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Sample records for seringueira hevea brasiliensis

  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. PMID:25399518

  2. Microsatellite marker development for the rubber tree (Hevea brasiliensis): characterization and cross-amplification in wild Hevea species

    PubMed Central

    2012-01-01

    Background The rubber tree (Hevea brasiliensis) is native to the Amazon region and it is the major source of natural rubber in the world. Rubber tree breeding is time-consuming and expensive. However, molecular markers such as microsatellites can reduce the time required for these programs. This study reports new genomic microsatellite markers developed and characterized in H. brasiliensis and the evaluation of their transferability to other Hevea species. Findings We constructed di- and trinucleotide-enriched libraries. From these two libraries, 153 primer pairs were designed and initially evaluated using 9 genotypes of H. brasiliensis. A total of 119 primer pairs had a good amplification product, 90 of which were polymorphic. We chose 46 of the polymorphic markers and characterized them in 36 genotypes of H. brasiliensis. The expected and observed heterozygosities ranged from 0.1387 to 0.8629 and 0.0909 to 0.9167, respectively. The polymorphism information content (PIC) values ranged from 0.097 to 0.8339, and the mean number of alleles was 6.4 (2–17). These 46 microsatellites were also tested in 6 other Hevea species. The percentage of transferability ranged from 82% to 87%. Locus duplication was found in H. brasiliensis and also in 5 of other species in which transferability was tested. Conclusions This study reports new microsatellite markers for H. brasiliensis that can be used for genetic linkage mapping, quantitative trait loci identification and marker- assisted selection. The high percentage of transferability may be useful in the evaluations of genetic variability and to monitor introgression of genetic variability from different Hevea species into breeding programs. PMID:22731927

  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. PMID:27317253

  4. Hydrophobic allergens from the bottom fraction membrane of Hevea brasiliensis.

    PubMed

    Mengumpun, Kesajee; Tayapiwatana, Chatchai; Hamilton, Robert G; Sangsupawanich, Pasuree; Wititsuwannakul, Rapepun

    2008-01-01

    Several proteins of rubber latex have been recognized as allergens causing immediate hypersensitivity in humans. In this study, a bottom fraction membrane (BFM) protein preparation from Hevea brasiliensis trees grown in southern Thailand was used to detect specific IgE in four groups of serum samples. The first group included 170 samples of latex glove factory workers (LGWs); group 2 consisted of the sera of 35 health care workers (HCWs) who were repeatedly exposed to powdered latex gloves; groups 3 and 4 were 31 positive and 22 negative sera, respectively, obtained from Johns Hopkins University School of Medicine, Baltimore, USA, tested for IgE to latex allergen. It was found that 56/170 (33%), 5/35 (14%), 11/31 (35.5%) and 1/22 (4.5%) samples of the LGWs, HCWs, CAP+ and CAP- groups had significant IgE to the BFM proteins, respectively. However, of all subjects only one subject of group 1 had experienced allergic morbidity consisting of eczema, conjunctivitis and asthma. The IgE of this subject bound to a 55 kDa component in the rubber latex BFM preparation. Thus, this protein may be regarded as a novel, although minor, latex allergen. Further investigation is needed to characterize the component and to pinpoint its allergenic role. PMID:19054931

  5. Biological control of Rigidoporus lignosus in Hevea brasiliensis in Nigeria.

    PubMed

    Ogbebor, Nicholas Obehi; Adekunle, Adefunke Temitayo; Eghafona, Odeh Nosakhare; Ogboghodo, Abraham Ikponmwosa

    2015-01-01

    The study was conducted to evaluate in vitro and in vivo control of fungal antagonists on Rigidoporus lignosus (klotzsch) Imaz in Hevea brasiliensis (Willd. ex A. Juss.) Muell. Arg. in the rain forest zone of Nigeria. In vitro assessments of biological agents were carried out in dixenic cultures in Petri plates. In vivo tests were carried out in the nursery using Hypocrea virens and Hypocrea jecorina. Significant differences were observed with the dual inoculations of fungal antagonists and R. lignosus inoculated the same day, and the antagonists inoculated 24 h before inoculation of R. lignosus. Hypocrea jecorina was most effective in the control of R. lignosus with percentage inhibition of 86.83 %. Hypocrea virens, H. jecorina, Trichoderma spirale, Trichoderma sp., Trichoderma sp. Pers, and Hypocrea lixii were effective on R. lignosus. Fungal antagonists inoculated 24 h before inoculation of R. lignosus exhibited higher inhibitory efficacies than antagonists and R. lignosus inoculated the same day. In the in vivo evaluation of fungi antagonists on R. lignosus, seedlings in H. jecorina treatment at 60 d and H. virens treatment at 150 d after inoculations respectively had the highest plant heaths (highest length of stem and length of tap rot, lowest plant death, and least foliar symptom) compared to the control. Mortality rate was higher at 60 d after inoculation and decline from the third months onward. Significant differences were observed between the control and R. lignosus treatment in all the parameters evaluated. PMID:25601145

  6. Isolation and molecular characterization of 1-aminocyclopropane-1-carboxylic acid synthase genes in Hevea brasiliensis.

    PubMed

    Zhu, Jia-Hong; Xu, Jing; Chang, Wen-Jun; Zhang, Zhi-Li

    2015-01-01

    Ethylene is an important factor that stimulates Hevea brasiliensis to produce natural rubber. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is a rate-limiting enzyme in ethylene biosynthesis. However, knowledge of the ACS gene family of H. brasiliensis is limited. In this study, nine ACS-like genes were identified in H. brasiliensis. Sequence and phylogenetic analysis results confirmed that seven isozymes (HbACS1-7) of these nine ACS-like genes were similar to ACS isozymes with ACS activity in other plants. Expression analysis results showed that seven ACS genes were differentially expressed in roots, barks, flowers, and leaves of H. brasiliensis. However, no or low ACS gene expression was detected in the latex of H. brasiliensis. Moreover, seven genes were differentially up-regulated by ethylene treatment. These results provided relevant information to help determine the functions of the ACS gene in H. brasiliensis, particularly the functions in regulating ethylene stimulation of latex production. PMID:25690030

  7. Hydroxynitrile lyase from Hevea brasiliensis: molecular characterization and mechanism of enzyme catalysis.

    PubMed

    Hasslacher, M; Kratky, C; Griengl, H; Schwab, H; Kohlwein, S D

    1997-03-01

    (S)-Hydroxynitrile lyase (Hnl) from the tropical rubber tree Hevea brasiliensis is a 29 kDa single chain protein that catalyses the breakdown or formation of a C--C bond by reversible addition of hydrocyanic acid to aldehydes or ketones. The primary sequence of Hnl has no significant homology to known proteins. Detailed homology investigations employing PROFILESEARCH and secondary structure prediction algorithms suggest that Hnl is a member of the alpha/beta hydrolase fold protein family and contains a catalytic triad as functional residues for catalysis. The significance of predicted catalytic residues was tested and confirmed by site-directed mutagenesis and expression of mutant and wild-type proteins in the yeast, Saccharomyces cerevisiae. Based on these data we suggest a mechanistic model for the (S)-cyanohydrin synthesis catalyzed by hydroxynitrile lyase from Hevea brasiliensis. PMID:9094745

  8. 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

  9. Genetic and epigenetic uniformity of polyembryony derived multiple seedlings of Hevea brasiliensis.

    PubMed

    Karumamkandathil, Rekha; Uthup, Thomas K; Sankaran, Sobha; Unnikrishnan, Divya; Saha, Thakurdas; Nair, Sushamakumari S

    2015-05-01

    Hevea brasiliensis Muell. Arg (Para rubber tree) is a tropical tree species of Amazonian origin widely cultivated in several parts of the world for natural rubber, a highly priced commodity inevitable for the world rubber industry. Large, tree to tree variation in growth and latex yield among individual plants of high yielding Hevea clones is a common phenomenon observed in mature rubber plantations. The genetic heterogeneity of the seedlings which are used as rootstocks for propagation through budgrafting is considered as a major factor responsible for this variation. In order to minimize this variation, attempts were made to develop highly uniform rootstock material via an in vitro technique by inducing zygotic polyembryony in Hevea. Immature open pollinated fruits of a high yielding clone RRII 105 were cultured by half ovulo embryo culture technique. Multiple embryos were induced from the 8-10-week-old zygote with a novel combination of gibberellic acid (GA3), kinetin, and zeatin. Plantlets were successfully generated from the multiple embryos and raised in the field post hardening. Screening using genetic and epigenetic molecular markers revealed that the multiple seedlings developed are highly uniform and are of single zygotic origin. Development of plants having genetic and epigenetic uniformity suggests that this technique is ideal for raising uniform rootstock material in Hevea which may significantly reduce intraclonal variations. Moreover, these plants could serve as ideal material for physiological and molecular investigations towards the understanding of stock-scion interaction process in rubber. PMID:25359186

  10. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. Molecular cloning, expression profiles and characterization of a glutathione reductase in Hevea brasiliensis.

    PubMed

    Deng, Zhi; Zhao, Manman; Liu, Hui; Wang, Yuekun; Li, Dejun

    2015-11-01

    Glutathione reductase (GR; EC 1.8.1.7) is an important oxidoreductase that can protect organisms against various oxidative stresses. In this study, a new GR gene, named as HbGR2, was isolated from Hevea brasiliensis. The HbGR2 cDNA contained a 1674-bp open reading frame encoding 557 amino acids and the deduced HbGR2 protein showed high identities to the chloroplastic GRs from other plant species. HbGR2 was localized in the chloroplasts of tobacco mesophyll protoplasts. The cis-acting regulatory elements related to stress or hormone responses were predicted in the promoter region of HbGR2. The results from real-time RT-PCR analyses showed that HbGR2 was expressed throughout different tissues and developmental stages of leaves. Besides being related to tapping panel dryness (TPD), HbGR2 was regulated by several treatments including ethephon (ET), methyl jasmonate (MeJA), drought, low temperature, high salt, wounding and hydrogen peroxide (H2O2). The Escherichia coli (E. coli) cells overexpressing HbGR2 markedly increased their tolerance and survival at high concentrations of H2O2, suggesting that HbGR2 might play an important role in oxidative stress response in Hevea brasiliensis. PMID:26232647

  13. 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

  14. Influence of soil, plant and meteorological factors on water relations and yield in Hevea brasiliensis

    NASA Astrophysics Data System (ADS)

    Rao, G. Gururaja; Rao, P. Sanjeeva; Rajagopal, R.; Devakumar, A. S.; Vijayakumar, K. R.; Sethuraj, M. R.

    1990-09-01

    Influence of factors governing the soil-plantatmosphere system on components of water relations and yield was studied in two clones of rubber tree, Hevea brasiliensis, viz. RRII 105 and RRII 118. Clonal variations were evident in yield and yield components and associated physiological parameters in response to soil moisture status and meteorological factors. Observations made during different seasons indicatedvariations in yield are attributed to differences in plugging index and initial flow rates, to the major yield components and also variations in components of water relations as influenced by meteorological factors. Among the two clones, RRII 105 was found to be fairly drought tolerant compared to RRII 118. RRII 105 was found to respond well to dry weather through higher stomatal resistances, higher leaf water potentials, lowered transpirational water loss and lower relative transpiration ratios, while RRII 118 was susceptible to stress situations.

  15. Climate and natural production of rubber ( Hevea brasiliensis) in Xishuangbanna, southern part of Yunnan province, China

    NASA Astrophysics Data System (ADS)

    Jiang, Ailiang

    1988-12-01

    According to the author's and his collaborators' investigations, the climate influences the growth of rubber trees ( Hevea brasiliensis) in Xishuangbanna, the southern part of Yunnan Province, China, in at least four aspects: (1) The yield of latex per tapping and the final yield of dry rubber per tree per year or per unit area per year; (2) the growth rate, as expressed by increment of girth in cm; (3) the survival during the over-wintering period; (4) the initiation or suppression of certain diseases; In this paper the author would like to describe the influence of climatic elements on yield of latex and on survival during the over-wintering period. As for the other two aspects, only general comments are given.

  16. 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. PMID:26787454

  17. 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

  18. Synchronous flowering of the rubber tree (Hevea brasiliensis) induced by high solar radiation intensity.

    PubMed

    Yeang, Hoong-Yeet

    2007-01-01

    How tropical trees flower synchronously near the equator in the absence of significant day length variation or other meteorological cues has long been a puzzle. The rubber tree (Hevea brasiliensis) is used as a model to investigate this phenomenon. The annual cycle of solar radiation intensity is shown to correspond closely with the flowering of the rubber tree planted near the equator and in the subtropics. Unlike in temperate regions, where incoming solar radiation (insolation) is dependent on both day length and radiation intensity, insolation at the equator is due entirely to the latter. Insolation at the upper atmosphere peaks twice a year during the spring and autumn equinoxes, but the actual solar radiation that reaches the ground is attenuated to varying extents in different localities. The rubber tree shows one or two flowering seasons a year (with major and minor seasons in the latter) in accordance with the solar radiation intensity received. High solar radiation intensity, and in particular bright sunshine (as distinct from prolonged diffuse radiation), induces synchronous anthesis and blooming in Hevea around the time of the equinoxes. The same mechanism may be operational in other tropical tree species. PMID:17587376

  19. Variation in GUS activity in vegetatively propagated Hevea brasiliensis transgenic plants.

    PubMed

    Lardet, Ludovic; Leclercq, Julie; Bénistan, Elise; Dessailly, Florence; Oliver, Gérald; Martin, Florence; Montoro, Pascal

    2011-10-01

    Hevea brasiliensis transgenic plants are regenerated from transgenic callus lines by somatic embryogenesis. Somatic embryogenesis is not yet available for commercial propagation of Hevea clones, which requires conventional grafting of buds on rootstock seedlings (budding). The stability of transgene expression in budded plants is therefore necessary for further development of genetic engineering in rubber trees. Transgene expression was assessed by fluorimetric beta-glucuronidase (GUS) activity in fully developed leaves of in vitro plants from transgenic lines and their sub-lines obtained by budding. A large variation in GUS activity was found in self-rooted in vitro plants of five transgenic lines, and the absence of activity in one line suggested transgene silencing. Beyond confirming transmissibility of the reporter gene by budding and long-term expression, a quantification of GUS activity revealed that greater variability existed in budded plants compared to self-rooted mother in vitro plants for three transgenic lines. Although somatic embryogenesis provided more stable GUS activity, budding remained an efficient way of propagating transgenic plants but transgene expression in budded plants should be verified for functional analysis and further development. PMID:21643815

  20. 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

    2015-01-01

    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

  1. [Coupling effects of water and chemical fertilizers on Hevea brasiliensis latex yield].

    PubMed

    Hua, Yuan-Gang; Chen, Qiu-Bo; Lin, Zhao-Mu; Luo, Wei

    2008-06-01

    Water and nutrient are the two main factors limiting Hevea brasiliensis growth and its latex yield. With 17 year-old Clone SCATC 7-33-97 H. brasiliensis as test material, the coupling effects of water and chemical N, P and K fertilizers on latex yield were studied by general orthogonal rotation design of quadratic regression with four factors and five levels under field condition, and a regressive mathematical model was set up based on the latex yield by quadratic regression analysis. The results showed that all test coupling levels of water and chemical fertilizers had significant effects on the latex yield. The yield-increasing effect of test factors was in the order of N application rate > irrigation amount > P application rate > K application rate, while the coupling effect of water and chemical fertilizers was in the sequence of water and N > N and P > water and P > water and K. There was a negative coupling effect of K application rate and soil moisture content. For latex yield, the optimum application rates of chemical fertilizers were 476.39 kg x hm(-2) of urea, 187.70 kg x hm(-2) of superphosphate and 225.77 kg x hm(-2) of potassium chloride, and the optimum irrigation amount was to have 82.78% soil relative water content. PMID:18808010

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

    PubMed

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

    2016-03-01

    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

  3. 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.

  4. 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

  5. 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. PMID:25019490

  6. 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

  7. 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. PMID:26287380

  8. 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. PMID:24239687

  9. 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. PMID:25906196

  10. 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

  11. Diversity of the cassiicolin gene in Corynespora cassiicola and relation with the pathogenicity in Hevea brasiliensis.

    PubMed

    Déon, Marine; Fumanal, Boris; Gimenez, Stéphanie; Bieysse, Daniel; Oliveira, Ricardo R; Shuib, Siti Shuhada; Breton, Frédéric; Elumalai, Sunderasan; Vida, João B; Seguin, Marc; Leroy, Thierry; Roeckel-Drevet, Patricia; Pujade-Renaud, Valérie

    2014-01-01

    Corynespora cassiicola is an important plant pathogenic Ascomycete causing the damaging Corynespora Leaf Fall (CLF) disease in rubber tree (Hevea brasiliensis). A small secreted glycoprotein named cassiicolin was previously described as an important effector of C. cassiicola. In this study, the diversity of the cassiicolin-encoding gene was analysed in C. cassiicola isolates sampled from various hosts and geographical origins. A cassiicolin gene was detected in 47 % of the isolates, encoding up to six distinct protein isoforms. In three isolates, two gene variants encoding cassiicolin isoforms Cas2 and Cas6 were found in the same isolate. A phylogenetic tree based on four combined loci and elucidating the diversity of the whole collection was strongly structured by the toxin class, as defined by the cassiicolin isoform. The isolates carrying the Cas1 gene (toxin class Cas1), all grouped in the same highly supported clade, were found the most aggressive on two rubber tree cultivars. Some isolates in which no Cas gene was detected could nevertheless generate moderate symptoms, suggesting the existence of other yet uncharacterized effectors. This study provides a useful base for future studies of C. cassiicola population biology and epidemiological surveys in various host plants. PMID:24433675

  12. Antioxidative polyphenols from Nigerian mistletoe Loranthus micranthus (Linn.) parasitizing on Hevea brasiliensis.

    PubMed

    Agbo, Matthias Onyebuchi; Lai, Daowan; Okoye, Festus B C; Osadebe, Patience O; Proksch, Peter

    2013-04-01

    Two new phenolic glycosides, linamarin gallate (1) and walsuraside B (2), together with nine known compounds, catechin (3), epicatechin (4), epicatechin 3-O-gallate (5), epicatechin 3-O-(3-O-methyl)gallate (6), epicatechin 3-O-(3,5-O-dimethyl)gallate (7), epicatechin 3-O-(3,4,5-O-trimethyl)gallate (8), quercetin 3-O-β-d-glucopyranoside (9), rutin (10), and peltatoside (11), were isolated from the leafy twigs of Nigerian mistletoe Loranthus micranthus (Linn.) parasitic on Hevea brasiliensis. Compound 1 was characterized as an unusual cyanogenic glycoside, while compound 8 was isolated for the first time from a natural source. This is the first report of a cyanogenic glycoside from mistletoes. The structures of the new compounds were unambiguously elucidated by 1D ((1)H, (13)C), 2D NMR (COSY, HSQC, and HMBC) and by mass spectroscopy. The antioxidant activities of the isolated compounds (1-11) were evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. PMID:23422225

  13. 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. PMID:26986200

  14. 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

  15. Relationship between latex yield of Hevea brasiliensis and antecedent environmental parameters

    NASA Astrophysics Data System (ADS)

    Raj, Shammi; Das, Gitali; Pothen, Jacob; Dey, Sushil Kumar

    2005-01-01

    A study on the relationship between latex yield and antecedent environmental data was undertaken for five clones (RRII203, RRII118, RRIM600, RRII105 and GT1) of Hevea brasiliensis (rubber) in Agartala, northeast India, a region in which rubber is not traditionally cultivated. The explained variance for the regression equations based on parameters determined on the day of tapping and up to 3 days prior to it, varied from 72% to 37% during the NWT period and 94 83% during the WT period. Soil moisture storage, 1 and 3 days prior to tapping, was found to be the primary parameter affecting yield for the NWT and WT periods, respectively. It was observed that the clone RRII105, with a comparatively lower yield to that of RRIM600, was more susceptible to daily WD conditions during the non-winter season. RRIM600 and RRII105 being high-yielding clones were also found to be fairly dependent on the AT of the day prior to tapping. The mean lag period correlation of this parameter with yield was also found to be higher during the WT period than during the NWT period. As a whole, the mean lag period based on prior measurements of environmental variables showed optimum correlation with yield at 15 20 days prior to the day of tapping. The study also confirms that varied responses of yield with environmental factors in this non-traditional region of rubber cultivation depend on clonal character.

  16. Hevea brasiliensis cell suspension peroxidase: purification, characterization and application for dye decolorization

    PubMed Central

    2013-01-01

    Peroxidases are oxidoreductase enzymes produced by most organisms. In this study, a peroxidase was purified from Hevea brasiliensis cell suspension by using anion exchange chromatography (DEAE-Sepharose), affinity chromatography (Con A-agarose) and preparative SDS-PAGE. The obtained enzyme appeared as a single band on SDS-PAGE with molecular mass of 70 kDa. Surprisingly, this purified peroxidase also had polyphenol oxidase activity. However, the biochemical characteristics were only studied in term of peroxidase because similar experiments in term of polyphenol oxidase have been reported in our pervious publication. The optimal pH of the purified peroxidase was 5.0 and its activity was retained at pH values between 5.0–10.0. The enzyme was heat stable over a wide range of temperatures (0–60°C), and less than 50% of its activity was lost at 70°C after incubation for 30 min. The enzyme was completely inhibited by β-mercaptoethanol and strongly inhibited by NaN3; in addition, its properties indicated that it was a heme containing glycoprotein. This peroxidase could decolorize many dyes; aniline blue, bromocresol purple, brilliant green, crystal violet, fuchsin, malachite green, methyl green, methyl violet and water blue. The stability against high temperature and extreme pH supported that the enzyme could be a potential peroxidase source for special industrial applications. PMID:23402438

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

    PubMed

    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

  18. 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

  19. 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

  20. Development, characterization, and cross-species/genera transferability of SSR markers for rubber tree (Hevea brasiliensis).

    PubMed

    Yu, Fei; Wang, Bao-Hua; Feng, Su-Ping; Wang, Jing-Yi; Li, Wei-Guo; Wu, Yao-Ting

    2011-03-01

    Genomic simple sequence repeat (SSR) markers are particularly valuable in studies of genetic diversity, evolution, genetic linkage map construction, quantitative trait loci tagging, and marker-assisted selection because of their multi-allelic nature, reproducibility, co-dominant inheritance, high abundance, and extensive genome coverage. The traditional methods of SSR marker development, such as genomic-SSR hybrid screening and microsatellite enrichment, have the disadvantages of high cost and complex operation. The selectively amplified microsatellite method is less costly and highly efficient as well as being simple and convenient. In this study, 252 sequences with SSRs were cloned from the rubber tree (Hevea brasiliensis) genome from which 258 SSR loci were obtained. The average repeat number was six. There were only 10 (3.9%) mononucleotide, trinucleotide, and pentanucleotide repeats, whereas the remaining 248 (96.1%) were dinucleotide repeats, including 128 (49.6%) GT/CA repeats, 118 (45.7%) GA/CT repeats, and 2 (0.8%) AT/TA repeats. A total of 126 primer pairs (see ESM) were successfully designed of which 36 primer pairs generated polymorphic products from 12 accessions of the cultivated species, 4 related species, and 3 species of the family Euphorbiaceae. In addition, investigations based on four genomic SSRs (GAR4, ACR22, CTR25, and GTR28) by cloning and sequencing provided evidence for cross-species/genera applicability, and homologous sequences were obtained from the rubber tree and Euphorbiaceae. Further analysis about the variation of the flanking regions of the four markers was carried out. PMID:20960206

  1. 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. PMID:27085600

  2. Catalytic mechanism of hydroxynitrile lyase from Hevea brasiliensis: a theoretical investigation.

    PubMed

    Cui, Feng-Chao; Pan, Xiao-Liang; Liu, Jing-Yao

    2010-07-29

    Density functional theory (DFT) calculations using the hybrid functional B3LYP have been performed to investigate the catalytic mechanism of hydroxynitrile lyase from Hevea brasiliensis (Hb-HNL). This enzyme catalyzes the cleavage of acetone cyanohydrin to hydrocyanic acid plus acetone. Two models (A and B) of the active site consisting of 105 and 155 atoms, respectively, were constructed on the basis of the crystal structure. Good consistency between the two models provides a verification of the proposed mechanism. Our calculations show that the catalytic reaction proceeds via three elementary steps: (1) deprotonation of the OH-Ser80 by His235 and concomitant abstraction of a proton from the substrate hydroxyl by Ser80; (2) the C-C bond cleavage of the acetone cyanohydrin; and (3) protonation of the cleaved cyanide by His235. The cleavage of the C-C bond is the rate-limiting step with the overall free energy barrier of 13.5 kcal/mol for relatively smaller model A (14.9 kcal/mol for a larger model B) in the protein environment, which is in good agreement with experimental rate. The present results give support to the previously proposed general acid/base catalytic mechanism, in which the catalytic triad acts as a general acid/base. Moreover, the calculated results for model C, with the positive charge of Lys236 removed from model A, show that Lys236 with the positive charge plays a vital role in lowering the reaction barrier of the rate-determining and helps in stabilizing the negatively charged CN(-) by forming a hydrogen bond with the substrate, consistent with the experimental analysis. PMID:20593768

  3. Molecular cloning and characterization of a Mlo gene in rubber tree (Hevea brasiliensis).

    PubMed

    Qin, Bi; Zheng, Fucong; Zhang, Yu

    2015-03-01

    Mlo gene encodes a plant-specific seven-transmembrane domain protein involved in a variety of cellular processes. In this study, a novel Mlo gene from rubber tree (Hevea brasiliensis), designated HbMlo1, was cloned by RT-PCR in rubber tree. The ORF of HbMlo1 was 1551bp in length, encoding a putative protein of 516 amino acids. HbMlo1 was a typical Mlo protein with seven-transmembrane domain. Sequence comparison between HbMlo1 and other Mlo proteins demonstrated that HbMlo1 shared the highest similarity with the Cucumis melo CmMlo1 and Arabidopsis thaliana AtMlo1 with 75.1% and 71.3% sequence identity, respectively. Phylogenetic analysis revealed that HbMlo1, CmMlo1, AtMlo1, AtMlo13, and AtMlo15 formed into the phylogenetic clade II with 100% bootstrap support value. HbMlo1 transcript exhibited tissue specificity, and it was preferentially expressed in leaf. Furthermore, the amount of HbMlo1 transcript was significantly induced by various phytohormones (including ethephon, methyl jasmonate, salicylic acid, abscisic acid, indole-3-acetic acid, and gibberellic acid), H2O2, and wounding treatments. Under drought stress, HbMlo1 exhibited a complex pattern of regulation. However, HbMlo1 expression did not significantly change during powdery mildew infection. These results suggested that HbMlo1 might play a role in phytohormone signaling and abiotic stress response processes in rubber tree. PMID:25506769

  4. 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.

  5. 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.

  6. 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

  7. 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. PMID:25017153

  8. 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. PMID:25048025

  9. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. ...

  11. Molecular characterization and expression analysis of the small GTPase ROP members expressed in laticifers of the rubber tree (Hevea brasiliensis).

    PubMed

    Qin, Yunxia; Huang, Yacheng; Fang, Yongjun; Qi, Jiyan; Tang, Chaorong

    2014-01-01

    ROP (Rho of plants) proteins are plant-specific Rho-type small GTPases which play important roles in cellular processes and stress responses. This study explores the characteristics and possible functions of ROPs that are expressed primarily in laticifers of the rubber tree (Hevea brasiliensis). The work serves as a preliminary step to determining their involvement in latex flow and regeneration, laticifers formation and tapping panel dryness (TPD, a physiological disorder in rubber trees that result in the stoppage of latex flow). In this connection, we (i) identified five HbROPs (HbROP1-HbROP5) by searching latex transcripts database and the genome databases, (ii) characterized molecular and phylogenic aspects of the HbROPs and examined the cis-regulatory elements in their promoter regions; (iii) analyzed by Real-time Quantitative PCR (QPCR) the tissue specificity of the HbROPs and their expression patterns in response to tapping, bark wounding and growth regulator treatments. All five HbROP genes were strongly expressed in the latex, with HbROP1, 3, 4 and 5 showing the highest expression among the six Hevea tissues examined, viz. latex, bud, mature leaf, bark, male flower and seed. When tapping was initiated on previously untapped trees, HbROP3 transcription was substantially down-regulated whereas HbROP5 expression was markedly up-regulated. Transcripts of HbROP3 rose gradually with the development of TPD. Except for the cytokinin 6-benzyl aminopurine that induced a rise in HbROP5 transcripts by more than 2-fold, the other growth regulators tested had little effect on HbROPs expression. The roles of HbROPs in rubber tree are discussed in relation to the diverse functions of ROP homologs reported in other plant species. PMID:24308989

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

    PubMed

    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

  13. 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

  14. Responses of Hevea brasiliensis Muell. Arg. plants to low temperatures under controlled conditions

    NASA Astrophysics Data System (ADS)

    de Lemos Filho, José Pires; Pinto, Hilton Silveira; da Rocha Neto, Olinto Gomes

    1993-12-01

    In this study we have examined the responses of Hevea plants to low temperatures in growth chambers simulating winter conditions in the tropics. The low temperatures increased the leaf diffusive resistance even with a rise in the leaf temperatures toward the end of day. The total chlorophyll levels were reduced by chilling, with no changes in the chlorophyll a/b ratio. Neither organic solute nor electrolyte leakage were observed at low temperatures. These results explain the low growth rate of plants and the lack of serious chilling symptoms (necrosis) in mature leaves during winter conditions near latitude 22° S in Brazil.

  15. High-level intracellular expression of hydroxynitrile lyase from the tropical rubber tree Hevea brasiliensis in microbial hosts.

    PubMed

    Hasslacher, M; Schall, M; Hayn, M; Bona, R; Rumbold, K; Lückl, J; Griengl, H; Kohlwein, S D; Schwab, H

    1997-10-01

    (S)-Hydroxynitrile lyase (Hnl) from the tropical rubber tree Hevea brasiliensis catalyzes the formation of (S)-cyanohydrins from hydrocyanic acid and aldehydes or ketones. This enzyme accepts aliphatic, aromatic, and heterocyclic carbonyl compounds as substrates and is therefore considered a potent biocatalyst for the industrial production of optically active chemicals. Limitations in enzyme supply from natural resources were overcome by production of the enzyme in the microbial host systems Escherichia coli, Saccharomyces cerevisiae, and Pichia pastoris. Expression of Hnl in the prokaryotic system led to the formation of inclusion bodies whereas in both yeast hosts high levels of soluble protein were obtained. Highest yields were obtained in a high cell density batch fermentation of a P. pastoris transformant that expressed heterologous Hnl to about 50% of the soluble cytosolic protein. At a cell density of 100 g/liter cell dry weight, a volume yield of 22 g/liter of heterologous product was obtained. Attempts to produce the Hnl protein extracellularly with the yeast hosts by applying different leader peptide strategies were not successful. Immunofluorescence microscopy studies indicated that the secretion-directed heterologous Hnl protein accumulated in the plasma membrane forming aggregated clusters of inactive protein. PMID:9325140

  16. Screening of bacterial biocontrols against sapstain fungus (Lasiodiplodia theobromae Pat.) of rubberwood (Hevea brasiliensis Muell.Arg.).

    PubMed

    Sajitha, K L; Maria Florence, E J; Dev, Suma Arun

    2014-09-01

    Diverse bacterial biocontrol agents from various sources of aerobic composts against the sapstain fungus Lasiodiplodia theobromae in rubberwood (Hevea brasiliensis) were isolated, screened and identified by various morphological, biochemical and molecular techniques. The inhibitory effect of seventeen bacterial isolates was examined and seven exhibited inhibition towards the sapstain fungus. Among the seven antagonists, six were conclusively identified as Bacillus subtilis and one as Paenibacillus polymyxa using 16S rRNA-encoding gene sequencing. This is the first report on the occurrence of P. polymyxa, a potent biofertilizer and antagonist in vermicompost. HiCrome Bacillus agar was identified as an effective medium for differentiation of B. subtilis from other Bacillus species. The present work demonstrates the efficacy of the antagonistic property of B. subtilis strains against rubberwood sapstain fungus. Culture-based antagonistic inhibition displayed by B. subtilis can be extended to cater to the biocontrol requirements of wood-based industries against the stain fungus. The study showed the utility of an integrated approach, employing morphological, biochemical and molecular tools for conclusive identification of several bacterial isolates present in aerobic composts from diverse sources. PMID:25049165

  17. 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. PMID:26854410

  18. Hevea brasiliensis prohevein possesses a conserved C-terminal domain with amyloid-like properties in vitro.

    PubMed

    Berthelot, Karine; Lecomte, Sophie; Coulary-Salin, Bénédicte; Bentaleb, Ahmed; Peruch, Frédéric

    2016-04-01

    Prohevein is a wound-induced protein and a main allergen from latex of Hevea brasiliensis (rubber tree). This 187 amino-acid protein is cleaved in two fragments: a N-terminal 43 amino-acids called hevein, a lectin bearing a chitin-binding motif with antifungal properties and a C-terminal domain (C-ter) far less characterized. We provide here new insights on the characteristics of prohevein, hevein and C-terminal domain. Using complementary biochemical (ThT/CR/chitin binding, agglutination) and structural (modeling, ATR-FTIR, TEM, WAXS) approaches, we show that this domain clearly displays all the characteristics of an amyloid-like proteins in vitro, that could confer agglutination activity in synergy with its chitin-binding activity. Additionally, this C-ter domain is highly conserved and present in numerous plant prohevein-like proteins or pathogenesis-related (PR and WIN) proteins. This could be the hallmark of the eventual presence of proteins with amyloid properties in plants, that could potentially play a role in defense through aggregation properties. PMID:26805576

  19. Cloning, heterologous expression and characterization of ascorbate peroxidase (APX) gene in laticifer cells of rubber tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Chao, Jinquan; Zhang, Shixin; Chen, Yueyi; Tian, Wei-Min

    2015-12-01

    Ascorbate peroxidases (APXs) are a kind of crucial enzymes for removing reactive oxygen species (ROS) in plant cell. In the present study, a full-length cDNA encoding an APX, designated HbAPX, was isolated from Hevea brasiliensis by the rapid amplification of cDNA ends (RACE) method. HbAPX was 1174-bp in length and contained a 912-bp open reading frame (ORF) encoding a putative protein of 304 amino acids. The predicted molecular mass of HbAPX was 27.6 kDa (kDa) with an isoelectric point (pI) of 6.73. The phylogenetic analysis showed that HbAPX belonged to the cytosolic subgroup and was more relative to PtAPX and MdAPX2. By using PlantCare online analysis, such cis-acting elements as W-box and MRE were detected in the promoter region of HbAPX. Overproduction of recombinant HbAPX protein either in Escherichia coli or yeast enhanced their tolerance to such abiotic stresses as Cu(2+), Zn(2+), Na(2+) and hydrogen peroxide (H2O2). Ethrel application significantly down-regulated the expression of HbAPX and inhibited the activity of HbAPX in vivo. The ethrel-caused down-regulation of HbAPX may disturb the redox homeostasis in laticifer cells of rubber tree. PMID:26519821

  20. 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

  1. 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

    2016-01-01

    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

  2. Base temperature and heat units for leaf flushing emission and growth of Hevea brasiliensis Muell. Arg.

    NASA Astrophysics Data System (ADS)

    de Lemos Filho, José Pires; Villa Nova, Nilson Augusto; Silveira Pinto, Hilton

    1993-06-01

    In this study we determined the base temperature and Heat units for leaf flushing initiation and growth of RRIM-600 and GT1 Hevea clones. The minimum base temperature was found to be approximately 16° C for leaf flushing emission and 19° C for shoot growth in terms of height. Approximately 420 degree days at 16° C as base temperature is required for successive leaf flushing initiation. Linear equations with correlation coefficients above 0.95 allow an estimation of the height increase from the accumulated degree days, corrected or otherwise for photoperiod. The highest correlation coefficients demonstrated a positive effect of the photoperiod among the factors influencing the shoot growth.

  3. 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. PMID:24891014

  4. 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. PMID:27068521

  5. 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

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

    PubMed

    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

  7. Identification and Characterization of the Glucose-6-Phosphate Dehydrogenase Gene Family in the Para Rubber Tree, Hevea brasiliensis

    PubMed Central

    Long, Xiangyu; He, Bin; Fang, Yongjun; Tang, Chaorong

    2016-01-01

    As a key enzyme in the pentose phosphate pathway (PPP), glucose-6-phosphate dehydrogenase (G6PDH) provides nicotinamide adenine dinucleotide phosphate (NADPH) and intermediary metabolites for rubber biosynthesis, and plays an important role in plant development and stress responses. In this study, four Hevea brasiliensis (Para rubber tree) G6PDH genes (HbG6PDH1 to 4) were identified and cloned using a genome-wide scanning approach. All four HbG6PDH genes encode functional G6PDH enzymes as shown by heterologous expression in E. coli. Phylogeny analysis and subcellular localization prediction show that HbG6PDH3 is a cytosolic isoform, while the other three genes (HbG6PDH1, 2 and 4) are plastidic isoforms. The subcellular locations of HbG6PDH3 and 4, two latex-abundant isoforms were further verified by transient expression in rice protoplasts. Enzyme activity assay and expression analysis showed HbG6PDH3 and 4 were implicated in PPP during latex regeneration, and to influence rubber production positively in rubber tree. The cytosolic HbG6PDH3 is a predominant isoform in latex, implying a principal role for this isoform in controlling carbon flow and NADPH production in the PPP during latex regeneration. The expression pattern of plastidic HbG6PDH4 correlates well with the degree of tapping panel dryness, a physiological disorder that stops the flow of latex from affected rubber trees. In addition, the four HbG6PDHs responded to temperature and drought stresses in root, bark, and leaves, implicating their roles in maintaining redox balance and defending against oxidative stress. PMID:26941770

  8. 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. PMID:26358051

  9. Identification and Characterization of the Glucose-6-Phosphate Dehydrogenase Gene Family in the Para Rubber Tree, Hevea brasiliensis.

    PubMed

    Long, Xiangyu; He, Bin; Fang, Yongjun; Tang, Chaorong

    2016-01-01

    As a key enzyme in the pentose phosphate pathway (PPP), glucose-6-phosphate dehydrogenase (G6PDH) provides nicotinamide adenine dinucleotide phosphate (NADPH) and intermediary metabolites for rubber biosynthesis, and plays an important role in plant development and stress responses. In this study, four Hevea brasiliensis (Para rubber tree) G6PDH genes (HbG6PDH1 to 4) were identified and cloned using a genome-wide scanning approach. All four HbG6PDH genes encode functional G6PDH enzymes as shown by heterologous expression in E. coli. Phylogeny analysis and subcellular localization prediction show that HbG6PDH3 is a cytosolic isoform, while the other three genes (HbG6PDH1, 2 and 4) are plastidic isoforms. The subcellular locations of HbG6PDH3 and 4, two latex-abundant isoforms were further verified by transient expression in rice protoplasts. Enzyme activity assay and expression analysis showed HbG6PDH3 and 4 were implicated in PPP during latex regeneration, and to influence rubber production positively in rubber tree. The cytosolic HbG6PDH3 is a predominant isoform in latex, implying a principal role for this isoform in controlling carbon flow and NADPH production in the PPP during latex regeneration. The expression pattern of plastidic HbG6PDH4 correlates well with the degree of tapping panel dryness, a physiological disorder that stops the flow of latex from affected rubber trees. In addition, the four HbG6PDHs responded to temperature and drought stresses in root, bark, and leaves, implicating their roles in maintaining redox balance and defending against oxidative stress. PMID:26941770

  10. 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

  11. 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. PMID:25615936

  12. 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

  13. 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

  14. Increasing the reaction rate of hydroxynitrile lyase from Hevea brasiliensis toward mandelonitrile by copying active site residues from an esterase that accepts aromatic esters.

    PubMed

    von Langermann, Jan; Nedrud, David M; Kazlauskas, Romas J

    2014-09-01

    The natural substrate of hydroxynitrile lyase from rubber tree (HbHNL, Hevea brasiliensis) is acetone cyanohydrin, but synthetic applications usually involve aromatic cyanohydrins such as mandelonitrile. To increase the activity of HbHNL toward this unnatural substrate, we replaced active site residues in HbHNL with the corresponding ones from esterase SABP2 (salicylic acid binding protein 2). Although this enzyme catalyzes a different reaction (hydrolysis of esters), its natural substrate (methyl salicylate) contains an aromatic ring. Three of the eleven single-amino-acid-substitution variants of HbHNL reacted more rapidly with mandelonitrile. The best was HbHNL-L121Y, with a kcat 4.2 times higher and high enantioselectivity. Site-saturation mutagenesis at position 121 identified three other improved variants. We hypothesize that the smaller active site orients the aromatic substrate more productively. PMID:25044660

  15. 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. PMID:25581169

  16. 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

  17. 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.

  18. Mites (Acari) of rubber trees (Hevea brasiliensis Muell. Arg., Euphorbiaceae) in Piracicaba, state of São Paulo, Brazil.

    PubMed

    De Vis, Raf M J; de Moraes, Gilberto J; Bellini, Marcos R

    2006-01-01

    This study determined the main mite species on rubber trees (clone RRIM-600) in Piracicaba, southeast of São Paulo State, from June 2002 to May 2003 and evaluated the possible relation between them. It was conducted in a plantation of 5 ha on 11 year old trees, 15 m high, surrounded with crops as pearl millet, cotton, bean or corn. Samples were taken monthly and consisted of five leaflets, five petioles (only from October 2002 on) and five terminal sections of twigs (10 cm) from 15 rubber trees. All mites of one leaflet, one petiole and one twig section of each plant were mounted for identification to genera/species to estimate the proportional occurrence of each species. A total of 84,850 mites belonging to 38 species of 34 genera and 16 families were found. Tydeidae was the family with the highest number of species (11), followed by Phytoseiidae and Stigmaeidae (4 each). The most abundant families were Eriophyidae, Tenuipalpidae and Tydeidae (totals of 43,023, 26,390 and 13,644 individuals, respectively). The highest population levels of the pest mites Calacarus heveae Feres and Tenuipalpus heveae Baker occurred at the end of the rainy season. The most abundant predators were Metaseiulus camelliae (Chant & Yoshida-Shaul), Amblyseius compositus Denmark & Muma and Euseius citrifolius Denmark & Muma. The predators could not prevent the increase of C. heveae and T. heveae from March on. However, their presence might have prevented an earlier increase and even higher levels of those mites. PMID:17352076

  19. 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

  20. 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.

  1. 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

  2. Functional Characterization of Hevea brasiliensis CRT/DRE Binding Factor 1 Gene Revealed Regulation Potential in the CBF Pathway of Tropical Perennial Tree.

    PubMed

    Cheng, Han; Cai, Haibin; Fu, Haitian; An, Zewei; Fang, Jialin; Hu, Yanshi; Guo, Dianjing; Huang, Huasun

    2015-01-01

    Rubber trees (Hevea brasiliensis) are susceptible to low temperature and therefore are only planted in the tropical regions. In the past few decades, although rubber trees have been successfully planted in the northern margin of tropical area in China, they suffered from cold injury during the winter. To understand the physiological response under cold stress, we isolated a C-repeat binding factor 1 (CBF1) gene from the rubber tree. This gene (HbCBF1) was found to respond to cold stress but not drought or ABA stress. The corresponding HbCBF1 protein showed CRT/DRE binding activity in gel shift experiment. To further characterize its molecular function, the HbCBF1 gene was overexpressed in Arabidopsis. The HbCBF1 over expression (OE) line showed enhanced cold resistance and relatively slow dehydration, and the expression of Arabidopsis CBF pathway downstream target genes, e.g. AtCOR15a and AtRD29a, were significantly activated under non-acclimation condition. These data suggest HbCBF1 gene is a functional member of the CBF gene family, and may play important regulation function in rubber tree. PMID:26361044

  3. A full picture of enzymatic catalysis by hydroxynitrile lyases from Hevea brasiliensis: protonation dependent reaction steps and residue-gated movement of the substrate and the product.

    PubMed

    Zhao, Yuan; Chen, Nanhao; Mo, Yirong; Cao, Zexing

    2014-12-28

    Hydroxynitrile lyases (HNLs) defend plants from herbivores and microbial attack by releasing cyanide from hydroxynitriles. The reverse process has been productively applied to bioorganic syntheses of pharmaceuticals and agrochemicals. To improve our understanding of the catalytic mechanism of HNLs, extensive ab initio QM/MM and classical MM molecular dynamics simulations have been performed to explore the catalytic conversion of cyanohydrins into aldehyde (or ketone) and HCN by hydroxynitrile lyases from Hevea brasiliensis (HbHNLs). It was found that the catalytic reaction approximately follows a two-stage mechanism. The first stage involves two fast processes including the proton abstraction of the substrate through a double-proton transfer and the C-CN bond cleavage, while the second stage concerns HCN formation and is rate-determining. The complete free energy profile exhibits a peak of ∼18 kcal mol(-1). Interestingly, the protonation state of Lys236 influences the efficiency of the enzyme only to some extent, but it changes the entire catalytic mechanism. The dynamical behaviors of substrate delivery and HCN release are basically modulated by the gate movement of Trp128. The remarkable exothermicity of substrate binding and the facile release of HCN may drive the enzyme-catalyzed reaction to proceed along the substrate decomposition efficiently. Computational mutagenesis reveals the key residues which play an important role in the catalytic process. PMID:25375265

  4. 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. PMID:26611161

  5. Functional Characterization of Hevea brasiliensis CRT/DRE Binding Factor 1 Gene Revealed Regulation Potential in the CBF Pathway of Tropical Perennial Tree

    PubMed Central

    Cheng, Han; Cai, Haibin; Fu, Haitian; An, Zewei; Fang, Jialin; Hu, Yanshi; Guo, Dianjing; Huang, Huasun

    2015-01-01

    Rubber trees (Hevea brasiliensis) are susceptible to low temperature and therefore are only planted in the tropical regions. In the past few decades, although rubber trees have been successfully planted in the northern margin of tropical area in China, they suffered from cold injury during the winter. To understand the physiological response under cold stress, we isolated a C-repeat binding factor 1 (CBF1) gene from the rubber tree. This gene (HbCBF1) was found to respond to cold stress but not drought or ABA stress. The corresponding HbCBF1 protein showed CRT/DRE binding activity in gel shift experiment. To further characterize its molecular function, the HbCBF1 gene was overexpressed in Arabidopsis. The HbCBF1 over expression (OE) line showed enhanced cold resistance and relatively slow dehydration, and the expression of Arabidopsis CBF pathway downstream target genes, e.g. AtCOR15a and AtRD29a, were significantly activated under non-acclimation condition. These data suggest HbCBF1 gene is a functional member of the CBF gene family, and may play important regulation function in rubber tree. PMID:26361044

  6. [Mites (Acari) from rubber trees (Hevea brasiliensis Muell. Arg., Euphorbiaceae) and spontaneous euphorbiaceous in rubber trees cultivation].

    PubMed

    Bellini, Marcos R; Feres, Reinaldo J F; Buosi, Renato

    2008-01-01

    Quarterly samples were done in 2001 on three rubber tree plantation in the northwest of the state of São Paulo. Three rubber trees of each locality were sampled. Between the rows of rubber tree four species of spontaneous euphorbiaceous were collected: Chamaesyce hirta, C. hyssopifolia, Euphorbia heterophylla and Phyllanthus tenellus. A total of 8.954 mites of 38 species, belonging to 31 genera of 11 families were collected. Tydeidae and Phytoseiidae had the highest diversity of species, 9 and 7, respectively. The most abundant families were Eriophyidae (3.594), Tydeidae (2.825) and Tenuipalpidae (1.027). The most abundant species on the rubber trees were: phytophagous - Calacarus heveae Feres, Tenuipalpus heveae Baker, Lorryia sp.2, Lorryia formosa Cooreman and Lorryia sp.1; predators - Zetzellia quasagistemas Hernandes & Feres, Pronematus sp., Iphiseiodes zuluagai Denmark & Muma and Euseius citrifolius Denmark & Muma. Among the spontaneous euphorbiaceous, predatory mites were abundantly found on C. hirta and E. heterophylla, mainly Pronematus sp. and E. citrifolius, suggesting that these plants could be important in the maintenance of these predators in the rubber tree cultivation areas. However, plants that can shelter predators and at the same time exert strong competition (nutrients, water etc) to rubber trees, can not be recommended for pest management programs. Studies about competition between rubber trees and spontaneous plants need to be conducted for feasible efficient programs of environmental management, aiming at the control of pest mites of rubber tree. PMID:18813750

  7. 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. PMID:21761492

  8. 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

  9. 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. PMID:26074933

  10. Comparative study of two GH19 chitinase-like proteins from Hevea brasiliensis, one exhibiting a novel carbohydrate-binding domain.

    PubMed

    Martínez-Caballero, Siseth; Cano-Sánchez, Patricia; Mares-Mejía, Israel; Díaz-Sánchez, Angel G; Macías-Rubalcava, Martha L; Hermoso, Juan A; Rodríguez-Romero, Adela

    2014-10-01

    Plants express chitinase and chitinase-like proteins (CLPs) belonging to the glycosyl hydrolases of the GH18 and GH19 families, which exhibit varied functions. CLPs in the GH18 family have been structurally and functionally characterized; however, there are no structures available for any member of the GH19 family. In this study, two CLPs of the GH19 family from the rubber tree Hevea brasiliensis (HbCLP1 and HbCLP2) were cloned, expressed and characterized. HbCLP1 was identical to the allergen Hev b 11.0101 previously described by others, while HbCLP2 was a novel isoform exhibiting an unusual half chitin-binding domain before the catalytic domain. Sequence alignments showed that in the two proteins the catalytic residues Glu117 and Glu147 in HbCLP1 and HbCLP2, respectively, were mutated to Ala, accounting for the lack of activity. Nonetheless, both CLPs bound chitin and chitotriose (GlcNAc)3 with high affinities, as evaluated with chitin-affinity chromatography and tryptophan fluorescence experiments. The chitin-binding domains also bound chitotriose with even higher affinities. The crystal structures of the HbCLP1-isolated domains were determined at high resolution. The analysis of the crystallographic models and docking experiments using (GlcNAc)6 oligosaccharides provides evidence of the residues involved in sugar binding. Endochitinase activity was restored in both proteins by mutating residues A117E (HbCLP1) and A147E (HbCLP2); the distance between the catalytic proton donor and the catalytic nucleophile in the in silico mutated residues was 9.5 Å, as occurs in inverting enzymes. HbCLP1 and HbCLP2 were highly thermostable and exhibited antifungal activity against Alternaria alternata, suggesting their participation in plant defense mechanisms. PMID:25104038

  11. 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. PMID:25858315

  12. 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

    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

  13. 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

  14. 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.

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

    PubMed

    Nedrud, David M; Lin, Hui; Lopez, Gilsinia; Padhi, Santosh K; Legatt, Graig A; Kaz-Lauskas, Romas J

    2014-11-01

    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 the

  16. 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

  17. 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

  18. 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

  19. 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. PMID:25927524

  20. 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

  1. Mites (Arachnida: Acari) collected on rubber trees Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg. in Santana, Amapá state, Brazil.

    PubMed

    Deus, E G; Souza, M S M; Mineiro, J L C; Adaime, R; Santos, R S

    2012-11-01

    The purpose of this study was to elaborate a preliminary list of the mite species associated with rubber trees in the municipality of Santana, in the state of Amapá, Brazil. Two collections of rubber tree leaves were conducted on May 2nd and June 5th , 2010. Twenty-five plants were sampled at random. Three leaves were collected per plant, from the lower third of the crown. The samples were placed in paper bags, packed in an isothermal box chilled gel-based pulp plant (Gelo-X(®)), and transported to the Entomology Laboratory at Embrapa Amapá, in Macapá. The leaflets were examined under a stereomicroscope, and the mites found on the adaxial and abaxial surfaces of the leaves were collected with a stilet, mounted on microscope slides in Hoyer's medium, and later identified. We collected a total of 1,722 mites of 10 families: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae, and Winterschmidtiidae, in addition to unidentified species of the suborders Oribatida and Astigmatina. The family Phytoseiidae represented only 2.90% of specimens collected, but showed the highest species richness (5 species). The only representative of Tenuipalpidae was Tenuipalpus heveae Baker, 1945, but 81.13% of the mites collected in this study belonged to this species. PMID:23295522

  2. Hevea Linamarase—A Nonspecific β-Glycosidase 1

    PubMed Central

    Selmar, Dirk; Lieberei, Reinhard; Biehl, Böle; Voigt, Jürgen

    1987-01-01

    In the leaf tissue of the cyanogenic plant Hevea brasiliensis, which contains large amounts of linamarin, there is no specific linamarase. In Hevea leaves only one β-glucosidase is detectable. It is responsible for the cleavage of all β-glucosides and β-galactosides occurring in Hevea leaf tissue, including the cyanogenic glucoside linamarin. Therefore, the enzyme is referred to as a β-glycosidase instead of the term β-glucosidase. This β-glycosidase has a broad substrate spectrum and occurs in multiple forms. These homo-oligomeric forms are interconvertible by dissociation-association processes. The monomer is a single protein of 64 kilodaltons. PMID:16665288

  3. Hevea Linamarase-A Nonspecific beta-Glycosidase.

    PubMed

    Selmar, D; Lieberei, R; Biehl, B; Voigt, J

    1987-03-01

    In the leaf tissue of the cyanogenic plant Hevea brasiliensis, which contains large amounts of linamarin, there is no specific linamarase. In Hevea leaves only one beta-glucosidase is detectable. It is responsible for the cleavage of all beta-glucosides and beta-galactosides occurring in Hevea leaf tissue, including the cyanogenic glucoside linamarin. Therefore, the enzyme is referred to as a beta-glycosidase instead of the term beta-glucosidase. This beta-glycosidase has a broad substrate spectrum and occurs in multiple forms. These homo-oligomeric forms are interconvertible by dissociation-association processes. The monomer is a single protein of 64 kilodaltons. PMID:16665288

  4. QTL Mapping of Growth-Related Traits in a Full-Sib Family of Rubber Tree (Hevea brasiliensis) Evaluated in a Sub-Tropical Climate

    PubMed Central

    Mantello, Camila Campos; Silva, Carla Cristina; Garcia, Dominique; Le Guen, Vincent; Cardoso, Saulo Emilio Almeida; Garcia, Antonio Augusto Franco; Souza, Anete Pereira

    2013-01-01

    The rubber tree (Hevea spp.), cultivated in equatorial and tropical countries, is the primary plant used in natural rubber production. Due to genetic and physiological constraints, inbred lines of this species are not available. Therefore, alternative approaches are required for the characterization of this species, such as the genetic mapping of full-sib crosses derived from outbred parents. In the present study, an integrated genetic map was obtained for a full-sib cross family with simple sequence repeats (SSRs) and expressed sequence tag (EST-SSR) markers, which can display different segregation patterns. To study the genetic architecture of the traits related to growth in two different conditions (winter and summer), quantitative trait loci (QTL) mapping was also performed using the integrated map. Traits evaluated were height and girth growth, and the statistical model was based in an extension of composite interval mapping. The obtained molecular genetic map has 284 markers distributed among 23 linkage groups with a total length of 2688.8 cM. A total of 18 QTLs for growth traits during the summer and winter seasons were detected. A comparison between the different seasons was also conducted. For height, QTLs detected during the summer season were different from the ones detected during winter season. This type of difference was also observed for girth. Integrated maps are important for genetics studies in outbred species because they represent more accurately the polymorphisms observed in the genitors. QTL mapping revealed several interesting findings, such as a dominance effect and unique segregation patterns that each QTL could exhibit, which were independent of the flanking markers. The QTLs identified in this study, especially those related to phenotypic variation associated with winter could help studies of marker-assisted selection that are particularly important when the objective of a breeding program is to obtain phenotypes that are adapted to sub

  5. 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

  6. 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

    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 by

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  8. Histochemical and immunohistochemical identification of laticifer cells in callus cultures derived from anthers of Hevea brasiliensis.

    PubMed

    Tan, Deguan; Sun, Xuepiao; Zhang, Jiaming

    2011-06-01

    Laticifers are highly specialized cells present in over 20 plant families. They are well defined in planta. In vitro development of laticifers was also observed in some plants, but uncertain in the callus cultures of rubber tree, one of the most economically important latex producing plants. In the present study, we provide evidence that laticifer cells present in the callus cultures of rubber tree by histochemical and immunohistochemical studies. They present in the callus mainly as separate non-elongated form, a novel morphology different from the morphology of laticifer cells in planta, excluding their origin from explants. The occurring frequency of laticifer cells in the callus was genotype-dependent and negatively correlated with the somatic embryogenetic ability, suggesting that the presence of laticifer cells in the callus inhibit somatic embryogenesis in tissue culture of rubber tree. The genotypes PR107, RRIM600, Reyan8-79, and Reyan7-33-97 with lower embryogenetic ability compared to Haiken 2 had more laticifer cells, and laticifer clusters were only observed in these genotypes. PMID:21301851

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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. PMID:23894456

  14. Physiological and molecular responses to drought stress in rubber tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Wang, Li-feng

    2014-10-01

    Plant drought stress response and tolerance are complex biological processes. In order to reveal the drought tolerance mechanism in rubber tree, physiological responses and expressions of genes involved in energy biosynthesis and reactive oxygen species (ROS) scavenging were systematically analyzed following drought stress treatment. Results showed that relative water content (RWC) in leaves was continuously decreased with the severity of drought stress. Wilting leaves were observed at 7 day without water (dww). Total chlorophyll content was increased at 1 dww, but decreased from 3 dww. However, the contents of malondialdehyde (MDA) and proline were significantly increased under drought stress. Peroxidase (POD) and superoxide dismutase (SOD) activities were markedly enhanced at 1 and 3 dww, respectively. Meanwhile, the soluble sugar content was constant under drought stress. These indicated that photosynthetic activity and membrane lipid integrity were quickly attenuated by drought stress in rubber tree, and osmoregulation participated in drought tolerance mechanism in rubber tree. Expressions of energy biosynthesis and ROS scavenging systems related genes, including HbCuZnSOD, HbMnSOD, HbAPX, HbCAT, HbCOA, HbATP, and HbACAT demonstrated that these genes were significantly up-regulated by drought stress, and reached a maximum at 3 dww, then followed by a decrease from 5 dww. These results suggested that drought stress adaption in rubber tree was governed by energy biosynthesis, antioxidative enzymes, and osmoregulation. PMID:25194774

  15. 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. PMID:24793160

  16. 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

    2016-01-01

    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

  17. 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.

  18. 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

  19. Cytotaxonomy of the Brasiliensis subcomplex and the Triatoma brasiliensis complex (Hemiptera: Reduviidae: Triatominae).

    PubMed

    Alevi, Kaio C C; Rosa, João A; Azeredo-Oliveira, Maria Tercília V

    2014-01-01

    We analyzed the classical cytotaxonomy of the Brasiliensis subcomplex (Triatoma brasiliensis Neiva, T. juazeirensis Costa & Felix, T. melanica Costa, Argolo & Felix, T. melanocephala Neiva & Pinto, T. petrochiae Pinto & Barreto, T. lenti Sherlock & Serafim, T. sherlocki Papa, Jurberg, Carcavallo, Cerqueira & Barata, T. tibiamaculata Pinto and T. vitticeps Stal) and the T. brasiliensis complex (T. b. brasiliensis, T. b. macromelasoma Neiva & Lent, T. juazeirensis, T. melanica and T. sherlocki). The five members of the T. brasiliensis complex share the same cytogenetic characteristics. Merely T. sherlocki show differences in spermatids, which confirms the status of more differentiated member of the complex. T. lenti also presented the same cytogenetic characteristics described for the species of the T. brasiliensis complex, which supports possible grouping of the species as sixth member of the complex, although further analysis as molecular and experimental crosses are needed to corroborate this hypothesis. T. petrochiae, T. vitticeps, T. tibiamaculata and T. melanocephala presented one or more characteristics that allow questioning grouping in the proposed Brasiliensis subcomplex. Thus, we suggested that Brasiliensis subcomplex and T. brasiliensis complex should be constituted by the same triatomines (T. b. brasiliensis, T. b. macromelasoma, T. juazeirensis, T. melanica and T. sherlocki). However, we draw attention to T. lenti and suggest that although new analyzes should be performed, possibly this species is the sixth member of the T. brasiliensis complex.  PMID:25081800

  20. 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

  1. 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.

  2. 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. PMID:26298387

  3. 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. PMID:25905590

  4. Characteristics of environmental Paracoccidioides brasiliensis isolates.

    PubMed

    Costa, Patricia Fagundes; Fernandes, Geisa Ferreira; dos Santos, Priscila Oliveira; Amaral, Cristiane Candida; Camargo, Zoilo Pires

    2010-01-01

    The ecological niche or exact habitat of the fungus Paracoccidioides brasiliensis is not known, and few isolates have been obtained from the environment. In this study, ten isolates were analyzed with respect to antigenic composition, serology, pathogenicity, and molecular aspects. Gp43 is considered to be the molecular basis for the serodiagnosis of paracoccidioidomycosis; however, in this study only six of the environmental isolates secreted this molecule (four in great amounts and two in small amounts). Other molecules were also produced. When exoantigens from these isolates were tested using immunodiffusion, only four preparations were positive by ID tests. However, when these exoantigens were tested by ELISA, all of them except one were able to detect anti-P. brasiliensis antibodies. In Western blot assays, these exoantigens showed different reactivities. Isolates that secreted gp43 presented positive reactions for this molecule, and isolates that did not secrete gp43 gave positive reactions for other minor molecules. RAPD analysis revealed that there is great genetic variation between these environmental isolates. These isolates were non-pathogenic: no mortality was observed among the inoculated mice during an 18-month follow-up period. PMID:19653119

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  6. ASTM D1076 CATEGORY 4 LATEX AND QUANTIFYING GUAYULE (NRG) AND HEVEA (NR) LATEX PROTEIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Guayule latex is commercially available as a low protein natural rubber latex (Yulex®) which does not contain any protein that can be detected by the ASTM D6499 antigenic protein standard developed to quantify Hevea natural rubber latex (NRL) antigenic protein. In this paper, we discuss how best to...

  7. [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. PMID:11119321

  8. [Spatial distribution of Tenuipalpus heveae Baker (Acari: Tenuipalpidae) on rubber tree plantations].

    PubMed

    Martins, Gustavo L M; Vieira, Marineide R; Barbosa, José C; Dini, Thiago A; Manzano, Anderson M; Alves, Bruno M S; Silva, Rodolfo M

    2010-01-01

    The objective of this work was to study the spatial distribution of Tenuipalpus heveae Baker in rubber tree plantations. The experimental area was located in Marinópolis, State of São Paulo, and corresponded to a total of 1,000 plants (clone RRIM 600) divided in 100 plots of ten plants each. A total of 16 samplings were conducted, approximately once every 10 days, between December 2007 and June 2008. On each date, samples were taken from two plants per plot, each sample corresponding to the top 30 cm of a branch randomly taken from the median region of the canopy of each plant. The number of T. heveae was evaluated on three leaflets randomly taken from each sample, using a 20x power pocket magnifying glass. The number of mites was evaluated in two areas of 1 cm² delimited on the lower surface of each leaflet, being one along the midrib and the other along a lateral vein. The calculated dispersion indexes were: variance/mean relationship (I), index of Morisita (I´), coefficient of Green (Cx) and k exponent of negative binomial distribution. Tenuipalpus heveae showed aggregate distribution. The negative binomial distribution model was the most appropriate to represent the spatial distribution of the mite in the rubber tree plantation. PMID:21120376

  9. 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

  10. 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

  11. 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. PMID:16724848

  12. Monoclonal antibodies to Nocardia asteroides and Nocardia brasiliensis antigens.

    PubMed Central

    Jiménez, T; Díaz, A M; Zlotnik, H

    1990-01-01

    Nocardia asteroides and Nocardia brasiliensis whole-cell extracts were used as antigens to generate monoclonal antibodies (MAbs). Six stable hybrid cell lines secreting anti-Nocardia spp. MAbs were obtained. These were characterized by enzyme-linked immunosorbent assay, Western blot (immunoblot), and immunofluorescence assay. Although all the MAbs exhibited different degrees of cross-reactivity with N. asteroides and N. brasiliensis antigens as well as with culture-filtrate antigens from Mycobacteria spp., they have the potential for use as reagents in the purification of Nocardia antigens. Images PMID:2405017

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

    PubMed

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-01-01

    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. PMID:27395963

  14. 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. PMID:25964712

  15. 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. PMID:27419133

  16. 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

  17. 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.

  18. Paracoccidioides brasiliensis infection in domestic rabbits (Oryctolagus cuniculus).

    PubMed

    Belitardo, Donizeti Rodrigues; Calefi, Atilio Sersun; Sbeghen, Mônica Raquel; de Oliveira, Gabriela Gonçalves; Watanabe, Maria Angelica Ehara; de Camargo, Zoilo Pires; Ono, Mario Augusto

    2014-04-01

    The objective of this study was to evaluate the infection of domestic rabbits by Paracoccidioides brasiliensis. Initially two rabbits were experimentally infected with P. brasiliensis and the humoral immune response was evaluated by ELISA using gp43 as antigen. The two animals showed IgG response against gp43 although no signs of disease were observed. The seroepidemiological study was carried out in 170 rabbits (free range n = 81 and caged n = 89) living in an endemic area for human paracoccidioidomycosis and a positivity of 27% was observed in the ELISA using gp43 as antigen. The free-range rabbits showed a significantly higher positivity (34.6-51.7%) than the caged animals (11.1%). Sentinel rabbits exposed to natural infection with P. brasiliensis were followed up for 6 months and a seroconversion rate of 83.3% was observed. This is the first report of paracoccidioidomycosis in rabbits and suggests that this species can be useful sentinels for P. brasiliensis presence in the environment. PMID:24125519

  19. Temporal dynamics of reproduction in Hemiramphus brasiliensis (Osteichthyes: Hemiramphidae).

    PubMed

    de Oliveira, Mônica Rocha; Chellappa, Sathyabama

    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

  20. ANIMAL MODEL OF NIPPOSTRONGYLUS BRASILIENSIS AND HELIGMOSOMOIDES POLYGYRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal models of Nippostrongylus brasiliensis and Heligmosomoides polygyrus infection are powerful tools for the investigation of the basic biology of immune responses and protective immunity. In particular they model the induction and maintenance of Th2 type immune responses and exhibiting all the ...

  1. 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

  2. 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

  3. Sequential sampling plan for Tenuipalpus heveae Baker (Acari: Tenuipalpidae) on rubber tree.

    PubMed

    Martins, G L M; Vieira, M R; Barbosa, J C

    2013-04-01

    The objective of the present study was to develop a sequential sampling plan for the decision-making process to control Tenuipalpus heveae Baker (Acari: Tenuipalpidae), an important pest of the rubber tree crop. The experimental area was represented by 1,000 plants of the RRIM 600 clone divided in 100 plots with 10 plants each. Leaves were collected and the number of mites determined under laboratory conditions. The sequential sampling plan was developed in accordance with the Sequential Test Likelihood Ratio. The value 0.10 was pre-established for α and β representing type I and type II errors, respectively. The level of control adopted was six mites per 12 cm(2). The operating characteristic curve and the curve of maximum expected sample were determined. Two lines were generated: the upper one, when the condition for chemical control is recommended (S1 = 23.3080 + 2.1972); and the lower, when chemical control is not recommended (S0 = -23.3080 + 2.1972). Sample size for the decision-making process to control T. heveae requires 6 to 18 plants. PMID:23949755

  4. 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

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

    PubMed

    Arantes, Thales Domingos; Bagagli, Eduardo; Niño-Vega, Gustavo; San-Blas, Gioconda; Theodoro, Raquel Cordeiro

    2015-09-01

    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

  6. Extracellular Paracoccidioides brasiliensis phospholipase B involvement in alveolar macrophage interaction

    PubMed Central

    2010-01-01

    Background Phospholipase B (PLB) has been reported to be one of the virulence factors for human pathogenic fungi and has also been described as necessary for the early events in infection. Based on these data, we investigated the role of PLB in virulence and modulation of the alveolar pulmonary immune response during infection using an in-vitro model of host-pathogen interaction, i.e. Paracoccidioides brasiliensis yeast cells infecting alveolar macrophage (MH-S) cells. Results The effect of PLB was analyzed using the specific inhibitor alexidine dihydrochloride (0.25 μM), and pulmonary surfactant (100 μg mL-1), during 6 hours of co-cultivation of P. brasiliensis and MH-S cells. Alexidine dihydrochloride inhibited PLB activity by 66% and significantly decreased the adhesion and internalization of yeast cells by MH-S cells. Genes involved in phagocytosis (trl2, cd14) and the inflammatory response (nfkb, tnf-α, il-1β) were down-regulated in the presence of this PLB inhibitor. In contrast, PLB activity and internalization of yeast cells significantly increased in the presence of pulmonary surfactant; under this condition, genes such as clec2 and the pro-inflammatory inhibitor (nkrf) were up-regulated. Also, the pulmonary surfactant did not alter cytokine production, while alexidine dihydrochloride decreased the levels of interleukin-10 (IL-10) and increased the levels of IL-12 and tumor necrosis factor-α (TNF-α). In addition, gene expression analysis of plb1, sod3 and icl1 suggests that P. brasiliensis gene re-programming is effective in facilitating adaptation to this inhospitable environment, which mimics the lung-environment interaction. Conclusion P. brasiliensis PLB activity is involved in the process of adhesion and internalization of yeast cells at the MH-S cell surface and may enhance virulence and subsequent down-regulation of macrophage activation. PMID:20843362

  7. Ecotopes, natural infection and trophic resources of Triatoma brasiliensis (Hemiptera, Reduviidae, Triatominae).

    PubMed

    Costa, J; de Almeida, J R; Britto, C; Duarte, R; Marchon-Silva, V; Pacheco, R da S

    1998-01-01

    Triatoma brasiliensis is considered as one of the most important Chagas disease vectors in the northeastern Brazil. This species presents chromatic variations which led to descriptions of subspecies, synonymized by Lent and Wygodzinsky (1979). In order to broaden bionomic knowledge of these distinct colour patterns of T. brasiliensis, captures were performed at different sites, where the chromatic patterns were described: Caicó, Rio Grande do Norte (T. brasiliensis brasiliensis Neiva, 1911), it will be called the "brasiliensis population"; Espinosa, Minas Gerais (T. brasiliensis melanica Neiva & Lent 1941), the "melanica population" and Petrolina, Pernambuco (T. brasiliensis macromelasoma, Galvão 1956), the "macromelasoma population". A fourth chromatic pattern was collected in Juazeiro, Bahia the darker one in overall cuticle coloration, the "Juazeiro population". At the sites of Caicó, Petrolina and Juazeiro, specimens were captured in peridomiciliar ecotopes and in wilderness. In Espinosa the specimens were collected only in wilderness, even though several exhaustive captures have been performed in peridomicile at different sites of this municipality. A total of 298 specimens were captured. The average registered infection rate was 15% for "brasiliensis population" and of 6.6% for "melanica population". Specimens of "macromelasoma" and of "Juazeiro populations" did not present natural infection. Concerning trophic resources, evaluated by the precipitin test, feeding eclecticism for the different colour patterns studied was observed, with dominance of goat blood in household surroundings as well as in wilderness. PMID:9698835

  8. 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

  9. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  11. 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. PMID:10725590

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

    PubMed

    Renshaw, Mark A; Douglas, Kory C; Rexroad Iii, Caird E; Jobity, Ann Marie C; Gold, John R

    2009-05-01

    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 (eight tetranucleotide and two dinucleotide) and three imperfect repeats (two tetranucleotide and one dinucleotide). An additional five microsatellites, isolated originally from two congeneric species (S. cavalla and S. niphonius), were characterized in S. brasiliensis. Serra Spanish mackerel support artisanal fisheries along the Caribbean and Atlantic coasts of Central and South America, from Belize to Brazil. PMID:21564761

  13. 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

  14. In Vitro Activities of the New Antitubercular Agents PA-824 and BTZ043 against Nocardia brasiliensis

    PubMed Central

    Campos-Rivera, Mayra Paola; Gonzalez-Martinez, Norma Alejandra; Ocampo-Candiani, Jorge; Cole, Stewart T.

    2012-01-01

    The in vitro activity of PA-824 and BTZ043 against 30 Nocardia brasiliensis isolates was tested. The MIC50 and MIC90 values for PA-824 were both >64 μg/ml. The same values for BTZ043 were 0.125 and 0.250 μg/ml. Given the MIC values for benzothiazinone (BTZ) compounds, we consider them good candidates to be tested in vivo against N. brasiliensis. PMID:22526312

  15. In vitro activities of the new antitubercular agents PA-824 and BTZ043 against Nocardia brasiliensis.

    PubMed

    Vera-Cabrera, Lucio; Campos-Rivera, Mayra Paola; Gonzalez-Martinez, Norma Alejandra; Ocampo-Candiani, Jorge; Cole, Stewart T

    2012-07-01

    The in vitro activity of PA-824 and BTZ043 against 30 Nocardia brasiliensis isolates was tested. The MIC(50) and MIC(90) values for PA-824 were both >64 μg/ml. The same values for BTZ043 were 0.125 and 0.250 μg/ml. Given the MIC values for benzothiazinone (BTZ) compounds, we consider them good candidates to be tested in vivo against N. brasiliensis. PMID:22526312

  16. Complete mitochondrial genome of Salminus brasiliensis (Characiformes, Characidae).

    PubMed

    Brandão-Dias, Pedro Ferreira Pinto; Carmo, Anderson Oliveira do; Martins, Ana Paula Vimieiro; Pimenta, Ricardo José Gonzaga; Alves, Carlos Bernardo Mascarenhas; Kalapothakis, Evanguedes

    2016-05-01

    We report the complete mitochondrial genome of the fish Salminus brasiliensis, popularly known as dourado. It is a circular, 17,721 bp long DNA molecule, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a non-coding Control Region of 2128 bp, a relatively large molecule when compared to other closely related fishes. All protein-coding genes are on the heavy strand, except for Nd6, and all have ATG as the start codon, except for Cox1 gene which has a GTG start codon. Seven protein-coding genes have incomplete stop codons (Nd2, Cox2, Atp6, Nd4, and Cytb have T- -, and Cox3 and Nd3 have TA-). TAG is the stop codon for Nd6 and AGG is the stop codon for Cox1. PMID:25208163

  17. Drimanes from Drimys brasiliensis with leishmanicidal and antimalarial activity

    PubMed Central

    Claudino, Vanessa Duarte; da Silva, Kesia Caroline; Cechinel, Valdir; Yunes, Rosendo Augusto; Monache, Franco Delle; Giménez, Alberto; Salamanca, Efrain; Gutierrez-Yapu, David; Malheiros, Angela

    2013-01-01

    This paper evaluates CHCl3 and CH3OH extracts of the stem bark, branches and leaves of Drimys brasiliensis and drimane sesquiterpenes isolated from the stem bark against strains of Leishmania amazonensis and Leishmania braziliensis promastigotes and Plasmodium falciparum trophozoites. All of the extracts and compounds were tested in cell lines in comparison with reference standards and cell viability was determined by the XTT method. The CHCl3 and CH3OH extracts from the stem bark and branches yielded promising results against two strains of Leishmania, with 50% inhibitory concentrations (IC50 ) values ranging from 39-100 µg/mL. The CHCl3 extract of the stem bark returned IC50 values of 39 and 40.6 µg/mL for L. amazonensis and L. braziliensis, respectively. The drimanes were relatively effective: 1-β-(p-coumaroyloxy)-polygodial produced IC50 values of 5.55 and 2.52 µM for L. amazonensis and L. braziliensis, respectively, compared with 1-β-(p-methoxycinnamoyl)-polygodial, which produced respective IC50 values of 15.85 and 17.80 µM. The CHCl3 extract demonstrated activity (IC50 of 3.0 µg/mL) against P. falciparum. The IC50 values of 1-β-(p-cumaroyloxyl)-polygodial and 1-β-(p-methoxycinnamoyl)-polygodial were 1.01 and 4.87 µM, respectively, for the trophozoite strain. Therefore, the results suggest that D. brasiliensis is a promising plant from which to obtain new and effective antiparasitic agents. PMID:23579790

  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. 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

    2013-01-01

    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

  1. 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

  2. Exocellular components of Paracoccidioides brasiliensis: identification of a specific antigen.

    PubMed Central

    Puccia, R; Schenkman, S; Gorin, P A; Travassos, L R

    1986-01-01

    Yeast forms of Paracoccidioides brasiliensis grown in liquid medium produced exocellular components. Immunodiffusion reactions and immunoprecipitations of 131I-radiolabeled antigenic components with sera from patients having paracoccidioidomycosis (PCM) were used to monitor the isolation of specific constituents. Components having the main antigenic activity (fCon A) were isolated by exclusion from a Bio-Gel P30 column, followed by successive binding of eluted material to a Sepharose-concanavalin A column, and elution. The product contained, from sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, a minor 43,000-molecular-weight (MW) component (gp43), a polydisperse high-MW glycoconjugate, and a diffusely migrating 55,000-MW glycoprotein (gp55). Other components, including a 72,000-MW glycoprotein, were irregularly expressed. The high-MW glycoconjugate complex contained, on the basis of methylation and 13C nuclear magnetic resonance data, a branched structure of mainly mannopyranosyl units. These were nonreducing ends, 6-O-, 2-O-, and 2,6-di-O-substituted, and the specific rotation of +16 degrees indicated that the glycosidic configurations of the units were alpha and beta in a ratio of ca. 1:1 (concanavalin A binding indicated that nonreducing ends or 2-O-substituted units or both of alpha-D-mannopyranose were present). A small proportion of nonreducing end units of D-galactopyranose were also present in this polysaccharide. gp55 is a glycoprotein containing a complex carbohydrate moiety with fucose, mannose, galactose, and glucose, either as terminal nonreducing units or substituted in positions indicated by methylation data. Both PCM and normal human sera precipitated the high-MW glycoconjugate from 131I-labeled fCon A preparations, whereas gp55 was unreactive with human sera. gp43 was a specific antigenic component of P. brasiliensis culture filtrates which could be isolated in a pure form by gel filtration column chromatography (Sephadex G150

  3. 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. PMID:26520796

  4. Sensitive immunoradiometric assay for the detection of Paracoccidioides brasiliensis antigens in human sera.

    PubMed Central

    Ferreira-da-Cruz, M F; Galvão-Castro, B; Daniel-Ribeiro, C T

    1991-01-01

    In the present study we report the standardization of an immunoradiometric assay (IRMA) for detection of Paracoccidioides brasiliensis circulating antigens that could be useful in the diagnosis and prognosis of paracoccidioidomycosis. For this purpose we studied the reactivities of P. brasiliensis and other mycotic antigens with rabbit polyclonal anti-P. brasiliensis antibodies (immunoglobulin G) in order to evaluate the sensitivity and specificity of an IRMA for detecting P. brasiliensis antigens. The results were compared with those obtained by the double immunodiffusion test, the standard technique for the serodiagnosis of paracoccidioidomycosis. By using the immunoglobulin G fraction of rabbit antisera (900 ng per well), it was possible to detect up to 3.6 ng (0.12 micrograms/ml) of cellular antigen and 360 ng (12 micrograms/ml) of metabolic antigen in contrast to the double immunodiffusion test that could detect only 12 micrograms (1.2 mg/ml) of both antigens. IRMA was shown to be feasible and very sensitive and may therefore help, together with clinical data, in establishing early diagnosis and assessing disease activity. It could also allow the study of relationships between P. brasiliensis circulating antigens and host defense mechanisms during the disease. PMID:1907608

  5. 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. PMID:26273267

  6. Lymphocutaneous Nocardia brasiliensis infection acquired from a cat scratch: case report and review.

    PubMed

    Sachs, M K

    1992-10-01

    Nocardia brasiliensis is a bacterium that is most commonly found in the soil. Traumatic inoculation of N. brasiliensis into the skin is the most typical mode of acquisition of infection due to this organism. To the best of my knowledge, I report the first case of lymphocutaneous N. brasiliensis disease from a penetrating cat scratch of the skin, thereby establishing cats as vehicles for the transmission of this infection. Treatment with penicillin produced a rapid resolution of all signs and symptoms of infection. The efficacy of penicillin against the N. brasiliensis isolate recovered from this patient was highly unusual. In general, penicillin has limited therapeutic value since these organisms elaborate beta-lactamase. Sulfonamides remain the drugs of choice for the treatment of these infections. These soil-borne organisms are most likely carried on the claws of cats and may establish infection after percutaneous inoculation. A high index of suspicion for N. brasiliensis soft-tissue infection is required since a delayed or missed diagnosis may be associated with progressive local disease and/or widespread disseminated infection. PMID:1420688

  7. 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

  8. Reconstructing the locomotor repertoire of Protopithecus brasiliensis. I. Body size.

    PubMed

    Halenar, Lauren B

    2011-12-01

    An accurate body size estimate is essential for reconstructing and interpreting many aspects of the paleobiology of an extinct taxon. With this in mind, the purpose of this study is two-fold: first, to create statistically robust predictive regression equations for body mass, total body length, and head and body length from postcranial elements using a platyrrhine reference sample, data that do not exist elsewhere in the literature; and, second, to apply those regression equations to the "giant" subfossil platyrrhine Protopithecus brasiliensis, a little-studied taxon represented by a nearly complete skeleton. Building on results of previous work with other primate groups, different skeletal elements, subgroups of the reference sample, and regression models lead to different body size estimates with different standard errors and prediction errors. However, relatively tight clusters of estimates around 20 kg, total length of 1,675 mm, and head and body length of 710 mm are obtained, placing the fossil in the size range of a large male baboon. While not quite as large as the original 25 kg body mass estimate for the fossil, this new estimate is still approximately 150% larger than the largest living New World monkey. Confirmation of its place in a large-bodied size class of platyrrhines has a profound effect on reconstructing the locomotor repertoire of Protopithecus and the evolutionary trajectory of the alouattin lineage. PMID:22042663

  9. 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. PMID:26404561

  10. Natural products from Garcinia brasiliensis as Leishmania protease inhibitors.

    PubMed

    Pereira, Ivan O; Assis, Diego M; Juliano, Maria A; Cunha, Rodrigo L O R; Barbieri, Clara L; do Sacramento, Luis V S; Marques, Marcos J; dos Santos, Marcelo H

    2011-06-01

    The infections by protozoans of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials, which cause renal and cardiac toxicity. As part of a search for new drugs against leishmaniasis, we evaluated the in vitro Leishmania protease inhibition activity of extracts (hexanic, ethyl-acetate, and ethanolic) and fukugetin, a bioflavonoid purified from the ethyl-acetate extract of the pericarp of the fruit of Garcinia brasiliensis, a tree native to Brazilian forests. The isolated compound was characterized by using spectral analyses with nuclear magnetic resonance, mass spectroscopy, ultraviolet, and infrared techniques. The ethyl-acetate extract and the compound fukugetin showed significant activity as inhibitors of Leishmania's proteases, with mean (±SD) IC(50) (50% inhibition concentration of protease activity) values of 15.0±1.3 μg/mL and 3.2±0.5 μM/mL, respectively, characterizing a bioguided assay. In addition, this isolated compound showed no activity against promastigote and amastigote forms of L. (L.) amazonensis and mammalian cells. These results suggest that fukugetin is a potent protease inhibitor of L. (L.) amazonensis and does not cause toxicity in mammalian or Leishmania cells in vitro. This study provides new perspectives on the development of novel drugs that have leishmanicidal activity obtained from natural products and that target the parasite's proteases. PMID:21554130

  11. New iridoid glucosides from the aerial parts of Verbena brasiliensis.

    PubMed

    Ono, Masateru; Oishi, Kanna; Abe, Hiroaki; Masuoka, Chikako; Okawa, Masafumi; Ikeda, Tsuyoshi; Nohara, Toshihiro

    2006-10-01

    Two new iridoid glucosides, verbenabraside A (1) and verbenabraside B (2), were isolated from the aerial parts of Verbena brasiliensis VELL., along with six known iridoid glucosides, gelsemiol 3-O-beta-D-glucoside (3), verbraside (4), 9-hydroxysemperoside (5), griselinoside (6), aralidioside (7), and 6alpha-hydroxyforsythide dimethyl ester (8), three known phenylethanoid glycosides, 2-phenylethyl O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (9), acteoside (10), and leucosceptoside A (11), two known lignan glucosides, dihydroxymethyl-bis(3,5-dimethoxy-4-hydroxyphenyl) tetrahydrofuran-9 (or 9')-O-beta-glucopyranoside (12) and (+)-lyoniresinol 3alpha-O-beta-D-glucopyranoside (13), a known methyl salicylate glucoside, methyl 2-O-beta-D-glucopyranosylbenzoate (14), and two known sterols, beta-sitosterol 3-O-beta-D-glucopyranoside (15) and beta-sitosterol (16). Their chemical structures were determined on the basis of spectroscopic data. Compound 1 exhibited stronger scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl than that of alpha-tocopherol. PMID:17015981

  12. 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

  13. Preparation of species-specific murine monoclonal antibodies against the yeast phase of Paracoccidioides brasiliensis.

    PubMed Central

    Figueroa, J I; Hamilton, A J; Bartholomew, M A; Harada, T; Fenelon, L; Hay, R J

    1990-01-01

    A panel of four murine monoclonal antibodies showing species specificity for the yeast phase of the pathogenic dimorphic fungus Paracoccidioides brasiliensis was produced by using a modification of the standard monoclonal antibody technology. This involved the use of the immunosuppressive drug cyclophosphamide to suppress the immune response of test animals to fungi showing cross-reactivity, i.e., to Histoplasma capsulatum. One monoclonal antibody, P4, which had a high titer by enzyme-linked immunosorbent assay, was shown to recognize a linear antigenic epitope of P. brasiliensis at a molecular size of 70,000 to 75,000 daltons by Western blot (immunoblot) analysis. The potential use of these monoclonal antibodies, which are the first species-specific probes to P. brasiliensis that have been produced, in the field of serodiagnosis is discussed. Images PMID:2394802

  14. Increase in virulence of Sporothrix brasiliensis over five years in a patient with chronic disseminated sporotrichosis

    PubMed Central

    Freitas, Dayvison FS; Santos, Suelen S; Almeida-Paes, Rodrigo; de Oliveira, Manoel ME; do Valle, Antonio CF; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely M; Nosanchuk, Joshua d

    2015-01-01

    Abstract 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. PMID:25668479

  15. 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. PMID:26787143

  16. 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

  17. 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. PMID:18278348

  18. 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. PMID:11418327

  19. 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

  20. 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

  1. 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

  2. Therapeutic effect of Agaricus brasiliensis on phenylhydrazine-induced neonatal jaundice in rats.

    PubMed

    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

  3. 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

  4. Activation of the alternative complement pathway in canine normal serum by Paracoccidioides brasiliensis.

    PubMed

    Bianchini, A A C; Petroni, T F; Fedatto, P F; Bianchini, R R; Venancio, E J; Itano, E N; Ono, M A

    2009-04-01

    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

  5. Decreased expression of 14-3-3 in Paracoccidioides brasiliensis confirms its involvement in fungal pathogenesis.

    PubMed

    Marcos, Caroline Maria; Silva, Julhiany de Fátima ds; Oliveira, Haroldo Cesar de; 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

  6. Topical anti-inflammatory activity of Eugenia brasiliensis Lam. (Myrtaceae) leaves.

    PubMed

    Pietrovski, Evelise Fernandes; Magina, Michele Debiasi Alberton; Gomig, Franciane; Pietrovski, Caroline Fernandes; Micke, Gustavo Amadeu; Barcellos, Michele; Pizzolatti, Moacir Geraldo; Cabrini, Daniela Almeida; Brighente, Inês Maria Costa; Otuki, Michel Fleith

    2008-04-01

    Eugenia brasiliensis Lam., a plant from the south of Brazil, is used in the popular medicine for rheumatism treatment. This study reports that topical application of hydroalcoholic extract, fractions and isolated compounds from E. brasiliensis caused an inhibition of ear oedema in response to topical application of croton oil on the mouse ear. For oedema inhibition, the estimated ID50 values (dose reducing the inflammatory response by 50% relative to the control value) for hydroalcoholic extract and fractions (hexane, ethyl acetate and dichloromethane) were 0.17, 0.29, 0.13 and 0.14 mg/ear, respectively, with inhibition of 79+/-7%, 87+/-6%, 88+/-5% and 96+/-2%, respectively. Isolated phenolic compounds (quercetin, catechin and gallocatechin) were also effective in inhibiting the oedema (inhibition of 61+/-5%, 66+/-2% and 37+/-9%, respectively). Moreover, both extract and isolated compounds caused inhibition of polymorphonuclear cells influx (inhibition of 85+/-6%, 81+/-5%, 73+/-6% and 76+/-6%, respectively). The histological analysis of the ear tissue clearly confirmed that the extract and compounds of E. brasiliensis inhibited the influx of polymorphonuclear cells to mouse ear skin after application of croton oil. Furthermore, hydroalcoholic extract was also effective in inhibiting the arachidonic acid-mediated mouse ear oedema (ID50 value was 1.94 mg/ear and inhibition of 60+/-7%). Therefore, these results consistently support the notion that E. brasiliensis possesses topical anti-inflammatory activity. PMID:18380921

  7. 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

  8. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Cerataphis brasiliensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. Do different degrees of human activity affect the diet of Brazilian silverside Atherinella brasiliensis?

    PubMed

    Alves, V E N; Patrício, J; Dolbeth, M; Pessanha, A; Palma, A R T; Dantas, E W; Vendel, A L

    2016-08-01

    The aim of the present study was to test whether different degrees of human activity affect the diet of the Brazilian silverside Atherinella brasiliensis in two tropical estuaries. Fish were collected along the salinity gradient of two Brazilian estuaries, the heavily impacted Paraiba Estuary and the less impacted Mamanguape Estuary, in the dry and wet seasons. The findings confirm that A. brasiliensis has generalist feeding habits and is able to change its diet under different environmental conditions. The results indicate clear spatial (i.e. along the estuarine gradient) changes in diet composition in both estuaries, but diet was also influenced by the degree of anthropogenic disturbance. During the wet season in the nutrient enriched Paraiba Estuary, when human activity was higher, the diet of A. brasiliensis was poorer and dominated by few dietary items, reflecting the potential impoverishment of prey items in this heavily disturbed system. The specimens collected in the most affected estuary also had a greater frequency of micro-plastics and parasites in their stomachs, reflecting the greater degree of human disturbance in the estuary. The present findings suggest that the diet of A. brasiliensis could be a useful indicator of changes in the ecological quality of these and other tropical estuaries of the western Atlantic Ocean. PMID:27328827

  10. 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.

  11. Initial development of the endocarp in Lithraea brasiliensis Marchand (Anacardiaceae): with taxonomic notes.

    PubMed

    De Oliveira, João M S; Mariath, Jorge E A

    2015-09-01

    Investigation into the initial developmental stages of a given structure is fundamental for precise characterization as well as for comparative analysis in relation to other taxa when homologies are established. For the Anacardiaceae family, investigations of the initial development of the pericarp or its basic histological sites, the epicarp, mesocarp and endocarp, are relevant since these regions are of taxonomic and phylogenetic importance. The initial stages of endocarp development in Lithraea brasiliensis were studied using light microscopy. In L. brasiliensis, the fruits are of the drupe type. The endocarp originates exclusively in the epidermis of the locular cavity and is composed of only three strata. The crystalliferous layer, typical in fruits of the Anacardiaceae family, originates in the carpelar mesophyll and runs adjacent to the outermost layer of the endocarp. The endocarp in Lithraea brasiliensis is of the Anacardium type. The results of the present study are important for the identification of the Lithraea species that occur in the state of Rio Grande do Sul. In L. molleoides, the crystalliferous layer was shown to originate from the locular epidermis and this developmental aspect enables it to be differentiated from L. brasiliensis and demonstrates that there is variability of endocarp development in Lithraea. PMID:26221992

  12. 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

  13. Thermal preferences and limits of Triatoma brasiliensis in its natural environment - Field observations while host searching

    PubMed Central

    Catalá, Silvia; Bezerra, Claudia Mendonça; Diotaiuti, Lileia

    2015-01-01

    The goal of this work was to explore the thermal relationship between foraging Triatoma brasiliensis and its natural habitat during the hottest season in the state of Ceará, Brazil. The thermal profiles were determined using infrared analysis. Although the daily temperature of rock surfaces varied in a wide range, T. brasiliensis selected to walk through areas with temperatures between 31.7-40.5ºC. The temperature of T. brasiliensis body surface ranged from 32.8-34.4ºC, being higher in legs than the abdomen. A strong relationship was found between the temperature of the insect and the temperature of rock crevices where they were hidden (r: 0.96, p < 0.05). The species was active at full sunlight being a clear example of how the light-dark rhythm may be altered, even under predation risk. Our results strongly suggest a thermal borderline for T. brasiliensis foraging activity near 40ºC. The simultaneous determination of insect body and rock temperatures here presented are the only obtained in natural habitats for this or other triatomines. PMID:26517659

  14. IL-13 receptor alpha-2 regulates the immune and functional response to Nippostrongylus brasiliensis infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. 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

  16. Epidemiology of Ornithodoros brasiliensis (mouro tick) in the southern Brazilian highlands and the description of human and animal retrospective cases of tick parasitism.

    PubMed

    Reck, José; Marks, Fernanda S; Guimarães, Jorge A; Termignoni, Carlos; Martins, João Ricardo

    2013-02-01

    Ornithodoros brasiliensis, also known as the "mouro" tick, is an argasid tick found exclusively in the southern Brazilian highlands. O. brasiliensis parasitism is frequently associated with severe symptoms directly induced by the tick bite, a condition compatible with the definition of tick toxicosis. The objectives of this work include (i) the determination of the distribution of O. brasiliensis in farms located in the tick-endemic region, (ii) the description of the characteristics of O. brasiliensis habitats, (iii) the analysis of risk factors associated with O. brasiliensis, and (iv) the retrospective description of cases of human and animal parasitism by O. brasiliensis. Of the 30 farms included in this study, O. brasiliensis was identified on 5 farms (frequency 16.7%), in which several ticks found in high density buried in soil were collected. Information regarding the tick habitats and the local population was recorded. The data indicated that O. brasiliensis feeds on humans, dogs, armadillos (Dasypus hybridus), and possibly skunks (Conepatus chinga). The analysis of risk factors indicated that the presence of house basements with an unpaved (natural soil) floor on farms and insufficient sanitary conditions significantly enhanced the probability of identifying O. brasiliensis. Additionally, we describe retrospectively cases of tick parasitism in 28 humans and 11 dogs including the most common symptoms associated with tick toxicosis. This is the first study concerning O. brasiliensis epidemiology, distribution, and habitat, and the report represents the most comprehensive characterization of Ornithodoros bite-associated toxicosis syndrome. PMID:23238249

  17. 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

    2015-01-01

    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. PMID:26345830

  18. 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.

  19. 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

    2016-01-01

    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. PMID:26241825

  20. 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

  1. Immunity-dependent reduction of segmented filamentous bacteria in mice infected with the helminthic parasite Nippostrongylus brasiliensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. 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

  3. 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. PMID:26381537

  4. 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. PMID:25619570

  5. 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. PMID:27524995

  6. Paracoccidioides brasiliensis Enolase Is a Surface Protein That Binds Plasminogen and Mediates Interaction of Yeast Forms with Host Cells ▿

    PubMed Central

    Nogueira, Sarah Veloso; Fonseca, Fernanda L.; Rodrigues, Marcio L.; Mundodi, Vasanth; Abi-Chacra, Erika A.; Winters, Michael S.; Alderete, John F.; Soares, Célia Maria de Almeida

    2010-01-01

    Paracoccidioidomycosis (PCM), caused by the dimorphic fungus Paracoccidioides brasiliensis, is a disseminated, systemic disorder that involves the lungs and other organs. The ability of the pathogen to interact with host components, including extracellular matrix (ECM) proteins, is essential to further colonization, invasion, and growth. Previously, enolase (EC 4.2.1.11) was characterized as a fibronectin binding protein in P. brasiliensis. Interaction of surface-bound enolase with plasminogen has been incriminated in tissue invasion for pathogenesis in several pathogens. In this paper, enolase was expressed in Escherichia coli as a recombinant glutathione S-transferase (GST) fusion protein (recombinant P. brasiliensis enolase [rPbEno]). The P. brasiliensis native enolase (PbEno) was detected at the fungus surface and cytoplasm by immunofluorescence with an anti-rPbEno antibody. Immobilized purified rPbEno bound plasminogen in a specific, concentration-dependent fashion. Both native enolase and rPbEno activated conversion of plasminogen to plasmin through tissue plasminogen activator. The association between PbEno and plasminogen was lysine dependent. In competition experiments, purified rPbEno, in its soluble form, inhibited plasminogen binding to fixed P. brasiliensis, suggesting that this interaction required surface-localized PbEno. Plasminogen-coated P. brasiliensis yeast cells were capable of degrading purified fibronectin, providing in vitro evidence for the generation of active plasmin on the fungus surface. Exposure of epithelial cells and phagocytes to enolase was associated with an increased expression of surface sites of adhesion. In fact, the association of P. brasiliensis with epithelial cells and phagocytes was increased in the presence of rPbEno. The expression of PbEno was upregulated in yeast cells derived from mouse-infected tissues. These data indicate that surface-associated PbEno may contribute to the pathogenesis of P. brasiliensis. PMID

  7. 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. PMID:10892986

  8. 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. PMID:25524512

  9. 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

  10. 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

  11. 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

  12. 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. PMID:1573521

  13. Microsatellites for Carpotroche brasiliensis (Flacourtiaceae), a useful species for agroforestry and ecosystem conservation1

    PubMed Central

    Bittencourt, Flora; Alves, Jackeline S.; Gaiotto, Fernanda A.

    2015-01-01

    Premise of the study: We developed microsatellite markers for Carpotroche brasiliensis (Flacourtiaceae), a dioecious tree that is used as a food resource by midsize animals of the Brazilian fauna. Methods and Results: We designed 30 primer pairs using next-generation sequencing and classified 25 pairs as polymorphic. Observed heterozygosity ranged from 0.5 to 1.0, and expected heterozygosity ranged from 0.418 to 0.907. The combined probability of exclusion was greater than 0.999 and the combined probability of identity was less than 0.001, indicating that these microsatellites are appropriate for investigations of genetic structure, individual identification, and paternity testing. Conclusions: The developed molecular tools may contribute to future studies of population genetics, answering ecological and evolutionary questions regarding efficient conservation strategies for C. brasiliensis. PMID:26697275

  14. Disseminated Sporothrix brasiliensis Infection with Endocardial and Ocular Involvement in an HIV-Infected Patient

    PubMed Central

    Silva-Vergara, Mario León; de Camargo, Zoilo Pires; Silva, Patricia Ferreira; Abdalla, Michel Reis; Sgarbieri, Ricardo Nilsson; Rodrigues, Anderson Messias; dos Santos, Keila Cristina; Barata, Cristina Hueb; Ferreira-Paim, Kennio

    2012-01-01

    Disseminated sporotrichosis occurs in individuals with impaired cellular immunity, such as in cases of neoplasia, transplantation, diabetes, and especially, acquired immunodeficiency syndrome. This report presents a 32-year-old Brazilian human immunodeficiency virus (HIV)-infected patient who developed a protracted condition of disseminated sporotrichosis with endocarditis, bilateral endophthalmitis, and lymphatic involvement. He needed cardiac surgery to replace the mitral valve. Sporothrix brasiliensis isolates were recovered from cultures of subcutaneous nodules and mitral valve fragments. Species identification was based on classical and molecular methods. The patient received amphotericin B for 52 days and subsequently, oral itraconazole. He remains asymptomatic, and he is on maintenance therapy with itraconazole. Despite his positive clinical outcome, he developed bilateral blindness. To our knowledge, this case is the first report of endocarditis and endophthalmitis caused by S. brasiliensis. PMID:22403321

  15. Performance and meat quality of broiler chickens that are fed diets supplemented with Agaricus brasiliensis mushrooms.

    PubMed

    Guimarães, João Borges; Dos Santos, Eder Clementino; Dias, Eustáquio Souza; Bertechini, Antônio Gilberto; da Silva Ávila, Carla Luiza; Dias, Francesca Silva

    2014-12-01

    This trial was performed to study the use of the mushroom Agaricus brasiliensis as an alternative additive to antimicrobial growth promoters in broiler chicken diets and to assess the quality of the broiler chicken breast meat of birds that are fed diets containing this fungus. Thus, 595 1-day-old chicks were reared in reused poultry litter without anticoccidial and antimicrobial additives. The results showed that a concentration of 1.6 g mushrooms/kg diet was ideal for these birds because it provided better bird performance. When the birds' immune system organs were analyzed, it was found that the addition of both mushrooms influenced the immune system organs of these broiler chickens. Adding A. brasiliensis to broiler chicken diets did not compromise breast meat quality. PMID:25169695

  16. PARTICLE SIZE INVESTIGATION ON NATURAL RUBBER FROM DIFFERENT CLONES OF BRAZILIAN IAC SERIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hevea brasiliensis species are being investigated in order to increase the production of natural rubber and to develop new clones more appropriate to specific soil and climate. Particle size of natural rubber from Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. - Arg. coming from new clones from...

  17. 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

  18. Antifungal activity of fractions and two pure compounds of flowers from Wedelia paludosa (Acmela brasiliensis) (Asteraceae).

    PubMed

    Sartori, M R K; Pretto, J B; Cruz, A B; Bresciani, L F V; Yunes, R A; Sortino, M; Zacchino, S A; Cechinel, V Filho

    2003-08-01

    Wedelia paludosa (Acmela brasiliensis) (Asteraceae), a traditionally used native Brazilian medicinal plant, showed antifungal activity against dermatophytes in dilution tests. The hexane, dichloromethane and butanol fractions displayed activity against Epidermophyton floccosum, Trichophyton rubrum and Trichophyton mentagrophytes, with minimal inhibitory concentrations between 250 and 1000 microg/mL. Two pure compounds, identified as kaurenoic acid (1) and luteolin (2), also showed activity against these dermatophytes. PMID:12967035

  19. Immunological Basis for the Gender Differences in Murine Paracoccidioides brasiliensis Infection

    PubMed Central

    Pinzan, Camila Figueiredo; Ruas, Luciana Pereira; Casabona-Fortunato, Anália Sulamita; Carvalho, Fernanda Caroline; Roque-Barreira, Maria-Cristina

    2010-01-01

    This study aimed to investigate the immunological mechanisms involved in the gender distinct incidence of paracoccidioidomycosis (pcm), an endemic systemic mycosis in Latin America, which is at least 10 times more frequent in men than in women. Then, we compared the immune response of male and female mice to Paracoccidioides brasiliensis infection, as well as the influence in the gender differences exerted by paracoccin, a P. brasiliensis component with carbohydrate recognition property. High production of Th1 cytokines and T-bet expression have been detected in the paracoccin stimulated cultures of spleen cells from infected female mice. In contrast, in similar experimental conditions, cells from infected males produced higher levels of the Th2 cytokines and expressed GATA-3. Macrophages from male and female mice when stimulated with paracoccin displayed similar phagocytic capability, while fungicidal activity was two times more efficiently performed by macrophages from female mice, a fact that was associated with 50% higher levels of nitric oxide production. In order to evaluate the role of sexual hormones in the observed gender distinction, we have utilized mice that have been submitted to gonadectomy followed by inverse hormonal reconstitution. Spleen cells derived from castrated males reconstituted with estradiol have produced higher levels of IFN-γ (1291±15 pg/mL) and lower levels of IL-10 (494±38 pg/mL), than normal male in response to paracoccin stimulus. In contrast, spleen cells from castrated female mice that had been treated with testosterone produced more IL-10 (1284±36 pg/mL) and less IFN-γ (587±14 pg/mL) than cells from normal female. In conclusion, our results reveal that the sexual hormones had a profound effect on the biology of immune cells, and estradiol favours protective responses to P. brasiliensis infection. In addition, fungal components, such as paracoccin, may provide additional support to the gender dimorphic immunity that marks P

  20. Morphological studies on the infraciliature of a planktonic ciliate, Tintinnopsis brasiliensis (Ciliophora: Tintinina)

    NASA Astrophysics Data System (ADS)

    Cai, Shengfang; Song, Weibo; Xu, Dapeng; Chiang, Kuoping

    2006-01-01

    A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid & Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation after protargol impregnation and was compared with other related congeners. According to the infraciliature, three ciliary groups can be recognized, which reveals a very stable structure among specimens and denotes that the pattern of infraciliature is, apart from the features of the lorica, a highly reliable criterion for species identification.

  1. 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

  2. Response of Paracoccidioides brasiliensis Pb01 to stressor agents and cell wall osmoregulators.

    PubMed

    Tomazett, Patrícia Kott; Castro, Nadya da Silva; Lenzi, Henrique Leonel; de Almeida Soares, Célia Maria; Pereira, Maristela

    2011-01-01

    In its attempt to survive, the fungal cell can change the cell wall composition and/or structure in response to environmental stress. The molecules involved in these compensatory mechanisms are a possible target for the development of effective antifungal agents. In the thermodimorphic fungus Paracoccidioides brasiliensis Pb01, the main polymers that compose the cell wall are chitin and glucans. These polymers form a primary barrier that is responsible for the structural integrity and formation of the cell wall. In this study the behaviour of P. brasiliensis was evaluated under incubation with cell wall stressor agents such as Calcofluor White (CFW), Congo Red (CR), Sodium Dodecyl Sulphate (SDS), NaCl, KCl, and Sorbitol. Use of concentrations at which the fungus is visually sensitive to those agents helped to explain some of the adaptive mechanisms used by P. brasiliensis in response to cell wall stress. Our results show that 1,3-β-D-glucan synthase (PbFKS1), glucosamine-6-phosphate synthase (PbGFA1) and β-1,3-glucanosyltransferase (PbGEL3)as well as 1,3-β-D-glucan and N-acetylglucosamine (GlcNAc) residues in the cell wall are involved in compensatory mechanisms against cell wall damage. PMID:21215956

  3. 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. PMID:26756186

  4. 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

  5. Morphometry, bite-force, and paleobiology of the late miocene caiman Purussaurus brasiliensis.

    PubMed

    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

  6. The sialotranscriptome of the blood-sucking bug Triatoma brasiliensis (Hemiptera, Triatominae)

    PubMed Central

    Santos, Adriana; Ribeiro, José Marcos C.; Lehane, Michael J.; Gontijo, Nelder Figueiredo; Veloso, Artur Botelho; Sant'Anna, Mauricio R.V.; Araujo, Ricardo Nascimento; Grisard, Edmundo C.; Pereira, Marcos Horácio

    2007-01-01

    Triatoma brasiliensis is the most important autochthon vector of Trypanosoma cruzi in Brazil, where it is widely distributed in the semiarid areas of the Northeast. In order to advance the knowledge of the salivary biomolecules of Triatominae, a salivary gland cDNA library of T. brasiliensis was mass sequenced and analyzed. Polypeptides were sequenced by HPLC/Edman degradation experiments. 1,712 cDNA sequences were obtained and grouped in 786 clusters. The housekeeping category had 24.4% and 17.8% of the clusters and sequences, respectively. The putatively secreted category contained 47.1% of the clusters and 68.2% of the sequences. Finally, 28.5% of the clusters, containing 14% of all sequences, were classified as unknown. The sialoma of T. brasiliensis showed a high amount and great variety of different lipocalins (93.8% of secreted proteins). Remarkably, a great number of serine proteases that were not observed in previous blood-sucking sialotranscriptomes were found. Nine Kazal peptides were identified, among them one with high homology to the tabanid vasodilator vasotab, suggesting that the Triatoma vasodilator could be a Kazal protein. PMID:17550826

  7. 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. PMID:26712719

  8. Lack of Galectin-3 Drives Response to Paracoccidioides brasiliensis toward a Th2-Biased Immunity

    PubMed Central

    Ruas, Luciana Pereira; Bernardes, Emerson Soares; Fermino, Marise Lopes; de Oliveira, Leandro Licursi; Hsu, Daniel K.; Liu, Fu-Tong; Chammas, Roger; Roque-Barreira, Maria-Cristina

    2009-01-01

    There is recent evidence that galectin-3 participates in immunity to infections, mostly by tuning cytokine production. We studied the balance of Th1/Th2 responses to P. brasiliensis experimental infection in the absence of galectin-3. The intermediate resistance to the fungal infection presented by C57BL/6 mice, associated with the development of a mixed type of immunity, was replaced with susceptibility to infection and a Th2-polarized immune response, in galectin-3-deficient (gal3−/−) mice. Such a response was associated with defective inflammatory and delayed type hypersensitivity (DTH) reactions, high IL-4 and GATA-3 expression and low nitric oxide production in the organs of infected animals. Gal3−/− macrophages exhibited higher TLR2 transcript levels and IL-10 production compared to wild-type macrophages after stimulation with P. brasiliensis antigens. We hypothesize that, during an in vivo P. brasiliensis infection, galectin-3 exerts its tuning role on immunity by interfering with the generation of regulatory macrophages, thus hindering the consequent Th2-polarized type of response. PMID:19229338

  9. Participation of dectin-1 receptor on NETs release against Paracoccidioides brasiliensis: Role on extracellular killing.

    PubMed

    Bachiega, Tatiana Fernanda; Dias-Melicio, Luciane Alarcão; Fernandes, Reginaldo Keller; de Almeida Balderramas, Helanderson; Rodrigues, Daniela Ramos; Ximenes, Valdecir Farias; de Campos Soares, Ângela Maria Victoriano

    2016-02-01

    Paracoccidioides brasiliensis is a dimorphic fungus from the Paracoccidioides genus, which is the causative agent of paracoccidioidomycosis, a chronic, subacute or acute mycosis, with visceral and cutaneous involvement. This disease that is acquired through inhalation primarily attacks the lungs but, can spread to other organs. Phagocytic cells as neutrophils play an important role during innate immune response against this fungus, but studies on antifungal activities of these cells are scarce. In addition to their ability to eliminate pathogens by phagocytosis and antimicrobial secretions, neutrophils can trap and kill microorganisms by release of extracellular structures composed by DNA and antimicrobial proteins, called neutrophil extracellular traps (NETs). Here, we provide evidence that P. brasiliensis virulent strain (P. brasiliensis 18) induces NETs release. These structures were well evidenced by scanning electron microscopy, and specific NETs compounds such as histone, elastase and DNA were shown by confocal microscopy. In addition, we have shown that dectin-1 receptor is the main PRR to which fungus binds to induce NETS release. Fungi were ensnared by NETs, denoting the role of these structures in confining the fungus, avoiding dissemination. NETs were also shown to be involved in fungus killing, since fungicidal activity detected before and mainly after neutrophils activation with TNF-α, IFN-γ and GM-CSF was significantly inhibited by cocultures treatment with DNAse. PMID:26416210

  10. Control of Linepithema micans (Hymenoptera: Formicidae) and Eurhizococcus brasiliensis (Hemiptera: Margarodidae) in Vineyards Using Toxic Baits.

    PubMed

    Nondillo, Aline; Andzeiewski, Simone; Bello Fialho, Flávio; Bueno, Odair Correa; Botton, Marcos

    2016-08-01

    Linepithema micans (Forel) (Hymenoptera: Formicidae) is the main ant species responsible for dispersal of Eurhizococcus brasiliensis (Wille) (Hemiptera: Margarodidae), a root scale that damages grapevines in southern Brazil. The effects of different formulations of toxic baits based on boric acid and hydramethylnon to control L. micans and E. brasiliensis were evaluated. Toxic baits with boric acid (1.0%) mixed in different concentrations of inverted sugar (20%, 30%, and 40%), and hydramethylnon, mixed with sardines (paste), cassava flour and peanut, brown sugar (sucrose), or sardine oil-based gel, were evaluated in a greenhouse and in the field. In the greenhouse experiment, the number of foraging ants was significantly reduced in the pots where the hydramethylnon in sardine paste (Solid S), sardine oil-brown sugar-based gel (GEL SAM), and peanut oil-brown-sugar gel (GEL AM) formulations were applied. The GEL SAM toxic bait effectively reduced the infestation of L. micans, and could be used for indirect control of E. brasiliensis on young grapevines. PMID:27329621

  11. 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

  12. Nocardia brasiliensis cell wall lipids modulate macrophage and dendritic responses that favor development of experimental actinomycetoma in BALB/c mice.

    PubMed

    Trevino-Villarreal, J Humberto; Vera-Cabrera, Lucio; Valero-Guillén, Pedro L; Salinas-Carmona, Mario C

    2012-10-01

    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

  13. 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

  14. 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

  15. 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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  16. Oenothein B inhibits the expression of PbFKS1 transcript and induces morphological changes in Paracoccidioides brasiliensis.

    PubMed

    Santos, Glaciane D; Ferri, Pedro H; Santos, Suzana C; Bao, Sônia N; Soares, Célia M A; Pereira, Maristela

    2007-11-01

    The fungus Paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis (PCM), the most prevalent human systemic mycosis in Latin America. Drug toxicity and the appearance of resistant strains have created the need to search for new therapeutic approaches. Plants with reputed antimicrobial properties represent a rich screening source of potential antifungal compounds. In this work, the growth of P. brasiliensis yeast cells was evaluated in the presence of oenothein B extracted from Eugenia uniflora. The oenothein B dosage that most effectively inhibited the development (74%) of P. brasiliensis yeast cells in vitro was 500 microg/ml. To verify if oenothein B interferes with cell morphology, we observed oenothein B-treated yeast cells by electron microscopy. The micrographs showed characteristic cell changes noted with glucan synthesis inhibition, including squashing, rough surface, cell wall rupture and cell membrane recess. The expression of P. brasiliensis genes was evaluated in order to investigate the action of oenothein B. Here we report that oenothein B inhibits 1,3-beta-glucan synthase (PbFKS1) transcript accumulation. The results indicate that oenothein B interferes with the cell morphology of P. brasiliensis, probably by inhibiting the transcription of 1,3-beta-glucan synthase gene, which is involved in the cell wall synthesis. PMID:18033615

  17. Type 3 muscarinic receptors contribute to intestinal mucosal homeostasis and clearance of Nippostrongylus brasiliensis through induction of TH2 cytokines.

    PubMed

    McLean, Leon P; Smith, Allen; Cheung, Lumei; Urban, Joseph F; Sun, Rex; Grinchuk, Viktoriya; Desai, Neemesh; Zhao, Aiping; Raufman, Jean-Pierre; Shea-Donohue, Terez

    2016-07-01

    Despite increased appreciation for the role of nicotinic receptors in the modulation of and response to inflammation, the contribution of muscarinic receptors to mucosal homeostasis, clearance of enteric pathogens, and modulation of immune cell function remains relatively undefined. Uninfected and Nippostrongylus brasiliensis-infected wild-type and type 3 muscarinic receptor (M3R)-deficient (Chrm3(-/-)) mice were studied to determine the contribution of M3R to mucosal homeostasis as well as host defense against the TH2-eliciting enteric nematode N. brasiliensis Intestinal permeability and expression of TH1/TH17 cytokines were increased in uninfected Chrm3(-/-) small intestine. Notably, in Chrm3(-/-) mice infected with N. brasiliensis, small intestinal upregulation of TH2 cytokines was attenuated and nematode clearance was delayed. In Chrm3(-/-) mice, TH2-dependent changes in small intestinal function including smooth muscle hypercontractility, increased epithelial permeability, decreased epithelial secretion and absorption, and goblet cell expansion were absent despite N. brasiliensis infection. These findings identify an important role for M3R in host defense and clearance of N. brasiliensis, and support the expanding role of cholinergic muscarinic receptors in maintaining mucosal homeostasis. PMID:27173511

  18. 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. PMID:26870028

  19. Antibodies Against Glycolipids Enhance Antifungal Activity of Macrophages and Reduce Fungal Burden After Infection with Paracoccidioides brasiliensis

    PubMed Central

    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. PMID:26870028

  20. 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

  1. 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

  2. Detection of Melanin-Like Pigments in the Dimorphic Fungal Pathogen Paracoccidioides brasiliensis In Vitro and during Infection

    PubMed Central

    Gómez, Beatriz L.; Nosanchuk, Joshua D.; Díez, Soraya; Youngchim, Sirida; Aisen, Philip; Cano, Luz E.; Restrepo, Angela; Casadevall, Arturo; Hamilton, Andrew J.

    2001-01-01

    Melanins are implicated in the pathogenesis of several human diseases, including some microbial infections. In this study, we analyzed whether the conidia and the yeasts of the thermally dimorphic fungal pathogen Paracoccidioides brasiliensis produce melanin or melanin-like compounds in vitro and during infection. Growth of P. brasiliensis mycelia on water agar alone produced pigmented conidia, and growth of yeasts in minimal medium with l-3,4-dihydroxyphenylalanine (l-DOPA) produced pigmented cells. Digestion of the pigmented conidia and yeasts with proteolytic enzymes, denaturant, and hot concentrated acid yielded dark particles that were the same size and shape as their propagules. Immunofluorescence analysis demonstrated reactivity of a melanin-binding monoclonal antibody (MAb) with the pigmented conidia, yeasts, and particles. Electron spin resonance spectroscopy identified the yeast-derived particles produced in vitro when P. brasiliensis was grown in l-DOPA medium as a melanin-like compound. Nonreducing polyacrylamide gel electrophoresis of cytoplasmic yeast extract revealed a protein that catalyzed melanin synthesis from l-DOPA. The melanin binding MAb reacted with yeast cells in tissue from mice infected with P. brasiliensis. Finally digestion of infected tissue liberated particles reactive to the melanin binding MAb that had the typical morphology of P. brasiliensis yeasts. These data strongly suggest that P. brasiliensis propagules, both conidia and yeast cells, can produce melanin or melanin-like compounds in vitro and in vivo. Based on what is known about the function of melanin in the virulence of other fungi, this pigment may play a role in the pathogenesis of paracoccidioidomycosis. PMID:11500453

  3. A chitinolytic endochitinase and β-N-acetylglucosaminidase-based system from Hevea latex in generating N-acetylglucosamine from chitin.

    PubMed

    Sukprasirt, Pannawich; Wititsuwannakul, Rapepun

    2014-08-01

    An endochitinase and β-N-acetylglucosaminidase (NAGase) were purified and characterised from fresh rubber latex serum. These enzymes were used in a total enzyme-based system to produce pure N-acetylglucosamine (NAG) from chitin. The N-terminal amino acid sequences of both purified endochitinase (KEESRRRRHR) and NAGase (AAVDSDTLEI) lacked homology with other known chitinases, including hevamine from rubber latex lutoids. The apparent kinetic parameters, Km and Vmax, for the endochitinase using 4-MU-β-(NAG)3 as a substrate were 99.73 μM and 29.49 pkat mg(-1), respectively. For NAGase, using 4-MU-β-NAG as a substrate, the corresponding Km and Vmax values were 20.4 μM and 25.82 pkat mg(-1). When an enzyme incubation mixture containing a 1:1 (pkat/pkat) activity mixed ratio of endochitinase: NAGase was employed, the maximum yield of N-acetylglucosamine (NAG) obtained was 98% from β-chitin and 20% from α-chitin. These yields were obtained after 4 days of hydrolysis of equal amounts of β-chitin and α-chitin in the mixture. Thus, β-chitin was the preferred substrate compared to α-chitin by a ratio of nearly five to one. Mass spectroscopic analysis, using electrospray ionisation mass spectrometry (ESI-MS), of the product obtained from β-chitin after digestion (for 24h) depicted one distinct major molecular ion peak m/z 260.1, a small minor ion peak m/z 481.2, a potassium adduct of NAG and a potassium adduct of two NAG molecules. Furthermore, experiments to establish the commercial production of NAG using crude enzymes of Hevea latex serum are currently in progress. PMID:24833032

  4. 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. PMID:25055102

  5. A conserved dimorphism-regulating histidine kinase controls the dimorphic switching in Paracoccidioides brasiliensis.

    PubMed

    Chaves, Alison F A; Navarro, Marina V; Castilho, Daniele G; Calado, Juliana C P; Conceição, Palloma M; Batista, Wagner L

    2016-08-01

    Paracoccidioides brasiliensis and P. lutzii, thermally dimorphic fungi, are the causative agents of paracoccidioidomycosis (PCM). Paracoccidioides infection occurs when conidia or mycelium fragments are inhaled by the host, which causes the Paracoccidioides cells to transition to the yeast form. The development of disease requires conidia inside the host alveoli to differentiate into yeast cells in a temperature-dependent manner. We describe the presence of a two-component signal transduction system in P. brasiliensis, which we investigated by expression analysis of a hypothetical protein gene (PADG_07579) that showed high similarity with the dimorphism-regulating histidine kinase (DRK1) gene of Blastomyces dermatitidis and Histoplasma capsulatum This gene was sensitive to environmental redox changes, which was demonstrated by a dose-dependent decrease in transcript levels after peroxide stimulation and a subtler decrease in transcript levels after NO stimulation. Furthermore, the higher PbDRK1 levels after treatment with increasing NaCl concentrations suggest that this histidine kinase can play a role as osmosensing. In the mycelium-yeast (M→Y) transition, PbDRK1 mRNA expression increased 14-fold after 24 h incubation at 37°C, consistent with similar observations in other virulent fungi. These results demonstrate that the PbDRK1 gene is differentially expressed during the dimorphic M→Y transition. Finally, when P. brasiliensis mycelium cells were exposed to a histidine kinase inhibitor and incubated at 37°C, there was a delay in the dimorphic M→Y transition, suggesting that histidine kinases could be targets of interest for PCM therapy. PMID:27268997

  6. In Vivo Activity of the Benzothiazinones PBTZ169 and BTZ043 against Nocardia brasiliensis

    PubMed Central

    González-Martínez, Norma Alejandra; Lozano-Garza, Hector Gerardo; Castro-Garza, Jorge; De Osio-Cortez, Alexandra; Vargas-Villarreal, Javier; Cavazos-Rocha, Norma; Ocampo-Candiani, Jorge; Makarov, Vadim; Cole, Stewart T.; Vera-Cabrera, Lucio

    2015-01-01

    Background Mycetoma is a neglected, chronic, and deforming infectious disease caused by fungi and actinomycetes. In Mexico, N. brasiliensis is the predominant etiologic agent. Therapeutic alternatives are necessary because the current drug regimens have several disadvantages. Benzothiazinones (BTZ) are a new class of candidate drugs that inhibit decaprenyl-phosphoribose-epimerase (DprE1), an essential enzyme involved in the cell wall biosynthesis of Corynebacterineae. Methodology/Principal findings In this study, the in vitro activity of the next generation BTZ, PBTZ169, was tested against thirty Nocardia brasiliensis isolates. The MIC50 and MIC90 values for PBTZ169 were 0.0075 and 0.03 μg/mL, respectively. Because Nocardia is a potential intracellular bacterium, a THP-1 macrophage monolayer was infected with N. brasiliensis HUJEG-1 and then treated with PBTZ169, resulting in a decrease in the number of colony-forming units (CFUs) at a concentration of 0.25X the in vitro value. The in vivo activity was evaluated after infecting female BALB/c mice in the right hind food-pad. After 6 weeks, treatment was initiated with PBTZ169 and its activity was compared with the first generation compound, BTZ043. Both BTZ compounds were administered at 100 mg/kg twice daily by gavage, and sulfamethoxazole/trimethoprim (SXT), at 100 mg/kg sulfamethoxazole, was used as a positive control. After 22 weeks of therapy, only PBTZ169 and SXT displayed statistically significant activity. Conclusion These results indicate that DprE1 inhibitors may be useful for treating infections of Nocardia and may therefore be active against other actinomycetoma agents. We must test combinations of these compounds with other antimicrobial agents, such as linezolid, tedizolid or SXT, that have good to excellent in vivo activity, as well as new DprE1 inhibitors that can achieve higher plasma levels. PMID:26474057

  7. 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. PMID:25520205

  8. Notes on the reproductive biology of the Brazilian electric ray Narcine brasiliensis (Elasmobranchii: Narcinidae).

    PubMed

    Rolim, F A; Rotundo, M M; Vaske-Júnior, T

    2016-07-01

    This study provides information on the reproductive biology of Narcine brasiliensis based on 105 individuals (72 females and 33 males) sampled in São Paulo State, Brazil. The total length at maturity for females was 318·9 mm and for males was 279·8 mm; pregnant females were observed only during summer and autumn. The peak of the gonado-somatic index for females and condition factor for males in the spring suggest a preparation for pregnancy and a mating period during this season. The capture of immature individuals indicates a need for management of the species in this region. PMID:26377171

  9. Morphological Transition of Paracoccidioides brasiliensis Conidia to Yeast Cells: In Vivo Inhibition in Females

    PubMed Central

    Aristizabal, Beatriz H.; Clemons, Karl V.; Stevens, David A.; Restrepo, Angela

    1998-01-01

    Clinical paracoccidioidomycosis is 13 times more common in men than in women. Estrogen inhibits the transition of mycelia or conidia (the saprophytic form of Paracoccidoides brasiliensis) to yeasts (the parasitic form) in vitro. Here, we show that, in male mice that were infected intranasally (mimicking natural infection) the transition of conidia in bronchoalveolar lavage fluids to intermediate forms and yeasts occurred over 24 to 96 h; CFU and yeasts (shown by histopathology) increased subsequently. In females, transition did not occur and infection cleared. These events in vivo are consistent with epidemiological and in vitro observations, suggesting that female hormones block transition and are responsible for resistance. PMID:9784579

  10. Data in support of quantitative proteomics to identify potential virulence regulators in Paracoccidioides brasiliensis isolates

    PubMed Central

    Tashima, Alexandre Keiji; Castilho, Daniele Gonçalves; Chaves, Alison Felipe Alencar; Xander, Patricia; Zelanis, André; Batista, Wagner Luiz

    2015-01-01

    Paracoccidioides genus are the etiologic agents of paracoccidioidomycosis (PCM), a systemic mycosis endemic in Latin America. Few virulence factors have been identified in these fungi. This paper describes support data from the quantitative proteomics of Paracoccidioides brasiliensis attenuated and virulent isolates [1]. The protein compositions of two isolates of the Pb18 strain showing distinct infection profiles were quantitatively assessed by stable isotopic dimethyl labeling and proteomic analysis. The mass spectrometry and the analysis dataset have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with identifier PXD000804. PMID:26501084