnostic dose was 100%. We demonstrated that T. brasiliensis was highly susceptible to deltamethrin. The control difficulties found might be related to the recolonization of the triatomines originating from neighboring environments and the possible operational failures related to the process of spraying that enabled specimens less susceptible to deltamethrin to survive.

  11. IgM and IgG antibody response to Paracoccidioides brasiliensis in naturally infected wild armadillos (Dasypus novemcinctus).

    PubMed

    Fernandes, G F; Deps, P; Tomimori-Yamashita, J; Camargo, Z P

    2004-08-01

    We studied the extent to which wild nine-banded armadillos, Dasypus novemcinctus, produce immune humoral responses specifically directed against characteristic Paracoccidioides brasiliensis antigens. Such antibody production might reflect direct contact with the ecological microniche of P. brasiliensis, or might merely reflect inhalation of widely distributed airborne propagules. An enzyme-linked immunosorbent assay (ELISA) was designed containing purified glycoprotein gp43 and gp70 antigens from P. brasiliensis as well as cross-reactive antisera originally targeted against human IgM (mu chain) and armadillo anti-IgG (gamma-chain). It was used to detect and classify IgM and IgG antibodies to P. brasiliensis in the armadillo. In a serological survey of 47 wild armadillos, IgM antibodies to gp43 were detected in seven animals (14.8%), and IgG antibodies were detected in 20 (42.5%). IgM antibodies to gp70 were detected in 10 (21.3%) animals and IgG antibodies were detected in 18 (38.3%). These results, showing a pattern consistent with infection, suggest that P. brasiliensis is enzootic in armadillos. How the animals became exposed could not be determined.

  12. Amphotericin B, alone or followed by itraconazole therapy, is effective in the control of experimental disseminated sporotrichosis by Sporothrix brasiliensis.

    PubMed

    Ishida, Kelly; de Castro, Rafaela Alves; Borba Dos Santos, Luana Pereira; Quintella, Leonardo Pereira; Lopes-Bezerra, Leila M; Rozental, Sonia

    2015-01-01

    Sporothrix brasiliensis is a highly virulent member of the S. schenckii complex, which is responsible for the emergence of the epidemic sporotrichosis in southeastern Brazil over the last two decades. There are no in vivo studies on the sensitivity of S. brasiliensis to the therapeutic regimens used to treat sporotrichosis. Here, we evaluated the efficacy and safety of antifungal treatments against S. brasiliensis using a murine model of disseminated sporotrichosis. In vitro, S. brasiliensis yeasts were sensitive to low concentrations of amphotericin B-deoxycholate (AMB-d) and itraconazole (ITZ), the latter having greater selectivity toward the fungus. The following treatment regimens were tested in vivo: intravenous AMB-d for 7 days post-infection (p.i.), oral ITZ for up to 30 days p.i., and AMB-d followed by ITZ (AMB-d/ITZ). AMB-d and AMB-d/ITZ led to 100% survival of infected mice at the end of the 45-day experimental period. Although all treatments extended mice survival, only AMB-d and AMB-d/ITZ significantly reduced fungal load in all organs, but AMB-d/ITZ led to a more consistent decrease in overall fungal burden. No treatment increased the levels of serum toxicity biomarkers. Taken together, our results indicate that AMB-d/ITZ is the best therapeutic option for controlling disseminated sporotrichosis caused by S. brasiliensis.

  13. The Cloning of America.

    ERIC Educational Resources Information Center

    Dobson, Judith E.; Dobson, Russell L.

    1981-01-01

    Proposes that the U.S. school system purports to prize human variability, but many educators are engaged in activities that seek to homogenize students. Describes these activities, including diagnosis, labeling, ability grouping, and positive reinforcement. Presents suggestions for counselors to combat sources of cloning and self-validation. (RC)

  14. Secure the Clones

    NASA Astrophysics Data System (ADS)

    Jensen, Thomas; Kirchner, Florent; Pichardie, David

    Exchanging mutable data objects with untrusted code is a delicate matter because of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java stress the importance of using defensive copying before accepting or handing out references to an internal mutable object. However, implementation of a copy method (like clone()) is entirely left to the programmer. It may not provide a sufficiently deep copy of an object and is subject to overriding by a malicious sub-class. Currently no language-based mechanism supports secure object cloning. This paper proposes a type-based annotation system for defining modular copy policies for class-based object-oriented programs. A copy policy specifies the maximally allowed sharing between an object and its clone. We present a static enforcement mechanism that will guarantee that all classes fulfill their copy policy, even in the presence of overriding of copy methods, and establish the semantic correctness of the overall approach in Coq. The mechanism has been implemented and experimentally evaluated on clone methods from several Java libraries.

  15. Applications of quantum cloning

    NASA Astrophysics Data System (ADS)

    Pomarico, E.; Sanguinetti, B.; Sekatski, P.; Zbinden, H.; Gisin, N.

    2011-10-01

    Quantum Cloning Machines (QCMs) allow for the copying of information, within the limits imposed by quantum mechanics. These devices are particularly interesting in the high-gain regime, i.e., when one input qubit generates a state of many output qubits. In this regime, they allow for the study of certain aspects of the quantum to classical transition. The understanding of these aspects is the root of the two recent applications that we will review in this paper: the first one is the Quantum Cloning Radiometer, a device which is able to produce an absolute measure of spectral radiance. This device exploits the fact that in the quantum regime information can be copied with only finite fidelity, whereas when a state becomes macroscopic, this fidelity gradually increases to 1. Measuring the fidelity of the cloning operation then allows to precisely determine the absolute spectral radiance of the input optical source. We will then discuss whether a Quantum Cloning Machine could be used to produce a state visible by the naked human eye, and the possibility of a Bell Experiment with humans playing the role of detectors.

  16. The Cloning of America.

    ERIC Educational Resources Information Center

    Dobson, Judith E.; Dobson, Russell L.

    1981-01-01

    Proposes that the U.S. school system purports to prize human variability, but many educators are engaged in activities that seek to homogenize students. Describes these activities, including diagnosis, labeling, ability grouping, and positive reinforcement. Presents suggestions for counselors to combat sources of cloning and self-validation. (RC)

  17. Pulmonary infection in two sympatric lizards, Mabuya arajara (Scincidae) and Anolis brasiliensis (Polychrotidae) from a cloud forest in Chapada do Araripe, Ceará, Northeastern Brazil.

    PubMed

    Ribeiro, S C; Ferreira, F S; Brito, S V; Teles, D A; Ávila, R W; Almeida, W O; Anjos, L A; Guarnieri, M C

    2012-11-01

    The parameters of infection by lung parasites from two sympatric lizards, Mabuya arajara and Anolis brasiliensis, from the Atlantic Rainforest of the lower slope of Chapada do Araripe in Northeastern Brazil were analyzed between September, 2009 and July, 2010. A total of 202 lizards were collected. 125 specimens were from Mabuya arajara and 77 from Anolis brasiliensis. M. arajara was infected by the pentastomid Raillietiella mottae while A. brasiliensis was infected by the nematode Rhabdias sp., with an overall prevalence of 1.6% and 28.6%, respectively. The mean intensity of infection by Rhabdias sp. was 3.63 ± 2.58 (range 1-15). The body size and sex of lizards did not influence the intensity of infection by Rhabdias sp. The overall prevalence was also not different between males and females hosts in A. brasiliensis. Both Anolis brasiliensis and Mabuya arajara represent a new host to Rhabdias sp. and Raillietiella mottae, respectively.

  18. Lactic dehydrogenase virus infection enhances parasite egg production and inhibits eosinophil and mast cell responses in mice infected with the nematode Nippostrongylus brasiliensis.

    PubMed Central

    Morimoto, M; Yamada, M; Arizono, N; Hayashi, T

    1998-01-01

    The effects of lactic dehydrogenase virus (LDV) infection on the protective immune responses to the nematode Nippostrongylus brasiliensis were studied. Mice with chronic LDV infection showed significantly higher levels of parasite egg production than non-LDV-infected (control) mice after N. brasiliensis infection. Concurrent LDV infection also suppressed peripheral blood eosinophilia and the lung mastocytosis induced by this nematode. LDV infection showed higher expression levels of the interferon-gamma (IFN-gamma) mRNA in lymph nodes compared with control mice before N. brasiliensis infection. In addition, the IgG2a production in LDV-infected mice was higher than that in control mice before and after N. brasiliensis infection. These results suggest that LDV infection modulates protective immune responses against N. brasiliensis infection by the activation of T-helper type 1 cells. PMID:9659227

  19. Sequential cloning of chromosomes

    SciTech Connect

    Lacks, S.A.

    1991-12-31

    A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  20. The First Human Cloned Embryo.

    ERIC Educational Resources Information Center

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  1. The First Human Cloned Embryo.

    ERIC Educational Resources Information Center

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  2. [Nuclear transfer and therapeutic cloning].

    PubMed

    Xu, Xiao-Ming; Lei, An-Min; Hua, Jin-Lian; Dou, Zhong-Ying

    2005-03-01

    Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.

  3. Cloning Components of Human Telomerase.

    DTIC Science & Technology

    1998-07-01

    nuclear factor NF90 homolog. (5 clones). RNA binding protein. Poorly understood. 3. FRG1 . Poorly understood. 4. DEK. Weak homology to Tetrahymena p95...least some of the clones for poorly understood genes (e.g. Hax-1, FRG1 , NF90, NF45, KIAA0098, KIAA0026, BAC397c4). Aim II. Functional Cloning of the

  4. Water relations of populus clones

    SciTech Connect

    Pallardy, S.G.; Kozlowski, T.T.

    1981-02-01

    Stomatal aperture and water balance in the field of eight Populus clones varying in growth rate were closely related to environmental factors and clonal differences were clearly expressed. Leaf water potential (psi) was influenced by solar radiation, leaf conductance, evaporative demand, and soil moisture content. The effects of soil moisture on psi were greatly modified by atmospheric conditions and stomatal conductance. Several slow-growing clones exhibited extended periods of psi below that of rapidly growing clones, despite high evaporative demand and the much greater transpiring surfaces of the fast-growing clones. Stomata of all clones responded to changes in light intensity and vapor pressure gradient (VPG). Pronounced stomatal sensitivity to VPG of two rapidly growing clones of common parentage, and the resultant capacity of these clones to moderate water deficits under high evaporative demand, were associated with drought resistance in one of the parents. Seasonal maximum leaf conductance was positively related to growth in several clones, suggesting that rapidly growing clones possess the capacity to carry on higher rates of gas exchange under favorable conditions. Analysis of changes in psi with changes in transpirational flux density (TFD) showed that for four clones, psi change per unit change in TFD decreased as TFD increased, indicating plant adaptation for prevention of damaging psi even at high TFD. More rapidly growing clones exhibited a larger initial rate of decline in psi with TFD, but reduced the rate of decline more than slow-growing clones as TFD increased. (Refs. 41).

  5. Neurological and multiple organ involvement due to Paracoccidioides brasiliensis and HIV co-infection diagnosed at autopsy.

    PubMed

    de Almeida, Sergio Monteiro; Roza, Thiago H; Salvador, Gabriel L O; França, João C B; Vidal, Luine Rosele Renaud; Nogueira, Meri Bordignon; Oliva, Lubomira Veronica; Torres, Luis Fernando Bleggi; de Noronha, Lucia Helena

    2017-09-11

    Paracoccidioidomycosis (PCM), caused by Paracoccidioides brasiliensis, is the most prevalent systemic mycosis among immunocompetent patients in Latin America; it is rare in immunocompromised patients. The estimated frequency of central nervous system (CNS) involvement in the HIV/PCM population was 2.5%. We report a case of HIV/P. brasiliensis co-infection, with neurological (NPCM) and multiple organ involvement, indicating a diagnosis of AIDS. PCM diagnosis was established during the autopsy. This is the first described case of HIV/P. brasiliensis co-infection with CNS involvement diagnosed at autopsy. In conclusion, the diagnosis of NPCM is challenging, and it must be considered in the differential diagnosis in HIV-positive patients who reside in or have visited areas in which the condition is endemic and who present with neurological symptoms.

  6. Effects of polysaccharide from fruiting bodies of Agaricus bisporus, Agaricus brasiliensis, and Phellinus linteus on alcoholic liver injury.

    PubMed

    Uyanoglu, Mustafa; Canbek, Mediha; van Griensven, Leo J L D; Yamac, Mustafa; Senturk, Hakan; Kartkaya, Kazım; Oglakcı, Aysegul; Turgak, Ozge; Kanbak, Gungor

    2014-06-01

    In the present study, the curative effects of crude polysaccharides (PSs) from mushrooms on the symptoms of alcoholic liver injury were investigated. PSs from Agaricus bisporus, Agaricus brasiliensis, and Phellinus linteus fruiting bodies were administered by gavage at levels of 100 mg per kg body weight per day for 7 d after the onset of the disease. The caspase-3 activity, mitochondrial membrane potential, mitochondrial outer membrane integrity of the liver tissues of sacrificed rats, and the serum alanine aminotransferase (ALT) levels were determined. In addition, light and transmission electron microscope (TEM) studies were performed for histopathological and cytological evaluations on liver sections. PSs from A. brasiliensis decreased ALT level and mitochondrial membrane potential and increased the outer membrane integrity; microscopic examinations also revealed normal hepatocytes and tissue. On the basis of our data, it can be argued that crude PSs from Agaricus brasiliensis have therapeutic potential for alcoholic liver injury.

  7. Antibodies Against Glycolipids Enhance Antifungal Activity of Macrophages and Reduce Fungal Burden After Infection with Paracoccidioides brasiliensis.

    PubMed

    Bueno, Renata A; Thomaz, Luciana; Muñoz, Julian E; da Silva, Cássia J; Nosanchuk, Joshua D; Pinto, Márcia R; Travassos, Luiz R; Taborda, Carlos P

    2016-01-01

    Paracoccidioidomycosis is a fungal disease endemic in Latin America. Polyclonal antibodies to acidic glycosphingolipids (GSLs) from Paracoccidioides brasiliensis opsonized yeast forms in vitro increasing phagocytosis and reduced the fungal burden of infected animals. Antibodies to GSL were active in both prophylactic and therapeutic protocols using a murine intratracheal infection model. Pathological examination of the lungs of animals treated with antibodies to GSL showed well-organized granulomas and minimally damaged parenchyma compared to the untreated control. Murine peritoneal macrophages activated by IFN-γ and incubated with antibodies against acidic GSLs more effectively phagocytosed and killed P. brasiliensis yeast cells as well as produced more nitric oxide compared to controls. The present work discloses a novel target of protective antibodies against P. brasiliensis adding to other well-studied mediators of the immune response to this fungus.

  8. Recombinational Cloning Using Gateway and In-Fusion Cloning Schemes

    PubMed Central

    Throop, Andrea L.; LaBaer, Joshua

    2015-01-01

    The comprehensive study of protein structure and function, or proteomics, depends on the obtainability of full-length cDNAs in species-specific expression vectors and subsequent functional analysis of the expressed protein. Recombinational cloning is a universal cloning technique based on site-specific recombination that is independent of the insert DNA sequence of interest, which differentiates this method from the classical restriction enzyme-based cloning methods. Recombinational cloning enables rapid and efficient parallel transfer of DNA inserts into multiple expression systems. This unit summarizes strategies for generating expression-ready clones using the most popular recombinational cloning technologies, including the commercially available Gateway® (Life Technologies) and In-Fusion® (Clontech) cloning technologies. PMID:25827088

  9. Three concepts of cloning in human beings.

    PubMed

    Cui, Ke-Hui

    2005-07-01

    Human cloning, organ cloning and tissue cloning are various types of cloning that occur at different levels with different methodologies. According to three standards of terminology for an embryo (fertilization through germ cells, development in the uterus and having the potential to produce a human life), tissue cloning and type I organ cloning will not produce an embryo. In contrast, human cloning and type II organ cloning will produce an embryo. Thus, only non-germinal tissue cloning and type I organ cloning are beyond the ethical question and will not change human beings as a species. Using cloned tissues to make new tissues or organs is promising for the future of medicine.

  10. Detection of Antibodies against Paracoccidioides brasiliensis Melanin in In Vitro and In Vivo Studies during Infection ▿

    PubMed Central

    Urán, Martha E.; Nosanchuk, Joshua D.; Restrepo, Angela; Hamilton, Andrew J.; Gómez, Beatriz L.; Cano, Luz E.

    2011-01-01

    Several cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogen Paracoccidioides brasiliensis produces melanin in its conidial and yeast forms. In the present study, melanin particles from P. brasiliensis were injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) κ-chain and four IgM melanin-binding MAbs. The five IgG1 κ-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeled P. brasiliensis conidia and yeast cells both in vitro and in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic and Sepia officinalis melanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin from P. brasiliensis conidia and yeast in sera and bronchoalveolar lavage fluids from P. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin from P. brasiliensis is an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice. PMID:21813659

  11. Redox-active biflavonoids from Garcinia brasiliensis as inhibitors of neutrophil oxidative burst and human erythrocyte membrane damage.

    PubMed

    Saroni Arwa, Phanuel; Zeraik, Maria Luiza; Ximenes, Valdecir Farias; da Fonseca, Luiz Marcos; Bolzani, Vanderlan da Silva; Siqueira Silva, Dulce Helena

    2015-11-04

    Garcinia brasiliensis, a plant native to the Brazilian Amazon Rainforest, is used in traditional medicine to treat inflammation of the urinary tract, peptic ulcers, arthritis and other conditions. The purposes of this study were to analyze the chemical constituents of G. brasiliensis branches and leaves and to evaluate the potential of isolated compounds to act as inhibitors of both the oxidative burst of stimulated neutrophils and oxidative damage in human erythrocyte membranes to verify the antioxidant and anti-inflammatory effects of this plant. Neutrophils were isolated from the blood of healthy donors by Ficoll-Paque density gradient centrifugation. Superoxide anion and total reactive oxygen species (ROS) produced by stimulated neutrophils were measured by WST-1 reduction and luminol-enhanced chemiluminescence assays, respectively. Radical-induced lipoperoxidation and hemolysis were performed using erythrocytes from the blood of healthy donors. Compounds were isolated from G. brasiliensis branches and leaves by HPLC microfractionation, and structure elucidation of the isolated compounds was performed based on NMR and HR-MS analyses. The biflavonoids procyanidin, fukugetin, amentoflavone and podocarpusflavone isolated from G. brasiliensis showed potent inhibitory effects on the oxidative burst of human neutrophils, inhibiting ROS production by 50% at 1 μmol L(-1). These biflavonoids also proved to be potent inhibitors of hemolysis (with 88 ± 7% inhibition at 50 µmol L(-1) for procyanidin) and lipid peroxidation in human erythrocytes, with a malondialdehyde level (a biomarker of oxidative stress) of 8.5 ± 0.3 nmol/mg Hb at 50 µmol L(-1) for procyanidin. These findings indicate that the biflavonoids extracted from G. brasiliensis branches and leaves modulate oxidative stress via inhibition of NADPH oxidase and ROS production by stimulated human neutrophils. Furthermore, the biflavonoids exhibited potent inhibition of oxidant hemolysis and lipid peroxidation

  12. Differences in Cell Morphometry, Cell Wall Topography and Gp70 Expression Correlate with the Virulence of Sporothrix brasiliensis Clinical Isolates

    PubMed Central

    Castro, Rafaela A.; Kubitschek-Barreira, Paula H.; Teixeira, Pedro A. C.; Sanches, Glenda F.; Teixeira, Marcus M.; Quintella, Leonardo P.; Almeida, Sandro R.; Costa, Rosane O.; Camargo, Zoilo P.; Felipe, Maria S. S.; de Souza, Wanderley; Lopes-Bezerra, Leila M.

    2013-01-01

    Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes. PMID:24116065

  13. The Homeostasis of Iron, Copper, and Zinc in Paracoccidioides Brasiliensis, Cryptococcus Neoformans Var. Grubii, and Cryptococcus Gattii: A Comparative Analysis

    PubMed Central

    Silva, Mirelle Garcia; Schrank, Augusto; Bailão, Elisa Flávia L.C.; Bailão, Alexandre Melo; Borges, Clayton Luiz; Staats, Charley Christian; Parente, Juliana Alves; Pereira, Maristela; Salem-Izacc, Silvia Maria; Mendes-Giannini, Maria José Soares; Oliveira, Rosely Maria Zancopé; Silva, Lívia Kmetzsch Rosa e; Nosanchuk, Joshua D.; Vainstein, Marilene Henning; de Almeida Soares, Célia Maria

    2011-01-01

    Iron, copper, and zinc are essential for all living organisms. Moreover, the homeostasis of these metals is vital to microorganisms during pathogenic interactions with a host. Most pathogens have developed specific mechanisms for the uptake of micronutrients from their hosts in order to counteract the low availability of essential ions in infected tissues. We report here an analysis of genes potentially involved in iron, copper, and zinc uptake and homeostasis in the fungal pathogens Paracoccidioides brasiliensis, Cryptococcus neoformans var. grubii, and Cryptococcus gattii. Although prior studies have identified certain aspects of metal regulation in Cryptococcus species, little is known regarding the regulation of these elements in P. brasiliensis. We also present amino acid sequences analyses of deduced proteins in order to examine possible conserved domains. The genomic data reveals, for the first time, genes associated to iron, copper, and zinc assimilation and homeostasis in P. brasiliensis. Furthermore, analyses of the three fungal species identified homologs to genes associated with high-affinity uptake systems, vacuolar and mitochondrial iron storage, copper uptake and reduction, and zinc assimilation. However, homologs to genes involved in siderophore production were only found in P. brasiliensis. Interestingly, in silico analysis of the genomes of P. brasiliensis Pb01, Pb03, and Pb18 revealed significant differences in the presence and/or number of genes involved in metal homeostasis, such as in genes related to iron reduction and oxidation. The broad analyses of the genomes of P. brasiliensis, C. neoformans var. grubii, and C. gattii for genes involved in metal homeostasis provide important groundwork for numerous interesting future areas of investigation that are required in order to validate and explore the function of the identified genes and gene pathways. PMID:21833306

  14. Mammalian cloning: advances and limitations.

    PubMed

    Solter, D

    2000-12-01

    For many years, researchers cloning mammals experienced little success, but recent advances have led to the successful cloning of several mammalian species. However, cloning by the transfer of nuclei from adult cells is still a hit-and-miss procedure, and it is not clear what technical and biological factors underlie this. Our understanding of the molecular basis of reprogramming remains extremely limited and affects experimental approaches towards increasing the success rate of cloning. Given the future practical benefits that cloning can offer, the time has come to address what should be done to resolve this problem.

  15. Diet and helminths of Enyalius brasiliensis (Lacertilia, Iguania, Leiosauridae) in an Atlantic Rainforest remnant in southeastern Brazil.

    PubMed

    Dorigo, T A; Maia-Carneiro, T; Almeida-Gomes, M; Siqueira, C C; Vrcibradic, D; Van Sluys, M; Rocha, C F D

    2014-02-01

    Our study aimed to add information about the diet and endoparasites of Enyalius brasiliensis from an Atlantic Rainforest remnant in the state of Rio de Janeiro, southeastern Brazil. Regarding diet, E. brasiliensis consumed arthropods, with caterpillars and beetles being the most important preys. Regarding helminth parasites, overall prevalence was low (9.5%), with 238 nematodes of the genus Physaloptera found in the stomach of one specimen and one nematode of the genus Rhabdias inside the lung of another. Our results corroborate the observations of previous studies that indicate that lizards of the genus Enyalius tend to feed mainly on relatively large-bodied arthropods and to harbour depauperate endoparasite fauna.

  16. cDNA encoding a polypeptide including a hevein sequence

    DOEpatents

    Raikhel, Natasha V.; Broekaert, Willem F.; Chua, Nam-Hai; Kush, Anil

    1993-02-16

    A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a pu GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon.

  17. Sequential cloning of chromosomes

    DOEpatents

    Lacks, Sanford A.

    1995-07-18

    A method for sequential cloning of chromosomal DNA of a target organism is disclosed. A first DNA segment homologous to the chromosomal DNA to be sequentially cloned is isolated. The first segment has a first restriction enzyme site on either side. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism's chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction (class IIS) enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  18. Sequential cloning of chromosomes

    DOEpatents

    Lacks, S.A.

    1995-07-18

    A method for sequential cloning of chromosomal DNA of a target organism is disclosed. A first DNA segment homologous to the chromosomal DNA to be sequentially cloned is isolated. The first segment has a first restriction enzyme site on either side. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction (class IIS) enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes. 9 figs.

  19. Ethical issues in livestock cloning.

    PubMed

    Thompson, P B

    1999-01-01

    Although cloning may eventually become an important technology for livestock production, four ethical issues must be addressed before the practice becomes widespread. First, researchers must establish that the procedure is not detrimental to the health or well-being of affected animals. Second, animal research institutions should evaluate the net social benefits to livestock producers by weighing the benefits to producers against the opportunity cost of research capacity lost to biomedical projects. Third, scientists should consider the indirect effects of cloning research on the larger ethical issues surrounding human cloning. Finally, the market structure for products of cloned animals should protect individual choice, and should recognize that many individuals find the prospect of cloning (or consuming cloned animals) repugnant. Analysis of these four issues is complicated by spurious arguments alleging that cloning will have a negative impact on environment and genetic diversity.

  20. Probabilistic cloning of equidistant states

    SciTech Connect

    Jimenez, O.; Roa, Luis; Delgado, A.

    2010-08-15

    We study the probabilistic cloning of equidistant states. These states are such that the inner product between them is a complex constant or its conjugate. Thereby, it is possible to study their cloning in a simple way. In particular, we are interested in the behavior of the cloning probability as a function of the phase of the overlap among the involved states. We show that for certain families of equidistant states Duan and Guo's cloning machine leads to cloning probabilities lower than the optimal unambiguous discrimination probability of equidistant states. We propose an alternative cloning machine whose cloning probability is higher than or equal to the optimal unambiguous discrimination probability for any family of equidistant states. Both machines achieve the same probability for equidistant states whose inner product is a positive real number.

  1. Characterization of gp70 and Anti-gp70 Monoclonal Antibodies in Paracoccidioides brasiliensis Pathogenesis

    PubMed Central

    de Mattos Grosso, Daniela; de Almeida, Sandro Rogério; Mariano, Mario; Lopes, Jose Daniel

    2003-01-01

    Paracoccidioidomycosis (PCM) is a systemic granulomatous mycosis whose agent is Paracoccidioides brasiliensis. In the culture supernatant, the fungus expresses glycoproteins of from 13 to 148 kDa. A cell surface glycoprotein of 43 kDa is the major antigenic component of P. brasiliensis. Another expressed glycoprotein, gp70, is recognized by 96% of sera from PCM patients and is able to induce lymphoproliferation. Since, little is known about this glycoprotein, we produced monoclonal antibodies (MAbs) against gp70 to isolate the molecule from total fungus extracts and to investigate its possible role in the pathogenesis of PCM. Using these MAbs, it was observed by confocal microscopy that gp70 is located mainly in the intracellular compartment of the fungus, although it was also detected in the culture supernatant. Based on observations showing that gp43 has a down-regulatory effect on mouse peritoneal macrophages, we tested the effects of gp70 on their phagocytic ability. Purified gp70 was able to inhibit the activity of macrophages through the mannose receptors and also through the Fc receptors; the latter effect was not observed with gp43. gp70 inhibits NO and H2O2 liberation by peritoneal macrophages in vitro, as does gp43. Results obtained with gp43 led us to hypothesize that gp70 could act as an escape mechanism for fungal establishment in primary infections. To corroborate this hypothesis, we analyzed the effect of passive immunization of mice during infection with P. brasiliensis using anti-gp70 MAbs. This treatment almost completely abolished granuloma formation in the lungs, suggesting that the protein facilitates fungal establishment and progression of lesions in primary infection. PMID:14573675

  2. Bioconcentration and bioaccumulation of metal in freshwater Neotropical fish Geophagus brasiliensis.

    PubMed

    Voigt, Carmen Lúcia; da Silva, Cleber Pinto; Doria, Halina Binde; Randi, Marco Antônio Ferreira; de Oliveira Ribeiro, Ciro Alberto; de Campos, Sandro Xavier

    2015-06-01

    From the concentration in water and sediments, bioconcentration and bioaccumulation of copper (Cu), manganese (Mn), zinc (Zn), iron (Fe), cobalt (Co), cadmium (Cd), chrome (Cr), silver (Ag), lead (Pb), nickel (Ni), aluminum (Al), and arsenic (As) were determined in the gills, liver, and muscles of Geophagus brasiliensis in the Alagados Reservoir, Ponta Grossa, Paraná, Brazil. Metals were quantified through AAS, and a study was carried out on the existing relations between metal and body weight, size, and genre of this species. The level of metal in the water of the reservoir was lower than the maximum set forth in the legislation, except for that of Cd and Fe. In sediments, Cu, Cd, Cr, and Ni presented concentrations above the threshold effect level (TEL). Pb and Cr were above the limits for the G. brasiliensis. The tendency of metals present in the muscles of G. brasiliensis was Al > Cu > Zn > Fe > Co > Mn > Cr > Ag > Ni > Pb > Cd > As. In the gills, it was Al > Fe > Zn > Mn > Co > Ag > Cr > Ni > Cu > As > Pb > Cd, and the liver presented Al > Cu > Zn > Co > Fe > Mn > Pb > Ag > Ni > Cr > As > Cd. The bioconcentration and bioaccumulation of metal in the tissues follow the global tendency liver > gills > muscle. The statistical analysis did not point to significant differences in the metal concentration and body weight, size, and gender of the species in the three tissues under analysis.

  3. Refractory sporotrichosis due to Sporothrix brasiliensis in humans appears to be unrelated to in vivo resistance.

    PubMed

    Almeida-Paes, Rodrigo; Oliveira, Manoel Marques Evangelista; Freitas, Dayvison Francis Saraiva; Valle, Antônio Carlos Francesconi do; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely Maria

    2017-07-01

    Sporotrichosis is a subacute to chronic infection caused by members of the Sporothrix schenckii complex. Itraconazole is the first choice antifungal drug for treating this infection, with terbinafine and potassium iodide as alternatives and amphotericin B used in cases of severe infections. Correlation of antifungal susceptibility data with the clinical outcome of the patients is scarce. The aim of this study was to correlate clinical and mycological data in patients with refractory sporotrichosis. In this work, antifungal susceptibilities, determined according to the reference M38-A2 CLSI protocol, of 25 Sporothrix strains, isolated from seven human cases of sporotrichosis with adversities in the treatment, are presented. Tested drugs included itraconazole, ketoconazole, posaconazole, voriconazole, terbinafine, and amphotericin B. Fungi were identified using the T3B PCR fingerprinting. This method identified all strains as Sporothrix brasiliensis and also demonstrated a high degree of similarity between the strains. In general, voriconazole was ineffective against all strains, and elevated minimal inhibitory concentrations (MICs) were observed for amphotericin B. High itraconazole and terbinafine MICs were not observed in S. brasiliensis isolates from patients of this study. Moreover, a significant increase in itraconazole and terbinafine MIC values from strains isolated from the same patient in different periods was not observed. The results suggest that the antifungal susceptibility to terbinafine and itraconazole determined by the reference method does not play an important role in therapeutic failure of sporotrichosis and that acquisition of resistance during prolonged antifungal treatment is not likely to occur in S. brasiliensis. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. A cross-reactive monoclonal antibody to nematode haemoglobin enhances protective immune responses to Nippostrongylus brasiliensis.

    PubMed

    Nieuwenhuizen, Natalie E; Meter, Jeanne M; Horsnell, William G; Hoving, J Claire; Fick, Lizette; Sharp, Michael F; Darby, Matthew G; Parihar, Suraj P; Brombacher, Frank; Lopata, Andreas L

    2013-01-01

    Nematode secreted haemoglobins have unusually high affinity for oxygen and possess nitric oxide deoxygenase, and catalase activity thought to be important in protection against host immune responses to infection. In this study, we generated a monoclonal antibody (48Eg) against haemoglobin of the nematode Anisakis pegreffii, and aimed to characterize cross-reactivity of 4E8g against haemoglobins of different nematodes and its potential to mediate protective immunity against a murine hookworm infection. Immunoprecipitation was used to isolat