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Sample records for acidithiobacillus ferrooxidans atcc

  1. Cloning, expression and bioinformatics analysis of ATP sulfurylase from Acidithiobacillus ferrooxidans ATCC 23270 in Escherichia coli

    PubMed Central

    Jaramillo, Michael L; Abanto, Michel; Quispe, Ruth L; Calderón, Julio; del Valle, Luís J; Talledo, Miguel; Ramírez, Pablo

    2012-01-01

    Molecular studies of enzymes involved in sulfite oxidation in Acidithiobacillus ferrooxidans have not yet been developed, especially in the ATP sulfurylase (ATPS) of these acidophilus tiobacilli that have importance in biomining. This enzyme synthesizes ATP and sulfate from adenosine phosphosulfate (APS) and pyrophosphate (PPi), final stage of the sulfite oxidation by these organisms in order to obtain energy. The atpS gene (1674 bp) encoding the ATPS from Acidithiobacillus ferrooxidans ATCC 23270 was amplified using PCR, cloned in the pET101-TOPO plasmid, sequenced and expressed in Escherichia coli obtaining a 63.5 kDa ATPS recombinant protein according to SDS-PAGE analysis. The bioinformatics and phylogenetic analyses determined that the ATPS from A. ferrooxidans presents ATP sulfurylase (ATS) and APS kinase (ASK) domains similar to ATPS of Aquifex aeolicus, probably of a more ancestral origin. Enzyme activity towards ATP formation was determined by quantification of ATP formed from E. coli cell extracts, using a bioluminescence assay based on light emission by the luciferase enzyme. Our results demonstrate that the recombinant ATP sulfurylase from A. ferrooxidans presents an enzymatic activity for the formation of ATP and sulfate, and possibly is a bifunctional enzyme due to its high homology to the ASK domain from A. aeolicus and true kinases. PMID:23055613

  2. Cloning, expression and bioinformatics analysis of ATP sulfurylase from Acidithiobacillus ferrooxidans ATCC 23270 in Escherichia coli.

    PubMed

    Jaramillo, Michael L; Abanto, Michel; Quispe, Ruth L; Calderón, Julio; Del Valle, Luís J; Talledo, Miguel; Ramírez, Pablo

    2012-01-01

    Molecular studies of enzymes involved in sulfite oxidation in Acidithiobacillus ferrooxidans have not yet been developed, especially in the ATP sulfurylase (ATPS) of these acidophilus tiobacilli that have importance in biomining. This enzyme synthesizes ATP and sulfate from adenosine phosphosulfate (APS) and pyrophosphate (PPi), final stage of the sulfite oxidation by these organisms in order to obtain energy. The atpS gene (1674 bp) encoding the ATPS from Acidithiobacillus ferrooxidans ATCC 23270 was amplified using PCR, cloned in the pET101-TOPO plasmid, sequenced and expressed in Escherichia coli obtaining a 63.5 kDa ATPS recombinant protein according to SDS-PAGE analysis. The bioinformatics and phylogenetic analyses determined that the ATPS from A. ferrooxidans presents ATP sulfurylase (ATS) and APS kinase (ASK) domains similar to ATPS of Aquifex aeolicus, probably of a more ancestral origin. Enzyme activity towards ATP formation was determined by quantification of ATP formed from E. coli cell extracts, using a bioluminescence assay based on light emission by the luciferase enzyme. Our results demonstrate that the recombinant ATP sulfurylase from A. ferrooxidans presents an enzymatic activity for the formation of ATP and sulfate, and possibly is a bifunctional enzyme due to its high homology to the ASK domain from A. aeolicus and true kinases. PMID:23055613

  3. A genomic island provides Acidithiobacillus ferrooxidans ATCC 53993 additional copper resistance: a possible competitive advantage.

    PubMed

    Orellana, Luis H; Jerez, Carlos A

    2011-11-01

    There is great interest in understanding how extremophilic biomining bacteria adapt to exceptionally high copper concentrations in their environment. Acidithiobacillus ferrooxidans ATCC 53993 genome possesses the same copper resistance determinants as strain ATCC 23270. However, the former strain contains in its genome a 160-kb genomic island (GI), which is absent in ATCC 23270. This GI contains, amongst other genes, several genes coding for an additional putative copper ATPase and a Cus system. A. ferrooxidans ATCC 53993 showed a much higher resistance to CuSO(4) (>100 mM) than that of strain ATCC 23270 (<25 mM). When a similar number of bacteria from each strain were mixed and allowed to grow in the absence of copper, their respective final numbers remained approximately equal. However, in the presence of copper, there was a clear overgrowth of strain ATCC 53993 compared to ATCC 23270. This behavior is most likely explained by the presence of the additional copper-resistance genes in the GI of strain ATCC 53993. As determined by qRT-PCR, it was demonstrated that these genes are upregulated when A. ferrooxidans ATCC 53993 is grown in the presence of copper and were shown to be functional when expressed in copper-sensitive Escherichia coli mutants. Thus, the reason for resistance to copper of two strains of the same acidophilic microorganism could be determined by slight differences in their genomes, which may not only lead to changes in their capacities to adapt to their environment, but may also help to select the more fit microorganisms for industrial biomining operations. PMID:21789491

  4. Response to copper of Acidithiobacillus ferrooxidans ATCC 23270 grown in elemental sulfur.

    PubMed

    Almárcegui, Rodrigo J; Navarro, Claudio A; Paradela, Alberto; Albar, Juan Pablo; von Bernath, Diego; Jerez, Carlos A

    2014-11-01

    The response of Acidithiobacillus ferrooxidans ATCC 23270 to copper was analyzed in sulfur-grown cells by using quantitative proteomics. Forty-seven proteins showed altered levels in cells grown in the presence of 50 mM copper sulfate. Of these proteins, 24 were up-regulated and 23 down-regulated. As seen before in ferrous iron-grown cells, there was a notorious up-regulation of RND-type Cus systems and different RND-type efflux pumps, indicating that these proteins are very important in copper resistance. Copper also triggered the down-regulation of the major outer membrane porin of A. ferrooxidans in sulfur-grown bacteria, suggesting they respond to the metal by decreasing the influx of cations into the cell. On the contrary, copper in sulfur-grown cells caused an overexpression of putative TadA and TadB proteins known to be essential for biofilm formation in bacteria. Surprisingly, sulfur-grown microorganisms showed increased levels of proteins related with energy generation (rus and petII operons) in the presence of copper. Although rus operon is overexpressed mainly in cells grown in ferrous iron, the up-regulation of rusticyanin in sulfur indicates a possible role for this protein in copper resistance as well. Finally, copper response in A. ferrooxidans appears to be influenced by the substrate being oxidized by the microorganism. PMID:25041950

  5. Comparative genomic analysis of Acidithiobacillus ferrooxidans strains using the A. ferrooxidans ATCC 23270 whole-genome oligonucleotide microarray.

    PubMed

    Luo, Hailang; Shen, Li; Yin, Huaqun; Li, Qian; Chen, Qijiong; Luo, Yanjie; Liao, Liqin; Qiu, Guanzhou; Liu, Xueduan

    2009-05-01

    Acidithiobacillus ferrooxidans is an important microorganism used in biomining operations for metal recovery. Whole-genomic diversity analysis based on the oligonucleotide microarray was used to analyze the gene content of 12 strains of A. ferrooxidans purified from various mining areas in China. Among the 3100 open reading frames (ORFs) on the slides, 1235 ORFs were absent in at least 1 strain of bacteria and 1385 ORFs were conserved in all strains. The hybridization results showed that these strains were highly diverse from a genomic perspective. The hybridization results of 4 major functional gene categories, namely electron transport, carbon metabolism, extracellular polysaccharides, and detoxification, were analyzed. Based on the hybridization signals obtained, a phylogenetic tree was built to analyze the evolution of the 12 tested strains, which indicated that the geographic distribution was the main factor influencing the strain diversity of these strains. Based on the hybridization signals of genes associated with bioleaching, another phylogenetic tree showed an evolutionary relationship from which the co-relation between the clustering of specific genes and geochemistry could be observed. The results revealed that the main factor was geochemistry, among which the following 6 factors were the most important: pH, Mg, Cu, S, Fe, and Al. PMID:19483787

  6. Periplasmic Proteins of the Extremophile Acidithiobacillus ferrooxidans

    PubMed Central

    Chi, An; Valenzuela, Lissette; Beard, Simon; Mackey, Aaron J.; Shabanowitz, Jeffrey; Hunt, Donald F.; Jerez, Carlos A.

    2015-01-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic acidophile capable of obtaining energy by oxidizing ferrous iron or sulfur compounds such as metal sulfides. Some of the proteins involved in these oxidations have been described as forming part of the periplasm of this extremophile. The detailed study of the periplasmic components constitutes an important area to understand the physiology and environmental interactions of microorganisms. Proteomics analysis of the periplasmic fraction of A. ferrooxidans ATCC 23270 was performed by using high resolution linear ion trap-FT MS. We identified a total of 131 proteins in the periplasm of the microorganism grown in thiosulfate. When possible, functional categories were assigned to the proteins: 13.8% were transport and binding proteins, 14.6% were several kinds of cell envelope proteins, 10.8% were involved in energy metabolism, 10% were related to protein fate and folding, 10% were proteins with unknown functions, and 26.1% were proteins without homologues in databases. These last proteins are most likely characteristic of A. ferrooxidans and may have important roles yet to be assigned. The majority of the periplasmic proteins from A. ferrooxidans were very basic compared with those of neutrophilic microorganisms such as Escherichia coli, suggesting a special adaptation of the chemolithoautotrophic bacterium to its very acidic environment. The high throughput proteomics approach used here not only helps to understand the physiology of this extreme acidophile but also offers an important contribution to the functional annotation for the available genomes of biomining microorganisms such as A. ferrooxidans for which no efficient genetic systems are available to disrupt genes by procedures such as homologous recombination. PMID:17911085

  7. Genome wide identification of Acidithiobacillus ferrooxidans (ATCC 23270) transcription factors and comparative analysis of ArsR and MerR metal regulators.

    PubMed

    Hödar, Christian; Moreno, Pablo; di Genova, Alex; Latorre, Mauricio; Reyes-Jara, Angélica; Maass, Alejandro; González, Mauricio; Cambiazo, Verónica

    2012-02-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic acidophilic bacterium that obtains its energy from the oxidation of ferrous iron, elemental sulfur, or reduced sulfur minerals. This capability makes it of great industrial importance due to its applications in biomining. During the industrial processes, A. ferrooxidans survives to stressing circumstances in its environment, such as an extremely acidic pH and high concentration of transition metals. In order to gain insight into the organization of A. ferrooxidans regulatory networks and to provide a framework for further studies in bacterial growth under extreme conditions, we applied a genome-wide annotation procedure to identify 87 A. ferrooxidans transcription factors. We classified them into 19 families that were conserved among diverse prokaryotic phyla. Our annotation procedure revealed that A. ferrooxidans genome contains several members of the ArsR and MerR families, which are involved in metal resistance and detoxification. Analysis of their sequences revealed known and potentially new mechanism to coordinate gene-expression in response to metal availability. A. ferrooxidans inhabit some of the most metal-rich environments known, thus transcription factors identified here seem to be good candidates for functional studies in order to determine their physiological roles and to place them into A. ferrooxidans transcriptional regulatory networks. PMID:21830017

  8. Transcriptional and functional studies of a Cd(II)/Pb(II)-responsive transcriptional regulator(CmtR) from Acidithiobacillus ferrooxidans ATCC 23270.

    PubMed

    Zheng, Chunli; Li, Yanjun; Nie, Li; Qian, Lin; Cai, Lu; Liu, Jianshe

    2012-08-01

    The acidophilic Acidithiobacillus ferrooxidans can resist exceptionally high cadmium (Cd) concentrations. This property is important for its use in biomining processes, where Cd and other metal levels range usually between 15 and 100 mM. To learn about the mechanisms that allow A. ferrooxidans cells to survive in this environment, a bioinformatic search of its genome showed the presence of that a Cd(II)/Pb(II)-responsive transcriptional regulator (CmtR) was possibly related to Cd homeostasis. The expression of the CmtR was studied by real-time reverse transcriptase PCR using A. ferrooxidans cells adapted for growth in the presence of high concentrations of Cd. The putative A. ferrooxidans Cd resistance determinant was found to be upregulated when this bacterium was exposed to Cd in the range of 15-30 mM. The CmtR from A. ferrooxidans was cloned and expressed in Escherichia coli, the soluble protein was purified by one-step affinity chromatography to apparent homogeneity. UV-Vis spectroscopic measurements showed that the reconstruction CmtR was able to bind Cd(II) forming Cd(II)-CmtR complex in vitro. The sequence alignment and molecular modeling showed that the crucial residues for CmtR binding were likely to be Cys77, Cys112, and Cys121. The results reported here strongly suggest that the high resistance of the extremophilic A. ferrooxidans to Cd including the Cd(II)/Pb(II)-responsive transcriptional regulator. PMID:22555344

  9. Cytoplasmic CopZ-Like Protein and Periplasmic Rusticyanin and AcoP Proteins as Possible Copper Resistance Determinants in Acidithiobacillus ferrooxidans ATCC 23270

    PubMed Central

    Navarro, Claudio A.; von Bernath, Diego; Martínez-Bussenius, Cristóbal; Castillo, Rodrigo A.

    2015-01-01

    Acidophilic organisms, such as Acidithiobacillus ferrooxidans, possess high-level resistance to copper and other metals. A. ferrooxidans contains canonical copper resistance determinants present in other bacteria, such as CopA ATPases and RND efflux pumps, but these components do not entirely explain its high metal tolerance. The aim of this study was to find other possible copper resistance determinants in this bacterium. Transcriptional expression of A. ferrooxidans genes coding for a cytoplasmic CopZ-like copper-binding chaperone and the periplasmic copper-binding proteins rusticyanin and AcoP, which form part of an iron-oxidizing supercomplex, was found to increase when the microorganism was grown in the presence of copper. All of these proteins conferred more resistance to copper when expressed heterologously in a copper-sensitive Escherichia coli strain. This effect was absent when site-directed-mutation mutants of these proteins with altered copper-binding sites were used in this metal sensitivity assay. These results strongly suggest that the three copper-binding proteins analyzed here are copper resistance determinants in this extremophile and contribute to the high-level metal resistance of this industrially important biomining bacterium. PMID:26637599

  10. Cytoplasmic CopZ-Like Protein and Periplasmic Rusticyanin and AcoP Proteins as Possible Copper Resistance Determinants in Acidithiobacillus ferrooxidans ATCC 23270.

    PubMed

    Navarro, Claudio A; von Bernath, Diego; Martínez-Bussenius, Cristóbal; Castillo, Rodrigo A; Jerez, Carlos A

    2016-02-01

    Acidophilic organisms, such as Acidithiobacillus ferrooxidans, possess high-level resistance to copper and other metals. A. ferrooxidans contains canonical copper resistance determinants present in other bacteria, such as CopA ATPases and RND efflux pumps, but these components do not entirely explain its high metal tolerance. The aim of this study was to find other possible copper resistance determinants in this bacterium. Transcriptional expression of A. ferrooxidans genes coding for a cytoplasmic CopZ-like copper-binding chaperone and the periplasmic copper-binding proteins rusticyanin and AcoP, which form part of an iron-oxidizing supercomplex, was found to increase when the microorganism was grown in the presence of copper. All of these proteins conferred more resistance to copper when expressed heterologously in a copper-sensitive Escherichia coli strain. This effect was absent when site-directed-mutation mutants of these proteins with altered copper-binding sites were used in this metal sensitivity assay. These results strongly suggest that the three copper-binding proteins analyzed here are copper resistance determinants in this extremophile and contribute to the high-level metal resistance of this industrially important biomining bacterium. PMID:26637599

  11. Acidithiobacillus ferrooxidans metabolism: from genome sequence to industrial applications

    PubMed Central

    Valdés, Jorge; Pedroso, Inti; Quatrini, Raquel; Dodson, Robert J; Tettelin, Herve; Blake, Robert; Eisen, Jonathan A; Holmes, David S

    2008-01-01

    Background Acidithiobacillus ferrooxidans is a major participant in consortia of microorganisms used for the industrial recovery of copper (bioleaching or biomining). It is a chemolithoautrophic, γ-proteobacterium using energy from the oxidation of iron- and sulfur-containing minerals for growth. It thrives at extremely low pH (pH 1–2) and fixes both carbon and nitrogen from the atmosphere. It solubilizes copper and other metals from rocks and plays an important role in nutrient and metal biogeochemical cycling in acid environments. The lack of a well-developed system for genetic manipulation has prevented thorough exploration of its physiology. Also, confusion has been caused by prior metabolic models constructed based upon the examination of multiple, and sometimes distantly related, strains of the microorganism. Results The genome of the type strain A. ferrooxidans ATCC 23270 was sequenced and annotated to identify general features and provide a framework for in silico metabolic reconstruction. Earlier models of iron and sulfur oxidation, biofilm formation, quorum sensing, inorganic ion uptake, and amino acid metabolism are confirmed and extended. Initial models are presented for central carbon metabolism, anaerobic metabolism (including sulfur reduction, hydrogen metabolism and nitrogen fixation), stress responses, DNA repair, and metal and toxic compound fluxes. Conclusion Bioinformatics analysis provides a valuable platform for gene discovery and functional prediction that helps explain the activity of A. ferrooxidans in industrial bioleaching and its role as a primary producer in acidic environments. An analysis of the genome of the type strain provides a coherent view of its gene content and metabolic potential. PMID:19077236

  12. Cytoplasmic membrane response to copper and nickel in Acidithiobacillus ferrooxidans.

    PubMed

    Mykytczuk, N C S; Trevors, J T; Ferroni, G D; Leduc, L G

    2011-03-20

    Metal tolerance has been found to vary among Acidithiobacillus ferrooxidans strains and this can impact the efficiency of biomining practices. To explain observed strain variability for differences in metal tolerance we examined the effects of Cu(2+) and Ni(2+) concentrations (1-200 mM) on cytoplasmic membrane properties of two A. ferrooxidans type strains (ATCC 23270 and 19859) and four strains isolated from AMD water around Sudbury, Ontario, Canada. Growth rate, membrane fluidity and phase, determined from the fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH), and fatty acid profiles indicated that three different modes of adaptation were present and could separate between strains showing moderate, or high metal tolerance from more sensitive strains. To compensate for the membrane ordering effects of the metals, significant remodelling of the membrane was used to either maintain homeoviscous adaptation in the moderately tolerant strains or to increase membrane fluidity in the sensitive strains. Shifts in the gel-to-liquid crystalline transition temperature in the moderately tolerant strains led to multiple phase transitions, increasing the potential for phase separation and compromised membrane integrity. The metal-tolerant strain however, was able to tolerate increases in membrane order without significant compensation via fatty acid composition. Our multivariate analyses show a common adaptive response which involves changes in the abundant 16:0 and 18:1 fatty acids. However, fatty acid composition and membrane properties showed no difference in response to either copper or nickel suggesting that adaptive response was non-specific and tolerance dependent. We demonstrate that strain variation can be evaluated using differences in membrane properties as intrinsic determinants of metal susceptibility. PMID:20630730

  13. Weathering of phlogopite by Bacillus cereus and Acidithiobacillus ferrooxidans.

    PubMed

    Styriaková, Iveta; Bhatti, Tariq M; Bigham, Jerry M; Styriak, Igor; Vuorinen, Antti; Tuovinen, Olli H

    2004-03-01

    The purpose of this study was to assess the weathering of finely ground phlogopite, a trioctahedral mica, by placing it in contact with heterotrophic (Bacillus cereus) and acidophilic (Acidithiobacillus ferrooxidans) cultures. X-ray diffraction analyses of the phlogopite sample before and after 24 weeks of contact in B. cereus cultures revealed a decrease in the characteristic peak intensities of phlogopite, indicating destruction of individual structural planes of the mica. No new solid phase products or interlayer structures were detected in B. cereus cultures. Acidithiobacillus ferrooxidans cultures enhanced the chemical dissolution of the mineral and formed partially weathered interlayer structures, where interlayer K was expelled and coupled with the precipitation of K-jarosite [KFe3(SO4)2(OH)6]. PMID:15105888

  14. Draft genome sequence of Acidithiobacillus ferrooxidans YQH-1

    PubMed Central

    Yan, Lei; Zhang, Shuang; Wang, Weidong; Hu, Huixin; Wang, Yanjie; Yu, Gaobo; Chen, Peng

    2015-01-01

    Acidithiobacillus ferrooxidans YQH-1 is a moderate acidophilic bacterium isolated from a river in a volcano of Northeast China. Here, we describe the draft genome of strain YQH-1, which was assembled into 123 contigs containing 3,111,222 bp with a G + C content of 58.63%. A large number of genes related to carbon dioxide fixation, dinitrogen fixation, pH tolerance, heavy metal detoxification, and oxidative stress defense were detected. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. LJBT00000000. PMID:26697394

  15. Draft genome sequence of Acidithiobacillus ferrooxidans YQH-1.

    PubMed

    Yan, Lei; Zhang, Shuang; Wang, Weidong; Hu, Huixin; Wang, Yanjie; Yu, Gaobo; Chen, Peng

    2015-12-01

    Acidithiobacillus ferrooxidans YQH-1 is a moderate acidophilic bacterium isolated from a river in a volcano of Northeast China. Here, we describe the draft genome of strain YQH-1, which was assembled into 123 contigs containing 3,111,222 bp with a G + C content of 58.63%. A large number of genes related to carbon dioxide fixation, dinitrogen fixation, pH tolerance, heavy metal detoxification, and oxidative stress defense were detected. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. LJBT00000000. PMID:26697394

  16. Periplasmic proteins of the extremophile Acidithiobacillus ferrooxidans: a high throughput proteomics analysis.

    PubMed

    Chi, An; Valenzuela, Lissette; Beard, Simon; Mackey, Aaron J; Shabanowitz, Jeffrey; Hunt, Donald F; Jerez, Carlos A

    2007-12-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic acidophile capable of obtaining energy by oxidizing ferrous iron or sulfur compounds such as metal sulfides. Some of the proteins involved in these oxidations have been described as forming part of the periplasm of this extremophile. The detailed study of the periplasmic components constitutes an important area to understand the physiology and environmental interactions of microorganisms. Proteomics analysis of the periplasmic fraction of A. ferrooxidans ATCC 23270 was performed by using high resolution linear ion trap-FT MS. We identified a total of 131 proteins in the periplasm of the microorganism grown in thiosulfate. When possible, functional categories were assigned to the proteins: 13.8% were transport and binding proteins, 14.6% were several kinds of cell envelope proteins, 10.8% were involved in energy metabolism, 10% were related to protein fate and folding, 10% were proteins with unknown functions, and 26.1% were proteins without homologues in databases. These last proteins are most likely characteristic of A. ferrooxidans and may have important roles yet to be assigned. The majority of the periplasmic proteins from A. ferrooxidans were very basic compared with those of neutrophilic microorganisms such as Escherichia coli, suggesting a special adaptation of the chemolithoautotrophic bacterium to its very acidic environment. The high throughput proteomics approach used here not only helps to understand the physiology of this extreme acidophile but also offers an important contribution to the functional annotation for the available genomes of biomining microorganisms such as A. ferrooxidans for which no efficient genetic systems are available to disrupt genes by procedures such as homologous recombination. PMID:17911085

  17. Development of a markerless gene replacement system for Acidithiobacillus ferrooxidans and construction of a pfkB mutant.

    PubMed

    Wang, Huiyan; Liu, Xiangmei; Liu, Shuangshuang; Yu, Yangyang; Lin, Jianqun; Lin, Jianqiang; Pang, Xin; Zhao, Jian

    2012-03-01

    The extremely acidophilic, chemolithoautotrophic Acidithiobacillus ferrooxidans is an important bioleaching bacterium of great value in the metallurgical industry and environmental protection. In this report, a mutagenesis system based on the homing endonuclease I-SceI was developed to produce targeted, unmarked gene deletions in the strain A. ferrooxidans ATCC 23270. A targeted phosphofructokinase (PFK) gene (pfkB) mutant of A. ferrooxidans ATCC 23270 was constructed by homologous recombination and identified by PCR with specific primers as well as Southern blot analysis. This potential pfkB gene (AFE_1807) was also characterized by expression in PFK-deficient Escherichia coli cells, and heteroexpression of the PFKB protein demonstrated that it had functional PFK activity, though it was significantly lower (about 800-fold) than that of phosphofructokinase-2 (PFK-B) expressed by the pfkB gene from E. coli K-12. The function of the potential PFKB protein in A. ferrooxidans was demonstrated by comparing the properties of the pfkB mutant with those of the wild type. The pfkB mutant strain displayed a relatively reduced growth capacity in S(0) medium (0.5% [wt/vol] elemental sulfur in 9K basal salts solution adjusted to pH 3.0 with H(2)SO(4)), but the mutation did not completely prevent A. ferrooxidans from assimilating exogenous glucose. The transcriptional analysis of some related genes in central carbohydrate metabolism in the wild-type and mutant strains with or without supplementation of glucose was carried out by quantitative reverse transcription-PCR. This report suggests that the markerless mutagenesis strategy could serve as a model for functional studies of other genes of interest from A. ferrooxidans and multiple mutations could be made in a single A. ferrooxidans strain. PMID:22210219

  18. New copper resistance determinants in the extremophile acidithiobacillus ferrooxidans: a quantitative proteomic analysis.

    PubMed

    Almárcegui, Rodrigo J; Navarro, Claudio A; Paradela, Alberto; Albar, Juan Pablo; von Bernath, Diego; Jerez, Carlos A

    2014-02-01

    Acidithiobacillus ferrooxidans is an extremophilic bacterium used in biomining processes to recover metals. The presence in A. ferrooxidans ATCC 23270 of canonical copper resistance determinants does not entirely explain the extremely high copper concentrations this microorganism is able to stand, suggesting the existence of other efficient copper resistance mechanisms. New possible copper resistance determinants were searched by using 2D-PAGE, real time PCR (qRT-PCR) and quantitative proteomics with isotope-coded protein labeling (ICPL). A total of 594 proteins were identified of which 120 had altered levels in cells grown in the presence of copper. Of this group of proteins, 76 were up-regulated and 44 down-regulated. The up-regulation of RND-type Cus systems and different RND-type efflux pumps was observed in response to copper, suggesting that these proteins may be involved in copper resistance. An overexpression of most of the genes involved in histidine synthesis and several of those annotated as encoding for cysteine production was observed in the presence of copper, suggesting a possible direct role for these metal-binding amino acids in detoxification. Furthermore, the up-regulation of putative periplasmic disulfide isomerases was also seen in the presence of copper, suggesting that they restore copper-damaged disulfide bonds to allow cell survival. Finally, the down-regulation of the major outer membrane porin and some ionic transporters was seen in A. ferrooxidans grown in the presence of copper, indicating a general decrease in the influx of the metal and other cations into the cell. Thus, A. ferrooxidans most likely uses additional copper resistance strategies in which cell envelope proteins are key components. This knowledge will not only help to understand the mechanism of copper resistance in this extreme acidophile but may help also to select the best fit members of the biomining community to attain more efficient industrial metal leaching

  19. Toxin-Antitoxin Systems in the Mobile Genome of Acidithiobacillus ferrooxidans

    PubMed Central

    Bustamante, Paula; Tello, Mario; Orellana, Omar

    2014-01-01

    Toxin-antitoxin (TA) systems are genetic modules composed of a pair of genes encoding a stable toxin and an unstable antitoxin that inhibits toxin activity. They are widespread among plasmids and chromosomes of bacteria and archaea. TA systems are known to be involved in the stabilization of plasmids but there is no consensus about the function of chromosomal TA systems. To shed light on the role of chromosomally encoded TA systems we analyzed the distribution and functionality of type II TA systems in the chromosome of two strains from Acidithiobacillus ferrooxidans (ATCC 23270 and 53993), a Gram-negative, acidophilic, environmental bacterium that participates in the bioleaching of minerals. As in other environmental microorganisms, A. ferrooxidans has a high content of TA systems (28-29) and in twenty of them the toxin is a putative ribonuclease. According to the genetic context, some of these systems are encoded near or within mobile genetic elements. Although most TA systems are shared by both strains, four of them, which are encoded in the active mobile element ICEAfe1, are exclusive to the type strain ATCC 23270. We demostrated that two TA systems from ICEAfe1 are functional in E. coli cells, since the toxins inhibit growth and the antitoxins counteract the effect of their cognate toxins. All the toxins from ICEAfe1, including a novel toxin, are RNases with different ion requirements. The data indicate that some of the chromosomally encoded TA systems are actually part of the A. ferrooxidans mobile genome and we propose that could be involved in the maintenance of these integrated mobile genetic elements. PMID:25384039

  20. Tetrathionate-Forming Thiosulfate Dehydrogenase from the Acidophilic, Chemolithoautotrophic Bacterium Acidithiobacillus ferrooxidans

    PubMed Central

    Kikumoto, Mei; Nogami, Shohei; Kanao, Tadayoshi; Takada, Jun

    2013-01-01

    Thiosulfate dehydrogenase is known to play a significant role in thiosulfate oxidation in the acidophilic, obligately chemolithoautotroph, Acidithiobacillus ferrooxidans. Enzyme activity measured using ferricyanide as the electron acceptor was detected in cell extracts of A. ferrooxidans ATCC 23270 grown on tetrathionate or sulfur, but no activity was detected in ferrous iron-grown cells. The enzyme was enriched 63-fold from cell extracts of tetrathionate-grown cells. Maximum enzyme activity (13.8 U mg−1) was observed at pH 2.5 and 70°C. The end product of the enzyme reaction was tetrathionate. The enzyme reduced neither ubiquinone nor horse heart cytochrome c, which serves as an electron acceptor. A major protein with a molecular mass of ∼25 kDa was detected in the partially purified preparation. Heme was not detected in the preparation, according to the results of spectroscopic analysis and heme staining. The open reading frame of AFE_0042 was identified by BLAST by using the N-terminal amino acid sequence of the protein. The gene was found within a region that was previously noted for sulfur metabolism-related gene clustering. The recombinant protein produced in Escherichia coli had a molecular mass of ∼25 kDa and showed thiosulfate dehydrogenase activity, with maximum enzyme activity (6.5 U mg−1) observed at pH 2.5 and 50°C. PMID:23064330

  1. Synergy between Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the Bioleaching Process of Copper.

    PubMed

    Zheng, Xuecheng; Li, Dongwei

    2016-01-01

    This study investigates the synergy of Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the bioleaching process of copper. The results showed that additional R. phaseoli could increase leaching rate and cell number of A. ferrooxidans. When the initial cell number ratio between A. ferrooxidans and R. phaseoli was 2 : 1, A. ferrooxidans attained the highest final cell number of approximately 2 × 10(8) cells/mL and the highest copper leaching rate of 29%, which is 7% higher than that in the group with A. ferrooxidans only. R. phaseoli may use metabolized polysaccharides from A. ferrooxidans, and organic acids could chelate or precipitate harmful heavy metals to reduce their damage on A. ferrooxidans and promote its growth. Organic acids could also damage the mineral lattice to increase the leaching effect. PMID:26942203

  2. Synergy between Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the Bioleaching Process of Copper

    PubMed Central

    Zheng, Xuecheng; Li, Dongwei

    2016-01-01

    This study investigates the synergy of Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the bioleaching process of copper. The results showed that additional R. phaseoli could increase leaching rate and cell number of A. ferrooxidans. When the initial cell number ratio between A. ferrooxidans and R. phaseoli was 2 : 1, A. ferrooxidans attained the highest final cell number of approximately 2 × 108 cells/mL and the highest copper leaching rate of 29%, which is 7% higher than that in the group with A. ferrooxidans only. R. phaseoli may use metabolized polysaccharides from A. ferrooxidans, and organic acids could chelate or precipitate harmful heavy metals to reduce their damage on A. ferrooxidans and promote its growth. Organic acids could also damage the mineral lattice to increase the leaching effect. PMID:26942203

  3. Extending the models for iron and sulfur oxidation in the extreme Acidophile Acidithiobacillus ferrooxidans

    PubMed Central

    2009-01-01

    Background Acidithiobacillus ferrooxidans gains energy from the oxidation of ferrous iron and various reduced inorganic sulfur compounds at very acidic pH. Although an initial model for the electron pathways involved in iron oxidation has been developed, much less is known about the sulfur oxidation in this microorganism. In addition, what has been reported for both iron and sulfur oxidation has been derived from different A. ferrooxidans strains, some of which have not been phylogenetically characterized and some have been shown to be mixed cultures. It is necessary to provide models of iron and sulfur oxidation pathways within one strain of A. ferrooxidans in order to comprehend the full metabolic potential of the pangenome of the genus. Results Bioinformatic-based metabolic reconstruction supported by microarray transcript profiling and quantitative RT-PCR analysis predicts the involvement of a number of novel genes involved in iron and sulfur oxidation in A. ferrooxidans ATCC23270. These include for iron oxidation: cup (copper oxidase-like), ctaABT (heme biogenesis and insertion), nuoI and nuoK (NADH complex subunits), sdrA1 (a NADH complex accessory protein) and atpB and atpE (ATP synthetase F0 subunits). The following new genes are predicted to be involved in reduced inorganic sulfur compounds oxidation: a gene cluster (rhd, tusA, dsrE, hdrC, hdrB, hdrA, orf2, hdrC, hdrB) encoding three sulfurtransferases and a heterodisulfide reductase complex, sat potentially encoding an ATP sulfurylase and sdrA2 (an accessory NADH complex subunit). Two different regulatory components are predicted to be involved in the regulation of alternate electron transfer pathways: 1) a gene cluster (ctaRUS) that contains a predicted iron responsive regulator of the Rrf2 family that is hypothesized to regulate cytochrome aa3 oxidase biogenesis and 2) a two component sensor-regulator of the RegB-RegA family that may respond to the redox state of the quinone pool. Conclusion

  4. Metabolomic study of Chilean biomining bacteria Acidithiobacillus ferrooxidans strain Wenelen and Acidithiobacillus thiooxidans strain Licanantay.

    PubMed

    Martínez, Patricio; Gálvez, Sebastián; Ohtsuka, Norimasa; Budinich, Marko; Cortés, María Paz; Serpell, Cristián; Nakahigashi, Kenji; Hirayama, Akiyoshi; Tomita, Masaru; Soga, Tomoyoshi; Martínez, Servet; Maass, Alejandro; Parada, Pilar

    2013-02-01

    In this study, we present the first metabolic profiles for two bioleaching bacteria using capillary electrophoresis coupled with mass spectrometry. The bacteria, Acidithiobacillus ferrooxidans strain Wenelen (DSM 16786) and Acidithiobacillus thiooxidans strain Licanantay (DSM 17318), were sampled at different growth phases and on different substrates: the former was grown with iron and sulfur, and the latter with sulfur and chalcopyrite. Metabolic profiles were scored from planktonic and sessile states. Spermidine was detected in intra- and extracellular samples for both strains, suggesting it has an important role in biofilm formation in the presence of solid substrate. The canonical pathway for spermidine synthesis seems absent as its upstream precursor, putrescine, was not present in samples. Glutathione, a catalytic activator of elemental sulfur, was identified as one of the most abundant metabolites in the intracellular space in A. thiooxidans strain Licanantay, confirming its participation in the sulfur oxidation pathway. Amino acid profiles varied according to the growth conditions and bioleaching species. Glutamic and aspartic acid were highly abundant in intra- and extracellular extracts. Both are constituents of the extracellular matrix, and have a probable role in cell detoxification. This novel metabolomic information validates previous knowledge from in silico metabolic reconstructions based on genomic sequences, and reveals important biomining functions such as biofilm formation, energy management and stress responses. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-012-0443-3) contains supplementary material, which is available to authorized users. PMID:23335869

  5. Bioleaching of two different types of chalcopyrite by Acidithiobacillus ferrooxidans

    NASA Astrophysics Data System (ADS)

    Dong, Ying-bo; Lin, Hai; Fu, Kai-bin; Xu, Xiao-fang; Zhou, Shan-shan

    2013-02-01

    Two different types of chalcopyrite (pyritic chalcopyrite and porphyry chalcopyrite) were bioleached with Acidithiobacillus ferrooxidans ATF6. The bioleaching of the pyritic chalcopyrite and porphyry chalcopyrite is quite different. The copper extraction reaches 46.96% for the pyritic chalcopyrite after 48-d leaching, but it is only 14.50% for the porphyry chalcopyrite. Proper amounts of initial ferrous ions can improve the efficiency of copper extraction for the two different types of chalcopyrite. The optimum dosage of ferrous ions for the pyritic chalcopyrite and porphyry chalcopyrite is different. The adsorption of ATF6 on the pyritic chalcopyrite and porphyry chalcopyrite was also studied in this paper. It is found that ATF6 is selectively adsorbed by the two different types of chalcopyrite; the higher adsorption onto the pyritic chalcopyrite than the porphyry chalcopyrite leads to the higher copper dissolution rate of the pyritic chalcopyrite. In addition, the zeta-potential of chalcopyrite before and after bioleaching further confirms that ATF6 is more easily adsorbed onto the pyritic chalcopyrite.

  6. Insights into the iron and sulfur energetic metabolism of Acidithiobacillus ferrooxidans by microarray transcriptome profiling

    SciTech Connect

    R. Quatrini; C. Appia-Ayme; Y. Denis; J. Ratouchniak; F. Veloso; J. Valdes; C. Lefimil; S. Silver; F. Roberto; O. Orellana; F. Denizot; E. Jedlicki; D. Holmes; V. Bonnefoy

    2006-09-01

    Acidithiobacillus ferrooxidans is a well known acidophilic, chemolithoautotrophic, Gram negative, bacterium involved in bioleaching and acid mine drainage. In aerobic conditions, it gains energy mainly from the oxidation of ferrous iron and/or reduced sulfur compounds present in ores. After initial oxidation of the substrate, electrons from ferrous iron or sulfur enter respiratory chains and are transported through several redox proteins to oxygen. However, the oxidation of ferrous iron and reduced sulfur compounds has also to provide electrons for the reduction of NAD(P) that is subsequently required for many metabolic processes including CO2 fixation. To help to unravel the enzymatic pathways and the electron transfer chains involved in these processes, a genome-wide microarray transcript profiling analysis was carried out. Oligonucleotides corresponding to approximately 3000 genes of the A. ferrooxidans type strain ATCC23270 were spotted onto glass-slides and hybridized with cDNA retrotranscribed from RNA extracted from ferrous iron and sulfur grown cells. The genes which are preferentially transcribed in ferrous iron conditions and those preferentially transcribed in sulfur conditions were analyzed. The expression of a substantial number of these genes has been validated by real-time PCR, Northern blot hybridization and/or immunodetection analysis. Our results support and extend certain models of iron and sulfur oxidation and highlight previous observations regarding the possible presence of alternate electron pathways. Our findings also suggest ways in which iron and sulfur oxidation may be co-ordinately regulated. An accompanying paper (Appia-Ayme et al.) describes results pertaining to other metabolic functions.

  7. ICE Afe 1, an actively excising genetic element from the biomining bacterium Acidithiobacillus ferrooxidans.

    PubMed

    Bustamante, Paula; Covarrubias, Paulo C; Levicán, Gloria; Katz, Assaf; Tapia, Pablo; Holmes, David; Quatrini, Raquel; Orellana, Omar

    2012-01-01

    Integrative conjugative elements (ICEs) are self-transferred mobile genetic elements that contribute to horizontal gene transfer. An ICE (ICEAfe1) was identified in the genome of Acidithiobacillus ferrooxidans ATCC 23270. Excision of the element and expression of relevant genes under normal and DNA-damaging growth conditions was analyzed. Bioinformatic tools and DNA amplification methods were used to identify and to assess the excision and expression of genes related to the mobility of the element. Both basal and mitomycin C-inducible excision as well as expression and induction of the genes for integration/excision are demonstrated, suggesting that ICEAfe1 is an actively excising SOS-regulated mobile genetic element. The presence of a complete set of genes encoding self-transfer functions that are induced in response to DNA damage caused by mitomycin C additionally suggests that this element is capable of conjugative transfer to suitable recipient strains. Transfer of ICEAfe1 may provide selective advantages to other acidophiles in this ecological niche through dissemination of gene clusters expressing transfer RNAs, CRISPRs, and exopolysaccharide biosynthesis enzymes, probably by modification of translation efficiency, resistance to bacteriophage infection and biofilm formation, respectively. These data open novel avenues of research on conjugative transformation of biotechnologically relevant microorganisms recalcitrant to genetic manipulation. PMID:23486178

  8. Nucleotide sequence of a small cryptic plasmid from Acidithiobacillus ferrooxidans strain A-6

    SciTech Connect

    F. Roberto

    2003-10-01

    A 2.1 kb cryptic plasmid from Acidithiobacillus ferrooxidans strain A-6 was isolated and cloned into the E. coli vector plasmid, pUC128. The cloned plasmid was mapped by restriction enzyme fragment analysis and subsequently sequenced. At this time over half the plasmid sequence has been determined and compared to sequences in the GenBank nucleotide and protein sequence databases. Much of the plasmid remains cryptic, but substantial nucleotide and protein sequence similarities have been observed to the putative replication protein, RepA, of the small cryptic plasmids pAYS and pAYL found in the ammonia-oxidizing Nitrosomonas sp. Strain ENI-11. These results suggest an entirely new class of plasmid is maintained in at least one strain of Acidithiobacillus ferrooxidans and other acidophilic bacteria, and raises interesting questions about the origin of this plasmid in acidic environments.

  9. Insights into the relation between adhesion force and chalcopyrite-bioleaching by Acidithiobacillus ferrooxidans.

    PubMed

    Zhu, Jianyu; Wang, Qianfen; Zhou, Shuang; Li, Qian; Gan, Min; Jiang, Hao; Qin, Wenqing; Liu, Xueduan; Hu, Yuehua; Qiu, Guanzhou

    2015-02-01

    This paper presents a study on the relation between bacterial adhesion force and bioleaching rate of chalcopyrite, which sheds light on the influence of interfacial interaction on bioleaching behavior. In our research, Acidithiobacillus ferrooxidans (A. ferrooxidans) were adapted to grow with FeSO4 · 7H2O, element sulfur or chalcopyrite. Then, surface properties of Acidithiobacillus ferrooxidans and chalcopyrite were analyzed by contact angle, zeta potential and Fourier transform infrared spectroscopy (FTIR). Adhesion force between bacteria and chalcopyrite was measured by atomic force microscopy (AFM). Attachment and bioleaching behaviors were also monitored. The results showed that A. ferrooxidans adapted with chalcopyrite exhibited the strongest adhesion force to chalcopyrite and the highest bioleaching rate. Culture adapted with sulfur bacteria took second place and FeSO4 · 7H2O-adapted bacteria were the lowest. Bioleaching rate and bacterial attachment capacity were positively related to bacterial adhesion force, which is affected by the nature of energy source. According to this work, the attachment of bacteria to chalcopyrite surface is one of the most important aspects that influence the bioleaching process of chalcopyrite. PMID:25511439

  10. Global transcriptional responses of Acidithiobacillus ferrooxidans Wenelen under different sulfide minerals.

    PubMed

    Latorre, Mauricio; Ehrenfeld, Nicole; Cortés, María Paz; Travisany, Dante; Budinich, Marko; Aravena, Andrés; González, Mauricio; Bobadilla-Fazzini, Roberto A; Parada, Pilar; Maass, Alejandro

    2016-01-01

    In order to provide new information about the adaptation of Acidithiobacillus ferrooxidans during the bioleaching process, the current analysis presents the first report of the global transcriptional response of the native copper mine strain Wenelen (DSM 16786) oxidized under different sulfide minerals. Microarrays were used to measure the response of At. ferrooxidans Wenelen to shifts from iron supplemented liquid cultures (reference state) to the addition of solid substrates enriched in pyrite or chalcopyrite. Genes encoding for energy metabolism showed a similar transcriptional profile for the two sulfide minerals. Interestingly, four operons related to sulfur metabolism were over-expressed during growth on a reduced sulfur source. Genes associated with metal tolerance (RND and ATPases type P) were up-regulated in the presence of pyrite or chalcopyrite. These results suggest that At. ferrooxidans Wenelen presents an efficient transcriptional system developed to respond to environmental conditions, namely the ability to withstand high copper concentrations. PMID:26476161

  11. Improved dewatering of CEPT sludge by biogenic flocculant from Acidithiobacillus ferrooxidans.

    PubMed

    Wong, Jonathan W C; Murugesan, Kumarasamy; Yu, Shuk Man; Kurade, Mayur B; Selvam, Ammaiyappan

    2016-01-01

    Bioleaching using an iron-oxidizing bacterium, Acidithiobacillus ferrooxidans, and its biogenic flocculants was evaluated to improve the dewaterability of chemically enhanced primary treatment (CEPT) sewage sludge. CEPT sludge in flasks was inoculated with A. ferrooxidans culture, medium-free cells and the cell-free culture filtrate with and without the energy substance Fe(2+), and periodically the sludge samples were analysed for the dewaterability. This investigation proves that bioleaching effectively improved the sludge dewaterability as evidenced from drastic reduction in capillary suction time (≤20 seconds) and specific resistance to filtration (≥90%); however, it requires an adaptability period of 1-2 days. On the other hand, the biogenic flocculant produced by A. ferrooxidans greatly decreased the time-to-filtration and facilitated the dewaterability within 4 h. Results indicate that rapid dewatering of CEPT sludge by biogenic flocculants provides an opportunity to replace the synthetic organic polymer for dewatering. PMID:26901727

  12. Bioleaching waste printed circuit boards by Acidithiobacillus ferrooxidans and its kinetics aspect.

    PubMed

    Yang, Yuankun; Chen, Shu; Li, Shicheng; Chen, Mengjun; Chen, Haiyan; Liu, Bijun

    2014-03-10

    In this paper, H(+) consumption and metal recovery, during the process of bioleaching waste printed circuit boards (WPCBs) by Acidithiobacillus ferrooxidans (A. ferrooxidans), were discussed in detail. When the WPCBs concentration was 15g/L, Cu (96.8%), Zn (83.8%), and Al (75.4%) were recovered after 72h by A. ferrooxidans. Experimental results indicated that metal recovery rate was significantly influenced by acid. Based on experimental results, the kinetics of the H(+) consumption and metal recovery on bioleaching WPCBs were represented by reaction kinetic equations. The kinetic of H(+) consumption could be described by the second-order kinetic model. The metal recovery belongs to the second-order model with adding acid, which was changed to the shrinking core model with precipitate production. PMID:24445171

  13. Transcriptional and functional studies of Acidithiobacillus ferrooxidans genes related to survival in the presence of copper.

    PubMed

    Navarro, Claudio A; Orellana, Luis H; Mauriaca, Cecilia; Jerez, Carlos A

    2009-10-01

    The acidophilic Acidithiobacillus ferrooxidans can resist exceptionally high copper (Cu) concentrations. This property is important for its use in biomining processes, where Cu and other metal levels range usually between 15 and 100 mM. To learn about the mechanisms that allow A. ferrooxidans cells to survive in this environment, a bioinformatic search of its genome showed the presence of at least 10 genes that are possibly related to Cu homeostasis. Among them are three genes coding for putative ATPases related to the transport of Cu (A. ferrooxidans copA1 [copA1(Af)], copA2(Af), and copB(Af)), three genes related to a system of the resistance nodulation cell division family involved in the extraction of Cu from the cell (cusA(Af), cusB(Af), and cusC(Af)), and two genes coding for periplasmic chaperones for this metal (cusF(Af) and copC(Af)). The expression of most of these open reading frames was studied by real-time reverse transcriptase PCR using A. ferrooxidans cells adapted for growth in the presence of high concentrations of Cu. The putative A. ferrooxidans Cu resistance determinants were found to be upregulated when this bacterium was exposed to Cu in the range of 5 to 25 mM. These A. ferrooxidans genes conferred to Escherichia coli a greater Cu resistance than wild-type cells, supporting their functionality. The results reported here and previously published data strongly suggest that the high resistance of the extremophilic A. ferrooxidans to Cu may be due to part or all of the following key elements: (i) a wide repertoire of Cu resistance determinants, (ii) the duplication of some of these Cu resistance determinants, (iii) the existence of novel Cu chaperones, and (iv) a polyP-based Cu resistance system. PMID:19666734

  14. Bioflotation of sulfide minerals with Acidithiobacillus ferrooxidans in relation to copper activation and surface oxidation.

    PubMed

    Pecina-Treviño, E T; Ramos-Escobedo, G T; Gallegos-Acevedo, P M; López-Saucedo, F J; Orrantia-Borunda, E

    2012-08-24

    Surface oxidation of sulfides and copper (Cu) activation are 2 of the main processes that determine the efficiency of flotation. The present study was developed with the intention to ascertain the role of the phenomena in the biomodification of sulfides by Acidithiobacillus ferrooxidans culture (cells and growth media) and their impact in bioflotation. Surface characteristics of chalcopyrite, sphalerite, and pyrrhotite, alone and in mixtures, after interaction with A. ferrooxidans were evaluated. Chalcopyrite floatability was increased substantially by biomodification, while bacteria depressed pyrrhotite floatability, favoring separation. The results showed that elemental sulfur concentration increased because of the oxidation generated by bacterial cells, the effect is intensified by the Fe(III) left in the culture and by galvanic contact. Acidithiobacillus ferrooxidans culture affects the Cu activation of sphalerite. The implications of elemental sulfur concentration and Cu activation of sphalerite are key factors that must be considered for the future development of sulfide bioflotation processes, since the depressive effect of cells could be counteracted by elemental sulfur generation. PMID:22920540

  15. Engineering the iron-oxidizing chemolithoautotroph Acidithiobacillus ferrooxidans for biochemical production.

    PubMed

    Kernan, Timothy; Majumdar, Sudipta; Li, Xiaozheng; Guan, Jingyang; West, Alan C; Banta, Scott

    2016-01-01

    There is growing interest in developing non-photosynthetic routes for the conversion of CO2 to fuels and chemicals. One underexplored approach is the transfer of energy to the metabolism of genetically modified chemolithoautotrophic bacteria. Acidithiobacillus ferrooxidans is an obligate chemolithoautotroph that derives its metabolic energy from the oxidation of iron or sulfur at low pH. Two heterologous biosynthetic pathways have been expressed in A. ferrooxidans to produce either isobutyric acid or heptadecane from CO2 and the oxidation of Fe(2+). A sevenfold improvement in productivity of isobutyric acid was obtained through improved media formulations in batch cultures. Steady-state efficiencies were lower in continuous cultures, likely due to ferric inhibition. If coupled to solar panels, the photon-to-fuel efficiency of this proof-of-principle process approaches estimates for agriculture-derived biofuels. These efforts lay the foundation for the utilization of this organism in the exploitation of electrical energy for biochemical synthesis. PMID:26174759

  16. Comparative proteomics of Acidithiobacillus ferrooxidans grown in the presence and absence of uranium.

    PubMed

    Dekker, Linda; Arsène-Ploetze, Florence; Santini, Joanne M

    2016-04-01

    Acidithiobacillus ferrooxidans is an acidophile that thrives in metal-contaminated environments and tolerates high levels of uranium. To gain a better understanding of the processes involved in U(VI) resistance, comparative proteomics was used. The proteome of A. ferrooxidans was grown in the presence and absence of 0.5 mM U(VI); expression of 17 proteins was upregulated and one was downregulated. Most proteins with increased expression are part of the general stress response or are involved in reactive oxygen species detoxification. Four novel proteins showed increased expression in the presence of U(VI) and may contribute to U(VI) resistance via thiol homoeostasis and U(VI) binding. PMID:26829305

  17. Use of Walnut Shell Powder to Inhibit Expression of Fe(2+)-Oxidizing Genes of Acidithiobacillus Ferrooxidans.

    PubMed

    Li, Yuhui; Liu, Yehao; Tan, Huifang; Zhang, Yifeng; Yue, Mei

    2016-01-01

    Acidithiobacillus ferrooxidans is a Gram-negative bacterium that obtains energy by oxidizing Fe(2+) or reduced sulfur compounds. This bacterium contributes to the formation of acid mine drainage (AMD). This study determined whether walnut shell powder inhibits the growth of A. ferrooxidans. First, the effects of walnut shell powder on Fe(2+) oxidization and H⁺ production were evaluated. Second, the chemical constituents of walnut shell were isolated to determine the active ingredient(s). Third, the expression of Fe(2+)-oxidizing genes and rus operon genes was investigated using real-time polymerase chain reaction. Finally, growth curves were plotted, and a bioleaching experiment was performed to confirm the active ingredient(s) in walnut shells. The results indicated that both walnut shell powder and the phenolic fraction exert high inhibitory effects on Fe(2+) oxidation and H⁺ production by A. ferrooxidans cultured in standard 9K medium. The phenolic components exert their inhibitory effects by down-regulating the expression of Fe(2+)-oxidizing genes and rus operon genes, which significantly decreased the growth of A. ferrooxidans. This study revealed walnut shell powder to be a promising substance for controlling AMD. PMID:27144574

  18. Use of Walnut Shell Powder to Inhibit Expression of Fe2+-Oxidizing Genes of Acidithiobacillus Ferrooxidans

    PubMed Central

    Li, Yuhui; Liu, Yehao; Tan, Huifang; Zhang, Yifeng; Yue, Mei

    2016-01-01

    Acidithiobacillus ferrooxidans is a Gram-negative bacterium that obtains energy by oxidizing Fe2+ or reduced sulfur compounds. This bacterium contributes to the formation of acid mine drainage (AMD). This study determined whether walnut shell powder inhibits the growth of A. ferrooxidans. First, the effects of walnut shell powder on Fe2+ oxidization and H+ production were evaluated. Second, the chemical constituents of walnut shell were isolated to determine the active ingredient(s). Third, the expression of Fe2+-oxidizing genes and rus operon genes was investigated using real-time polymerase chain reaction. Finally, growth curves were plotted, and a bioleaching experiment was performed to confirm the active ingredient(s) in walnut shells. The results indicated that both walnut shell powder and the phenolic fraction exert high inhibitory effects on Fe2+ oxidation and H+ production by A. ferrooxidans cultured in standard 9K medium. The phenolic components exert their inhibitory effects by down-regulating the expression of Fe2+-oxidizing genes and rus operon genes, which significantly decreased the growth of A. ferrooxidans. This study revealed walnut shell powder to be a promising substance for controlling AMD. PMID:27144574

  19. Comparison Analysis of Coal Biodesulfurization and Coal's Pyrite Bioleaching with Acidithiobacillus ferrooxidans

    PubMed Central

    Hong, Fen-Fen; He, Huan; Liu, Jin-Yan; Tao, Xiu-Xiang; Zheng, Lei; Zhao, Yi-Dong

    2013-01-01

    Acidithiobacillus ferrooxidans (A. ferrooxidans) was applied in coal biodesulfurization and coal's pyrite bioleaching. The result showed that A. ferrooxidans had significantly promoted the biodesulfurization of coal and bioleaching of coal's pyrite. After 16 days of processing, the total sulfur removal rate of coal was 50.6%, and among them the removal of pyritic sulfur was up to 69.9%. On the contrary, after 12 days of processing, the coal's pyrite bioleaching rate was 72.0%. SEM micrographs showed that the major pyrite forms in coal were massive and veinlets. It seems that the bacteria took priority to remove the massive pyrite. The sulfur relative contents analysis from XANES showed that the elemental sulfur (28.32%) and jarosite (18.99%) were accumulated in the biotreated residual coal. However, XRD and XANES spectra of residual pyrite indicated that the sulfur components were mainly composed of pyrite (49.34%) and elemental sulfur (50.72%) but no other sulfur contents were detected. Based on the present results, we speculated that the pyrite forms in coal might affect sulfur biooxidation process. PMID:24288464

  20. Zinc bioleaching from an iron concentrate using Acidithiobacillus ferrooxidans strain from Hercules Mine of Coahuila, Mexico

    NASA Astrophysics Data System (ADS)

    Núñez-Ramírez, Diola Marina; Solís-Soto, Aquiles; López-Miranda, Javier; Pereyra-Alférez, Benito; Rutiaga-Quiñónes, Miriam; Medina-Torres, Luis; Medrano-Roldán, Hiram

    2011-10-01

    The iron concentrate from Hercules Mine of Coahuila, Mexico, which mainly contained pyrite and pyrrhotite, was treated by the bioleaching process using native strain Acidithiobacillus ferrooxidans ( A. ferrooxidans) to determine the ability of these bacteria on the leaching of zinc. The native bacteria were isolated from the iron concentrate of the mine. The bioleaching experiments were carried out in shake flasks to analyze the effects of pH values, pulp density, and the ferrous sulfate concentration on the bioleaching process. The results obtained by microbial kinetic analyses for the evaluation of some aspects of zinc leaching show that the native bacteria A. ferrooxidans, which is enriched with a 9K Silverman medium under the optimum conditions of pH 2.0, 20 g/L pulp density, and 40 g/L FeSO4, increases the zinc extraction considerably observed by monitoring during15 d, i.e., the zinc concentration has a decrease of about 95% in the iron concentrate.

  1. Microarray and bioinformatic analyses suggest models for carbon metabolism in the autotroph Acidithiobacillus ferrooxidans

    SciTech Connect

    C. Appia-ayme; R. Quatrini; Y. Denis; F. Denizot; S. Silver; F. Roberto; F. Veloso; J. Valdes; J. P. Cardenas; M. Esparza; O. Orellana; E. Jedlicki; V. Bonnefoy; D. Holmes

    2006-09-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic bacterium that uses iron or sulfur as an energy and electron source. Bioinformatic analysis was used to identify putative genes and potential metabolic pathways involved in CO2 fixation, 2P-glycolate detoxification, carboxysome formation and glycogen utilization in At. ferrooxidans. Microarray transcript profiling was carried out to compare the relative expression of the predicted genes of these pathways when the microorganism was grown in the presence of iron versus sulfur. Several gene expression patterns were confirmed by real-time PCR. Genes for each of the above predicted pathways were found to be organized into discrete clusters. Clusters exhibited differential gene expression depending on the presence of iron or sulfur in the medium. Concordance of gene expression within each cluster, suggested that they are operons Most notably, clusters of genes predicted to be involved in CO2 fixation, carboxysome formation, 2P-glycolate detoxification and glycogen biosynthesis were up-regulated in sulfur medium, whereas genes involved in glycogen utilization were preferentially expressed in iron medium. These results can be explained in terms of models of gene regulation that suggest how A. ferrooxidans can adjust its central carbon management to respond to changing environmental conditions.

  2. Immobilization of arsenite and ferric iron by Acidithiobacillus ferrooxidans and its relevance to acid mine drainage.

    PubMed

    Duquesne, K; Lebrun, S; Casiot, C; Bruneel, O; Personné, J-C; Leblanc, M; Elbaz-Poulichet, F; Morin, G; Bonnefoy, V

    2003-10-01

    Weathering of the As-rich pyrite-rich tailings of the abandoned mining site of Carnoulès (southeastern France) results in the formation of acid waters heavily loaded with arsenic. Dissolved arsenic present in the seepage waters precipitates within a few meters from the bottom of the tailing dam in the presence of microorganisms. An Acidithiobacillus ferrooxidans strain, referred to as CC1, was isolated from the effluents. This strain was able to remove arsenic from a defined synthetic medium only when grown on ferrous iron. This A. ferrooxidans strain did not oxidize arsenite to arsenate directly or indirectly. Strain CC1 precipitated arsenic unexpectedly as arsenite but not arsenate, with ferric iron produced by its energy metabolism. Furthermore, arsenite was almost not found adsorbed on jarosite but associated with a poorly ordered schwertmannite. Arsenate is known to efficiently precipitate with ferric iron and sulfate in the form of more or less ordered schwertmannite, depending on the sulfur-to-arsenic ratio. Our data demonstrate that the coprecipitation of arsenite with schwertmannite also appears as a potential mechanism of arsenite removal in heavily contaminated acid waters. The removal of arsenite by coprecipitation with ferric iron appears to be a common property of the A. ferrooxidans species, as such a feature was observed with one private and three collection strains, one of which was the type strain. PMID:14532077

  3. Immobilization of Arsenite and Ferric Iron by Acidithiobacillus ferrooxidans and Its Relevance to Acid Mine Drainage

    PubMed Central

    Duquesne, K.; Lebrun, S.; Casiot, C.; Bruneel, O.; Personné, J.-C.; Leblanc, M.; Elbaz-Poulichet, F.; Morin, G.; Bonnefoy, V.

    2003-01-01

    Weathering of the As-rich pyrite-rich tailings of the abandoned mining site of Carnoulès (southeastern France) results in the formation of acid waters heavily loaded with arsenic. Dissolved arsenic present in the seepage waters precipitates within a few meters from the bottom of the tailing dam in the presence of microorganisms. An Acidithiobacillus ferrooxidans strain, referred to as CC1, was isolated from the effluents. This strain was able to remove arsenic from a defined synthetic medium only when grown on ferrous iron. This A. ferrooxidans strain did not oxidize arsenite to arsenate directly or indirectly. Strain CC1 precipitated arsenic unexpectedly as arsenite but not arsenate, with ferric iron produced by its energy metabolism. Furthermore, arsenite was almost not found adsorbed on jarosite but associated with a poorly ordered schwertmannite. Arsenate is known to efficiently precipitate with ferric iron and sulfate in the form of more or less ordered schwertmannite, depending on the sulfur-to-arsenic ratio. Our data demonstrate that the coprecipitation of arsenite with schwertmannite also appears as a potential mechanism of arsenite removal in heavily contaminated acid waters. The removal of arsenite by coprecipitation with ferric iron appears to be a common property of the A. ferrooxidans species, as such a feature was observed with one private and three collection strains, one of which was the type strain. PMID:14532077

  4. Bioinformatic Prediction of Gene Functions Regulated by Quorum Sensing in the Bioleaching Bacterium Acidithiobacillus ferrooxidans

    PubMed Central

    Banderas, Alvaro; Guiliani, Nicolas

    2013-01-01

    The biomining bacterium Acidithiobacillus ferrooxidans oxidizes sulfide ores and promotes metal solubilization. The efficiency of this process depends on the attachment of cells to surfaces, a process regulated by quorum sensing (QS) cell-to-cell signalling in many Gram-negative bacteria. At. ferrooxidans has a functional QS system and the presence of AHLs enhances its attachment to pyrite. However, direct targets of the QS transcription factor AfeR remain unknown. In this study, a bioinformatic approach was used to infer possible AfeR direct targets based on the particular palindromic features of the AfeR binding site. A set of Hidden Markov Models designed to maintain palindromic regions and vary non-palindromic regions was used to screen for putative binding sites. By annotating the context of each predicted binding site (PBS), we classified them according to their positional coherence relative to other putative genomic structures such as start codons, RNA polymerase promoter elements and intergenic regions. We further used the Multiple EM for Motif Elicitation algorithm (MEME) to further filter out low homology PBSs. In summary, 75 target-genes were identified, 34 of which have a higher confidence level. Among the identified genes, we found afeR itself, zwf, genes encoding glycosyltransferase activities, metallo-beta lactamases, and active transport-related proteins. Glycosyltransferases and Zwf (Glucose 6-phosphate-1-dehydrogenase) might be directly involved in polysaccharide biosynthesis and attachment to minerals by At. ferrooxidans cells during the bioleaching process. PMID:23959118

  5. Bioinformatic prediction of gene functions regulated by quorum sensing in the bioleaching bacterium Acidithiobacillus ferrooxidans.

    PubMed

    Banderas, Alvaro; Guiliani, Nicolas

    2013-01-01

    The biomining bacterium Acidithiobacillus ferrooxidans oxidizes sulfide ores and promotes metal solubilization. The efficiency of this process depends on the attachment of cells to surfaces, a process regulated by quorum sensing (QS) cell-to-cell signalling in many Gram-negative bacteria. At. ferrooxidans has a functional QS system and the presence of AHLs enhances its attachment to pyrite. However, direct targets of the QS transcription factor AfeR remain unknown. In this study, a bioinformatic approach was used to infer possible AfeR direct targets based on the particular palindromic features of the AfeR binding site. A set of Hidden Markov Models designed to maintain palindromic regions and vary non-palindromic regions was used to screen for putative binding sites. By annotating the context of each predicted binding site (PBS), we classified them according to their positional coherence relative to other putative genomic structures such as start codons, RNA polymerase promoter elements and intergenic regions. We further used the Multiple EM for Motif Elicitation algorithm (MEME) to further filter out low homology PBSs. In summary, 75 target-genes were identified, 34 of which have a higher confidence level. Among the identified genes, we found afeR itself, zwf, genes encoding glycosyltransferase activities, metallo-beta lactamases, and active transport-related proteins. Glycosyltransferases and Zwf (Glucose 6-phosphate-1-dehydrogenase) might be directly involved in polysaccharide biosynthesis and attachment to minerals by At. ferrooxidans cells during the bioleaching process. PMID:23959118

  6. Differential gene expression in Acidithiobacillus ferrooxidans LR planktonic and attached cells in the presence of chalcopyrite.

    PubMed

    Ossa Henao, Diana Marcela; Vicentini, Renato; Rodrigues, Viviane Drumond; Bevilaqua, Denise; Ottoboni, Laura Maria Mariscal

    2014-07-01

    Acidithiobacillus ferrooxidans is commonly used in bioleaching operations to recover copper from sulfide ores. It is commonly accepted that A. ferrooxidans attaches to mineral surfaces by means of extracellular polymeric substances (EPS), however the role of type IV pili and tight adherence genes in this process is poorly understood. Genes related to the formation of type IV pili and tight adherence were identified in the genome of the bacterium, and in this work, we show that A. ferrooxidans actively expresses these genes, as demonstrated by quantitative real-time PCR analysis using cells incubated with chalcopyrite for 2 h. Significant differences in gene expression were observed between planktonic and adhered cells, with the level of expression being much greater in planktonic cells. These results might indicate that planktonic cells can actively adhere to the substrate. A bioinformatics analysis of interaction networks of the tight adherence and type IV pilus assembly genes revealed a strong relationship between conjugation systems (tra operon) and regulatory systems (PilR, PilS). PMID:24523248

  7. K30, H150, and H168 are essential residues for coordinating pyridoxal 5'-phosphate of O-acetylserine sulfhydrylase from Acidithiobacillus ferrooxidans.

    PubMed

    Zheng, Chunli; Nie, Li; Qian, Lin; Wang, Zhilou; Liu, Guizhen; Liu, Jianshe

    2010-06-01

    O-acetylserine sulfhydrylase (OASS) is a key enzyme involved in the pathway of the cysteine biosynthesis. The gene of OASS from Acidithiobacillus ferrooxidans ATCC 23270 was cloned and expressed in E. coli, the soluble protein was purified by one-step affinity chromatography to apparent homogeneity. Colors and UV-vis scanning results of the recombinant protein confirmed that it was a pyridoxal 5'-phosphate (PLP)-containing protein. Sequence alignment and site-directed mutation of the enzyme revealed that the cofactor PLP is covalently bound in Schiff base linkage with K30, as well as the two residues H150 and H168 were the crucial residues for PLP binding and stabilization. PMID:20033172

  8. Genomic insights into the iron uptake mechanisms of the biomining microorganism Acidithiobacillus ferrooxidans.

    PubMed

    Quatrini, Raquel; Jedlicki, Eugenia; Holmes, David S

    2005-12-01

    Commercial bioleaching of copper and the biooxidation of gold is a cost-effective and environmentally friendly process for metal recovery. A partial genome sequence of the acidophilic, bioleaching bacterium Acidithiobacillus ferrooxidans is available from two public sources. This information has been used to build preliminary models that describe how this microorganism confronts unusually high iron loads in the extremely acidic conditions (pH 2) found in natural environments and in bioleaching operations. A. ferrooxidans contains candidate genes for iron uptake, sensing, storage, and regulation of iron homeostasis. Predicted proteins exhibit significant amino acid similarity with known proteins from neutrophilic organisms, including conservation of functional motifs, permitting their identification by bioinformatics tools and allowing the recognition of common themes in iron transport across distantly related species. However, significant differences in amino acid sequence were detected in pertinent domains that suggest ways in which the periplasmic and outer membrane proteins of A. ferrooxidans maintain structural integrity and relevant protein-protein contacts at low pH. Unexpectedly, the microorganism also contains candidate genes, organized in operon-like structures that potentially encode at least 11 siderophore systems for the uptake of Fe(III), although it does not exhibit genes that could encode the biosynthesis of the siderophores themselves. The presence of multiple Fe(III) uptake systems suggests that A. ferrooxidans can inhabit aerobic environments where iron is scarce and where siderophore producers are present. It may also help to explain why it cannot tolerate high Fe(III) concentrations in bioleaching operations where it is out-competed by Leptospirillum species. PMID:15895264

  9. Purification and characterization of sulfide:quinone oxidoreductase from an acidophilic iron-oxidizing bacterium, Acidithiobacillus ferrooxidans.

    PubMed

    Wakai, Satoshi; Tsujita, Mizuho; Kikumoto, Mei; Manchur, Mohammed A; Kanao, Tadayoshi; Kamimura, Kazuo

    2007-11-01

    Sulfide:quinone oxidoreductase (SQR) was purified from membrane of acidophilic chemolithotrophic bacterium Acidithiobacillus ferrooxidans NASF-1 cells grown on sulfur medium. It was composed of a single polypeptide with an apparent molecular mass of 47 kDa. The apparent K(m) values for sulfide and ubiquinone were 42 and 14 muM respectively. The apparent optimum pH for the SQR activity was about 7.0. A gene encoding a putative SQR of A. ferrooxidans NASF-1 was cloned and sequenced. The gene was expressed in Escherichia coli as a thioredoxin-fusion protein in inclusion bodies in an inactive form. A polyclonal antibody prepared against the recombinant protein reacted immunologically with the purified SQR. Western blotting analysis using the antibody revealed an increased level of SQR synthesis in sulfur-grown A. ferrooxidans NASF-1 cells, implying the involvement of SQR in elemental sulfur oxidation in sulfur-grown A. ferrooxidans NASF-1 cells. PMID:17986789

  10. Sludge conditioning using biogenic flocculant produced by Acidithiobacillus ferrooxidans for enhancement in dewaterability.

    PubMed

    Kurade, Mayur B; Murugesan, Kumarasamy; Selvam, Ammaiyappan; Yu, Shuk-Man; Wong, Jonathan W C

    2016-10-01

    Biogenic flocculant produced by Acidithiobacillus ferrooxidans was used for sludge conditioning to improve the dewaterability of anaerobically-digested sludge, and its efficiency was compared with commercial cationic polyacrylamide (PAM). Biogenic flocculant rapidly reduced the pH and increased the oxidation-reduction potential of sludge. Capillary suction time (CST) and specific resistant to filtration (SRF) of sludge was decreased by 74% and 89%, respectively, compared with control; and the reductions were 58% CST and 67% SRF higher when compared with commercial polymer. Biogenic treatment improved the sludge calorific value by 13%, and also reduced the unpleasant odor. The small-scale mechanical filter press study showed that the biogenic flocculant can reduce the moisture content of sludge to 70%, and improve the clarity of the filtrate in terms of removal of total suspended solids and total dissolved solids when compared with synthetic polymer treatment. PMID:27020124

  11. Study of Acidithiobacillus ferrooxidans and enzymatic bio-Fenton process-mediated corrosion of copper-nickel alloy.

    PubMed

    Jadhav, U; Hocheng, H

    2016-10-01

    This study presents the corrosion behavior of the copper-nickel (Cu-Ni) alloy in the presence of Acidithiobacillus ferrooxidans (A. ferrooxidans) and glucose oxidase (GOx) enzyme. In both the cases ferric ions played an important role in weight loss and thereby to carry out the corrosion of the Cu-Ni alloy. A corrosion rate of 0.6 (±0.008), 2.11 (±0.05), 3.69 (±0.26), 0.7 (±0.006) and 0.08 (±0.002) mm/year was obtained in 72 h using 9K medium with ferrous sulfate, A. ferrooxidans culture supernatant, A. ferrooxidans cells, GOx enzyme and hydrogen peroxide (H2O2) solution respectively. The scanning electron microscopy (SEM) micrographs showed that a variable extent of corrosion was caused by 9K medium with ferrous sulfate, GOx and A. ferrooxidans cells. An arithmetic average surface roughness (Ra) of 174.78 nm was observed for the control work-piece using optical profilometer. The change in Ra was observed with the treatment of the Cu-Ni alloy using various systems. The Ra for 9K medium with ferrous sulfate, GOx and A. ferrooxidans cells was 374.54, 607.32 and 799.48 nm, respectively, after 24 h. These results suggest that A. ferrooxidans cells were responsible for more corrosion of the Cu-Ni alloy than other systems used. PMID:26930447

  12. The chemolithoautotroph Acidithiobacillus ferrooxidans can survive under phosphate-limiting conditions by expressing a C-P lyase operon that allows it to grow on phosphonates.

    PubMed

    Vera, Mario; Pagliai, Fernando; Guiliani, Nicolas; Jerez, Carlos A

    2008-03-01

    The chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans is of great importance in biomining operations. During the bioleaching of ores, microorganisms are subjected to a variety of environmental stresses and to the limitations of some nutrients, such as inorganic phosphate (P(i)), which is an essential component for all living cells. Although the primary source of phosphorus for microorganisms is P(i), some bacteria are also able to metabolize P(i) esters (with a C-O-P bond) and phosphonates (with a very inert C-P bond). By using bioinformatic analysis of genomic sequences of the type strain of A. ferrooxidans (ATCC 23270), we found that as part of a Pho regulon, this bacterium has a complete gene cluster encoding C-P lyase, which is the main bacterial enzyme involved in phosphonate (Pn) degradation in other microorganisms. A. ferrooxidans was able to grow in the presence of methyl-Pn or ethyl-Pn as an alternative phosphorus source. Under these growth conditions, a great reduction in inorganic polyphosphate (polyP) levels was seen compared with the level for cells grown in the presence of P(i). By means of reverse transcription-PCR (RT-PCR), DNA macroarrays, and real-time RT-PCR experiments, it was found that A. ferrooxidans phn genes were cotranscribed and their expression was induced when the microorganism was grown in methyl-Pn as the only phosphorus source. This is the first report of phosphonate utilization in a chemolithoautotrophic microorganism. The existence of a functional C-P lyase system is a clear advantage for the survival under P(i) limitation, a condition that may greatly affect the bioleaching of ores. PMID:18203861

  13. Growth of the acidophilic iron-sulfur bacterium Acidithiobacillus ferrooxidans under Mars-like geochemical conditions

    NASA Astrophysics Data System (ADS)

    Bauermeister, Anja; Rettberg, Petra; Flemming, Hans-Curt

    2014-08-01

    The question of life on Mars has been in focus of astrobiological research for several decades, and recent missions in orbit or on the surface of the planet are constantly expanding our knowledge on Martian geochemistry. For example, massive stratified deposits have been identified on Mars containing sulfate minerals and iron oxides, which suggest the existence of acidic aqueous conditions in the past, similar to acidic iron- and sulfur-rich environments on Earth. Acidophilic organisms thriving in such habitats could have been an integral part of a possibly widely extinct Martian ecosystem, but remains might possibly even exist today in protected subsurface niches. The chemolithoautotrophic strain Acidithiobacillus ferrooxidans was selected as a model organism to study the metabolic capacities of acidophilic iron-sulfur bacteria, especially regarding their ability to grow with in situ resources that could be expected on Mars. The experiments were not designed to accurately simulate Martian physical conditions (except when certain single parameters such as oxygen partial pressure were considered), but rather the geochemical environment that can be found on Mars. A. ferrooxidans could grow solely on the minerals contained in synthetic Mars regolith mixtures with no added nutrients, using either O2 as an external electron acceptor for iron oxidation, or H2 as an external electron donor for iron reduction, and thus might play important roles in the redox cycling of iron on Mars. Though the oxygen partial pressure of the Martian atmosphere at the surface was not sufficient for detectable iron oxidation and growth of A. ferrooxidans during short-term incubation (7 days), alternative chemical O2-generating processes in the subsurface might yield microhabitats enriched in oxygen, which principally are possible under such conditions. The bacteria might also contribute to the reductive dissolution of Fe3+-containing minerals like goethite and hematite, which are

  14. Optimization of magnetosome production by Acidithiobacillus ferrooxidans using desirability function approach.

    PubMed

    Yan, Lei; Zhang, Shuang; Liu, Hetao; Wang, Weidong; Chen, Peng; Li, Hongyu

    2016-02-01

    Present study aimed to resolve the conflict between cell growth and magnetosome formation of Acidithiobacillus ferrooxidans (A. ferrooxidans) in batch experiments by applying response surface methodology (RSM) integrated a desirability function approach. The effects of several operating parameters on cell growth (OD600) and magnetosome production (Cmag) were evaluated. The maximum overall desirability (D) of 0.923 was achieved at iron concentration of 125.07mM, shake speed of 122.37rpm and nitrogen concentration of 2.40g/L. Correspondingly, the OD600 and Cmag were 0.522 and 1.196, respectively. The confirmation experiment confirmed that the optimum OD600 and Cmag obtained were in good agreement with the predicted values. The inductively coupled plasma atomic emission spectrometer (ICP-AES) and transmission electron microscopy (TEM) analyses revealed that the production of magnetosomes could be improved via optimization. X-ray diffraction (XRD) showed the magnetosomes are magnetite. Results indicated that RSM with a desirability function was a useful technique to get the maximum OD600 and Cmag simultaneously. PMID:26652427

  15. Column bioleaching copper and its kinetics of waste printed circuit boards (WPCBs) by Acidithiobacillus ferrooxidans.

    PubMed

    Chen, Shu; Yang, Yuankun; Liu, Congqiang; Dong, Faqin; Liu, Bijun

    2015-12-01

    Application of bioleaching process for metal recovery from electronic waste has received an increasing attention in recent years. In this work, a column bioleaching of copper from waste printed circuit boards (WPCBs) by Acidithiobacillus ferrooxidans has been investigated. After column bioleaching for 28d, the copper recovery reached at 94.8% from the starting materials contained 24.8% copper. Additionally, the concentration of Fe(3+) concentration varied significantly during bioleaching, which inevitably will influence the Cu oxidation, thus bioleaching process. Thus the variation in Fe(3+) concentration should be taken into consideration in the conventional kinetic models of bioleaching process. Experimental results show that the rate of copper dissolution is controlled by external diffusion rather than internal one because of the iron hydrolysis and formation of jarosite precipitates at the surface of the material. The kinetics of column bioleaching WPCBs remains unchanged because the size and morphology of precipitates are unaffected by maintaining the pH of solution at 2.25 level. In bioleaching process, the formation of jarosite precipitate can be prevented by adding dilute sulfuric acid and maintaining an acidic condition of the leaching medium. In such way, the Fe(2)(+)-Fe(3+) cycle process can kept going and create a favorable condition for Cu bioleaching. Our experimental results show that column Cu bioleaching from WPCBs by A. ferrooxidans is promising. PMID:26196406

  16. Characterization of iron-sulfur cluster assembly protein IscA from Acidithiobacillus ferrooxidans.

    PubMed

    Qian, Lin; Zheng, Chunli; Liu, Jianshe

    2013-03-01

    IscA is a key member of the iron-sulfur cluster assembly machinery found in bacteria and eukaryotes, but the mechanism of its function in the biogenesis of iron-sulfur cluster remains elusive. In this paper, we demonstrate that Acidithiobacillus ferrooxidans IscA is a [4Fe-4S] cluster binding protein, and it can bind iron in the presence of DTT with an apparent iron association constant of 4·10(20) M(-1). The iron binding in IscA can be promoted by oxygen through oxidizing ferrous iron to ferric iron. Furthermore, we show that the iron bound form of IscA can be converted to iron-sulfur cluster bound form in the presence of IscS and L-cysteine in vitro. Substitution of the invariant cysteine residues Cys35, Cys99, or Cys101 in IscA abolishes the iron binding activity of the protein; the IscA mutants that fail to bind iron are unable to assemble the iron-sulfur clusters. Further studies indicate that the iron-loaded IscA could act as an iron donor for the assembly of iron-sulfur clusters in the scaffold protein IscU in vitro. Taken together, these findings suggest that A. ferrooxidans IscA is not only an iron-sulfur protein, but also an iron binding protein that can act as an iron donor for biogenesis of iron-sulfur clusters. PMID:23586717

  17. Anaerobic Sulfur Metabolism Coupled to Dissimilatory Iron Reduction in the Extremophile Acidithiobacillus ferrooxidans

    PubMed Central

    Osorio, Héctor; Mangold, Stefanie; Denis, Yann; Ñancucheo, Ivan; Esparza, Mario; Johnson, D. Barrie; Bonnefoy, Violaine; Dopson, Mark

    2013-01-01

    Gene transcription (microarrays) and protein levels (proteomics) were compared in cultures of the acidophilic chemolithotroph Acidithiobacillus ferrooxidans grown on elemental sulfur as the electron donor under aerobic and anaerobic conditions, using either molecular oxygen or ferric iron as the electron acceptor, respectively. No evidence supporting the role of either tetrathionate hydrolase or arsenic reductase in mediating the transfer of electrons to ferric iron (as suggested by previous studies) was obtained. In addition, no novel ferric iron reductase was identified. However, data suggested that sulfur was disproportionated under anaerobic conditions, forming hydrogen sulfide via sulfur reductase and sulfate via heterodisulfide reductase and ATP sulfurylase. Supporting physiological evidence for H2S production came from the observation that soluble Cu2+ included in anaerobically incubated cultures was precipitated (seemingly as CuS). Since H2S reduces ferric iron to ferrous in acidic medium, its production under anaerobic conditions indicates that anaerobic iron reduction is mediated, at least in part, by an indirect mechanism. Evidence was obtained for an alternative model implicating the transfer of electrons from S0 to Fe3+ via a respiratory chain that includes a bc1 complex and a cytochrome c. Central carbon pathways were upregulated under aerobic conditions, correlating with higher growth rates, while many Calvin-Benson-Bassham cycle components were upregulated during anaerobic growth, probably as a result of more limited access to carbon dioxide. These results are important for understanding the role of A. ferrooxidans in environmental biogeochemical metal cycling and in industrial bioleaching operations. PMID:23354702

  18. Immobilization of Acidithiobacillus ferrooxidans on Cotton Gauze for the Bioleaching of Waste Printed Circuit Boards.

    PubMed

    Nie, Hongyan; Zhu, Nengwu; Cao, Yanlan; Xu, Zhiguo; Wu, Pingxiao

    2015-10-01

    The bioleaching parameters of metal concentrates from waste printed circuit boards by Acidithiobacillus ferrooxidans immobilized on cotton gauze in a two-step reactor were investigated in this study. The results indicated that an average ferrous iron oxidation rate of 0.54 g/(L·h) and a ferrous iron oxidation ratio of 96.90 % were obtained after 12 h at aeration rate of 1 L/min in bio-oxidation reactor. After 96 h, the highest leaching efficiency of copper reached 91.68 % under the conditions of the content of the metal powder 12 g/L, the retention time 6 h, and the aeration rate 1 L/min. The bioleaching efficiency of copper could be above 91.12 % under repeated continuous batch operation. Meanwhile, 95.32 % of zinc, 90.32 % of magnesium, 86.31 % of aluminum, and 59.07 % of nickel were extracted after 96 h. All the findings suggested that the recovery of metal concentrates from waste printed circuit boards via immobilization of A. ferrooxidans on cotton gauze was feasible. PMID:26239442

  19. Cr and Ni recovery during bioleaching of dewatered metal-plating sludge using Acidithiobacillus ferrooxidans.

    PubMed

    Rastegar, S O; Mousavi, S M; Shojaosadati, S A

    2014-09-01

    This study determined the optimal conditions required to attain maximum metal recovery in the bioleaching process of dewatered metal-plating sludge using Acidithiobacillus ferrooxidans (A. ferrooxidans). Adaptation of this strain was carried up to 1% (w/v) of the sample. Three factors including initial pH, initial Fe(3+) concentration and pulp density were selected as the effective factors and were optimized using a central composite design of response surface methodology. An initial pH of 1, pulp density of 9 g/l and initial Fe(3+) concentration of 1g/l were determined to be optimum values by the statistical models. The highest extractions for Cr and Ni under optimal conditions were 55.6% and 58.2%, respectively. Bioleaching kinetics was investigated using a modified shrinking core model to better understand the mechanism of the leaching reaction. The model predictions indicate that the diffusion step controlled the overall dissolution kinetics and is the rate controlling step. PMID:24971945

  20. Metabolic reconstruction of sulfur assimilation in the extremophile Acidithiobacillus ferrooxidans based on genome analysis

    PubMed Central

    Valdés, Jorge; Veloso, Felipe; Jedlicki, Eugenia; Holmes, David

    2003-01-01

    Background Acidithiobacillus ferrooxidans is a gamma-proteobacterium that lives at pH2 and obtains energy by the oxidation of sulfur and iron. It is used in the biomining industry for the recovery of metals and is one of the causative agents of acid mine drainage. Effective tools for the study of its genetics and physiology are not in widespread use and, despite considerable effort, an understanding of its unusual physiology remains at a rudimentary level. Nearly complete genome sequences of A. ferrooxidans are available from two public sources and we have exploited this information to reconstruct aspects of its sulfur metabolism. Results Two candidate mechanisms for sulfate uptake from the environment were detected but both belong to large paralogous families of membrane transporters and their identification remains tentative. Prospective genes, pathways and regulatory mechanisms were identified that are likely to be involved in the assimilation of sulfate into cysteine and in the formation of Fe-S centers. Genes and regulatory networks were also uncovered that may link sulfur assimilation with nitrogen fixation, hydrogen utilization and sulfur reduction. Potential pathways were identified for sulfation of extracellular metabolites that may possibly be involved in cellular attachment to pyrite, sulfur and other solid substrates. Conclusions A bioinformatic analysis of the genome sequence of A. ferrooxidans has revealed candidate genes, metabolic process and control mechanisms potentially involved in aspects of sulfur metabolism. Metabolic modeling provides an important preliminary step in understanding the unusual physiology of this extremophile especially given the severe difficulties involved in its genetic manipulation and biochemical analysis. PMID:14675496

  1. Significance of Oxygen Supply in Jarosite Biosynthesis Promoted by Acidithiobacillus ferrooxidans

    PubMed Central

    Liang, Jianru; Zhou, Lixiang

    2015-01-01

    Jarosite [(Na+, K+, NH4+, H3O+)Fe3(SO4)2(OH)6] is an efficient scavenger for trace metals in Fe- and SO42--rich acidic water. During the biosynthesis of jarosite promoted by Acidithiobacillus ferrooxidans, the continuous supply of high oxygen levels is a common practice that results in high costs. To evaluate the function of oxygen in jarosite production by A. ferrooxidans, three groups of batch experiments with different oxygen supply levels (i.e., loading volume percentages of FeSO4 solution of 20%, 40%, and 70% v/v in the flasks), as well as three groups of sealed flask experiments with different limiting oxygen supply conditions (i.e., the solutions were not sealed at the initial stage of the ferrous oxidation reaction by paraffin but were rather sealed at the end of the ferrous oxidation reaction at 48 h), were tested. The formed Fe-precipitates were characterized via X-ray powder diffraction and scanning electron microscope-energy dispersive spectral analysis. The results showed that the biosynthesis of jarosite by A. ferrooxidans LX5 could be achieved at a wide range of solution loading volume percentages. The rate and efficiency of the jarosite biosynthesis were poorly correlated with the concentration of dissolved oxygen in the reaction solution. Similar jarosite precipitates, expressed as KFe3 (SO4) 2(OH)6 with Fe/S molar ratios between 1.61 and 1.68, were uniformly formed in unsealed and 48 h sealed flasks. These experimental results suggested that the supply of O2 was only essential in the period of the oxidation of ferrous iron to ferric but was not required in the period of ferric precipitation. PMID:25807372

  2. Draft genome sequence of extremely acidophilic bacterium Acidithiobacillus ferrooxidans DLC-5 isolated from acid mine drainage in Northeast China.

    PubMed

    Chen, Peng; Yan, Lei; Wu, Zhengrong; Xu, Ruixiang; Li, Suyue; Wang, Ningbo; Liang, Ning; Li, Hongyu

    2015-12-01

    Acidithiobacillus ferrooxidans type strain DLC-5, isolated from Wudalianchi in Heihe of Heilongjiang Province, China. Here, we present the draft genome of strain DLC-5 which contains 4,232,149 bp in 2745 contigs with 57.628% GC content and includes 32,719 protein-coding genes and 64 tRNA-encoding genes. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. JNNH00000000.1. PMID:26697393

  3. Draft genome sequence of extremely acidophilic bacterium Acidithiobacillus ferrooxidans DLC-5 isolated from acid mine drainage in Northeast China

    PubMed Central

    Chen, Peng; Yan, Lei; Wu, Zhengrong; Xu, Ruixiang; Li, Suyue; Wang, Ningbo; Liang, Ning; Li, Hongyu

    2015-01-01

    Acidithiobacillus ferrooxidans type strain DLC-5, isolated from Wudalianchi in Heihe of Heilongjiang Province, China. Here, we present the draft genome of strain DLC-5 which contains 4,232,149 bp in 2745 contigs with 57.628% GC content and includes 32,719 protein-coding genes and 64 tRNA-encoding genes. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. JNNH00000000.1. PMID:26697393

  4. Synthesis of argentojarosite with simulated bioleaching solutions produced by Acidithiobacillus ferrooxidans.

    PubMed

    Mukherjee, Chiranjit; Jones, F Sandy; Bigham, Jerry M; Tuovinen, Olli H

    2016-09-01

    Argentojarosite (AgFe3(SO4)2(OH)6) is formed as a secondary phase in Ag-catalyzed bioleaching of chalcopyrite (CuFeS2), but to date very little is known about the paragenesis or characteristics of this silver-containing compound. The purpose of this study was to synthesize argentojarosite via biological oxidation of 120mM ferrous sulfate by Acidithiobacillus ferrooxidans. Because of its toxicity to A. ferrooxidans, Ag(+) (as AgNO3) was added to spent culture media (pH2) after complete oxidation of ferrous sulfate. Schwertmannite (ideally Fe8O8(OH)6(SO4)) was precipitated during the iron oxidation phase, and subsequent Ag(+) addition resulted in the formation of argentojarosite. Contact time (8h, 5d, and 14d) and Ag(+) concentration (0, 5, 20, and 40mM) were used as variables in these experiments. Synthesis of argentojarosite, schwertmannite and other mineral phases was confirmed through X-ray diffraction analysis. Additional analyses of solid-phase oxidation products included elemental composition, color and specific surface area. The sample synthesized in the presence of 40mM Ag(+) and with 14d contact time yielded an X-ray diffraction pattern of well crystallized argentojarosite, and its elemental composition closely matched the calculated Ag, Fe, and S contents of ideal argentojarosite. The color and surface area of the remaining samples were influenced by the presence of residual schwertmannite. This phase remained stable over the time course of 14d when no Ag(+) was present in the system. When equilibrations were extended to 42d, partial conversion of reference schwertmannite to goethite was noted in the absence of Ag. In the presence of 20mM or 40mM Ag over the same time course, some formation of argentojarosite was also noted. In this case, schwertmannite was the only source of Fe and SO4 for argentojarosite formation. PMID:27207050

  5. Metal resistance-related genes are differently expressed in response to copper and zinc ion in six Acidithiobacillus ferrooxidans strains.

    PubMed

    Wu, Xueling; Zhang, Zhenzhen; Liu, Lili; Deng, Fanfan; Liu, Xinxing; Qiu, Guanzhou

    2014-12-01

    Metal resistance of acidophilic bacteria is very significant during bioleaching of copper ores since high concentration of metal is harmful to the growth of microorganisms. The resistance levels of six Acidithiobacillus ferrooxidans strains to 0.15 M copper and 0.2 M zinc were investigated, and eight metal resistance-related genes (afe-0022, afe-0326, afe-0329, afe-1143, afe-0602, afe-0603, afe-0604, and afe-1788) were sequenced and analyzed. The transcriptional expression levels of eight possible metal tolerance genes in six A. ferrooxidans strains exposed to 0.15 M Cu(2+) and 0.2 M Zn(2+) were determined by real-time quantitative PCR (RT-qPCR), respectively. The copper resistance levels of six A. ferrooxidans strains declined followed by DY26, DX5, DY15, GD-B, GD-0, and YTW. The zinc tolerance levels of six A. ferrooxidans strains exposed to 0.2 M Zn(2+) from high to low were YTW > GD-B > DY26 > GD-0 > DX5 > DY15. Seven metal tolerance-related genes all presented in the genome of six strains, except afe-0604. The metal resistance-related genes showed different transcriptional expression patterns in six A. ferrooxidans strains. The expression of gene afe-0326 and afe-0022 in six A. ferrooxidans strains in response to 0.15 M Cu(2+) showed the same trend with the resistance levels. The expression levels of genes afe-0602, afe-0603, afe-0604, and afe-1788 in six strains response to 0.2 M Zn(2+) did not show a clear correlation between the zinc tolerance levels of six strains. According to the results of RT-qPCR and bioinformatics analysis, the proteins encoded by afe-0022, afe-0326, afe-0329, and afe-1143 were related to Cu(2+) transport of A. ferrooxidans strains. PMID:25023638

  6. Enhancing isobutyric acid production from engineered Acidithiobacillus ferrooxidans cells via media optimization.

    PubMed

    Li, Xiaozheng; West, Alan C; Banta, Scott

    2016-04-01

    The chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans has previously been genetically modified to produce isobutyric acid (IBA) from carbon dioxide while obtaining energy from the oxidation of ferrous iron. Here, a combinatorial approach was used to explore the influence of medium composition in both batch and chemostat cultures in order to improve IBA yields (g IBA/mol Fe(2+)) and productivities (g IBA/L/d). Medium pH, ferrous concentration (Fe(2+)), and inclusion of iron chelators all had positive impact on the IBA yield. In batch experiments, gluconate was found to be a superior iron chelator because its use resulted in smaller excursions in pH. In batch cultures, IBA yields decreased linearly with increases in the final effective Fe(3+) concentrations. Chemostat cultures followed similar trends as observed in batch cultures. Specific cellular productivities were found to be a function of the steady state ORP (Oxidation-reduction potential) of the growth medium, which is primarily determined by the Fe(3+) to Fe(2+) ratio. By operating at low ORP, chemostat cultures were able to achieve volumetric productivities as high as 3.8 ± 0.2 mg IBA/L/d which is a 14-fold increase over the previously reported value. PMID:26370386

  7. Laboratory chalcopyrite oxidation by Acidithiobacillus ferrooxidans: Oxygen and sulfur isotope fractionation

    USGS Publications Warehouse

    Thurston, R.S.; Mandernack, K.W.; Shanks, Wayne C., III

    2010-01-01

    Laboratory experiments were conducted to simulate chalcopyrite oxidation under anaerobic and aerobic conditions in the absence or presence of the bacterium Acidithiobacillus ferrooxidans. Experiments were carried out with 3 different oxygen isotope values of water (??18OH2O) so that approach to equilibrium or steady-state isotope fractionation for different starting conditions could be evaluated. The contribution of dissolved O2 and water-derived oxygen to dissolved sulfate formed by chalcopyrite oxidation was unambiguously resolved during the aerobic experiments. Aerobic oxidation of chalcopyrite showed 93 ?? 1% incorporation of water oxygen into the resulting sulfate during the biological experiments. Anaerobic experiments showed similar percentages of water oxygen incorporation into sulfate, but were more variable. The experiments also allowed determination of sulfate-water oxygen isotope fractionation, ??18OSO4-H2O, of ~ 3.8??? for the anaerobic experiments. Aerobic oxidation produced apparent ??SO4-H2O values (6.4???) higher than the anaerobic experiments, possibly due to additional incorporation of dissolved O2 into sulfate. ??34SSO4 values are ~ 4??? lower than the parent sulfide mineral during anaerobic oxidation of chalcopyrite, with no significant difference between abiotic and biological processes. For the aerobic experiments, a small depletion in ??34SSO4 of ~- 1.5 ?? 0.2??? was observed for the biological experiments. Fewer solids precipitated during oxidation under aerobic conditions than under anaerobic conditions, which may account for the observed differences in sulfur isotope fractionation under these contrasting conditions. ?? 2009 Elsevier B.V.

  8. Are there multiple mechanisms of anaerobic sulfur oxidation with ferric iron in Acidithiobacillus ferrooxidans?

    PubMed

    Kucera, Jiri; Pakostova, Eva; Lochman, Jan; Janiczek, Oldrich; Mandl, Martin

    2016-06-01

    To clarify the pathway of anaerobic sulfur oxidation coupled with dissimilatory ferric iron reduction in Acidithiobacillus ferrooxidans strain CCM 4253 cells, we monitored their energy metabolism gene transcript profiles. Several genes encoding electron transporters involved in aerobic iron and sulfur respiration were induced during anaerobic growth of ferrous iron-grown cells. Most sulfur metabolism genes were either expressed at the basal level or their expression declined. However, transcript levels of genes assumed to be responsible for processing of elemental sulfur and other sulfur intermediates were elevated at the beginning of the growth period. In contrast, genes with predicted functions in formation of hydrogen sulfide and sulfate were significantly repressed. The main proposed mechanism involves: outer membrane protein Cyc2 (assumed to function as a terminal ferric iron reductase); periplasmic electron shuttle rusticyanin; c4-type cytochrome CycA1; the inner membrane cytochrome bc1 complex I; and the quinone pool providing connection to the sulfur metabolism machinery, consisting of heterodisulfide reductase, thiosulfate:quinone oxidoreductase and tetrathionate hydrolase. However, an alternative mechanism seems to involve a high potential iron-sulfur protein Hip, c4-type cytochrome CycA2 and inner membrane cytochrome bc1 complex II. Our results conflict with findings regarding the type strain, indicating strain- or phenotype-dependent pathway variation. PMID:26924114

  9. Crystallization and preliminary X-ray diffraction analysis of tetrathionate hydrolase from Acidithiobacillus ferrooxidans

    PubMed Central

    Kanao, Tadayoshi; Kosaka, Megumi; Yoshida, Kyoya; Nakayama, Hisayuki; Tamada, Taro; Kuroki, Ryota; Yamada, Hidenori; Takada, Jun; Kamimura, Kazuo

    2013-01-01

    Tetrathionate hydrolase (4THase) from the iron- and sulfur-oxidizing bacterium Acidithiobacillus ferrooxidans catalyses the disproportionate hydrolysis of tetrathionate to elemental sulfur, thiosulfate and sulfate. The gene encoding 4THase (Af-tth) was expressed as inclusion bodies in recombinant Escherichia coli. Recombinant Af-Tth was activated by refolding under acidic conditions and was then purified to homogeneity. The recombinant protein was crystallized in 20 mM glycine buffer pH 10 containing 50 mM sodium chloride and 33%(v/v) PEG 1000 using the hanging-drop vapour-diffusion method. The crystal was a hexagonal cylinder with dimensions of 0.2 × 0.05 × 0.05 mm. X-ray crystallographic analysis showed that the crystal diffracted to 2.15 Å resolution and belongs to space group P31 or P32, with unit-cell parameters a = b = 92.1, c = 232.6 Å. PMID:23722856

  10. Identification and characterization of Acidithiobacillus ferrooxidans YY2 and its application in the biodesulfurization of coal.

    PubMed

    Yang, Xinping; Wang, Shimei; Liu, Yujiao; Zhang, Yuanyuan

    2015-01-01

    The acidophilic Fe-oxidizing and S-oxidizing bacterium YY2 was isolated from the acid drainage of a coalmine. Based on morphological and physiological characteristics and phylogenetic analysis, it was identified as Acidithiobacillus ferrooxidans. Significant differences were observed in the oxidation efficiency and cell morphology when YY2 was cultured in 9K medium with ferrous ion (Fe(2+)), elemental sulfur (S(0)), and pyrite as the sole energy source. YY2 exhibited marked Fe(2+) oxidation activity; 44.2 g · L(-1) FeSO4 · 7H2O was completely oxidized in 30 h, but the rates of S(0) and pyrite oxidization were slower. After 20 days, the efficiencies of oxidizing 10 g · L(-1) S(0) and 10 g · L(-1) pyrite were approximately 9.6% and 20%, respectively. Cells cultured in pyrite as substrate secreted more extracellular polymeric substances than they did when cultured in Fe(2+) or S(0). Additionally, 75% total sulfur removal and 86% pyritic sulfur removal was achieved in a sequencing batch reactor of biodesulfurization of coal. PMID:25496139

  11. Biosorption of inorganic and organic arsenic from aqueous solution by Acidithiobacillus ferrooxidans BY-3.

    PubMed

    Yan, Lei; Yin, Huanhuan; Zhang, Shuang; Leng, Feifan; Nan, Wenbin; Li, Hongyu

    2010-06-15

    The traditional techniques for removing low concentration arsenic are unsuitable. The biosorption characteristics of arsenite (iAs(III)) and monomethyl arsonate (MMA(V)) from aqueous solution by Acidithiobacillus ferrooxidans BY-3 (At. f BY-3) were investigated as a function of pH, contact time, initial arsenic concentration, biomass dosage and temperature in this study. Results indicated that Langmuir isotherm model fitted better than Freundlich model to the equilibrium data. Analysis of kinetic data showed that the biosorption processes of both iAs(III) and MMA(V) involved pseudo-second-order kinetics. The thermodynamic parameters such as DeltaG(o), DeltaH(o) and DeltaS(o) of the biosorption process showed that the adsorption of iAs(III) and MMA(V) onto At. f BY-3 was feasible, spontaneous and endothermic under the examined conditions. The competitive biosorption of iAs(III) and MMA(V) in binary mixture system was evaluated, and the results indicated that At. f BY-3 favored MMA(V) biosorption. Fourier-transform infrared spectroscopy (FT-IR) showed -OH and -NH groups were involved in the biosorption process. PMID:20122794

  12. Fate of extracellular polymeric substances of anaerobically digested sewage sludge during pre-dewatering conditioning with Acidithiobacillus ferrooxidans culture.

    PubMed

    Murugesan, Kumarasamy; Ravindran, Balasubramani; Selvam, Ammaiyappan; Kurade, Mayur B; Yu, Shuk-Man; Wong, Jonathan W C

    2016-10-01

    This study investigated the fate of extracellular polymeric substances (EPS) of anaerobically digested saline sewage sludge during its preconditioning. Sludge was conditioned with Acidithiobacillus ferrooxidans (AF) culture for 24h in the presence and absence of Fe(2+) as an energy substrate. pH decreased from 7.24 to 3.12 during sludge conditioning process. The capillary suction time (CST) of conditioned sludge significantly decreased to <10s, and specific resistance to filtration (SRF) was reduced by >94% as compared with control within 4h of conditioning with or without Fe(2+), indicating a significant (P<0.001) improvement in sludge dewaterability. A noticeable decrease in extractable EPS was observed in conditioned sludge. The EPS contents showed a significant negative correlation with dewaterability of sludge (P<0.05). The results suggest that bioacidification treatment using A. ferrooxidans effectively improved sludge dewaterability through modification of sludge EPS. PMID:27040507

  13. Draft genome sequence of the extremely acidophilic biomining bacterium Acidithiobacillus thiooxidans ATCC 19377 provides insights into the evolution of the Acidithiobacillus genus.

    PubMed

    Valdes, Jorge; Ossandon, Francisco; Quatrini, Raquel; Dopson, Mark; Holmes, David S

    2011-12-01

    Acidithiobacillus thiooxidans is a mesophilic, extremely acidophilic, chemolithoautotrophic gammaproteobacterium that derives energy from the oxidation of sulfur and inorganic sulfur compounds. Here we present the draft genome sequence of A. thiooxidans ATCC 19377, which has allowed the identification of genes for survival and colonization of extremely acidic environments. PMID:22123759

  14. [Physiological Properties of Acidithiobacillus ferrooxidans Strains Isolated from Sulfide Ore Deposits in Kazakhstan].

    PubMed

    Kanaeva, Z K; Bulaev, A G; Kanaev, A T; Kondrat'eva, T F

    2015-01-01

    Acidithiobacillus ferroxidans strains were isolated from acidophilic microbial communities of Kazakhstan sulfide ore deposits. Their biotechnologically important properties (optimal and maximal growth temperatures and resistance to NaCl) were determined. While temperature optima of the strains were the same (30-32 degrees C), temperature ranges were different. Thus, strain TFBK oxidized iron very poorly at 37 degrees C, while for strain TFV, the iron oxidation rate at this temperature was insignificantly lower than at lesser temperatures. NaCl inhibited the oxidative activity of both strains. Iron oxidation by strain TFV was inhibited at 5 g/L NaCl and was suppressed almost completely at 20 g/L. Iron oxidation by strain TFBK was inhibited by NaCl to a lesser degree, so that iron oxidation rate was relatively high at 10 g/L, while at 20 g/L NaCl the process was not suppressed completely, although the oxidation rate was low. Sulfur oxidation by these strains was less affected by NaCl than oxidation of ferrous iron. Sulfur oxidation by strain TFV was considerably inhibited only at 20 g/L NaCl, but was not suppressed completely. Sulfur oxidation by strain TFBK was more affected by NaCl. At 10 g/L NaCl the oxidation rate was much lower than at lower NaCl concentrations (sulfate concentrations after 6 days of oxidation at 5 and 10 g/L NaCl were -130 and -100 mM, respectively). While sulfur oxidation by strain TFBK was considerably inhibited at 10 and 20 g/L NaCl, similar to strain TFV it was not suppressed completely. Our results indicate the adaptation of the species A. ferrooxidans to a broad range of growth conditions. PMID:26263692

  15. Construction and Characterization of tetH Overexpression and Knockout Strains of Acidithiobacillus ferrooxidans

    PubMed Central

    Yu, Yangyang; Wang, Huiyan; Li, Xiuting; Lin, Jianqun

    2014-01-01

    Acidithiobacillus ferrooxidans is a major participant in consortia of microorganisms used for bioleaching. It can obtain energy from the oxidation of Fe2+, H2, S0, and various reduced inorganic sulfur compounds (RISCs). Tetrathionate is a key intermediate during RISC oxidation, hydrolyzed by tetrathionate hydrolase (TetH), and used as sole energy source. In this study, a tetH knockout (ΔtetH) mutant and a tetH overexpression strain were constructed and characterized. The tetH overexpression strain grew better on sulfur and tetrathionate and possessed a higher rate of tetrathionate utilization and TetH activity than the wild type. However, its cell yields on tetrathionate were much lower than those on sulfur. The ΔtetH mutant could not grow on tetrathionate but could proliferate on sulfur with a lower cell yield than the wild type's, which indicated that tetrathionate hydrolysis is mediated only by TetH, encoded by tetH. The ΔtetH mutant could survive in ferrous medium with an Fe2+ oxidation rate similar to that of the wild type. For the tetH overexpression strain, the rate was relatively higher than that of the wild type. The reverse transcription-quantitative PCR (qRT-PCR) results showed that tetH and doxD2 acted synergistically, and doxD2 was considered important in thiosulfate metabolism. Of the two sqr genes, AFE_0267 seemed to play as important a role in sulfide oxidation as AFE_1792. This study not only provides a substantial basis for studying the function of the tetH gene but also may serve as a model to clarify other candidate genes involved in sulfur oxidation in this organism. PMID:24727223

  16. Analysis of gene expression provides insights into the mechanism of cadmium tolerance in Acidithiobacillus ferrooxidans.

    PubMed

    Chen, Minjie; Li, Yanjun; Zhang, Li; Wang, Jianying; Zheng, Chunli; Zhang, Xuefeng

    2015-02-01

    Acidithiobacillus ferrooxidans plays a critical role in metal solubilization in the biomining industry, and occupies an ecological niche characterized by high acidity and high concentrations of toxic heavy metal ions. In order to investigate the possible metal resistance mechanism, the cellular distribution of cadmium was tested. The result indicated that Cd(2+) entered the cells upon initial exposure resulting in increased intracellular concentrations, followed by its excretion from the cells during subsequent growth and adaptation. Sequence homology analyses were used to identify 10 genes predicted to participate in heavy metal homeostasis, and the expression of these genes was investigated in cells cultured in the presence of increasing concentrations of toxic divalent cadmium (Cd(2+)). The results suggested that one gene (cmtR A.f ) encoded a putative Cd(2+)/Pb(2+)-responsive transcriptional regulator; four genes (czcA1 A.f , czcA2 A.f , czcB1 A.f ; and czcC1 A.f ) encoded heavy metal efflux proteins for Cd(2+); two genes (cadA1 A.f and cadB1 A.f ) encoded putative cation channel proteins related to the transport of Cd(2+). No significant enhancement of gene expression was observed at low concentrations of Cd(2+) (5 mM) and most of the putative metal resistance genes were up-regulated except cmtR A.f , cadB3 A.f ; and czcB1 A.f at higher concentrations (15 and 30 mM) according to real-time polymerase chain reaction. A model was developed for the mechanism of resistance to cadmium ions based on homology analyses of the predicted genes, the transcription of putative Cd(2+) resistance genes, and previous work. PMID:25344309

  17. Heat and phosphate starvation effects on the proteome, morphology and chemical composition of the biomining bacteria Acidithiobacillus ferrooxidans.

    PubMed

    Ribeiro, Daniela A; Maretto, Danilo A; Nogueira, Fábio C S; Silva, Márcio J; Campos, Francisco A P; Domont, Gilberto B; Poppi, Ronei J; Ottoboni, Laura M M

    2011-06-01

    Acidithiobacillus ferrooxidans is a Gram negative, acidophilic, chemolithoautotrophic bacterium that plays an important role in metal bioleaching. During bioleaching, the cells are subjected to changes in the growth temperature and nutrients starvation. The aim of this study was to gather information about the response of the A.ferrooxidans Brazilian strain LR to K2HPO4 starvation and heat stress through investigation of cellular morphology, chemical composition and differential proteome. The scanning electron microscopic results showed that under the tested stress conditions, A. ferrooxidans cells became elongated while the Fourier transform infrared spectroscopy (FT-IR) analysis showed alterations in the wavenumbers between 850 and 1,275 cm(-1), which are related to carbohydrates, phospholipids and phosphoproteins. These findings indicate that the bacterial cell surface is affected by the tested stress conditions. A proteomic analysis, using 2-DE and tandem mass spectrometry, enabled the identification of 44 differentially expressed protein spots, being 30 due to heat stress (40°C) and 14 due to K2HPO4 starvation. The identified proteins belonged to 11 different functional categories, including protein fate, energy metabolism and cellular processes. The upregulated proteins were mainly from protein fate and energy metabolism categories. The obtained results provide evidences that A. ferrooxidans LR responds to heat stress and K2HPO4 starvation by inducing alterations in cellular morphology and chemical composition of the cell surface. Also, the identification of several proteins involved in protein fate suggests that the bacteria cellular homesostasis was affected. In addition, the identification of proteins from different functional categories indicates that the A. ferrooxidans response to higher than optimal temperatures and phosphate starvation involves global changes in its physiology. PMID:25187146

  18. Reduction of arsenic content in a complex galena concentrate by Acidithiobacillus ferrooxidans

    PubMed Central

    Makita, Mario; Esperón, Margarita; Pereyra, Benito; López, Alejandro; Orrantia, Erasmo

    2004-01-01

    Background Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ferrooxidans. There are a few studies about the benefit of metals of low value through bioleaching. From all of these, there are almost no studies dealing with complex minerals containing arsenopyrite (FeAsS). Reduction and/or elimination of arsenic in these ores increase their value and allows the exploitation of a vast variety of minerals that today are being underexploited. Results Arsenopyrite was totally oxidized. The sum of arsenic remaining in solution and removed by sampling represents from 22 to 33% in weight (yield) of the original content in the mineral. The rest of the biooxidized arsenic form amorphous compounds that precipitate. Galena (PbS) was totally oxidized too, anglesite (PbSO4) formed is virtually insoluble and remains in the solids. The influence of seven factors in a batch process was studied. The maximum rate of arsenic dissolution in the concentrate was found using the following levels of factors: small surface area of particle exposure, low pulp density, injecting air and adding 9 K medium to the system. It was also found that ferric chloride and carbon dioxide decreased the arsenic dissolution rate. Bioleaching kinetic data of arsenic solubilization were used to estimate the dilution rate for a continuous culture. Calculated dilution rates were relatively small (0.088–0.103 day-1). Conclusion Proper conditions of solubilization of arsenic during bioleaching are key features to improve the percentage (22 to 33% in weight) of arsenic removal. Further studies are needed to determine other factors that influence specifically the solubilization of arsenic in

  19. Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

    NASA Astrophysics Data System (ADS)

    Yu, Run-lan; Liu, Jing; Tan, Jian-xi; Zeng, Wei-min; Shi, Li-juan; Gu, Guo-hua; Qin, Wen-qing; Qiu, Guan-zhou

    2014-04-01

    The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleaching. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

  20. Effect of energy source, salt concentration and loading force on colloidal interactions between Acidithiobacillus ferrooxidans cells and mineral surfaces.

    PubMed

    Diao, Mengxue; Nguyen, Tuan A H; Taran, Elena; Mahler, Stephen M; Nguyen, Anh V

    2015-08-01

    The surface appendages and extracellular polymeric substances of cells play an important role in the bacterial adhesion process. In this work, colloidal forces and nanomechanical properties of Acidithiobacillus ferrooxidans (A. f) interacted with silicon wafer and pyrite (FeS2) surfaces in solutions of varying salt concentrations were quantitatively examined using the bacterial probe technique with atomic force microscopy. A. f cells were cultured with either ferrous sulfate or elemental sulfur as key energy sources. Our results show that A. f cells grown with ferrous ion and elemental sulfur exhibit distinctive retraction force vs separation distance curves with stair-step and saw tooth shapes, respectively. During the approach of bacterial probes to the substrate surfaces, surface appendages and biopolymers of cells are sequentially compressed. The conformations of surface appendages and biopolymers are significantly influenced by the salt concentrations. PMID:26057245

  1. Erratum to “Proteomic analysis of differential protein expression in Acidithiobacillus ferrooxidans cultivated in high potassium concentration” [Microbiol. Res. 168 (7) (2013) 455–460].

    PubMed

    Ouyang, Jianping; Guo, Wenbin; Li, Bo; Gu, Li; Zhang, Huijun; Xinhua Chen, Huijun

    2016-01-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic acidophile that oxidizes ferrous iron or sulfur compounds to obtain energy in the presence of various ions. To investigate the potassium ion response of A. ferrooxidans, we conducted a proteomics analysis. We identified eight proteins that were differentially expressed in the presence of high potassium concentration, including four up-regulated and four down-regulated proteins. Transcription levels of the genes encoding differential expressed proteins were subsequently analyzed by Northern blot in the presence of high potassium concentration. Among the up-regulated proteins, GDP-mannose 4,6-dehydratase, ribose 5-phosphate isomerase A and ribose-phosphate pyrophosphokinase were known to be implicated in the synthesis of glycocalyx, suggesting that the formation of glycocalyx might be involved in the A. ferrooxidans response to high potassium concentration. Thickening of the glycocalyx layer was also observed in cells cultivated under high potassium concentration via transmission electronic microscopy (TEM) analysis. Among the down-regulated proteins, ATP synthase F1 delta subunit and ATP synthase F1 beta subunit were two important components of ATP synthase. ATP synthase (P-ATPase) is directly linked to the transport of potassium into the cell, thus Acidithiobacillus ferrooxidans might just reduce the quantity of ATP synthase to offset the high potassium level in the culture medium. Therefore, the results obtained here provide some new clues to improve our understanding of the response of A. ferrooxidans to high potassium concentration. PMID:27062771

  2. Involvement of sulfide:quinone oxidoreductase in sulfur oxidation of an acidophilic iron-oxidizing bacterium, Acidithiobacillus ferrooxidans NASF-1.

    PubMed

    Wakai, Satoshi; Kikumoto, Mei; Kanao, Tadayoshi; Kamimura, Kazuo

    2004-12-01

    The effects of cyanide, azide, and 2-n-Heptyl-4-hydroxy-quinoline-N-oxide (HQNO) on the oxidation of ferrous ion or elemental sulfur with Acidithiobacillus ferrooxidans NASF-1 cells grown in iron- or sulfur-medium were examined. The iron oxidation of both iron- and sulfur-grown cells was strongly inhibited by cyanide and azide, but not by HQNO. Sulfur oxidation was relatively resistant to cyanide and azide, and inhibited by HQNO. Higher sulfide oxidation, ubiquinol dehydrogenase activity, and sulfide:quinone oxidoreductase (SQR) activity were observed in sulfur-grown cells more than in iron-grown cells. Sulfide oxidation in the presence of ubiquinone with the membrane fraction was inhibited by HQNO, but not by cyanide, azide, antimycin A, and myxothiazol. The transcription of three genes, encoding an aa(3)-type cytochrome c oxidase (coxB), a bd-type ubiquinol oxidase (cydA), and an sqr, were measured by real-time reverse transcription polymerase chain reaction. The transcriptional levels of coxB and cydA genes were similar in sulfur- and iron-grown cells, but that of sqr was 3-fold higher in sulfur-grown cells than in iron-grown cells. A model is proposed for the oxidation of reduced inorganic sulfur compounds in A. ferrooxidans NASF-1 cells. PMID:15618623

  3. Purification and biochemical characterization of the F1-ATPase from Acidithiobacillus ferrooxidans NASF-1 and analysis of the atp operon.

    PubMed

    Wakai, Satoshi; Ohmori, Asami; Kanao, Tadayoshi; Sugio, Tsuyoshi; Kamimura, Kazuo

    2005-10-01

    ATPase was purified 51-fold from a chemoautotrophic, obligately acidophilic iron-oxidizing bacterium, Acidithiobacillus ferrooxidans NASF-1. The purified ATPase showed the typical subunit pattern of the F1-ATPase on a polyacrylamide gel containing sodium dodecyl sulfate, with 5 subunits of apparent molecular masses of 55, 50, 33, 20, and 18 kDa. The enzyme hydrolyzed ATP, GTP, and ITP, but neither UTP nor ADP. The K(m) value for ATP was 1.8 mM. ATPase activity was optimum at pH 8.5 at 45 degrees C, and was activated by sulfite. Azide strongly inhibited the enzyme activity, whereas the enzyme was relatively resistant to vanadate, nitrate, and N,N'-dicyclohexylcarbodiimide. The genes encoding the subunits for the F1F(O)-ATPase from A. ferrooxidans NASF-1 were cloned as three overlapping fragments by PCR cloning and sequenced. The molecular masses of the alpha, beta, gamma, delta, and epsilon subunits of the F1 portion were deduced from the amino acid sequences to be 55.5, 50.5, 33.1, 19.2, and 15.1 kDa, respectively. PMID:16244438

  4. Impact of bioavailable Pb2+ on Fe2+ oxidation in the presence of a mixed culture of Acidithiobacillus ferrooxidans

    NASA Astrophysics Data System (ADS)

    Wang, H.; Yang, X.; Gong, L.; Jiang, Z.

    2009-12-01

    Numerous investigations were conducted on the effects of a variety of metals, including As, Cu, Zn, Cr on the growth of Acidithiobacillus ferrooxidans (an iron oxidizer and indigenous to acidic environment) and Fe2+ oxidation. However, less work was reported concerning the Pb2+ effect due to its quick precipitation as anglesite in SO42--rich solutions. The reported inhibiting concentrations of Pb2+ varied greatly on the oxidizing rate of ferrous in the presence of A. ferrooxidans, and the reasons remain unclear. Comparative studies were conducted between chemical and microbial oxidation of ferrous by a mixed culture of A. ferrooxidans in the presence of different concentration of Pb2+. Eh, pH and Fe2+ concentration were monitored periodically and the final precipitates were analyzed by X-ray diffraction (XRD), scanning electronic microscopy (SEM), and SEM-EDAX (Energy-dispersive X-ray spectroscopy). To check the impact of bioavailable Pb2+ on Fe2+ oxidation, initial precipitation was removed before the microbial inoculation. Our data showed that Pb2+ will exert a remarkable inhibition on microbial oxidation of ferrous when initial Pb2+ concentration reached as high as 5 g/L. However, the bioavailable Pb2+ in this case should be much lower than 5 g/L in the solution due to the precipitation of anglesite (The absolute concentration was under analysis). The threshold of Pb2+ concentrations to inhibit the microbial oxidation varies among the previous studies. This might result from the different microbial strains used or the mistaking of initial concentration as the substantial concentration of bioavailable Pb2+ after precipitation as anglesite. In contrast, Pb2+ does not show any obvious influence on chemical oxidation of ferrous. XRD spectrum of the final precipitates showed that anglesite was the only solid phase detected in chemical systems, while pure jarosite was found in the microbial systems. No lead was detected in jarosite by SEM-EDAX, inferring that Pb was

  5. Reconstitution of Iron Oxidase from Sulfur-Grown Acidithiobacillus ferrooxidans▿ †

    PubMed Central

    Taha, Taher M.; Kanao, Tadayoshi; Takeuchi, Fumiaki; Sugio, Tsuyoshi

    2008-01-01

    The iron oxidation system from sulfur-grown Acidithiobacillus ferrooxidans ATCC 23270 cells was reconstituted in vitro. Purified rusticyanin, cytochrome c, and aa3-type cytochrome oxidase were essential for reconstitution. The iron-oxidizing activity of the reconstituted system was 3.3-fold higher than that of the cell extract from which these components were purified. PMID:18791023

  6. Interplay Between Expression of Sulfur Assimilation Pathway Genes and Zn(2+) and Pb(2+) Stress in Acidithiobacillus ferrooxidans.

    PubMed

    Zheng, Chunli; Chen, Minjie; Wang, Dan; Zhang, Li; Wang, JianYing; Zhang, Xuefeng

    2016-10-01

    We have previously demonstrated that in Acidithiobacillus ferrooxidans, resistance to the highly toxic divalent cation Cd(2+) is mediated in part by the sulfur assimilation pathway (SAP) and enhanced intracellular concentrations of cysteine and glutathione(GSH) (Zheng et al., Extremophiles 19:429-436, 2015). In this paper, we investigate the interplay between Zn(2+) and Pb(2+) resistances, SAP gene expression, and thiol-containing metabolite levels. Cells grown in the presence of 300 mM Zn(2+) had enhanced activities of the following enzymes: adenosylphosphosulphate reductase (APR, 40-fold), serine acetyltransferase (SAT, 180-fold), and O-acetylserine (thiol) lyase (OAS-TL, 230-fold). We investigated the concentrations of mRNA transcripts of the genes encoding these enzymes in cells grown in the presence of 600 mM Zn(2+): transcripts for 4 SAP genes-ATPS(ATP sulphurylase), APR, SiR(sulfite reductase), SAT, and OAS-TL-each showed a more than three-fold increase in concentration. At the metabolite level, concentrations of intracellular cysteine and glutathione (GSH) were nearly doubled. When cells were grown in the presence of 10 mM Pb(2+), SAP gene transcript concentrations, cysteine, and GSH concentrations were all decreased, as were SAP enzyme activities. These results suggested that Zn(2+) induced SAP pathway gene transcription, while Pb(2+) inhibited SAP gene expression and enzyme activities compared to the pathway in most organisms. Because of the detoxification function of thiol pool, the results also suggested that the high resistance of A. ferrooxidans to Zn(2+) may also be due to regulation of GSH and the cysteine synthesis pathway. PMID:27376536

  7. Attachment of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum cultured under varying conditions to pyrite, chalcopyrite, low-grade ore and quartz in a packed column reactor.

    PubMed

    Africa, Cindy-Jade; van Hille, Robert P; Harrison, Susan T L

    2013-02-01

    The attachment of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum spp. grown on ferrous medium or adapted to a pyrite mineral concentrate to four mineral substrata, namely, chalcopyrite and pyrite concentrates, a low-grade chalcopyrite ore (0.5 wt%) and quartzite, was investigated. The quartzite represented a typical gangue mineral and served as a control. The attachment studies were carried out in a novel particle-coated column reactor. The saturated reactor containing glass beads, which were coated with fine mineral concentrates, provided a quantifiable surface area of mineral concentrate and maintained good fluid flow. A. ferrooxidans and Leptospirillum spp. had similar attachment characteristics. Enhanced attachment efficiency occurred with bacteria grown on sulphide minerals relative to those grown on ferrous sulphate in an ore-free environment. Selective attachment to sulphide minerals relative to gangue materials occurred, with mineral adapted cultures attaching to the minerals more efficiently than ferrous grown cultures. Mineral-adapted cultures showed highest levels of attachment to pyrite (74% and 79% attachment for A. ferrooxidans and L. ferriphilum, respectively). This was followed by attachment of mineral-adapted cultures to chalcopyrite (63% and 58% for A. ferrooxidans and L. ferriphilum, respectively). A. ferrooxidans and L. ferriphilum exhibited lower levels of attachment to low-grade ore and quartz relative to the sulphide minerals. PMID:22410741

  8. [Dependence of the genotypic characteristics of Acidithiobacillus ferrooxidans on the physical, chemical, and electrophysical properties of pyrites].

    PubMed

    Tupikina, O V; Kondrat'eva, T F; Karavaĭko, G I

    2005-01-01

    This study focused on the effect of physical, chemical, and electrophysical properties of two pyrites, pyrite 1, which had hole-type (p-type) conductivity, and pyrite 2, with electron-type (n-type) conductivity, on the genotypic characteristics of Acidithiobacillus ferrooxidans strains TFV-1 and TFBk, which were isolated from different substrates. After the adaptation of the strains to the pyrites at a pulp density of 1%, pulsed-field electrophoresis revealed changes in the chromosomal DNA of strain TFV-1 adapted to pyrite 1 and strain TFBk adapted to either of the pyrite types. In pyrite-adapted strain TFBk, the plasmid composition was the same as after growth on a medium containing ferrous iron, whereas, in strain TFV-1, changes in plasmid sizes or both in plasmid sizes and plasmid number occurred. After an increase in the density of the pyrite 2 pulp from 1 to 10%, the plasmid number increased from three to four, and, after an increase in the density of the pyrite 1 pulp from 1 to 7%, the plasmid number increased from two to six. PMID:16315978

  9. Effects of pyrite bioleaching solution of Acidithiobacillus ferrooxidans on viability, differentiation and mineralization potentials of rat osteoblasts.

    PubMed

    Zhou, Jian; Chen, Ke-Ming; Zhi, De-Juan; Xie, Qin-Jian; Xian, Cory J; Li, Hong-Yu

    2015-12-01

    Iron pyrite, an important component of traditional Chinese medicine, has a poor solubility, bioavailability, and patient compliance due to a high dose required and associated side effects, all of which have limited its clinical applications and experimental studies on its action mechanisms in improving fracture healing. This study investigated Acidithiobacillus ferrooxidans (A.f)-bioleaching of two kinds of pyrites and examined bioactivities of the derived solutions in viability and osteogenic differentiation in rat calvarial osteoblasts. A.f bioleaching improved element contents (Fe, Mn, Zn, Cu, and Se) in the derived solutions and the solutions concentration-dependently affected osteoblast viability and differentiation. While the solutions had no effects at low concentrations and inhibited the osteoblast alkaline phosphatase (ALP) activity at high concentrations, they improved ALP activity at their optimal concentrations. The improved osteoblast differentiation and osteogenic function at optimal concentrations were also revealed by levels of ALP cytochemical staining, calcium deposition, numbers and areas of mineralized nodules formed, mRNA and protein expression levels of osteogenesis-related genes (osteocalcin, Bmp-2, Runx-2, and IGF-1), and Runx-2 nuclear translocation. Data from this study will be useful in offering new strategies for improving pyrite bioavailability and providing a mechanistic explanation for the beneficial effects of pyrite in improving bone healing. PMID:26283321

  10. [Dependence of the genotypic characteristics of Acidithiobacillus ferrooxidans on the physical, chemical, and electrophysical properties of pyrites].

    PubMed

    Tupikina, O V; Kondrat'eva, T F; Samorukova, V D; Rassulov, V A; Karavaĭko, G I

    2005-01-01

    Comparison of Acidithiobacillus ferrooxidans strains TFV-1 and TFBk with respect to their capacity to oxidize pyrite 1, with hole-type (p-type) conductivity, or pyrite 2, with an electron-type (n-type) conductivity, showed that, at a pulp density of 1%, both before and after its adaptation to the pyrites, strain TFBk, isolated from a substrate with a more complex mineral composition, grew faster and oxidized the pyrites of both conductivity types more efficiently than strain TFV-1, which was isolated from a mineralogically simple ore. At a pulp density of 3-5%, the oxidation of pyrite 1 by strain TFV-1 and both of the pyrites by strain TFBk began only after an artificial increase in Eh to 600 mV. If the pulp density was increased gradually, strain TFBk could oxidize the pyrites at its higher values than strain TFV-1, with the rate of pyrite 2 oxidation being higher than that of pyrite 1. During chemical oxidation of both of the pyrites, an increase was observed in the absolute values of the coefficients of thermoelectromotive force (KTEMF); during bacterial-chemical oxidation, the KTEMF of pyrite 1 changed insignificantly, whereas the KTEMF of pyrite 2 decreased. PMID:16315977

  11. The quinone-binding site of Acidithiobacillus ferrooxidans sulfide: quinone oxidoreductase controls both sulfide oxidation and quinone reduction.

    PubMed

    Zhang, Yanfei; Qadri, Ali; Weiner, Joel H

    2016-04-01

    Sulfide:quinone oxidoreductase (SQR) is a peripheral membrane enzyme that catalyzes the oxidation of sulfide and the reduction of ubiquinone. Ubiquinone binds to a conserved hydrophobic domain and shuttles electrons from a noncovalent flavin adenine dinucleotide cofactor to the membrane-bound quinone pool. Utilizing the structure of decylubiquinone bound to Acidithiobacillus ferrooxidans SQR, we combined site-directed mutagenesis and kinetic approaches to analyze quinone binding. SQR can reduce both benzoquinones and naphthoquinones. The alkyl side-chain of ubiquinone derivatives enhances binding to SQR but limits the enzyme turnover. Pentachlorophenol and 2-n-heptyl-4-hydroxyquinoline-N-oxide are potent inhibitors of SQR with apparent inhibition constants (Ki) of 0.46 μmol·L(-1) and 0.58 μmol·L(-1), respectively. The highly conserved amino acids surrounding the quinone binding site play an important role in quinone reduction. The phenyl side-chains of Phe357 and Phe391 sandwich the benzoquinone head group and are critical for quinone binding. Importantly, conserved amino acids that define the ubiquinone-binding site also play an important role in sulfide oxidation/flavin reduction. PMID:26914540

  12. Pyrite Oxidation under initially neutral pH conditions and in the presence of Acidithiobacillus ferrooxidans and micromolar hydrogen peroxide

    NASA Astrophysics Data System (ADS)

    Ma, Y.; Lin, C.

    2012-01-01

    Hydrogen peroxide (H2O2) at a micromolar level played a role in the microbial surface oxidation of pyrite crystals under initially neutral pH. When the mineral-bacteria system was cyclically exposed to 50 μM H2O2, the colonization of Acidithiobacillus ferrooxidans onto the mineral surface was markedly enhanced, as compared to the control (no added H2O2). This can be attributed to the effects of H2O2 on increasing the roughness of the mineral surfaces, as well as the acidity and Fe2+ concentration at the mineral-solution interfaces. All of these effects tended to create more favourable nano- to micro-scale environments in the mineral surfaces for the cell adsorption. However, higher H2O2 levels inhibited the attachment of cells onto the mineral surfaces, possibly due to the oxidative stress in the bacteria when they approached the mineral surfaces where high levels of free radicals are present as a result of Fenton-like reactions. The more aggressive nature of H2O2 as an oxidant caused marked surface flaking of the mineral surface. The XPS results suggest that H2O2 accelerated the oxidation of pyrite-S and consequently facilitated the overall corrosion cycle of pyrite surfaces. This was accompanied by pH drop in the solution in contact with the pyrite cubes.

  13. Mineral respiration under extreme acidic conditions: from a supramolecular organization to a molecular adaptation in Acidithiobacillus ferrooxidans.

    PubMed

    Roger, Magali; Castelle, Cindy; Guiral, Marianne; Infossi, Pascale; Lojou, Elisabeth; Giudici-Orticoni, Marie-Thérèse; Ilbert, Marianne

    2012-12-01

    Acidithiobacillus ferrooxidans is an acidophilic chemolithoautotrophic Gram-negative bacterium that can derive energy from the oxidation of ferrous iron at pH 2 using oxygen as electron acceptor. The study of this bacterium has economic and fundamental biological interest because of its use in the industrial extraction of copper and uranium from ores. For this reason, its respiratory chain has been analysed in detail in recent years. Studies have shown the presence of a functional supercomplex that spans the outer and the inner membranes and allows a direct electron transfer from the extracellular Fe2+ ions to the inner membrane cytochrome c oxidase. Iron induces the expression of two operons encoding proteins implicated in this complex as well as in the regeneration of the reducing power. Most of these are metalloproteins that have been characterized biochemically, structurally and biophysically. For some of them, the molecular basis of their adaptation to the periplasmic acidic environment has been described. Modifications in the metal surroundings have been highlighted for cytochrome c and rusticyanin, whereas, for the cytochrome c oxidase, an additional partner that maintains its stability and activity has been demonstrated recently. PMID:23176476

  14. Synchrotron radiation based STXM analysis and micro-XRF mapping of differential expression of extracellular thiol groups by Acidithiobacillus ferrooxidans grown on Fe(2+) and S(0).

    PubMed

    Xia, Jin-Lan; Liu, Hong-Chang; Nie, Zhen-Yuan; Peng, An-An; Zhen, Xiang-Jun; Yang, Yun; Zhang, Xiu-Li

    2013-09-01

    The differential expression of extracellular thiol groups by Acidithiobacillus ferrooxidans grown on substrates Fe(2+) and S(0) was investigated by using synchrotron radiation based scanning transmission X-ray microscopy (STXM) imaging and microbeam X-ray fluorescence (μ-XRF) mapping. The extracellular thiol groups (SH) were first alkylated by iodoacetic acid forming Protein-SCH2COOH and then the P-SCH2COOH was marked by calcium ions forming P-SCH2COOCa. The STXM imaging and μ-XRF mapping of SH were based on analysis of SCH2COO-bonded Ca(2+). The results indicated that the thiol group content of A. ferrooxidans grown on S(0) is 3.88 times to that on Fe(2+). Combined with selective labeling of SH by Ca(2+), the STXM imaging and μ-XRF mapping provided an in situ and rapid analysis of differential expression of extracellular thiol groups. PMID:23850802

  15. Synthesis and properties of ternary (K, NH₄, H₃O)-jarosites precipitated from Acidithiobacillus ferrooxidans cultures in simulated bioleaching solutions.

    PubMed

    Jones, F Sandy; Bigham, Jerry M; Gramp, Jonathan P; Tuovinen, Olli H

    2014-11-01

    The purpose of this study was to synthesize a series of solid solution jarosites by biological oxidation of ferrous iron at pH2.2-4.4 and ambient temperature in media containing mixtures of K(+) (0, 1, 4, 6, 12, 31 mM) and NH4(+) (6.1, 80, 160, 320 mM). The starting material was a liquid medium for Acidithiobacillus ferrooxidans comprised of 120 mM FeSO4 solution and mineral salts at pH2.2. Following inoculation with A. ferrooxidans, the cultures were incubated in shake flasks at 22°C. As bacteria oxidized ferrous iron, ferric iron hydrolyzed and precipitated as jarosite-group minerals (AFe3(SO4)2(OH)6) and/or schwertmannite (idealized formula Fe8O8(OH)6(SO4)·nH2O). The precipitates were characterized by X-ray diffraction (XRD), elemental analysis, and Munsell color. Schwertmannite was the dominant mineral product at low combinations of K(+) (≤ 4 mM) and NH4(+) (≤ 80 mM) in the media. At higher single or combined concentrations, yellowish jarosite phases were produced, and Munsell hue provided a sensitive means of detecting minor schwertmannite in the oxidation products. Although the hydrated ionic radii of K(+) and NH4(+) are similar, K(+) greatly facilitated the formation of a jarosite phase compared to NH4(+). Unit cell and cell volume calculations from refinements of the powder XRD patterns indicated that the jarosite phases produced were mostly ternary (K, NH4, H3O)-solid solutions that were also deficient in structural Fe, especially at low NH4 contents. Thus, ferric iron precipitation from the simulated bioleaching systems yielded solid solutions of jarosite with chemical compositions that were dependent on the relative concentrations of K(+) and NH4(+) in the synthesis media. No phase separations involving discrete, end-member K-jarosite or NH4-jarosite were detected in the un-aged precipitates. PMID:25280720

  16. The Multicenter Aerobic Iron Respiratory Chain of Acidithiobacillus ferrooxidans Functions as an Ensemble with a Single Macroscopic Rate Constant.

    PubMed

    Li, Ting-Feng; Painter, Richard G; Ban, Bhupal; Blake, Robert C

    2015-07-24

    Electron transfer reactions among three prominent colored proteins in intact cells of Acidithiobacillus ferrooxidans were monitored using an integrating cavity absorption meter that permitted the acquisition of accurate absorbance data in suspensions of cells that scattered light. The concentrations of proteins in the periplasmic space were estimated to be 350 and 25 mg/ml for rusticyanin and cytochrome c, respectively; cytochrome a was present as one molecule for every 91 nm(2) in the cytoplasmic membrane. All three proteins were rapidly reduced to the same relative extent when suspensions of live bacteria were mixed with different concentrations of ferrous ions at pH 1.5. The subsequent molecular oxygen-dependent oxidation of the multicenter respiratory chain occurred with a single macroscopic rate constant, regardless of the proteins' in vitro redox potentials or their putative positions in the aerobic iron respiratory chain. The crowded electron transport proteins in the periplasm of the organism constituted an electron conductive medium where the network of protein interactions functioned in a concerted fashion as a single ensemble with a standard reduction potential of 650 mV. The appearance of product ferric ions was correlated with the reduction levels of the periplasmic electron transfer proteins; the limiting first-order catalytic rate constant for aerobic respiration on iron was 7,400 s(-1). The ability to conduct direct spectrophotometric studies under noninvasive physiological conditions represents a new and powerful approach to examine the extent and rates of biological events in situ without disrupting the complexity of the live cellular environment. PMID:26041781

  17. Effect of uncouplers on endogenous respiration and ferrous iron oxidation in a chemolithoautotrophic bacterium Acidithiobacillus (Thiobacillus) ferrooxidans.

    PubMed

    Chen, Yongqiang; Suzuki, Isamu

    2004-08-01

    Oxidation of ferrous iron (Fe2+) to ferric iron (Fe3+) with oxygen (O2) by Acidithiobacillus (Thiobacillus) ferrooxidans is considered to be inhibited by uncouplers. Oxidation of the endogenous substrates (presumably NADH) with O2 or Fe3+, on the other hand, was stimulated by uncouplers, 2,4-dinitrophenol (DNP) and carbonylcyanide-m-chlorophenyl-hydrazone (CCCP), as expected in respiratorily controlled mitochondria or heterotrophic bacteria. Amytal and rotenone were inhibitory. Fe3+ reduction by endogenous substrates was studied extensively and was found to be stimulated by a permeable anion, SCN- and weak acids, as well as the above uncouplers. Proton translocating properties of some of these stimulators were shown by following a pH change in the cell suspension. It was concluded that any compounds that destroy proton electrochemical gradient, Deltap, stimulated endogenous respiration. Stimulation of Fe2+ or ascorbate oxidation by lower concentrations of uncouplers was successfully demonstrated by shortening the reaction time, but only to a small extent. Uncouplers at concentrations stimulatory to endogenous respiration inhibited Fe2+ oxidation if present before Fe2+ addition. The inhibition by 10 microM CCCP was reversed by washing the cells in a buffer. Complex I inhibitors, atabrine, rotenone and amytal inhibited Fe2+ oxidation, more strongly in the presence of 0.1 mM DNP. It is proposed that Fe2+ oxidation required Deltap perhaps to climb an energetically uphill reaction or to reduce NAD+ to NADH by reversed electron flow for CO2 fixation. The latter interpretation implies some obligatory coupling between Fe2+ oxidation and NAD+ reduction. PMID:15268949

  18. The Multicenter Aerobic Iron Respiratory Chain of Acidithiobacillus ferrooxidans Functions as an Ensemble with a Single Macroscopic Rate Constant*

    PubMed Central

    Li, Ting-Feng; Painter, Richard G.; Ban, Bhupal; Blake, Robert C.

    2015-01-01

    Electron transfer reactions among three prominent colored proteins in intact cells of Acidithiobacillus ferrooxidans were monitored using an integrating cavity absorption meter that permitted the acquisition of accurate absorbance data in suspensions of cells that scattered light. The concentrations of proteins in the periplasmic space were estimated to be 350 and 25 mg/ml for rusticyanin and cytochrome c, respectively; cytochrome a was present as one molecule for every 91 nm2 in the cytoplasmic membrane. All three proteins were rapidly reduced to the same relative extent when suspensions of live bacteria were mixed with different concentrations of ferrous ions at pH 1.5. The subsequent molecular oxygen-dependent oxidation of the multicenter respiratory chain occurred with a single macroscopic rate constant, regardless of the proteins' in vitro redox potentials or their putative positions in the aerobic iron respiratory chain. The crowded electron transport proteins in the periplasm of the organism constituted an electron conductive medium where the network of protein interactions functioned in a concerted fashion as a single ensemble with a standard reduction potential of 650 mV. The appearance of product ferric ions was correlated with the reduction levels of the periplasmic electron transfer proteins; the limiting first-order catalytic rate constant for aerobic respiration on iron was 7,400 s−1. The ability to conduct direct spectrophotometric studies under noninvasive physiological conditions represents a new and powerful approach to examine the extent and rates of biological events in situ without disrupting the complexity of the live cellular environment. PMID:26041781

  19. Quantitative X-ray photoelectron spectroscopy-based depth profiling of bioleached arsenopyrite surface by Acidithiobacillus ferrooxidans

    NASA Astrophysics Data System (ADS)

    Zhu, Tingting; Lu, Xiancai; Liu, Huan; Li, Juan; Zhu, Xiangyu; Lu, Jianjun; Wang, Rucheng

    2014-02-01

    In supergene environments, microbial activities significantly enhance sulfide oxidation and result in the release of heavy metals, causing serious contamination of soils and waters. As the most commonly encountered arsenic mineral in nature, arsenopyrite (FeAsS) accounts for arsenic contaminants in various environments. In order to investigate the geochemical behavior of arsenic during microbial oxidation of arsenopyrite, (2 3 0) surfaces of arsenopyrite slices were characterized after acidic (pH 2.00) and oxidative decomposition with or without an acidophilic microorganism Acidithiobacillus ferrooxidans. The morphology as well as chemical and elemental depth profiles of the oxidized arsenopyrite surface were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. With the mediation of bacteria, cell-shaped and acicular pits were observed on the reacted arsenopyrite surface, and the concentration of released arsenic species in solution was 50 times as high as that of the abiotic reaction after 10 days reaction. Fine-scale XPS depth profiles of the reacted arsenopyrite surfaces after both microbial and abiotic oxidation provided insights into the changes in chemical states of the elements in arsenopyrite surface layers. Within the 450 nm surface layer of abiotically oxidized arsenopyrite, Fe(III)-oxides appeared and gradually increased towards the surface, and detectable sulfite and monovalent arsenic appeared above 50 nm. In comparison, higher contents of ferric sulfate, sulfite, and arsenite were found in the surface layer of approximately 3 μm of the microbially oxidized arsenopyrite. Intermediates, such as Fe(III)-AsS and S0, were detectable in the presence of bacteria. Changes of oxidative species derived from XPS depth profiles show the oxidation sequence is Fe > As = S in abiotic oxidation, and Fe > S > As in microbial oxidation. Based on these results, a possible reaction path of microbial oxidation was proposed in a concept model.

  20. Isolation, sequence analysis, and comparison of two plasmids (28 and 29 kilobases) from the biomining bacterium Leptospirillum ferrooxidans ATCC 49879.

    PubMed

    Coram, Nicolette J; van Zyl, Leonardo J; Rawlings, Douglas E

    2005-11-01

    Two plasmids, of 28,878 bp and 28,012 bp, were isolated from Leptospirillum ferrooxidans ATCC 49879. Altogether, a total of 67 open reading frames (ORFs) were identified on both plasmids, of which 32 had predicted products with high homology to proteins of known function, while 11 ORFs had predicted products with homology to previously identified proteins of unknown function. Twenty-four ORFs had products with no homologues in the GenBank/NCBI database. An analysis of the ORFs and other features of the two plasmids, the first to be isolated from a bacterium of the genus Leptospirillum, is presented. PMID:16269793

  1. A New Iron-oxidizing/O2-reducing Supercomplex Spanning Both Inner and Outer Membranes, Isolated from the Extreme Acidophile Acidithiobacillus ferrooxidans*

    PubMed Central

    Castelle, Cindy; Guiral, Marianne; Malarte, Guillaume; Ledgham, Fouzia; Leroy, Gisèle; Brugna, Myriam; Giudici-Orticoni, Marie-Thérèse

    2008-01-01

    The iron respiratory chain of the acidophilic bacterium Acidithiobacillus ferrooxidans involves various metalloenzymes. Here we demonstrate that the oxygen reduction pathway from ferrous iron (named downhill pathway) is organized as a supercomplex constituted of proteins located in the outer and inner membranes as well as in the periplasm. For the first time, the outer membrane-bound cytochrome c Cyc2 was purified, and we showed that it is responsible for iron oxidation and determined that its redox potential is the highest measured to date for a cytochrome c. The organization of metalloproteins inside the supramolecular structure was specified by protein-protein interaction experiments. The isolated complex spanning the two membranes had iron oxidase as well as oxygen reductase activities, indicating functional electron transfer between the first iron electron acceptor, Cyc2, and the CuA center of cytochrome c oxidase aa3. This is the first characterization of a respirasome from an acidophilic bacterium. In Acidithiobacillus ferrooxidans,O2 reduction from ferrous iron must be coupled to the energy-consuming reduction of NAD+(P) from ferrous iron (uphill pathway) required for CO2 fixation and other anabolic processes. Besides the proteins involved in the O2 reduction, there were additional proteins in the supercomplex, involved in uphill pathway (bc complex and cytochrome Cyc42), suggesting a possible physical link between these two pathways. PMID:18632666

  2. The use of (5Z)-4-bromo-5-(bromomethylene)-2(5H)-furanone for controlling acid mine drainage through the inhibition of Acidithiobacillus ferrooxidans biofilm formation.

    PubMed

    Zhao, Yang; Chen, Peng; Nan, Wenbin; Zhi, Dejuan; Liu, Ronghui; Li, Hongyu

    2015-06-01

    The aim of this study was to determine whether acid mine drainage (AMD) production can be decreased by (5Z)-4-bromo-5-(bromomethylene)-2(5H)-furanone (furanone C-30) in the presence of Acidithiobacillus ferrooxidans (A. ferrooxidans). The effects of furanone C-30 on A. ferrooxidans biofilm production were determined by crystal violet staining and confocal laser scanning microscopy (CLSM). Biofilm-related gene expression was investigated using real-time RT-PCR. Finally, the effects of furanone C-30 on AMD production were evaluated. The results show that furanone C-30 inhibits the production of extracellular polymeric substances (EPS) and biofilm formation and significantly down-regulates the expression of biofilm-related genes. The decreased EPS production led to reduced pentlandite attachment and biofilm formation on pentlandite. Furthermore, the dissolution of both nickel and copper were inhibited by furanone C-30 without new acid formation. This study provides a promising biochemical method to control AMD. PMID:25802048

  3. Ferrous iron oxidation by sulfur-oxidizing Acidithiobacillus ferrooxidans and analysis of the process at the levels of transcription and protein synthesis.

    PubMed

    Kucera, Jiri; Bouchal, Pavel; Lochman, Jan; Potesil, David; Janiczek, Oldrich; Zdrahal, Zbynek; Mandl, Martin

    2013-04-01

    In contrast to iron-oxidizing Acidithiobacillus ferrooxidans, A. ferrooxidans from a stationary phase elemental sulfur-oxidizing culture exhibited a lag phase in pyrite oxidation, which is similar to its behaviour during ferrous iron oxidation. The ability of elemental sulfur-oxidizing A. ferrooxidans to immediately oxidize ferrous iron or pyrite without a lag phase was only observed in bacteria obtained from growing cultures with elemental sulfur. However, these cultures that shifted to ferrous iron oxidation showed a low rate of ferrous iron oxidation while no growth was observed. Two-dimensional gel electrophoresis was used for a quantitative proteomic analysis of the adaptation process when bacteria were switched from elemental sulfur to ferrous iron. A comparison of total cell lysates revealed 39 proteins whose increase or decrease in abundance was related to this phenotypic switching. However, only a few proteins were closely related to iron and sulfur metabolism. Reverse-transcription quantitative PCR was used to further characterize the bacterial adaptation process. The expression profiles of selected genes primarily involved in the ferrous iron oxidation indicated that phenotypic switching is a complex process that includes the activation of genes encoding a membrane protein, maturation proteins, electron transport proteins and their regulators. PMID:23291738

  4. On and S isotopic composition of dissolved and attached oxidation products of pyrite by Acidithiobacillus ferrooxidans: Comparison with abiotic oxidations

    NASA Astrophysics Data System (ADS)

    Pisapia, Céline; Chaussidon, M.; Mustin, C.; Humbert, B.

    2007-05-01

    The acidophilic iron-oxidizing bacterium, Acidithiobacillus ferrooxidans, plays a part in the pyrite oxidation process and has been widely studied in order to determine the kinetics of the reactions and the isotopic composition of dissolved product sulphates, but the details of the oxidation processes at the surface of pyrite are still poorly known. In this study, oxygen and sulphur isotopic compositions (δ 18O and δ 34S) were analyzed for dissolved sulphates and water from experimental aerobic acidic (pH < 2) pyrite oxidation by A. ferrooxidans. The oxidation products attached to the pyrite surfaces were studied for their morphology (SEM), their chemistry (Raman spectroscopy) and for their δ 18O (ion microprobe). They were compared to abiotically (Fe 3+, H 2O 2, O 2) oxidized pyrite surface compounds in order to constrain the oxidation pathways and to look for the existence of potential biosignatures for this system. The pyrite dissolution evolved from non-stoichiometric (during the first days) to stoichiometric (with increasing time) resulting in dissolved sulphates having distinct δ 18O (e.g. +11.0‰ and -2.0‰, respectively) and δ 34S (+4.5‰ and +2.8‰, respectively) values. The "oxidation layer" at the surface of pyrite is complex and made of iron oxides, sulphate, polysulphide, elemental sulphur and polythionates. Bio- and Fe 3+-oxidation favour the development of monophased micrometric bumps made of hematite or sulphate while other abiotic oxidation processes result in more variable oxidation products. The δ 18O of these oxidation products at the surface of oxidized pyrites are strongly variable (from ≈-40‰ to ≈+30‰) for all experiments. Isotopic fractionation between sulphates and pyrite, Δ34S-pyrite, is equal to -1.3‰ and +0.4‰ for sulphates formed by stoichiometric and non-stoichiometric processes, respectively. These two values likely reflect either a S-S or a Fe-S bond breaking process. The Δ18O-HO and Δ18O-O are estimated to

  5. Addition of citrate to Acidithiobacillus ferrooxidans cultures enables precipitate-free growth at elevated pH and reduces ferric inhibition.

    PubMed

    Li, Xiaozheng; Mercado, Roel; Kernan, Timothy; West, Alan C; Banta, Scott

    2014-10-01

    Acidithiobacillus ferrooxidans is an acidophilic chemolithoautotroph that is important in biomining and other biotechnological operations. The cells are able to oxidize inorganic iron, but the insolubility and product inhibition by Fe(3+) complicates characterization of these cultures. Here we explore the growth kinetics of A. ferrooxidans in iron-based medium in a pH range from 1.6 to 2.2. It was found that as the pH was increased from 1.6 to 2.0, the maintenance coefficient decreased while both the growth kinetics and maximum cell yield increased in the precipitate-free, low Fe(2+) concentration medium. In higher iron media a similar trend was observed at low pH, but the formation of precipitates at higher pH (2.0) hampered cell growth and lowered the specific growth rate and maximum cell yield. In order to eliminate ferric precipitates, chelating agents were introduced into the medium. Citric acid was found to be relatively non-toxic and did not appear to interfere with iron oxidation at a maximum concentration of 70 mM. Inclusion of citric acid prevented precipitation and A. ferrooxidans growth parameters resumed their trends as a function of pH. The addition of citrate also decreased the apparent substrate saturation constant (KS ) indicating a reduction in the competitive inhibition of growth by ferric ions. These results indicate that continuous cultures of A. ferrooxidans in the presence of citrate at elevated pH will enable enhanced cell yields and productivities. This will be critical as these cells are used in the development of new biotechnological applications such as electrofuel production. PMID:24771134

  6. Comparative proteomic analysis of sulfur-oxidizing Acidithiobacillus ferrooxidans CCM 4253 cultures having lost the ability to couple anaerobic elemental sulfur oxidation with ferric iron reduction.

    PubMed

    Kucera, Jiri; Sedo, Ondrej; Potesil, David; Janiczek, Oldrich; Zdrahal, Zbynek; Mandl, Martin

    2016-09-01

    In extremely acidic environments, ferric iron can be a thermodynamically favorable electron acceptor during elemental sulfur oxidation by some Acidithiobacillus spp. under anoxic conditions. Quantitative 2D-PAGE proteomic analysis of a resting cell suspension of a sulfur-grown Acidithiobacillus ferrooxidans CCM 4253 subculture that had lost its iron-reducing activity revealed 147 protein spots that were downregulated relative to an iron-reducing resting cell suspension of the antecedent sulfur-oxidizing culture and 111 that were upregulated. Tandem mass spectrometric analysis of strongly downregulated spots identified several physiologically important proteins that apparently play roles in ferrous iron oxidation, including the outer membrane cytochrome Cyc2 and rusticyanin. Other strongly repressed proteins were associated with sulfur metabolism, including heterodisulfide reductase, thiosulfate:quinone oxidoreductase and sulfide:quinone reductase. Transcript-level analyses revealed additional downregulation of other respiratory genes. Components of the iron-oxidizing system thus apparently play central roles in anaerobic sulfur oxidation coupled with ferric iron reduction in the studied microbial strain. PMID:27394989

  7. Expression and activity of the Calvin-Benson-Bassham cycle transcriptional regulator CbbR from Acidithiobacillus ferrooxidans in Ralstonia eutropha.

    PubMed

    Esparza, Mario; Jedlicki, Eugenia; Dopson, Mark; Holmes, David S

    2015-08-01

    Autotrophic fixation of carbon dioxide into cellular carbon occurs via several pathways but quantitatively, the Calvin-Benson-Bassham cycle is the most important. CbbR regulates the expression of the cbb genes involved in CO2 fixation via the Calvin-Benson-Bassham cycle in a number of autotrophic bacteria. A gene potentially encoding CbbR (cbbR(AF)) has been predicted in the genome of the chemolithoautotrophic, extreme acidophile Acidithiobacillus ferrooxidans. However, this microorganism is recalcitrant to genetic manipulation impeding the experimental validation of bioinformatic predictions. Two novel functional assays were devised to advance our understanding of cbbR(AF) function using the mutated facultative autotroph Ralstonia eutropha H14 ΔcbbR as a surrogate host to test gene function: (i) cbbR(AF) was expressed in R. eutropha and was able to complement ΔcbbR; and (ii) CbbR(AF) was able to regulate the in vivo activity of four A. ferrooxidans cbb operon promoters in R. eutropha. These results open up the use of R. eutropha as a surrogate host to explore cbbR(AF) activity. PMID:26152700

  8. Catalytic effect of Ag⁺ on arsenic bioleaching from orpiment (As₂S₃) in batch tests with Acidithiobacillus ferrooxidans and Sulfobacillus sibiricus.

    PubMed

    Zhang, Guangji; Chao, Xingwu; Guo, Pei; Cao, Junya; Yang, Chao

    2015-01-01

    Orpiment is one of the major arsenic sulfide minerals which commonly occurs in the gold mine environment and the weathering of this mineral can lead to the contamination of arsenic. In this study, chemical leaching experiments using 10g/L Fe(3+) at 35°C and 50°C were carried out and the results show that orpiment can be leached by Fe(3+) and the leaching rate of orpiment was significantly enhanced in the presence of Ag(+). The bioleaching experiments with mesophilic bacteria Acidithiobacillus ferrooxidans and moderate thermophilic bacteria Sulfobacillus sibiricus were carried out, showing that these two strains can survive in the mineral pulp and oxidize Fe(2+) to regenerate Fe(3+). Based on above results, it is believed that the leaching action of the acidic mining drainage by some bacteria can lead to the release of arsenic from orpiment. Different performances of At. ferrooxidans and S. sibiricus in the tests suggest they follow two different mechanisms and this point of view is further confirmed based on analyses of the composition and morphology of the mineral residue by SEM and EDS. PMID:25265593

  9. Effects of electron transport inhibitors and uncouplers on the oxidation of ferrous iron and compounds interacting with ferric iron in Acidithiobacillus ferrooxidans.

    PubMed

    Chen, Yongqiang; Suzuki, Isamu

    2005-08-01

    Oxidation of Fe2+, ascorbic acid, propyl gallate, tiron, L-cysteine, and glutathione by Acidithiobacillus ferrooxidans was studied with respect to the effect of electron transport inhibitors and uncouplers on the rate of oxidation. All the oxidations were sensitive to inhibitors of cytochrome c oxidase, KCN, and NaN3. They were also partially inhibited by inhibitors of complex I and complex III of the electron transport system. Uncouplers at low concentrations stimulated the oxidation and inhibited it at higher concentrations. The oxidation rates of Fe2+ and L-cysteine inhibited by complex I and complex III inhibitors (amytal, rotenone, antimycin A, myxothiazol, and HQNO) were stimulated more extensively by uncouplers than the control rates. Atabrine, a flavin antagonist, was an exception, and atabrine-inhibited oxidation activities of all these compounds were further inhibited by uncouplers. A model for the electron transport pathways of A. ferrooxidans is proposed to account for these results. In the model these organic substrates reduce ferric iron on the surface of cells to ferrous iron, which is oxidized back to ferric iron through the Fe2+ oxidation pathway, leading to cytochrome oxidase to O2. Some of electrons enter the uphill (energy-requiring) electron transport pathway to reduce NAD+. Uncouplers at low concentrations stimulate Fe2+ oxidation by stimulating cytochrome oxidase by uncoupling. Higher concentrations lower deltap to the level insufficient to overcome the potentially uphill reaction at rusticyanin-cytochrome c4. Inhibition of uphill reactions at complex I and complex III leads to deltap accumulation and inhibition of cytochrome oxidase. Uncouplers remove the inhibition of deltap and stimulate the oxidation. Atabrine inhibition is not released by uncouplers, which implies a possibility of atabrine inhibition at a site other than complex I, but a site somehow involved in the Fe2+ oxidation pathway. PMID:16234867

  10. Differential expression of sulfur assimilation pathway genes in Acidithiobacillus ferrooxidans under Cd²⁺ stress: evidence from transcriptional, enzymatic, and metabolic profiles.

    PubMed

    Zheng, Chunli; Chen, Minjie; Tao, Zhanlong; Zhang, Li; Zhang, Xue Feng; Wang, Jian-Ying; Liu, Jianshe

    2015-03-01

    Acidithiobacillus ferrooxidans is a heavy metal-tolerant acidophilic chemolithotroph found in acidic mine effluent and is used commercially in the bioleaching of sulfide ores. In this work, we investigated the interplay between divalent cadmium (Cd(2+)) resistance and expression of genes involved in the sulfur assimilation pathway (SAP). We also investigated the response of the thiol-containing metal-chelating metabolites, cysteine and glutathione(GSH), to increasing Cd(2+) concentrations. During growth in the presence of 30 mM Cd(2+), the concentrations of mRNA for 5 genes in the SAP pathway increased more than fourfold: these encode ATP sulfurylase (ATPS), adenosine 5'-phosphosulfate (APS) reductase, sulfite reductase (SiR), serine acetyltransferase (SAT) and O-acetylserine (thiol) lyase (OAS-TL). Increased transcription was also reflected in increased enzyme activities: those of SAT and adenosylphosphosulfate reductase (APR) reached a peak of 26- and 15.8-fold, respectively, compared to the control culture in the presence of 15 mM Cd(2+). In contrast, the activity of OAS-TL, which is responsible for the biosynthesis of cysteine, was diminished. At the metabolite level, the intracellular cysteine and GSH contents nearly doubled. These results suggested that Cd(2+) induced transcription of SAP genes, while directly inhibiting the activities of some enzymes (e.g., OAS-TL). Overall, these results are consistent with a detoxification/resistance mechanism involving enhanced sulfur uptake and sequestration of Cd(2+) by cysteine and glutathione. PMID:25575615

  11. Effect of calcium oxide on the efficiency of ferrous ion oxidation and total iron precipitation during ferrous ion oxidation in simulated acid mine drainage treatment with inoculation of Acidithiobacillus ferrooxidans.

    PubMed

    Liu, Fenwu; Zhou, Jun; Jin, Tongjun; Zhang, Shasha; Liu, Lanlan

    2016-01-01

    Calcium oxide was added into ferrous ion oxidation system in the presence of Acidithiobacillus ferrooxidans at concentrations of 0-4.00 g/L. The pH, ferrous ion oxidation efficiency, total iron precipitation efficiency, and phase of the solid minerals harvested from different treatments were investigated during the ferrous ion oxidation process. In control check (CK) system, pH of the solution decreased from 2.81 to 2.25 when ferrous ions achieved complete oxidation after 72 h of Acidithiobacillus ferrooxidans incubation without the addition of calcium oxide, and total iron precipitation efficiency reached 20.2%. Efficiency of ferrous ion oxidation and total iron precipitation was significantly improved when the amount of calcium oxide added was ≤1.33 g/L, and the minerals harvested from systems were mainly a mixture of jarosite and schwertmannite. For example, the ferrous ion oxidation efficiency reached 100% at 60 h and total iron precipitation efficiency was increased to 32.1% at 72 h when 1.33 g/L of calcium oxide was added. However, ferrous ion oxidation and total iron precipitation for jarosite and schwertmannite formation were inhibited if the amount of calcium oxide added was above 2.67 g/L, and large amounts of calcium sulfate dihydrate were generated in systems. PMID:27003087

  12. Different isotope and chemical patterns of pyrite oxidation related to lag and exponential growth phases of Acidithiobacillus ferrooxidans reveal a microbial growth strategy

    NASA Astrophysics Data System (ADS)

    Brunner, Benjamin; Yu, Jae-Young; Mielke, Randall E.; MacAskill, John A.; Madzunkov, Stojan; McGenity, Terry J.; Coleman, Max

    2008-06-01

    The solution chemistry during the initial (slow increase of dissolved iron and sulfate) and main stage (rapid increase of dissolved iron and sulfate) of pyrite leaching by Acidithiobacillus ferrooxidans (Af) at a starting pH of 2.05 shows significant differences. During the initial stage, ferrous iron (Fe2+) is the dominant iron species in solution and the molar ratio of produced sulfate (SO42-) and total iron (Fetot) is 1.1, thus does not reflect the stoichiometry of pyrite (FeS2). During the main stage, ferric iron (Fe3+) is the dominant iron species in solution and the SO42-:Fetot ratio is with 1.9, close to the stoichiometry of FeS2. Another difference between initial and main stage is an initial trend to slightly higher pH values followed by a drop during the main stage to pH 1.84. These observations raise the question if there are different modes of bioleaching of pyrite, and if there are, what those modes imply in terms of leaching mechanisms. Different oxygen and sulfur isotope trends of sulfate during the initial and main stages of pyrite oxidation confirm that there are two pyrite bioleaching modes. The biochemical reactions during initial stage are best explained by the net reaction FeS2 + 3O2 ⇒ Fe2+ + SO42- + SO2(g). The degassing of sulfur dioxide (SO2) acts as sink for sulfur depleted in 34S compared to pyrite, and is the cause of the SO42-:Fetot ratio of 1.1 and the near constant pH. During the exponential phase, pyrite sulfur is almost quantitatively converted to sulfate, according to the net reaction FeS2 + 15/4O2 + 1/2H2O ⇒ Fe3+ + 2SO42- + H+. We hypothesize that the transition between the modes of bioleaching of pyrite is due to the impact of the accumulation of ferrous iron, which induces changes in the metabolic activity of Af and may act as an inhibitor for the oxidation of sulfur species. This transition defines a fundamental change in the growth strategy of Af. A mode, where bacteria gain energy by oxidation of elemental sulfur to

  13. Characterization of an Operon Encoding Two c-Type Cytochromes, an aa3-Type Cytochrome Oxidase, and Rusticyanin in Thiobacillus ferrooxidans ATCC 33020

    PubMed Central

    Appia-Ayme, Corinne; Guiliani, Nicolas; Ratouchniak, Jeanine; Bonnefoy, Violaine

    1999-01-01

    Despite the importance of Thiobacillus ferrooxidans in bioremediation and bioleaching, little is known about the genes encoding electron transfer proteins implicated in its energetic metabolism. This paper reports the sequences of the four cox genes encoding the subunits of an aa3-type cytochrome c oxidase. These genes are in a locus containing four other genes: cyc2, which encodes a high-molecular-weight cytochrome c; cyc1, which encodes a c4-type cytochrome (c552); open reading frame 1, which encodes a putative periplasmic protein of unknown function; and rus, which encodes rusticyanin. The results of Northern and reverse transcription-PCR analyses indicated that these eight genes are cotranscribed. Two transcriptional start sites were identified for this operon. Upstream from each of the start sites was a ς70-type promoter recognized in Escherichia coli. While transcription in sulfur-grown T. ferrooxidans cells was detected from the two promoters, transcription in ferrous-iron-grown T. ferrooxidans cells was detected only from the downstream promoter. The cotranscription of seven genes encoding redox proteins suggests that all these proteins are involved in the same electron transfer chain; a model taking into account the biochemistry and the genetic data is discussed. PMID:10543786

  14. Growth of Thiobacillus ferrooxidans on formic acid

    SciTech Connect

    Pronk, J.T.; Meijer, W.M.; Hazeu, W.; vanDijken, J.P.; Bos, P.; Kuenen, J.G. )

    1991-07-01

    A variety of acidophilic microorganisms were shown to be capable of oxidizing formate. These included Thiobacillus ferrooxidans ATCC 21834, which, however, could not grow on formate in normal batch cultures. However, the organism could be grown on formate when the substrate supply was growth limiting, e.g., in formate-limited chemostat cultures. The cell densities achieved by the use of the latter cultivation method were higher than cell densities reported for growth of T. ferrooxidans on ferrous iron or reduced sulfur compounds. Inhibition of formate oxidation by cell suspensions, but not cell extracts, of formate-grown T. ferrooxidans occurred at formate concentrations above 100 {mu}M. This observation explains the inability of the organism to grow on formate in batch cultures. Cells grown in formate-limited chemostat cultures retained the ability to oxidize ferrous iron at high rates. Ribulose 1,5-bisphosphate carboxylase activities in cell extracts indicated that T. ferrooxidans employs the Calvin cycle for carbon assimilation during growth on formate. Oxidation of formate by cell extracts was NAD(P) independent.

  15. Gene identification and substrate regulation provide insights into sulfur accumulation during bioleaching with the psychrotolerant acidophile Acidithiobacillus ferrivorans.

    PubMed

    Liljeqvist, Maria; Rzhepishevska, Olena I; Dopson, Mark

    2013-02-01

    The psychrotolerant acidophile Acidithiobacillus ferrivorans has been identified from cold environments and has been shown to use ferrous iron and inorganic sulfur compounds as its energy sources. A bioinformatic evaluation presented in this study suggested that Acidithiobacillus ferrivorans utilized a ferrous iron oxidation pathway similar to that of the related species Acidithiobacillus ferrooxidans. However, the inorganic sulfur oxidation pathway was less clear, since the Acidithiobacillus ferrivorans genome contained genes from both Acidithiobacillus ferrooxidans and Acidithiobacillus caldus encoding enzymes whose assigned functions are redundant. Transcriptional analysis revealed that the petA1 and petB1 genes (implicated in ferrous iron oxidation) were downregulated upon growth on the inorganic sulfur compound tetrathionate but were on average 10.5-fold upregulated in the presence of ferrous iron. In contrast, expression of cyoB1 (involved in inorganic sulfur compound oxidation) was decreased 6.6-fold upon growth on ferrous iron alone. Competition assays between ferrous iron and tetrathionate with Acidithiobacillus ferrivorans SS3 precultured on chalcopyrite mineral showed a preference for ferrous iron oxidation over tetrathionate oxidation. Also, pure and mixed cultures of psychrotolerant acidophiles were utilized for the bioleaching of metal sulfide minerals in stirred tank reactors at 5 and 25°C in order to investigate the fate of ferrous iron and inorganic sulfur compounds. Solid sulfur accumulated in bioleaching cultures growing on a chalcopyrite concentrate. Sulfur accumulation halted mineral solubilization, but sulfur was oxidized after metal release had ceased. The data indicated that ferrous iron was preferentially oxidized during growth on chalcopyrite, a finding with important implications for biomining in cold environments. PMID:23183980

  16. Identification of Thiobacillus ferrooxidans strains based on restriction fragment length polymorphism analysis of 16S rDNA.

    PubMed

    Kamimura, K; Wakai, S; Sugio, T

    2001-01-01

    The 16S rDNA sequences from ten strains of Thiobacillus ferrooxidans were amplified by PCR. The products were compared by performing restriction fragment length polymorphism (RFLP) analysis with restriction endonucleases Alu I, Hap II, Hha I, and Hae III. The RFLP patterns revealed that T. ferrooxidans could be distinguished from other iron- or sulphur-oxidizing bacteria such as T. thiooxidans NB1-3, T. caldus GO-1, Leptospirillum ferrooxidans and the marine iron-oxidizing bacterium strain KU2-11. The RFLP patterns obtained with Alu I, Hap II, and Hae III were the same for nine strains of T. ferrooxidans except for strain ATCC 13661. The RFLP patterns for strains NASF-1 and ATCC 13661 with Hha I were distinct from those for other T. ferrooxidans strains. The 16S rDNA sequence of T. ferrooxidans NASF-1 possessed an additional restriction site for Hha I. These results show that iron-oxidizing bacteria isolated from natural environments were rapidly identified as T. ferrooxidans by the method combining RFLP analysis with physiological analysis. PMID:11414499

  17. Construction and Characterization of a recA Mutant of Thiobacillus ferrooxidans by Marker Exchange Mutagenesis

    PubMed Central

    Liu, Zhenying; Guiliani, Nicolas; Appia-Ayme, Corinne; Borne, Françoise; Ratouchniak, Jeanine; Bonnefoy, Violaine

    2000-01-01

    To construct Thiobacillus ferrooxidans mutants by marker exchange mutagenesis, a genetic transfer system is required. The transfer of broad-host-range plasmids belonging to the incompatibility groups IncQ (pKT240 and pJRD215), IncP (pJB3Km1), and IncW (pUFR034) from Escherichia coli to two private T. ferrooxidans strains (BRGM1 and Tf-49) and to two collection strains (ATCC 33020 and ATCC 19859) by conjugation was analyzed. To knock out the T. ferrooxidans recA gene, a mobilizable suicide plasmid carrying the ATCC 33020 recA gene disrupted by a kanamycin resistance gene was transferred from E. coli to T. ferrooxidans ATCC 33020 by conjugation under the best conditions determined. The two kanamycin-resistant clones, which have retained the kanamycin-resistant phenotype after growth for several generations in nonselective medium, were shown to have the kanamycin resistance gene inserted within the recA gene, indicating that the recA::Ω-Km mutated allele was transferred from the suicide plasmid to the chromosome by homologous recombination. These mutants exhibited a slightly reduced growth rate and an increased sensitivity to UV and γ irradiation compared to the wild-type strain. However, the T. ferrooxidans recA mutants are less sensitive to these physical DNA-damaging agents than the recA mutants described in other bacterial species, suggesting that RecA plays a minor role in DNA repair in T. ferrooxidans. PMID:10735871

  18. Recovery of Nickel and Cobalt from Laterite Tailings by Reductive Dissolution under Aerobic Conditions Using Acidithiobacillus Species.

    PubMed

    Marrero, J; Coto, O; Goldmann, S; Graupner, T; Schippers, A

    2015-06-01

    Biomining of sulfidic ores has been applied for almost five decades. However, the bioprocessing of oxide ores such as laterites lags commercially behind. Recently, the Ferredox process was proposed to treat limonitic laterite ores by means of anaerobic reductive dissolution (AnRD), which was found to be more effective than aerobic bioleaching by fungi and other bacteria. We show here that the ferric iron reduction mediated by Acidithiobacillus thiooxidans can be applied to an aerobic reductive dissolution (AeRD) of nickel laterite tailings. AeRD using a consortium of Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans extracted similar amounts of nickel (53-57%) and cobalt (55-60%) in only 7 days as AnRD using Acidithiobacillus ferrooxidans. The economic and environmental advantages of AeRD for processing of laterite tailings comprise no requirement for an anoxic atmosphere, 1.8-fold less acid consumption than for AnRD, as well as nickel and cobalt recovered in a ferrous-based pregnant leach solution (PLS), facilitating the subsequent metal recovery. In addition, an aerobic acid regeneration stage is proposed. Therefore, AeRD process development can be considered as environmentally friendly for treating laterites with low operational costs and as an attractive alternative to AnRD. PMID:25923144

  19. Evaluation of Leptospirillum ferrooxidans for Leaching

    PubMed Central

    Sand, Wolfgang; Rohde, Katrin; Sobotke, Birgit; Zenneck, Claus

    1992-01-01

    The importance of Leptospirillum ferrooxidans for leach processes has been evaluated by studying the lithotrophic flora of three mine biotopes and a heap leaching operation, by percolation experiments with inoculated, sterilized ore, and by morphological, physiological, and genetic investigations of pure and mixed cultures of L. ferrooxidans, Thiobacillus ferrooxidans, and Thiobacillus thiooxidans. In biotopes of 20°C or above, Leptospirillum-like bacteria are as abundant as T. ferrooxidans. Leptospirilli represent at least one-half of the ferrous-iron-oxidizing population. Percolation experiments confirmed this result. Leptospirilli were as numerous as T. ferrooxidans. At reduced temperatures, the generation times of leptospirilli increase more so than those of T. ferrooxidans. At 14°C, Leptospirillum grows slowly and T. ferrooxidans dominates the population. Physiological investigations indicate that L. ferrooxidans is a strict chemolithoautotroph, metabolizing only ferrous iron and pyrite. Even an addition of 0.05% (wt/vol) yeast extract inhibited its growth. The maximum ferrous-iron-oxidizing activity of L. ferrooxidans amounts to about 40% of the activity of T. ferrooxidans. After growth on sulfidic ore, both species exhibit reduced iron-oxidizing activities, L. ferrooxidans exhibiting one-third and T. ferrooxidans exhibiting one-seventh of their maximum activities. Surprisingly, the absolute values are similar. For indirect leaching, L. ferrooxidans is as important as T. ferrooxidans. This was confirmed by the results of percolation experiments. L. ferrooxidans together with T. thiooxidans mobilized metals at least as well as T. ferrooxidans did. The best results were obtained with a mixed culture of all three species. Images PMID:16348642

  20. Bioleaching of metals from steel slag by Acidithiobacillus thiooxidans culture supernatant.

    PubMed

    Hocheng, Hong; Su, Cheer; Jadhav, Umesh U

    2014-12-01

    The generation of 300–500 kg of slag per ton of the steel produced is a formidable amount of solid waste available for treatment. They usually contain considerable quantities of valuable metals. In this sense, they may become either important secondary resource if processed in eco-friendly manner for secured supply of contained metals or potential pollutants, if not treated properly. It is possible to recover metals from steel slag by applying bioleaching process. Electric arc furnace (EAF) slag sample was used for bioleaching of metals. In the present study, before bioleaching experiment water washing of an EAF slag was carried out. This reduced slag pH from 11.2 to 8.3. Culture supernatants of Acidithiobacillus thiooxidans (At. thiooxidans), Acidithiobacillus ferrooxidans (At. ferrooxidans), and Aspergillus niger (A. niger) were used for metal solubilization. At. thiooxidans culture supernatant containing 0.016 M sulfuric acid was found most effective for bioleaching of metals from an EAF slag. Maximum metal extraction was found for Mg (28%), while it was least for Mo (0.1%) in six days. Repeated bioleaching cycles increased metal recovery from 28% to 75%, from 14% to 60% and from 11% to 27%, for Mg, Zn and Cu respectively. PMID:25461931

  1. Molecular genetics of Thiobacillus ferrooxidans.

    PubMed Central

    Rawlings, D E; Kusano, T

    1994-01-01

    Thiobacillus ferrooxidans is a gram-negative, highly acidophilic (pH 1.5 to 2.0), autotrophic bacterium that obtains its energy through the oxidation of ferrous iron or reduced inorganic sulfur compounds. It is usually dominant in the mixed bacterial populations that are used industrially for the extraction of metals such as copper and uranium from their ores. More recently, these bacterial consortia have been used for the biooxidation of refractory gold-bearing arsenopyrite ores prior to the recovery of gold by cyanidation. The commercial use of T. ferrooxidans has led to an increasing interest in the genetics and molecular biology of the bacterium. Initial investigations were aimed at determining whether the unique physiology and specialized habitat of T. ferrooxidans had been accompanied by a high degree of genetic drift from other gram-negative bacteria. Early genetic studies were comparative in nature and concerned the isolation of genes such as nifHDK, glnA, and recA, which are widespread among bacteria. From a molecular biology viewpoint, T. ferrooxidans appears to be a typical member of the proteobacteria. In most instances, cloned gene promoters and protein products have been functional in Escherichia coli. Although T. ferrooxidans has proved difficult to transform with DNA, research on indigenous plasmids and the isolation of the T. ferrooxidans merA gene have resulted in the development of a low-efficiency electroporation system for one strain of T. ferrooxidans. The most recent studies have focused on the molecular genetics of the pathways associated with nitrogen metabolism, carbon dioxide fixation, and components of the energy-producing mechanisms. PMID:8177170

  2. Improved chalcopyrite bioleaching by Acidithiobacillus sp. via direct step-wise regulation of microbial community structure.

    PubMed

    Feng, Shoushuai; Yang, Hailin; Wang, Wu

    2015-09-01

    A direct step-wise regulation strategy of microbial community structure was developed for improving chalcopyrite bioleaching by Acidithiobacillus sp. Specially, the initial microbial proportion between Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans was controlled at 3:1 with additional 2 g/L Fe(2+) for faster initiating iron metabolism. A. thiooxidans biomass was fed via a step-wise strategy (8-12th d) with the microbial proportion 1:1 for balancing community structure and promoting sulfur metabolism in the stationary phase. A. thiooxidans proportion was further improved via another step-wise feeding strategy (14-18th d) with the microbial proportion 1:2 for enhancing sulfur metabolism and weakening jarosite passivation in the later phase. With the community structure-shift control strategy, biochemical reaction was directly regulated for creating a better balance in different phases. Moreover, the final copper ion was increased from 57.1 to 93.2 mg/L, with the productivity 2.33 mg/(Ld). The novel strategy may be valuable in optimization of similar bioleaching process. PMID:26011694

  3. Sulfur-binding protein of flagella of Thiobacillus ferrooxidans.

    PubMed

    Ohmura, N; Tsugita, K; Koizumi, J I; Saika, H

    1996-10-01

    The sulfur-binding protein of Thiobacillus ferrooxidans ATCC 23270 was investigated. The protein composition of the bacterium's cell surface changed according to the culture substrate. Sulfur-grown cells showed greater adhesion to sulfur than iron-grown cells. The sulfur-grown cells synthesized a 40-kDa surface protein which was not synthesized by iron-grown cells. The 40-kDa protein had thiol groups and strongly adhered to elemental sulfur powder. This adhesion was not disturbed by Triton X-100, which can quench hydrophobic interactions. However, adhesion was disturbed by 2-mercaptoethanol, which broke the disulfide bond. The thiol groups of the 40-kDa protein formed a disulfide bond with elemental sulfur and mediated the strong adhesion between T. ferrooxidans cells and elemental sulfur. The 40-kDa protein was located on the flagella. The location of the protein would make it possible for cells to be in closer contact with the surface of elemental sulfur powder. PMID:8824625

  4. Sulfur-binding protein of flagella of Thiobacillus ferrooxidans.

    PubMed Central

    Ohmura, N; Tsugita, K; Koizumi, J I; Saika, H

    1996-01-01

    The sulfur-binding protein of Thiobacillus ferrooxidans ATCC 23270 was investigated. The protein composition of the bacterium's cell surface changed according to the culture substrate. Sulfur-grown cells showed greater adhesion to sulfur than iron-grown cells. The sulfur-grown cells synthesized a 40-kDa surface protein which was not synthesized by iron-grown cells. The 40-kDa protein had thiol groups and strongly adhered to elemental sulfur powder. This adhesion was not disturbed by Triton X-100, which can quench hydrophobic interactions. However, adhesion was disturbed by 2-mercaptoethanol, which broke the disulfide bond. The thiol groups of the 40-kDa protein formed a disulfide bond with elemental sulfur and mediated the strong adhesion between T. ferrooxidans cells and elemental sulfur. The 40-kDa protein was located on the flagella. The location of the protein would make it possible for cells to be in closer contact with the surface of elemental sulfur powder. PMID:8824625

  5. Geochemical diversity in S processes mediated by culture-adapted and environmental-enrichments of Acidithiobacillus spp.

    NASA Astrophysics Data System (ADS)

    Bernier, Luc; Warren, Lesley A.

    2007-12-01

    Coupled S speciation and acid generation resulting from S processing associated with five different microbial treatments, all primarily Acidithiobacillus spp. (i.e. autotrophic S-oxidizers) were evaluated in batch laboratory experiments. Microbial treatments included two culture-adapted strains, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans, their consortia and two environmental enrichments from a mine tailings lake that were determined to be >95% Acidithiobacillus spp., by whole-cell fluorescent hybridization. Using batch experiments simulating acidic mine waters with no carbon amendments, acid generation, and S speciation associated with the oxidation of three S substrates (thiosulfate, tetrathionate, and elemental S) were evaluated. Aseptic controls showed no observable pH decrease over the experimental time course (1 month) for all three S compounds examined. In contrast, pH decreased in all microbial treatments from starting pH values of 4 to 2 or less for all three S substrates. Results show a non-linear relationship between the pH dynamics of the batch cultures and their corresponding sulfate concentrations, and indicate how known microbial S processing pathways have opposite impacts, ultimately on pH dynamics. Associated geochemical modeling indicated negligible abiogenic processes contributing to the observed results, indicating strong microbial control of acid generation extending over pH ranges from 4 to less than 2. However, the observed acid generation rates and associated S speciation were both microbial treatment and substrate-specific. Results reveal a number of novel insights regarding microbial catalysis of S oxidation: (1) metabolic diversity in S processing, as evidenced by the observed geochemical signatures in S chemical speciation and rates of acid generation amongst phylogenetically similar organisms (to the genus level); (2) consortial impacts differ from those of individual strain members; (3) environmental enrichments

  6. Phospholipid Metabolism in Ferrobacillus ferrooxidans

    PubMed Central

    Short, Steven A.; White, David C.; Aleem, M. I. H.

    1969-01-01

    The lipid composition of the chemoautotroph Ferrobacillus ferrooxidans has been examined. Fatty acids represent 2% of the dry weight of the cells and 86% of the total are extractable with organic solvents. About 25% of the total fatty acids are associated with diacyl phospholipids. Polar carotenoids, the benzoquinone coenzyme Q-8, and most of the fatty acids are present in the neutral lipids. The phospholipids have been identified as phosphatidyl monomethylethanolamine (42%), phosphatidyl glycerol (23%), phosphatidyl ethanolamine (20%), cardiolipin (13%), phosphatidyl choline (1.5%), and phosphatidyl dimethylethanolamine (1%) by chromatography of the diacyl lipids, by chromatography in four systems of the glycerol phosphate esters derived from the lipids by mild alkaline methanolysis, and by chromatographic identification of the products of acid hydrolysis of the esters. No trace of phosphatidylserine (PS), glycerolphosphorylserine, or serine could be detected in the lipid extract or in derivatives of that extract. This casts some doubt on the postulated involvement of PS in iron metabolism. After growth in the presence of 14C and 32P, there was essentially no difference in the turnover of either isotope in the glycerolphosphate ester derived from each lipid in cells grown at pH 1.5 or 3.5. Images PMID:5802599

  7. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

    SciTech Connect

    Pesic, B.; Oliver, D.J.; Kim, Inbeum; De, G.C.

    1993-01-20

    A cyclic voltammetry technique was used to study the interactions of pyrite during bioleaching with the bacterium Thiobacillus ferrooxidans. Potential effects of heavy metals (silver and mercury) and varying the pH on the iron oxidizing ability of the bacterium are reported. Redox potential techniques were used to study effect of ferrous sulfate concentration and pH on bacterial growth.

  8. [Inhibition of Low Molecular Organic Acids on the Activity of Acidithiobacillus Species and Its Effect on the Removal of Heavy Metals from Contaminated Soil].

    PubMed

    Song, Yong-wei; Wang, He-rul; Cao, Yan-xiao; Li, Fei; Cui, Chun-hong; Zhou, Li

    2016-05-15

    Application of organic fertilizer can reduce the solubility and bioavailability of heavy metals in contaminated soil, but in the flooded anaerobic environment, organic fertilizer will be decomposed to produce a large number of low molecular organic acids, which can inhibit the biological activity of Acidithiobacillus species. Batch cultures studies showed that the monocarboxylic organic acids including formic acid, acetic acid, propionic acid, and butyric acid exhibited a marked toxicity to Acidithiobacillus species, as indicated by that 90% of inhibitory rate for Fe2 and So oxidation in 72 h were achieved at extremely low concentrations of 41.2 mg · L⁻¹, 78.3 mg · L⁻¹, 43.2 mg · L⁻¹, 123.4 mg · L⁻¹ and 81.9 mg 230. 4 mg · L⁻¹, 170.1 mg · L⁻¹, 123.4 mg · L⁻¹ respectively. Of these organic acids, formic acid was the most toxic one as indicated by that Fe2 and So oxidation was almost entirely inhibited at a low concentration. In addition, it was found that Acidithiobacillus ferrooxidans was more sensitive to low molecular organic acids than Acidithiobacillus thiooxidans. What's more, there was little effect on biological acidification process of heavy metal contaminated soil when organic acids were added at initial stage (Oh), but it was completely inhibited when these acids were added after 12 h of conventional biological acidification, thus decreasing the efficiency of heavy metals dissolution from soil. PMID:27506054

  9. Biosynthesis of bifunctional iron oxyhydrosulfate by Acidithiobacillus ferroxidans and their application to coagulation and adsorption.

    PubMed

    Gan, Min; Song, Zibo; Jie, Shiqi; Zhu, Jianyu; Zhu, Yaowu; Liu, Xinxing

    2016-02-01

    Coagulation and adsorption are important environmental technologies, which were widely applied in water treatment. In this study, a type of villous iron oxyhydrosulfate with low crystallinity, high content iron, sulfate and hydroxyl was synthesized by Acidithiobacillus ferrooxidans, which possessed coagulation and heavy metal adsorption ability simultaneously. The results showed that the Cu(II) adsorption capacity increased within a small range over the pH range of 3.0-5.0 but increased evidently over the range of 6.0-8.0. The maximal Cu(II) adsorption capacity of sample Af and Gf reached 50.97 and 46.08mg/g respectively. The optimum pH for Cr(VI) adsorption was 6.0, and the maximal adsorption capacity reached 51.32 and 59.57mg/g. The Langmuir isotherm can better describe the adsorption behavior of Cr(VI). Coagulation performance of the iron oxyhydrosulfate (Sh) has been significantly enhanced by polysilicic acid (PSA), which was mainly determined by PSA/Sh ratio, pH and coagulant dosage. Coagulation efficiency maintained approximately at 98% when the PSA/Sh ratio ranged from 0.4/0.1 to 1.0/0.1. Polysilicic acid worked efficiently in wide pH range extending, from 2 to 3.5. Coagulation performance improved significantly with the increasing of the coagulant dosage at lower dosage range, while, at higher dosage range, the improvement was not evident even with more coagulant addition. PMID:26652457

  10. Improved Experimental and Computational Methodology for Determining the Kinetic Equation and the Extant Kinetic Constants of Fe(II) Oxidation by Acidithiobacillus ferrooxidans▿

    PubMed Central

    Molchanov, Sharon; Gendel, Yuri; Ioslvich, Ilya; Lahav, Ori

    2007-01-01

    The variety of kinetics expressions encountered in the literature and the unreasonably broad range of values reported for the kinetics constants of Acidithiobacillus ferrooxidans underscore the need for a unifying experimental procedure and for the development of a reliable kinetics equation. Following an extensive and critical review of reported experimental techniques, a method based on batch pH-controlled kinetics experiments lasting less than one doubling time was developed for the determination of extant kinetics constants. The Fe(II) concentration in the experiments was measured by a method insensitive to Fe(III) interference. Kinetics parameters were determined by nonlinear fitting of the integrated form of the Monod equation to yield a KS of 31 ± 4 mg Fe2+ liter−1 (mean ± standard deviation), a KP of 139 ± 20 mg Fe3+ liter−1, and a μmax of 0.082 ± 0.002 h−1. The corresponding kinetics equation was as follows: \\documentclass[10pt]{article} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{pmc} \\pagestyle{empty} \\oddsidemargin -1.0in \\begin{document} \\begin{equation*}\\frac{dS}{dt}= \\left \\left(-\\frac{0.082}{2.3{\\cdot}10^{7}}\\right) \\right \\frac{S{\\cdot}X}{31(1+\\displaystyle\\frac{P_{0}+S_{0}-S}{139})+S}\\end{equation*}\\end{document} where S represents the Fe(II) concentration in mg liter−1, P0 represents the initial Fe(III) concentration in mg liter−1, X represents the suspended bacterial cell concentration in cells ml−1, and t represents time in hours. The measured data fit this equation exceptionally well, with an R2 of >0.99. Fe(III) inhibition was found to be of a competitive nature. Contrary to previous reports, the results show that the concentration of Acidithiobacillus ferrooxidans cells has no affect on the kinetics constants. The kinetics equation can be considered applicable only to A. ferrooxidans cells grown under

  11. Electrochemistry of thiobacillus ferrooxidans interactions with pyrite

    NASA Astrophysics Data System (ADS)

    Pesic, Batric; Kim, Inbeum

    1993-10-01

    A cyclic voltammetry technique was used to study the interactions of mineral-pyrite during bioleaching with the bacterium Thiobacillus (T.) ferrooxidans over its entire growth cycle. Invariably, the pyrite surface drastically changed its properties on the second day of bacterial rowth (bioleaching). After 2 days, the cyclic voltammograms (CVs) were insensitive to convective diffusion produced by stirring. The product layer was examined by scanning electron microscopy (SEM), X-ray diffraction, and chemical analysis. The SEM study revealed an extremely high density of bacteria on the pyrite surface. The high density of bacteria, along with the solid reaction products formed on the pyrite surface, created conditions for crack/pore diffusion, explaining why the CVs became insensitive to convective diffusion (stirring) in solution. X-ray diffraction study confirmed jarosite as a product layer. A mechanism is proposed by which T. ferrooxidans cells serve as nucleation sites for jarosite formation.

  12. Electrochemistry of Thiobacillus ferrooxidans interactions with pyrite

    SciTech Connect

    Pesic, B. . Coll. of Mines and Earth Resources); Kim, I. )

    1993-10-01

    A cyclic voltammetry technique was used to study the interactions of mineral-pyrite during bioleaching with the bacterium Thiobacillus (T.) ferrooxidans over its entire growth cycle. Invariably, the pyrite surface drastically changed its properties on the second day of bacterial growth (bioleaching). After 2 days, the cyclic voltammograms (CVs) were insensitive to convective diffusion produced by stirring. The product layer was examined by scanning electron microscopy (SEM), X-ray diffraction, and chemical analysis. The SEM study revealed an extremely high density of bacteria on the pyrite surface. The high density of bacteria, along with the solid reaction products formed on the pyrite surface, created conditions for crack/pore diffusion, explaining why the CVs became insensitive to convective diffusion (stirring) in solution. X-ray diffraction study confirmed jarosite as a product layer. A mechanism is proposed by which T. ferrooxidans cells serve as nucleation sites for jarosite formation.

  13. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

    SciTech Connect

    Pesic, B.

    1991-01-01

    The interactions of mineral-pyrite with T. ferrooxidans were studied by using a cyclic voltametry technique. The interactions with bacteria were examined during the entire growth stage of bacterial (fermentation). The pyrite surface invariably drastically changed its properties at the second day of fermentation. Beyond two days of fermentation, the cyclic voltamograms were insensitive to convective diffusion produced by stirring. The product layer was examined by SEM, X-ray diffraction and chemical analysis. The SEM study revealed that bacteria populated the pyrite surface at an extremely high density levels. The high density of bacteria, and the solid reaction products formed on the pyrite surface created conditions for pore diffusion which explained why the CVs became insensitive to convective diffusion in solution (stirring). The X-ray diffraction study confirmed jarosite as a product layer. A mechanism of T. ferrooxidans cells serving as nucleation sites for jarosite formation is proposed. 16 refs., 8 figs., 2 tabs.

  14. Cellulase producing microorganism ATCC 55702

    DOEpatents

    Dees, H. Craig

    1997-01-01

    Bacteria which produce large amounts of cellulase--containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualifies for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

  15. Cellulase producing microorganism ATCC 55702

    DOEpatents

    Dees, H.C.

    1997-12-30

    Bacteria which produce large amounts of cellulase--containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualifies for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques. 5 figs.

  16. Microbial desulfurization of coal. [Leptospirillum ferrooxidans

    SciTech Connect

    Andrews, G.F.; Dugan, P.R.; McIlwain, M.E.; Stevens, C.J.

    1992-03-01

    A bacterial coal depyritization process was operated at a large laboratory scale for four months treating almost 500 kg of an Illinois {number sign}6 coal supplied by the Monterey Coal Company and ground to 80% minus 100 mesh. The main features of the process were a 200-{ell} aerated trough bioreactor consisting of a channel 2.44 m long with a porous aeration tube running along its V-shaped bottom, an inclined 40 {mu}m screen for dewatering the coal slurry, and a liquid recycle stream to inoculate the incoming coal with the bacteria and ferric ion required for pyrite removal. The process was started up with large numbers of Thiobacillus ferrooxidans and Leptospirillum ferrooxidans bacteria grown on iron media in a specially built electrolysis cell. Natural selection pressures then created a mixed culture well adapted to the coal from these bacteria, smaller numbers of T. thiooxidans added later, and the bacteria carried into the system with the coal. The process was run at 2.0 < pH < 2.7 and 18{degrees}C < temperature < 22{degrees}C.

  17. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

    SciTech Connect

    Pesic, B.

    1990-01-01

    The present investigation is a part of our studies on the electrochemical aspects of pyrite bioleaching involving Thiobacillus ferrooxidans. Previously we have examined the effect of T. ferrooxidans and their metabolic products on the redox reactions of Fe{sup 2+}/Fe{sup 3+} couple at the pyrite surface. Results obtained suggest that beyond 1.5 days during their growth in a batch fermenter, the bacteria and their metabolic products completely cover the pyrite surface and shut down all electron transfer across the electrode-solution interface. In addition, it has been observed that the bacteria serve as the nucleation site for jarosite formation, which is found detrimental to bioleaching. In the present work we have focused on the effect of the presence of vitamins on the redox chemistry of iron. To date, we have examined the effect of the presence of thiamine pyrophosphate in the redox behavior of Fe{sup 2+}/Fe{sup 3+} at the pyrite surface. The results are described herein.

  18. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

    SciTech Connect

    Pesic, B.

    1990-01-01

    The present investigation is a part of our studies on the electrochemical aspects of pyrite bioleaching involving Thiobacillus ferrooxidans. Previously we have examined the effect of T. ferrooxidans and their metabolic products on the redox reactions of Fe{sup 2+}/Fe{sup 3+} couple at the pyrite surface. Results obtained suggest that beyond 1.5 days during their growth in a batch fermenter, the bacteria and their metabolic products completely cover the pyrite surface and shut down all electron transfer across the electrode-solution interface. In addition, it has been observed that the bacteria serve as the nucleation site for jarosite formation, which is found detrimental to bioleaching. In the present work we have focused on the effect of the presence of vitamins on the redox chemistry of iron. To date, we have examined the effect of the presence of thiamine hydrochloride in the redox behavior of Fe{sup 2+}/Fe{sup 3+} at the pyrite surface. The results are described herein.

  19. Leaching of Pyrites of Various Reactivities by Thiobacillus ferrooxidans.

    PubMed

    Baldi, F; Clark, T; Pollack, S S; Olson, G J

    1992-06-01

    Wide variations were found in the rate of chemical and microbiological leaching of iron from pyritic materials from various sources. Thiobacillus ferrooxidans accelerated leaching of iron from all of the pyritic materials tested in shake flask suspensions at loadings of 0.4% (wt/vol) pulp density. The most chemically reactive pyrites exhibited the fastest bioleaching rates. However, at 2.0% pulp density, a delay in onset of bioleaching occurred with two of the pyrites derived from coal sources. T. ferrooxidans was unable to oxidize the most chemically reactive pyrite at 2.0% pulp density. No inhibition of pyrite oxidation by T. ferrooxidans occurred with mineral pyrite at 2.0% pulp density. Experiments with the most chemically reactive pyrite indicated that the leachates from the material were not inhibitory to iron oxidation by T. ferrooxidans. PMID:16348718

  20. Leaching of Pyrites of Various Reactivities by Thiobacillus ferrooxidans

    PubMed Central

    Baldi, Franco; Clark, Thomas; Pollack, S. S.; Olson, Gregory J.

    1992-01-01

    Wide variations were found in the rate of chemical and microbiological leaching of iron from pyritic materials from various sources. Thiobacillus ferrooxidans accelerated leaching of iron from all of the pyritic materials tested in shake flask suspensions at loadings of 0.4% (wt/vol) pulp density. The most chemically reactive pyrites exhibited the fastest bioleaching rates. However, at 2.0% pulp density, a delay in onset of bioleaching occurred with two of the pyrites derived from coal sources. T. ferrooxidans was unable to oxidize the most chemically reactive pyrite at 2.0% pulp density. No inhibition of pyrite oxidation by T. ferrooxidans occurred with mineral pyrite at 2.0% pulp density. Experiments with the most chemically reactive pyrite indicated that the leachates from the material were not inhibitory to iron oxidation by T. ferrooxidans. PMID:16348718

  1. Leaching of pyrites of various reactivities by Thiobacillus ferrooxidans

    SciTech Connect

    Baldi, F. ); Clark, T.; Pollack, S.S.; Olson, G.J. )

    1992-06-01

    Variations were found in the rate of chemical and microbiological leaching of iron from pyritic materials from various sources. Thiobacillus ferrooxidans accelerated leaching of iron from all of the pyritic materials tested in shake flask suspensions at loadings of 0.4% (wt/vol) pulp density. The most chemically reactive pyrites exhibited the fastest bioleaching rates. However, at 2.0% pulp density, a delay in onset of bioleaching occurred with two of the pyrites derived from coal sources. T. ferrooxidans was unable to oxidize the most chemically reactive pyrite at 2.0% pulp density. No inhibition of pyrite oxidation by T. ferrooxidans occurred with mineral pyrite at 2.0% pulp density. Experiments with the most chemically reactive pyrite indicated that the leachates from the material were not inhibitory to iron oxidation by T. ferrooxidans.

  2. Existence of Two Kinds of Sulfur-reducing Systems in Iron-oxidizing Bacterium Thiobacillus ferrooxidans.

    PubMed

    Ng, K Y; Inoue, S; Fujioka, A; Kamimura, K; Sugio, T

    1999-01-01

    Intact cells of Thiobacillus ferrooxidans NASF-1 incubated under anaerobic conditions in a reaction mixture containing 0.5% colloidal sulfur produced hydrogen sulfide (H2S) extracellularly. The amount of H2S produced by cells increased corresponding to the cell amounts and colloidal sulfur. Two activity peaks of H2S production were observed at pH 1.5 and 7.5. We tentatively called the enzyme activities pH 1.5- and pH 7.5-sulfur reducing systems, respectively. Seven strains of T. ferrooxidans tested had both the activities of pH 1.5- and pH 7.5-sulfur reducing systems, but at different levels. T. ferrooxidans NASF-1 showed the highest activity of the pH 1.5-sulfur reducing system and strain 13598 from ATCC showed the highest activity of the pH 7.5-sulfur reducing system. Further characteristics of H2S production were studied with intact cells of NASF-1. The optimum temperatures for pH 1.5- and pH 7.5-sulfur reducing systems of NASF-1 were 40°C. Hydrogen sulfide production continued for 8 days and total amounts of H2S produced at pH 7.5 and 1.5 were 832 and 620 nmol/mg protein, respectively. The pH 7.5-sulfur reducing system used only colloidal sulfur as the electron acceptor. However, the pH 1.5-sulfur reducing system used both colloidal sulfur and tetrathionate. Thiosulfate, dithionate, and sulfite could not be used as the electron acceptor for both of the sulfur reducing systems. Potassium cyanide activated by 3- fold the pH 1.5-sulfur reducing system activity at 0.5 mM but did not affect the activity of the pH 7.5-sulfur reducing system. An inhibitor of sulfite reductase, p-chloromercuribenzene sulfonic acid, did not affect either enzyme activity. Sodium molybdate and monoiodoacetic acid strongly inhibited the activity of the pH 1.5-sulfur reducing system at 1.0 mM, but not the activity of pH 7.5-sulfur reducing system. PMID:27385566

  3. [Oxidation of sulfide minerals by Thiobacillus ferrooxidans].

    PubMed

    Malakhova, P T; Chebotarev, G M; Kovalenko, E V; Volkov, Iu A

    1981-01-01

    Samples of natural pyrites and sphalerites were subjected to the action of the mineral medium 9K with 1 g of Fe3+ per litre in the presence and in the absence of Thiobacillus ferrooxidans, and incubated at 28 degrees C under the stationary conditions for 30 days. The chemical composition of the solutions was studied after leaching as well as changes of the surfaces of monoliths. The deepest etching of surfaces with the formation of crusts and films of jarosite, limonite and goslarite occurs upon the combined action of bacteria and Fe3+ in regions of a fine-zonal structure enriched with an isomorphous arsenic admixture which are characterized by a defective weak structure. The pyrite and sphalerite from Charmitan with a higher arsenic and iron content were leached more than the pyrite and sphalerite from Kurgashincan. This was also corroborated by chemical analyses of leaching solutions and by monometric studies of crushed sulfide samples. PMID:7219212

  4. A new genome of Acidithiobacillus thiooxidans provides insights into adaptation to a bioleaching environment.

    PubMed

    Travisany, Dante; Cortés, María Paz; Latorre, Mauricio; Di Genova, Alex; Budinich, Marko; Bobadilla-Fazzini, Roberto A; Parada, Pilar; González, Mauricio; Maass, Alejandro

    2014-11-01

    Acidithiobacillus thiooxidans is a sulfur oxidizing acidophilic bacterium found in many sulfur-rich environments. It is particularly interesting due to its role in bioleaching of sulphide minerals. In this work, we report the genome sequence of At. thiooxidans Licanantay, the first strain from a copper mine to be sequenced and currently used in bioleaching industrial processes. Through comparative genomic analysis with two other At. thiooxidans non-metal mining strains (ATCC 19377 and A01) we determined that these strains share a large core genome of 2109 coding sequences and a high average nucleotide identity over 98%. Nevertheless, the presence of 841 strain-specific genes (absent in other At. thiooxidans strains) suggests a particular adaptation of Licanantay to its specific biomining environment. Among this group, we highlight genes encoding for proteins involved in heavy metal tolerance, mineral cell attachment and cysteine biosynthesis. Several of these genes were located near genetic motility genes (e.g. transposases and integrases) in genomic regions of over 10 kbp absent in the other strains, suggesting the presence of genomic islands in the Licanantay genome probably produced by horizontal gene transfer in mining environments. PMID:25148779

  5. Energy transduction by anaerobic ferric iron respiration in Thiobacillus ferrooxidans

    SciTech Connect

    Pronk, J.T.; Liem, K.; Bos, P.; Kuenen, J.G. )

    1991-07-01

    Formate-grown cells of the obligately chemolithoautotrophic acidophile Thiobacillus ferrooxidans were capable of formate- and elemental sulfur-dependent reduction of ferric iron under anaerovic conditions. Under aerobic conditions, both oxygen and ferric iron could be simultaneously used as electron acceptors. To investigate whether anaerobic ferric iron respiration by T. ferrooxidans is an energy-transducing process, uptake of amino acids was studied. Glycine uptake by starved cells did not occur in the absence of an electron donor, neither under aerobic conditions nor under anaerobic conditions. Uptake of glycine could be driven by formate- and ferrous iron-dependent oxygen uptake. Under anaerobic conditions, ferric iron respiration with the electron donors formate and elemental sulfur could energize glycine uptake. Glycine uptake was inhibited by the uncoupler 2,4-dinitrophenol. The results indicate that anaerobic ferric iron respiration can contribute to the energy budget of T. ferrooxidans.

  6. Complete genome sequence of Acidimicrobium ferrooxidans type strain (ICPT)

    SciTech Connect

    Clum, Alicia; Nolan, Matt; Lang, Elke; Glavina Del Rio, Tijana; Tice, Hope; Copeland, Alex; Cheng, Jan-Fang; Lucas, Susan; Chen, Feng; Bruce, David; Goodwin, Lynne; Pitluck, Sam; Ivanova, Natalia; Mavrommatis, Konstantinos; Mikhailova, Natalia; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Goker, Markus; Spring, Stefan; Land, Miriam; Hauser, Loren; Chang, Yun-Juan; Jefferies, Cynthia C.; Chain, Patrick; Bristow, James; Eisen, Jonathan A.; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C.; Klenk, Hans-Peter; Lapidus, Alla

    2009-05-20

    Acidimicrobium ferrooxidans (Clark and Norris 1996) is the sole and type species of the genus, which until recently was the only genus within the actinobacterial family Acidimicrobiaceae and in the order Acidomicrobiales. Rapid oxidation of iron pyrite during autotrophic growth in the absence of an enhanced CO2 concentration is characteristic for A. ferrooxidans. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the order Acidomicrobiales, and the 2,158,157 bp long single replicon genome with its 2038 protein coding and 54 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.

  7. Functional analysis of gapped microbial genomes: amino acid metabolism of Thiobacillus ferrooxidans.

    PubMed

    Selkov, E; Overbeek, R; Kogan, Y; Chu, L; Vonstein, V; Holmes, D; Silver, S; Haselkorn, R; Fonstein, M

    2000-03-28

    A gapped genome sequence of the biomining bacterium Thiobacillus ferrooxidans strain ATCC23270 was assembled from sheared DNA fragments (3.2-times coverage) into 1,912 contigs. A total of 2,712 potential genes (ORFs) were identified in 2.6 Mbp (megabase pairs) of Thiobacillus genomic sequence. Of these genes, 2,159 could be assigned functions by using the WIT-Pro/EMP genome analysis system, most with a high degree of certainty. Nine hundred of the genes have been assigned roles in metabolic pathways, producing an overview of cellular biosynthesis, bioenergetics, and catabolism. Sequence similarities, relative gene positions on the chromosome, and metabolic reconstruction (placement of gene products in metabolic pathways) were all used to aid gene assignments and for development of a functional overview. Amino acid biosynthesis was chosen to demonstrate the analytical capabilities of this approach. Only 10 expected enzymatic activities, of the nearly 150 involved in the biosynthesis of all 20 amino acids, are currently unassigned in the Thiobacillus genome. This result compares favorably with 10 missing genes for amino acid biosynthesis in the complete Escherichia coli genome. Gapped genome analysis can therefore give a decent picture of the central metabolism of a microorganism, equivalent to that of a complete sequence, at significantly lower cost. PMID:10737802

  8. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite. Final report

    SciTech Connect

    Pesic, B.; Oliver, D.J.; Kim, Inbeum; De, G.C.

    1993-01-20

    A cyclic voltammetry technique was used to study the interactions of pyrite during bioleaching with the bacterium Thiobacillus ferrooxidans. Potential effects of heavy metals (silver and mercury) and varying the pH on the iron oxidizing ability of the bacterium are reported. Redox potential techniques were used to study effect of ferrous sulfate concentration and pH on bacterial growth.

  9. Biological effect of Acidithiobacillus thiooxidans on some potentially toxic elements during alteration of SON 68 nuclear glass

    NASA Astrophysics Data System (ADS)

    Bachelet, M.; Crovisier, J. L.; Stille, P.; Vuilleumier, S.; Geoffroy, V.

    2009-04-01

    Although underground nuclear waste repositories are not expected to be favourable places for microbial activity, one should not exclude localized action of extremophilic bacteria on some materials involved in the storage concept. Among endogenous or accidentally introduced acidophiles, some are susceptible to lead to a locally drastic decreased in pH, with potential consequences on materials corrosion. Experiments were performed with Acidithiobacillus thiooxidans on 100-125 m french reference nuclear glass SON68 grains in a mineral medium under static conditions during 60 days at 25degC. Growth medium was periodically renewed and analyzed by ICP-AES and ICP-MS spectrometry for both major, trace and ultra-trace elements. Biofilm formation was evidenced by confocal laser microscopy, staining DNA with ethidium bromide and exopolysaccharides with calcofluor white. Biofilm thickness around material grains exceeded 20 m under the chosen experimental conditions. It can be noticed that while numerous studies on biofilm formation upon interaction between Acidithiobacillus ferrooxidans and materials are found in the literature, evidence for biofilm formation is still scarce for the case of the acidophilic bacterium A. thiooxidans. Presence of biofilm is a key parameter for material alteration at the solid/solution interface in biotic systems. Indeed, various constitutive elements of materials trapped in the polyanionic polymer of biofilm may also influence the alteration process. In particular, biofilm may reduce the alteration rate of materials by forming a protective barrier at their surface (Aouad et al., 2008). In this study, glass alteration rates, determined using strontium as tracer, showed that the progressive formation of a biofilm on the surface of glass has a protective effect against its alteration. Uranium and rare earth elements (REE) are efficiently trapped in the biogenic compartment of the system (exopolysaccharides + bacterial cells). Besides, the ratio

  10. Expression of Heterogenous Arsenic Resistance Genes in the Obligately Autotrophic Biomining Bacterium Thiobacillus ferrooxidans.

    PubMed

    Peng, J B; Yan, W M; Bao, X Z

    1994-07-01

    Two arsenic-resistant plasmids were constructed and introduced into Thiobacillus ferrooxidans strains by conjugation. The plasmids with the replicon of wide-host-range plasmid RSF1010 were stable in T. ferrooxidans. The arsenic resistance genes originating from the heterotroph were expressed in this obligately autotrophic bacterium, but the promoter derived from T. ferrooxidans showed no special function in its original host. PMID:16349341

  11. Acidithiobacillus caldus Sulfur Oxidation Model Based on Transcriptome Analysis between the Wild Type and Sulfur Oxygenase Reductase Defective Mutant

    PubMed Central

    Chen, Linxu; Ren, Yilin; Lin, Jianqun; Liu, Xiangmei; Pang, Xin; Lin, Jianqiang

    2012-01-01

    Background Acidithiobacillus caldus (A. caldus) is widely used in bio-leaching. It gains energy and electrons from oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs) for carbon dioxide fixation and growth. Genomic analyses suggest that its sulfur oxidation system involves a truncated sulfur oxidation (Sox) system (omitting SoxCD), non-Sox sulfur oxidation system similar to the sulfur oxidation in A. ferrooxidans, and sulfur oxygenase reductase (SOR). The complexity of the sulfur oxidation system of A. caldus generates a big obstacle on the research of its sulfur oxidation mechanism. However, the development of genetic manipulation method for A. caldus in recent years provides powerful tools for constructing genetic mutants to study the sulfur oxidation system. Results An A. caldus mutant lacking the sulfur oxygenase reductase gene (sor) was created and its growth abilities were measured in media using elemental sulfur (S0) and tetrathionate (K2S4O6) as the substrates, respectively. Then, comparative transcriptome analysis (microarrays and real-time quantitative PCR) of the wild type and the Δsor mutant in S0 and K2S4O6 media were employed to detect the differentially expressed genes involved in sulfur oxidation. SOR was concluded to oxidize the cytoplasmic elemental sulfur, but could not couple the sulfur oxidation with the electron transfer chain or substrate-level phosphorylation. Other elemental sulfur oxidation pathways including sulfur diooxygenase (SDO) and heterodisulfide reductase (HDR), the truncated Sox pathway, and the S4I pathway for hydrolysis of tetrathionate and oxidation of thiosulfate in A. caldus are proposed according to expression patterns of sulfur oxidation genes and growth abilities of the wild type and the mutant in different substrates media. Conclusion An integrated sulfur oxidation model with various sulfur oxidation pathways of A. caldus is proposed and the features of this model are summarized. PMID:22984393

  12. Detection of Thiobacillus ferrooxidans in acid mine environments by indirect fluorescent antibody staining.

    PubMed

    Apel, W A; Dugan, P R; Filppi, J A; Rheins, M S

    1976-07-01

    An indirect fluorescent antibody (FA) staining technique was developed for the rapid detection of Thiobacillus ferrooxidans. The specificity of the FA stain for T. ferrooxidans was demonstrated with both laboratory and environmental samples. Coal refuse examined by scanning electron microscopy exhibited a rough, porous surface, which was characteristically covered by water-soluble crystals. Significant numbers of T. ferrooxidans were detected in the refuse pores. A positive correlation between numbers of T. ferrooxidans and acid production in coal refuse in the laboratory was demonstrated with the FA technique. PMID:61736

  13. Architecture and Gene Repertoire of the Flexible Genome of the Extreme Acidophile Acidithiobacillus caldus

    PubMed Central

    Acuña, Lillian G.; Cárdenas, Juan Pablo; Covarrubias, Paulo C.; Haristoy, Juan José; Flores, Rodrigo; Nuñez, Harold; Riadi, Gonzalo; Shmaryahu, Amir; Valdés, Jorge; Dopson, Mark; Rawlings, Douglas E.; Banfield, Jillian F.; Holmes, David S.; Quatrini, Raquel

    2013-01-01

    Background Acidithiobacillus caldus is a sulfur oxidizing extreme acidophile and the only known mesothermophile within the Acidithiobacillales. As such, it is one of the preferred microbes for mineral bioprocessing at moderately high temperatures. In this study, we explore the genomic diversity of A. caldus strains using a combination of bioinformatic and experimental techniques, thus contributing first insights into the elucidation of the species pangenome. Principal Findings Comparative sequence analysis of A. caldus ATCC 51756 and SM-1 indicate that, despite sharing a conserved and highly syntenic genomic core, both strains have unique gene complements encompassing nearly 20% of their respective genomes. The differential gene complement of each strain is distributed between the chromosomal compartment, one megaplasmid and a variable number of smaller plasmids, and is directly associated to a diverse pool of mobile genetic elements (MGE). These include integrative conjugative and mobilizable elements, genomic islands and insertion sequences. Some of the accessory functions associated to these MGEs have been linked previously to the flexible gene pool in microorganisms inhabiting completely different econiches. Yet, others had not been unambiguously mapped to the flexible gene pool prior to this report and clearly reflect strain-specific adaption to local environmental conditions. Significance For many years, and because of DNA instability at low pH and recurrent failure to genetically transform acidophilic bacteria, gene transfer in acidic environments was considered negligible. Findings presented herein imply that a more or less conserved pool of actively excising MGEs occurs in the A. caldus population and point to a greater frequency of gene exchange in this econiche than previously recognized. Also, the data suggest that these elements endow the species with capacities to withstand the diverse abiotic and biotic stresses of natural environments, in particular

  14. Draft Genome Sequences of Rhodosporidium toruloides Strains ATCC 10788 and ATCC 10657 with Compatible Mating Types

    PubMed Central

    Hu, Jie

    2016-01-01

    Rhodosporidium toruloides ATCC 10788 (haploid, A1 mating type) and ATCC 10657 (haploid, A2 mating type) were derived from the same diploid parent strain Rhodotorula glutinis ATCC 90781 and are important strains for metabolic engineering. Draft genome sequences of both strains are reported here. The current assembly of strain ATCC 10788 comprises 61 scaffolds with a total size of 20.75 Mbp and a GC content of 62.01%, while that of strain ATCC 10657 comprises 137 scaffolds with a total size of 21.49 Mbp and a GC content of 61.81%. Genome annotation predicts 7,730 and 7,800 protein encoding genes for strain ATCC 10788 and strain ATCC 10657, respectively. PMID:26966203

  15. Draft Genome Sequences of Rhodosporidium toruloides Strains ATCC 10788 and ATCC 10657 with Compatible Mating Types.

    PubMed

    Hu, Jie; Ji, Lianghui

    2016-01-01

    Rhodosporidium toruloides ATCC 10788 (haploid, A1 mating type) and ATCC 10657 (haploid, A2 mating type) were derived from the same diploid parent strain Rhodotorula glutinis ATCC 90781 and are important strains for metabolic engineering. Draft genome sequences of both strains are reported here. The current assembly of strain ATCC 10788 comprises 61 scaffolds with a total size of 20.75 Mbp and a GC content of 62.01%, while that of strain ATCC 10657 comprises 137 scaffolds with a total size of 21.49 Mbp and a GC content of 61.81%. Genome annotation predicts 7,730 and 7,800 protein encoding genes for strain ATCC 10788 and strain ATCC 10657, respectively. PMID:26966203

  16. Importance of Extracellular Polymeric Substances from Thiobacillus ferrooxidans for Bioleaching

    PubMed Central

    Gehrke, Tilman; Telegdi, Judit; Thierry, Dominique; Sand, Wolfgang

    1998-01-01

    Leaching bacteria such as Thiobacillus ferrooxidans attach to pyrite or sulfur by means of extracellular polymeric substances (EPS) (lipopolysaccharides). The primary attachment to pyrite at pH 2 is mediated by exopolymer-complexed iron(III) ions in an electrochemical interaction with the negatively charged pyrite surface. EPS from sulfur cells possess increased hydrophobic properties and do not attach to pyrite, indicating adaptability to the substrate or substratum. PMID:9647862

  17. Specific dot-immunobinding assay for detection and enumeration of Thiobacillus ferrooxidans

    SciTech Connect

    Arredondo, R.; Jerez, C.A. )

    1989-08-01

    A specific and very sensitive dot-immunobinding assay for the detection and enumeration of the bioleaching microorganism Thiobacillus ferrooxidans was developed. Nitrocellulose spotted with samples was incubated with polyclonal antisera against whole T. ferrooxidans cells and then in {sup 125}I-labeled protein A or {sup 125}I-labeled goat antirabbit immunoglobulin G; incubation was followed by autoradiography. Since a minimum of 10{sup 3} cells per dot could be detected, the method offers the possibility of simultaneous processing of numerous samples in a short time to monitor the levels of T. ferrooxidans in bioleaching operations.

  18. Biodegradation of the french reference nuclear glass SON 68 by Acidithiobacillus thiooxidans : protective effect of the biofilm,U and REE retention

    NASA Astrophysics Data System (ADS)

    Bachelet, M.; Crovisier, J.; Stille, P.; Boutin, R.; Vuilleumier, S.; Geoffroy, V.

    2008-12-01

    Although underground nuclear waste repositories are not expected to be favourable places for microbial activity, one should not exclude localized action of extremophilic bacteria on some materials involved in the storage concept. Among endogenous or accidentally introduced acidophiles, some are susceptible to lead to a locally drastic decreased in pH with potential consequences on materials corrosion. Experiments were performed with Acidithiobacillus thiooxidans on 100-125 μm french reference nuclear glass SON68 grains in a mineral medium under static conditions during 60 days at 25°C. Growth medium was periodically renewed and analyzed by ICP-AES and ICP-MS spectrometry for both major, traces and ultra-traces elements. Biofilm formation was evidenced by confocal laser microscopy, staining DNA with ethidium bromide and exopolysaccharides with calcofluor white. Biofilm thickness around material grains exceeded 20 μm under the chosen experimental conditions. It can be noticed that while numerous studies on biofilm formation upon interaction between Acidithiobacillus ferrooxidans and materials can be found in the literature, evidence for biofilm formation is still scarce for the case of the acidophilic bacterium A. thiooxidans. Presence of biofilm is a key parameter for material alteration at the solid/solution interface in biotic systems. Indeed, various constitutive elements of materials trapped in the polyanionic polymer of biofilm may also influence the alteration process. In particular, biofilm may reduce the alteration rate of materials by forming a protective barrier at their surface (Aouad et al., 2008). In this study, glass alteration rates, determined using strontium, molybdenum and caesium as tracers, showed that the biofilm has a protective effect against glass alteration. U and REE are efficiently trapped in the biogenic compartment of the system (exopolysaccharides (EPS) + bacterial cells). Biofilm analysis are in progress to determine whether these

  19. Diguanylate Cyclase Null Mutant Reveals That C-Di-GMP Pathway Regulates the Motility and Adherence of the Extremophile Bacterium Acidithiobacillus caldus

    PubMed Central

    Castro, Matías; Deane, Shelly M.; Ruiz, Lina; Rawlings, Douglas E.; Guiliani, Nicolas

    2015-01-01

    An understanding of biofilm formation is relevant to the design of biological strategies to improve the efficiency of the bioleaching process and to prevent environmental damages caused by acid mine/rock drainage. For this reason, our laboratory is focused on the characterization of the molecular mechanisms involved in biofilm formation in different biomining bacteria. In many bacteria, the intracellular levels of c-di-GMP molecules regulate the transition from the motile planktonic state to sessile community-based behaviors, such as biofilm development, through different kinds of effectors. Thus, we recently started a study of the c-di-GMP pathway in several biomining bacteria including Acidithiobacillus caldus. C-di-GMP molecules are synthesized by diguanylate cyclases (DGCs) and degraded by phosphodiesterases (PDEs). We previously reported the existence of intermediates involved in c-di-GMP pathway from different Acidithiobacillus species. Here, we report our work related to At. caldus ATCC 51756. We identified several putative-ORFs encoding DGC and PDE and effector proteins. By using total RNA extracted from At. caldus cells and RT-PCR, we demonstrated that these genes are expressed. We also demonstrated the presence of c-di-GMP by mass spectrometry and showed that genes for several of the DGC enzymes were functional by heterologous genetic complementation in Salmonella enterica serovar Typhimurium mutants. Moreover, we developed a DGC defective mutant strain (Δc1319) that strongly indicated that the c-di-GMP pathway regulates the swarming motility and adherence to sulfur surfaces by At. caldus. Together, our results revealed that At. caldus possesses a functional c-di-GMP pathway which could be significant for ores colonization during the bioleaching process. PMID:25689133

  20. Diguanylate cyclase null mutant reveals that C-Di-GMP pathway regulates the motility and adherence of the extremophile bacterium Acidithiobacillus caldus.

    PubMed

    Castro, Matías; Deane, Shelly M; Ruiz, Lina; Rawlings, Douglas E; Guiliani, Nicolas

    2015-01-01

    An understanding of biofilm formation is relevant to the design of biological strategies to improve the efficiency of the bioleaching process and to prevent environmental damages caused by acid mine/rock drainage. For this reason, our laboratory is focused on the characterization of the molecular mechanisms involved in biofilm formation in different biomining bacteria. In many bacteria, the intracellular levels of c-di-GMP molecules regulate the transition from the motile planktonic state to sessile community-based behaviors, such as biofilm development, through different kinds of effectors. Thus, we recently started a study of the c-di-GMP pathway in several biomining bacteria including Acidithiobacillus caldus. C-di-GMP molecules are synthesized by diguanylate cyclases (DGCs) and degraded by phosphodiesterases (PDEs). We previously reported the existence of intermediates involved in c-di-GMP pathway from different Acidithiobacillus species. Here, we report our work related to At. caldus ATCC 51756. We identified several putative-ORFs encoding DGC and PDE and effector proteins. By using total RNA extracted from At. caldus cells and RT-PCR, we demonstrated that these genes are expressed. We also demonstrated the presence of c-di-GMP by mass spectrometry and showed that genes for several of the DGC enzymes were functional by heterologous genetic complementation in Salmonella enterica serovar Typhimurium mutants. Moreover, we developed a DGC defective mutant strain (Δc1319) that strongly indicated that the c-di-GMP pathway regulates the swarming motility and adherence to sulfur surfaces by At. caldus. Together, our results revealed that At. caldus possesses a functional c-di-GMP pathway which could be significant for ores colonization during the bioleaching process. PMID:25689133

  1. Bioleaching of heavy metals from sewage sludge using Acidithiobacillus thiooxidans

    NASA Astrophysics Data System (ADS)

    Wen, Ye-Ming; Lin, Hong-Yan; Wang, Qing-Ping; Chen, Zu-Liang

    2010-11-01

    Acidithiobacillus thiooxidans was isolated from sewage sludge using the incubation in the Waksman liquor medium and the inoculation in Waksman solid plate. It was found that the optimum conditions of the bioleaching included solid concentration 2%, sulfur concentration 5 gṡL-1 and cell concentration 10%. The removal efficiency of Cr, Cu, Pb and Zh in sewage sludge, which was obtained from waste treatment plant, Jinshan, Fuzhou, was 43.65%, 96.24%, 41.61% and 96.50% in the period of 4˜10 days under the optimum conditions, respectively. After processing using the proposed techniques, the heavy metals in sewage sludge did meet the requirement the standards of nation.

  2. Genome sequence of Lactobacillus rhamnosus ATCC 8530.

    PubMed

    Pittet, Vanessa; Ewen, Emily; Bushell, Barry R; Ziola, Barry

    2012-02-01

    Lactobacillus rhamnosus is found in the human gastrointestinal tract and is important for probiotics. We became interested in L. rhamnosus isolate ATCC 8530 in relation to beer spoilage and hops resistance. We report here the genome sequence of this isolate, along with a brief comparison to other available L. rhamnosus genome sequences. PMID:22247527

  3. Genome Sequence of Propionibacterium acidipropionici ATCC 55737.

    PubMed

    Luna-Flores, Carlos H; Nielsen, Lars K; Marcellin, Esteban

    2016-01-01

    Propionibacterium acidipropionici produces propionic acid as its main fermentation product. Traditionally derived from fossil fuels, environmental and sustainable issues have revived the interest in producing propionic acid using biological resources. Here, we present the closed sequence of Propionibacterium acidipropionici ATCC 55737, an efficient propionic acid producer. PMID:27198010

  4. Draft Genome Assemblies of Proteus mirabilis ATCC 7002 and Proteus vulgaris ATCC 49132.

    PubMed

    Minogue, T D; Daligault, H E; Davenport, K W; Bishop-Lilly, K A; Bruce, D C; Chain, P S; Coyne, S R; Chertkov, O; Freitas, T; Frey, K G; Jaissle, J; Koroleva, G I; Ladner, J T; Palacios, G F; Redden, C L; Xu, Y; Johnson, S L

    2014-01-01

    The pleomorphic swarming bacilli of the genus Proteus are common human gut commensal organisms but also the causative agents of recurrent urinary tract infections and bacteremia. We sequenced and assembled the 3.99-Mbp genome of Proteus mirabilis ATCC 7002 (accession no. JOVJ00000000) and the 3.97-Mbp genome of Proteus vulgaris ATCC 49132 (accession no. JPIX00000000), both of which are commonly used reference strains. PMID:25342681

  5. Corrosion and Electrochemical Oxidation of a Pyrite by Thiobacillus ferrooxidans

    PubMed Central

    Mustin, C.; Berthelin, J.; Marion, P.; de Donato, P.

    1992-01-01

    The oxidation of a pure pyrite by Thiobacillus ferrooxidans is not really a constant phenomenon; it must be considered to be more like a succession of different steps which need characterization. Electrochemical studies using a combination of a platinum electrode and a specific pyrite electrode (packed-ground-pyrite electrode) revealed four steps in the bioleaching process. Each step can be identified by the electrochemical behavior (redox potentials) of pyrite, which in turn can be related to chemical (leachate content), bacterial (growth), and physical (corrosion patterns) parameters of the leaching process. A comparison of the oxidation rates of iron and sulfur indicated the nonstoichiometric bacterial oxidation of a pure pyrite in which superficial phenomena, aqueous oxidation, and deep crystal dissolution are successively involved. Images PMID:16348688

  6. Corrosion and electrochemical oxidation of a pyrite by Thiobacillus ferrooxidans

    SciTech Connect

    Mustin, C.; Berthelin, J. ); Marion, P.; Donato, P. de )

    1992-04-01

    The oxidation of a pure pyrite by Thiobacillus Ferrooxidans is not really a constant phenomenon; it must be considered to be more like a succession of different steps which need characterization. Electrochemical studies using a combination of a platinum electrode and a specific pyrite electrode (packed-ground-pyrite electrode) revealed four steps in the bioleaching process. Each step can be identified by the electrochemical behavior (redox potentials) of pyrite, which in turn can be related to chemical (leachate content), bacterial (growth), and physical (corrosion patterns) parameters of the leaching process. A comparison of the oxidation rates of iron and sulfur indicated the nonstoichiometric bacterial oxidation of a pure pyrite in which superficial phenomena, aqueous oxidation, and deep crystal dissolution are successively involved.

  7. Mineral Products of Pyrrhotite Oxidation by Thiobacillus ferrooxidans.

    PubMed

    Bhatti, T M; Bigham, J M; Carlson, L; Tuovinen, O H

    1993-06-01

    The biological leaching of pyrrhotite (Fe(1-x)S) by Thiobacillus ferrooxidans was studied to characterize the oxidation process and to identify the mineral weathering products. The process was biphasic in that an initial phase of acid consumption and decrease in redox potential was followed by an acid-producing phase and an increase in redox potential. Elemental S was one of the first products of pyrrhotite degradation detected by X-ray diffraction. Pyrrhotite oxidation also yielded K-jarosite [KFe(3)(SO(4))(2)(OH)(6)], goethite (alpha-FeOOH), and schwertmannite [Fe(8)O(8)(OH)(6)SO(4)] as solid-phase products. Pyrrhotite was mostly depleted after 14 days, whereas impurities in the form of pyrite (cubic FeS(2)) and marcasite (orthorhombic FeS(2)) accumulated in the leach residue. PMID:16348977

  8. Rate Equations and Kinetic Parameters of the Reactions Involved in Pyrite Oxidation by Thiobacillus ferrooxidans.

    PubMed

    Lizama, H M; Suzuki, I

    1989-11-01

    Rate equations and kinetic parameters were obtained for various reactions involved in the bacterial oxidation of pyrite. The rate constants were 3.5 muM Fe per min per FeS(2) percent pulp density for the spontaneous pyrite dissolution, 10 muM Fe per min per mM Fe for the indirect leaching with Fe, 90 muM O(2) per min per mg of wet cells per ml for the Thiobacillus ferrooxidans oxidation of washed pyrite, and 250 muM O(2) per min per mg of wet cells per ml for the T. ferrooxidans oxidation of unwashed pyrite. The K(m) values for pyrite concentration were similar and were 1.9, 2.5, and 2.75% pulp density for indirect leaching, washed pyrite oxidation by T. ferrooxidans, and unwashed pyrite oxidation by T. ferrooxidans, respectively. The last reaction was competitively inhibited by increasing concentrations of cells, with a K(i) value of 0.13 mg of wet cells per ml. T. ferrooxidans cells also increased the rate of Fe production from Fe plus pyrite. PMID:16348054

  9. Ferrous iron oxidation by Thiobacillus ferrooxidans: inhibition with benzoic acid, sorbic acid, and sodium lauryl sulfate

    SciTech Connect

    Onysko, S.J.; Kleinmann, R.L.P.; Erickson, P.M.

    1984-07-01

    Thiobacillus ferrooxidans promote indirect oxidation of pyrite through the catalysis of the oxidation of ferrous iron to ferric iron, which is an effective oxidant of pyrite. These bacteria also may catalyze direct oxidation of pyrite by oxygen. A number of organic compounds, under laboratory conditions, can apparently inhibit both the oxidation of ferrous iron to ferric iron by T. ferrooxidans and the weathering of pyritic material by mixed cultures of acid mine drainage microorganisms. In this study, benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

  10. Ferrous iron oxidation by Thiobacillus ferrooxidans: inhibition with benzoic acid, sorbic acid and sodium lauryl sulfate

    SciTech Connect

    Onysko, S.J.

    1984-07-01

    Acid mine drainage is formed by the weathering or oxidation of pyritic material exposed during coal mining. The rate of pyritic material oxidation can be greatly accelerated by certain acidophilic bacteria such as Thiobacillus ferrooxidans which catalyse the oxidation of ferrous to ferric iron. A number of organic compounds, under laboratory conditions, can apparently inhibit both the oxidation of ferrous to ferric iron by T. ferrooxidans and the weathering of pyritic material by mixed cultures of acid mine drainage micro-organisms. Sodium lauryl sulphate (SLS), an anionic surfactant has proved effective in this respect. Benzoic acid, sorbic acid and SLS at low concentrations, each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of T. ferrooxidans. The rate of chemical oxidation of ferrous iron in low pH, sterile, batch reactors was not substantially affected at the tested concentrations of any of the compounds.

  11. Interfacial activity and leaching patterns of Leptospirillum ferrooxidans on pyrite.

    PubMed

    Rojas-Chapana, José A; Tributsch, Helmut

    2004-01-01

    The leaching ability of Leptospirillum ferrooxidans goes beyond the mere oxidation of Fe(2+) to Fe(3+). Addition of these bacteria to pyrite triggers interfacial phenomena that lead to bacterial attachment and local forms of corrosion (surface pitting). As the leaching process proceeds, bacterial cells undergo changes, characterized by the release of extracellular polymeric substances (EPS) and the uptake and storage of electro-dense nanoparticles. The latter are embedded in an exopolymeric capsule, which coats the bacterial surface leading to distinctive biomineralized assemblages. High-resolution scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses, quantitative energy-dispersive X-ray measurements and electron diffraction established that the embedded electron-dense nanoparticles comprise pyrite with a well-defined stoichiometry. Addition of Fe(3+) alone did not induce any form of local corrosion on pyrite, which indicates that the reactions taking place between the attached bacteria and the underlying pyrite surface are responsible for the leaching patterns observed in this study. The observed corrosion process resembles that of 'electrochemical machining', because it uses a corrosion promoter, namely the locally concentrated Fe(3+) in the biofilm environment, formed by the attached cells. PMID:19712343

  12. Sulfur Metabolism in the Extreme Acidophile Acidithiobacillus Caldus

    PubMed Central

    Mangold, Stefanie; Valdés, Jorge; Holmes, David S.; Dopson, Mark

    2011-01-01

    Given the challenges to life at low pH, an analysis of inorganic sulfur compound (ISC) oxidation was initiated in the chemolithoautotrophic extremophile Acidithiobacillus caldus. A. caldus is able to metabolize elemental sulfur and a broad range of ISCs. It has been implicated in the production of environmentally damaging acidic solutions as well as participating in industrial bioleaching operations where it forms part of microbial consortia used for the recovery of metal ions. Based upon the recently published A. caldus type strain genome sequence, a bioinformatic reconstruction of elemental sulfur and ISC metabolism predicted genes included: sulfide–quinone reductase (sqr), tetrathionate hydrolase (tth), two sox gene clusters potentially involved in thiosulfate oxidation (soxABXYZ), sulfur oxygenase reductase (sor), and various electron transport components. RNA transcript profiles by semi quantitative reverse transcription PCR suggested up-regulation of sox genes in the presence of tetrathionate. Extensive gel based proteomic comparisons of total soluble and membrane enriched protein fractions during growth on elemental sulfur and tetrathionate identified differential protein levels from the two Sox clusters as well as several chaperone and stress proteins up-regulated in the presence of elemental sulfur. Proteomics results also suggested the involvement of heterodisulfide reductase (HdrABC) in A. caldus ISC metabolism. A putative new function of Hdr in acidophiles is discussed. Additional proteomic analysis evaluated protein expression differences between cells grown attached to solid, elemental sulfur versus planktonic cells. This study has provided insights into sulfur metabolism of this acidophilic chemolithotroph and gene expression during attachment to solid elemental sulfur. PMID:21687411

  13. Microbial treatment of sulfur-contaminated industrial wastes.

    PubMed

    Gómez-Ramírez, Marlenne; Zarco-Tovar, Karina; Aburto, Jorge; de León, Roberto García; Rojas-Avelizapa, Norma G

    2014-01-01

    The present study evaluated the microbial removal of sulfur from a solid industrial waste in liquid culture under laboratory conditions. The study involved the use of two bacteria Acidithiobacillus ferrooxidans ATCC 53987 and Acidithiobacillus thiooxidans AZCT-M125-5 isolated from a Mexican soil. Experimentation for industrial waste biotreatment was done in liquid culture using 125-mL Erlenmeyer flasks containing 30 mL Starkey modified culture medium and incubated at 30°C during 7 days. The industrial waste was added at different pulp densities (8.25-100% w/v) corresponding to different sulfur contents from 0.7 to 8.63% (w/w). Sulfur-oxidizing activity of the strain AZCT-M125-5 produced 281 and 262 mg/g of sulfate and a sulfur removal of 60% and 45.7% when the pulp density was set at 8.25 and 16.5% (w/v), respectively. In comparison, the strain A. ferrooxidans ATCC 53987 showed a lower sulfur-oxidizing activity with a sulfate production of 25.6 and 12.7 mg/g and a sulfur removal of 6% and 2.5% at the same pulp densities, respectively. Microbial growth was limited by pulp densities higher than 25% (w/v) of industrial waste with minimal sulfur-oxidizing activity and sulfur removal. The rate of sulfur removal for Acidithiobacillus thioxidans AZCT-M125-5 and Acidithiobacillus ferrooxidans ATCC 53987 was 0.185 and 0.0159 mg S g(-1) h(-1) with a pulp density of 16.5% (w/v), respectively. This study demonstrated that Acidithiobacillus thiooxidans AZCT-M125-5 possesses a high sulfur-oxidizing activity, even at high sulfur concentration, which allows the treatment of hazardous materials. PMID:24171423

  14. Proteomic Analysis of the Secretome of Cellulomonas fimi ATCC 484 and Cellulomonas flavigena ATCC 482

    PubMed Central

    Wakarchuk, Warren W.; Brochu, Denis; Foote, Simon; Robotham, Anna; Saxena, Hirak; Erak, Tamara; Kelly, John

    2016-01-01

    The bacteria in the genus Cellulomonas are known for their ability to degrade plant cell wall biomass. Cellulomonas fimi ATCC 484 and C. flavigena ATCC 482 have been the subject of much research into secreted cellulases and hemicellulases. Recently the genome sequences of both C. fimi ATCC 484 and C. flavigena ATCC 482 were published, and a genome comparison has revealed their full spectrum of possible carbohydrate-active enzymes (CAZymes). Using mass spectrometry, we have compared the proteins secreted by C. fimi and C. flavigena during growth on the soluble cellulose substrate, carboxymethylcellulose (CMC), as well as a soluble xylan fraction. Many known C. fimi CAZymes were detected, which validated our analysis, as were a number of new CAZymes and other proteins that, though identified in the genome, have not previously been observed in the secretome of either organism. Our data also shows that many of these are co-expressed on growth of either CMC or xylan. This analysis provides a new perspective on Cellulomonas enzymes and provides many new CAZyme targets for characterization. PMID:26950732

  15. Heterotrophic bacteria from cultures of autotrophic Thiobacillus ferrooxidans: relationships as studied by means of deoxyribonucleic acid homology.

    PubMed

    Harrison, A P; Jarvis, B W; Johnson, J L

    1980-07-01

    From several presumably pure cultures of Thiobacillus ferrooxidans, we isolated a pair of stable phenotypes. One was a strict autotroph utilizing sulfur or ferrous iron as the energy source and unable to utilize glucose; the other phenotype was an acidophilic obligate heterotroph capable of utilizing glucose but not sulfur or ferrous iron. The acidophilic obligate heterotroph not only was encountered in cultures of T. ferrooxidans, but also was isolated with glucose-mineral salts medium, pH 2.0, directly from coal refuse. By means of deoxyribonucleic acid homology, we have demonstrated that the acidophilic heterotrophs are of a different genotype from T. ferrooxidans, not closely related to this species; we have shown also that the acidophilic obligate heterotrophs, regardless of their source of isolation, are related to each other. Therefore, cultures of T. ferrooxidans reported capable of utilizing organic compounds should be carefully examined for contamination. The acidophilic heterotrophs isolated by us are different from T. acidophilis, which is also associated with T. ferrooxidans but is facultative, utilizing both glucose and elemental sulfur as energy sources. Since they are so common and tenacious in T. ferrooxidans cultures, the heterotrophs must be associated with T. ferrooxidans in the natural habitat. PMID:7400100

  16. Nucleotide sequence of the gene encoding the nitrogenase iron protein of Thiobacillus ferrooxidans

    SciTech Connect

    Pretorius, I.M.; Rawlings, D.E.; O'Neill, E.G.; Jones, W.A.; Kirby, R.; Woods, D.R.

    1987-01-01

    The DNA sequence was determined for the cloned Thiobacillus ferrooxidans nifH and part of the nifD genes. The DNA chains were radiolabeled with (..cap alpha..-/sup 32/P)dCTP (3000 Ci/mmol) or (..cap alpha..-/sup 35/S)dCTP (400 Ci/mmol). A putative T. ferrooxidans nifH promoter was identified whose sequences showed perfect consensus with those of the Klebsiella pneumoniae nif promoter. Two putative consensus upstream activator sequences were also identified. The amino acid sequence was deduced from the DNA sequence. In a comparison of nifH DNA sequences from T. ferrooxidans and eight other nitrogen-fixing microbes, a Rhizobium sp. isolated from Parasponia andersonii showed the greatest homology (74%) and Clostridium pasteurianum (nifH1) showed the least homology (54%). In the comparison of the amino acid sequences of the Fe proteins, the Rhizobium sp. and Rhizobium japonicum showed the greatest homology (both 86%) and C. pasteurianum (nifH1 gene product) demonstrated the least homology (56%) to the T. ferrooxidans Fe protein.

  17. Recent allopolyploid origin of Zygosaccharomyces rouxii strain ATCC 42981.

    PubMed

    Gordon, Jonathan L; Wolfe, Kenneth H

    2008-06-01

    Zygosaccharomyces rouxii strain ATCC 42981 has been reported to have two copies of several genes including HOG1 and SOD2, whereas the type strain of Z. rouxii (CBS 732) has only one. To investigate the structure of the ATCC 42981 genome we sequenced random fragments from this genome and compared the data to the type strain. We found that ATCC 42981 contains two versions of the ribosomal RNA array, one of which is identical in the ITS1-ITS2 and 26S D1/D2 regions to Z. rouxii CBS 732, while the other is almost identical to a species provisionally named Z. pseudorouxii. We found that most genomic regions from Z. rouxii CBS 732 map in a one-to-two fashion to pairs of regions in ATCC 42981, with one of the ATCC 42981 regions having 97-100% DNA sequence identity to CBS 732 and the other having about 80-90% identity. Complete sequencing of regions containing 30 pairs of genes from ATCC 42981 and their orthologues in CBS 732 showed no evidence of the gene deletions or pseudogene formation that might be expected if ATCC 42981 had undergone whole-genome duplication several million years ago and was in the early stages of gene loss. Instead, we conclude that ATCC 42981 is a Z. rouxii-Z. pseudorouxii interspecies hybrid that was formed so recently that its genome has not had time to decay. PMID:18509846

  18. Draft Genome Sequence of Type Strain Streptococcus gordonii ATCC 10558

    PubMed Central

    Rasmussen, Louise H.; Dargis, Rimtas; Skovgaard, Ole

    2016-01-01

    Streptococcus gordonii ATCC 10558T was isolated from a patient with infective endocarditis in 1946 and announced as a type strain in 1989. Here, we report the 2,154,510-bp draft genome sequence of S. gordonii ATCC 10558T. This sequence will contribute to knowledge about the pathogenesis of infective endocarditis. PMID:26893427

  19. Manganese transport in Brevibacterium ammoniagenes ATCC 6872.

    PubMed Central

    Schmid, J; Auling, G

    1987-01-01

    Uptake of manganese by Brevibacterium ammoniagenes ATCC 6872 was energy dependent and obeyed saturation kinetics (Km = 0.65 microM; Vmax = 0.12 mumol/min per g [dry weight]). Uptake showed optima at 27 degrees C and pH 9.5. 54Mn2+ accumulated by the cells was released by treatment with toluene or by exchange for unlabeled manganese ions, via an energy-dependent process. Co2+, Fe2+, Cd2+, and Zn2+ inhibited manganese uptake. Inhibition by Cd2+ and Zn2+ was competitive (Ki = 0.15 microM Cd2+ and 1.2 microM Zn2+). Experiments with 65Zn2+ provided no evidence for Zn2+ uptake via the Mn2+ transport system. PMID:3597325

  20. [Recent research progress on the biomining bacteria of Acidithiobacillus caldus--a review].

    PubMed

    Pang, Xin; Chen, Dandan; Lin, Jianqun; Liu, Xiangmei; Lin, Jianqiang; Yan, Wangming

    2009-11-01

    Acidithiobacillus caldus (A. caldus) is one of the predominant biomining bacteria, which shows application prospect in biological metallurgy. It can enhance the biomining efficiency together with iron oxidation bacteria in mixed biomining system. Based on the published papers and our study on this bacterium, we described the research progress on it from four aspects, including the biomining mechanism, arsenic-resistant mechanism, genome study and genetic reconstruction. Furthermore, we discussed the prospects of research on A. caldus. PMID:20112666

  1. Detection, identification and typing of Acidithiobacillus species and strains: a review.

    PubMed

    Nuñez, Harold; Covarrubias, Paulo C; Moya-Beltrán, Ana; Issotta, Francisco; Atavales, Joaquín; Acuña, Lillian G; Johnson, D Barrie; Quatrini, Raquel

    2016-09-01

    The genus Acidithiobacillus comprises several species of Gram-negative acidophilic bacteria that thrive in natural and man-made low pH environments in a variety of geo-climatic contexts. Beyond their fundamental interest as model extreme acidophiles, these bacteria are involved in the processing of minerals and the desulfurization of coal and natural gas, and are also sources of environmental pollution due to their generation of acid mine drainage and corrosion of cement and concrete structures. Acidithiobacillus spp. are therefore considered a biotechnologically relevant group of bacteria, and their identification and screening in natural and industrial environments is of great concern. Several molecular typing methodologies have been instrumental in improving knowledge of the inherent diversity of acidithiobacilli by providing information on the genetic subtypes sampled in public and private culture collections; more recently, they have provided specific insight into the diversity of acidithiobacilli present in industrial and natural environments. The aim of this review is to provide an overview of techniques used in molecular detection, identification and typing of Acidithiobacillus spp. These methods will be discussed in the context of their contribution to the general and specific understanding of the role of the acidithiobacilli in microbial ecology and industrial biotechnology. Emerging opportunities for industrial and environmental surveillance of acidithiobacilli using next-generation molecular typing methodologies are also reviewed. PMID:27288569

  2. Draft Genome Sequence of Mycobacterium brumae ATCC 51384

    PubMed Central

    D'Auria, Giuseppe

    2016-01-01

    Here, we report the draft genome sequence of Mycobacterium brumae type strain ATCC 51384. This is the first draft genome sequence of M. brumae, a nonpathogenic, rapidly growing, nonchromogenic mycobacterium, with immunotherapeutic capacities. PMID:27125480

  3. Genome Sequence of Streptomyces aureofaciens ATCC Strain 10762

    PubMed Central

    Gradnigo, Julien S.; Somerville, Greg A.; Huether, Michael J.; Kemmy, Richard J.; Johnson, Craig M.; Oliver, Michael G.

    2016-01-01

    Streptomyces aureofaciens is a Gram-positive actinomycete that produces the antibiotics tetracycline and chlortetracycline. Here, we report the assembly and initial annotation of the draft genome sequence of S. aureofaciens ATCC strain 10762. PMID:27340076

  4. Genome sequence of the fish pathogen Flavobacterium columnare ATCC 49512

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavobacterium columnare is a Gram-negative, rod shaped, motile, and highly prevalent fish pathogen causing columnaris disease in freshwater fish worldwide. Here, we present the complete genome sequence of F. columnare strain ATCC 49512. ...

  5. Gene function analysis in extremophiles: the "nif" regulon of the strict iron oxidizing bacterium "Leptospirillum ferrooxidans"

    NASA Astrophysics Data System (ADS)

    Parro, Victor; Moreno-Paz, Mercedes

    2004-03-01

    In Centro de Astrobiologia it has been considered the Tinto river as a model ecosystem to study life based on iron. The final goal is to study the biological and metabolic diversity in microorganisms living there, following a genomic approach, to get insights to the mechanisms of adaptation to this environment. The Gram-negative bacterium Leptospirillum ferrooxidans is one of the most abundant microorganisms in the river, and it is one of the main responsible in maintenance of pH balance and, as a consequence, the physico-chemical properties of the exosystem. We have constructed a Shotgun DNA microarrays from this bacterium and we have used it to studied its genetic capacity for nitrogen fixation. With this approach we have identified most of the genes necessary for dinitrogen (N2) reduction, confirming the capacity of L. ferrooxidans as a free diazotrophic (nitrogen fixer) microorganism.

  6. Bioleaching of pyrite by Thiobacillus ferrooxidans: fixed grains electrode to study superficial oxidized compounds

    NASA Astrophysics Data System (ADS)

    Toniazzo, Valérie; Lazaro, Isabelle; Humbert, Bernard; Mustin, Christian

    1999-04-01

    An electrode with fixed pyrite grains on a graphite and silicon paste has been used to study the electrochemical processes at the surface of powdered pyrite during bioleaching by Thiobacillus ferrooxidans. The study of an air-oxidized pyrite shows that the fixed grains electrode (FGE) is more sensitive than the classical Carbon Paste Electrode (CPE) already used by different authors to characterize various oxides and sulfurs. On the other hand, the concommitant Raman and electrochemical analysis of autoclaved pyrite shows that the cleaned mineral FeS 2 has no electrochemical reactivity, and points out that the electrochemical response of the oxidized mineral is exclusively due to the chemical compounds present at its surface. Therefore, the electrode acts as an efficient sensor for pyrite superficial oxidized phases, which are fundamental for the biooxidation process and is consequently very well adapted for the control of the oxidation state of pyrite powder during bioleaching by Thiobacillus ferrooxidans.

  7. An immunological strategy To monitor In situ the phosphate starvation state in thiobacillus ferrooxidans

    PubMed

    Varela; Levican; Rivera; Jerez

    1998-12-01

    Thiobacillus ferrooxidans is one of the chemolithoautotrophic bacteria important in industrial biomining operations. During the process of ore bioleaching, the microorganisms are subjected to several stressing conditions, including the lack of some essential nutrients, which can affect the rates and yields of bioleaching. When T. ferrooxidans is starved for phosphate, the cells respond by inducing the synthesis of several proteins, some of which are outer membrane proteins of high molecular weight (70,000 to 80,000). These proteins were considered to be potential markers of the phosphate starvation state of these microorganisms. We developed a single-cell immunofluorescence assay that allowed monitoring of the phosphate starvation condition of this biomining microorganism by measuring the increased expression of the surface proteins. In the presence of low levels of arsenate (2 mM), the growth of phosphate-starved T. ferrooxidans cells was greatly inhibited compared to that of control nonstarved cells. Therefore, the determination of the phosphorus nutritional state is particularly relevant when arsenic compounds are solubilized during the bioleaching of different ores. PMID:9835593

  8. Reclassification of Lactobacillus casei subsp. casei ATCC 393 and Lactobacillus rhamnosus ATCC 15820 as Lactobacillus zeae nom. rev., designation of ATCC 334 as the neotype of L. casei subsp. casei, and rejection of the name Lactobacillus paracasei.

    PubMed

    Dicks, L M; Du Plessis, E M; Dellaglio, F; Lauer, E

    1996-01-01

    The type strain of Lactobacillus casei subsp. casei (ATCC 393) exhibits low levels of DNA homology with other strains of L. casei subsp. casei (8 to 46%) and strains of Lactobacillus paracasei (30 to 50%), but exhibits a level of DNA similarity of 80% with Lactobacillus rhamnosus ATCC 15820, the original type strain of "Lactobacterium zeae" Kuznetsov 1959. Strains ATCC 393T (T = type strain) and ATCC 15820T are members of one protein profile cluster that is separate from the other Lactobacillus spp. The randomly amplified polymorphic DNA PCR profile of strain ATCC 393T is also different from the profiles obtained for the other species. L. casei ATCC 334T is genetically closely related to L. casei subsp. casei strains (71 to 97%) and L. paracasei strains (71 to 91%), is a member of the same protein profile cluster as these organisms, and shares several DNA amplicons with L. paracasei strains. On the basis of these results, we propose that L. casei subsp. casei ATCC 393T and L. rhamnosus ATCC 15820 should be reclassified as members of Lactobacillus zeae nom. rev. (type strain, ATCC 15820), that strain ATCC 334 should be designated the neotype strain of L. casei subsp. casei, and that the name L. paracasei should be rejected. PMID:8573516

  9. Effect of external pH perturbations on in vivo protein synthesis by the acidophilic bacterium Thiobacillus ferrooxidans.

    PubMed Central

    Amaro, A M; Chamorro, D; Seeger, M; Arredondo, R; Peirano, I; Jerez, C A

    1991-01-01

    The response of the obligate acidophilic bacterium Thiobacillus ferrooxidans to external pH changes is reported. When T. ferrooxidans cells grown at pH 1.5 were shifted to pH 3.5, there were several changes in the general protein synthesis pattern, including a large stimulation of the synthesis of a 36-kDa protein (p36). The apparent low isoelectric point of p36, its location in the membrane fraction, and its cross-reaction with anti-OmpC from Salmonella typhi suggested that it may be a porin whose expression is regulated by extracellular pH. Images PMID:1987171

  10. Draft Genome Sequence of the Extremophile Acidithiobacillus thiooxidans A01, Isolated from the Wastewater of a Coal Dump

    PubMed Central

    Yin, Huaqun; Zhang, Xian; Liang, Yili; Xiao, Yunhua; Niu, Jiaojiao

    2014-01-01

    The draft genome of Acidithiobacillus thiooxidans A01 contains 3,820,158 bp, with a G+C content of 53.08% and 3,660 predicted coding sequences (CDSs). The bacterium contains a series of specific genes involved in the oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs). PMID:24699951

  11. Missing Iron-Oxidizing Acidophiles Highly Sensitive to Organic Compounds

    PubMed Central

    Ueoka, Nagayoshi; Kouzuma, Atsushi; Watanabe, Kazuya

    2016-01-01

    The genus Acidithiobacillus includes iron-oxidizing lithoautotrophs that thrive in acidic mine environments. Acidithiobacillus ferrooxidans is a representative species and has been extensively studied for its application to the bioleaching of precious metals. In our attempts to cultivate the type strain of A. ferrooxidans (ATCC 23270T), repeated transfers to fresh inorganic media resulted in the emergence of cultures with improved growth traits. Strains were isolated from the resultant culture by forming colonies on inorganic silica-gel plates. A representative isolate (strain NU-1) was unable to form colonies on agarose plates and was more sensitive to organics, such as glucose, than the type strain of A. ferrooxidans. Strain NU-1 exhibited superior growth traits in inorganic iron media to those of other iron-oxidizing acidithiobacilli, suggesting its potential for industrial applications. A draft genome of NU-1 uncovered unique features in catabolic enzymes, indicating that this strain is not a mutant of the A. ferrooxidans type strain. Our results indicate that the use of inorganic silica-gel plates facilitates the isolation of as-yet-unexamined iron-oxidizing acidithiobacilli from environmental samples and enrichment cultures. PMID:27356527

  12. Examination of Lipopolysaccharide (O-Antigen) Populations of Thiobacillus ferrooxidans from Two Mine Tailings

    PubMed Central

    Southam, G.; Beveridge, T. J.

    1993-01-01

    Net acid-generating capacities of 39.74 kg of H2SO4 per ton (ca. 0.05 kg/kg) (pH 2.68) for the Lemoine copper mine tailings (closed ca. 8 years ago; located 40 km west of Chibougamau, Quebec, Canada) and 16.07 kg of H2SO4 per ton (ca. 0.02 kg/kg) (pH 3.01) for the Copper Rand tailings (in current use and 50 km distant [east] from those of Lemoine) demonstrate that these sulfide tailings can support populations of acidophilic thiobacilli. Oxidized regions in both tailings environments were readily visible, were extremely acidic (Lemoine, pH 2.36; Copper Rand, pH 3.07), and provided natural isolates for our study. A 10% (wt/vol) oxalic acid treatment, which solubilizes both ferric sulfate and ferric hydroxide precipitates (B. Ramsay, J. Ramsay, M. deTremblay, and C. Chavarie, Geomicrobiol. J. 6:171-177, 1988), enabled the recovery of intact bacterial cells from the tailings material and from liquid synthetic medium for lipopolysaccharide analysis. No viable cells could be cultured after this oxalic acid treatment. Sodium dodecyl sulfate-polyacrylamide gel electro-phoretic profiles of lipopolysaccharides extracted from the Lemoine tailings were complex, indicating a heterogeneous population of Thiobacillus ferrooxidans. Six T. ferrooxidans subspecies as identified by lipopolysaccharide analysis (i.e., lipopolysaccharide chemotypes) were eventually isolated from a total of 112 cultures from the Lemoine tailings. Using the same isolate and lipopolysaccharide typing techniques, we identified only a single lipopolysaccharide chemotype from 20 cultures of T. ferrooxidans isolated from the Copper Rand tailings. This homogeneity of lipopolysaccharide chemotype was much different from what was found for the older Lemoine tailings and may reflect a progressive lipopolysaccharide heterogeneity of Thiobacillus isolates as tailings leach and age. Images PMID:16348925

  13. Thermodynamic and kinetic characterization using process dynamics: acidophilic ferrous iron oxidation by Leptospirillum ferrooxidans.

    PubMed

    Kleerebezem, Robbert; van Loosdrecht, Mark C M

    2008-05-01

    Kinetic and stoichiometric properties of acidophilic aerobic ferrous iron oxidation by growing and non-growing Leptospirillum ferrooxidans cultures were investigated. The use of a continuous stirred tank reactor operated at a variable dilution rate and equipped with on-line measurement of the electron donor, acceptor and anabolic substrate uptake rate enabled detailed kinetic characterization from a single experiment. It was demonstrated that substrate conversion and microbial growth are tightly coupled processes in L. ferrooxidans, and uncoupling occurs only due to the minor impact of substrate conversion for growth-independent maintenance purposes. The tight stoichiometric coupling implies bioenergetic uncoupling of the catabolism and anabolism because the Gibbs energy change for ferrous iron oxidation as a function of the actual growth rate of the culture ranges from -45 to -25 kJ mol-FeII(-1). Bioenergetic description of the process could only be achieved by introduction of a growth rate dependent Gibbs energy dissipation term. Removal of carbon dioxide from the influent gas stopped biomass growth, but the biomass specific respiration rate was unaffected or slightly stimulated. The uncoupling of the catabolism and anabolism is suggested to induce instantaneously an energy dissipation pathway. Also dosage of a low concentration propionic acid resulted in complete inhibition of the anabolism. Propionic acid served as an uncoupler of the membrane potential and all catabolic energy is required for the increased maintenance requirements. Recovery of the anabolism after reestablishment of the normal cultivation conditions was obtained only after 1-2 days. The results obtained provide additional constraints on cultivation of L. ferrooxidans for biotechnological application. PMID:18080344

  14. Comparative Genomics of the Extreme Acidophile Acidithiobacillus thiooxidans Reveals Intraspecific Divergence and Niche Adaptation

    PubMed Central

    Zhang, Xian; Feng, Xue; Tao, Jiemeng; Ma, Liyuan; Xiao, Yunhua; Liang, Yili; Liu, Xueduan; Yin, Huaqun

    2016-01-01

    Acidithiobacillus thiooxidans known for its ubiquity in diverse acidic and sulfur-bearing environments worldwide was used as the research subject in this study. To explore the genomic fluidity and intraspecific diversity of Acidithiobacillus thiooxidans (A. thiooxidans) species, comparative genomics based on nine draft genomes was performed. Phylogenomic scrutiny provided first insights into the multiple groupings of these strains, suggesting that genetic diversity might be potentially correlated with their geographic distribution as well as geochemical conditions. While these strains shared a large number of common genes, they displayed differences in gene content. Functional assignment indicated that the core genome was essential for microbial basic activities such as energy acquisition and uptake of nutrients, whereas the accessory genome was thought to be involved in niche adaptation. Comprehensive analysis of their predicted central metabolism revealed that few differences were observed among these strains. Further analyses showed evidences of relevance between environmental conditions and genomic diversification. Furthermore, a diverse pool of mobile genetic elements including insertion sequences and genomic islands in all A. thiooxidans strains probably demonstrated the frequent genetic flow (such as lateral gene transfer) in the extremely acidic environments. From another perspective, these elements might endow A. thiooxidans species with capacities to withstand the chemical constraints of their natural habitats. Taken together, our findings bring some valuable data to better understand the genomic diversity and econiche adaptation within A. thiooxidans strains. PMID:27548157

  15. [Construction of an engineered Acidithiobacillus caldus with high-efficiency arsenic resistance].

    PubMed

    Zhao, Qing; Liu, Xiang-mei; Zhan, Yang; Lin, Jian-qun; Yan, Wang-ming; Bian, Jiang; Liu, Ying

    2005-10-01

    Using the recombinant technique in vitro, a new arsenic resistance plasmid pSDRA4 was constructed by subcloning the arsenic resistance genes from plasmid pUM3 into the wide-host-range IncQ plasmid pMMB24 with the hybrid trp-lac ( tac ) promoter, and followed by deleting the regulative gene of the promoter, the lacIQ gene. Then plasmid pSDRA4 was introduced from E. coli into extremely acidophilic obligately chemolithotrophic Acidithiobacillus caldus by conjugative transfer with a frequency of( 1.444 +/- 0.797) x 10(-4), and the engineered strain of Acidithiobacillus caldus (pSDRA4) for biomining was constructed. The successful transfer demonstrates the development of a conjugational system between strains of E. coli and A. caldus. The recombinant plasmid pSDRA4 is stable in A. caldus. Compared with wild type A. caldus, the level of the arsenic resistance of A. caldus (pSDRA4) is greatly raised from 10mmol/L to 45mmol/L. PMID:16342754

  16. RNA transcript sequencing reveals inorganic sulfur compound oxidation pathways in the acidophile Acidithiobacillus ferrivorans.

    PubMed

    Christel, Stephan; Fridlund, Jimmy; Buetti-Dinh, Antoine; Buck, Moritz; Watkin, Elizabeth L; Dopson, Mark

    2016-04-01

    Acidithiobacillus ferrivorans is an acidophile implicated in low-temperature biomining for the recovery of metals from sulfide minerals. Acidithiobacillus ferrivorans obtains its energy from the oxidation of inorganic sulfur compounds, and genes encoding several alternative pathways have been identified. Next-generation sequencing of At. ferrivorans RNA transcripts identified the genes coding for metabolic and electron transport proteins for energy conservation from tetrathionate as electron donor. RNA transcripts suggested that tetrathionate was hydrolyzed by the tetH1 gene product to form thiosulfate, elemental sulfur and sulfate. Despite two of the genes being truncated, RNA transcripts for the SoxXYZAB complex had higher levels than for thiosulfate quinone oxidoreductase (doxDAgenes). However, a lack of heme-binding sites in soxX suggested that DoxDA was responsible for thiosulfate metabolism. Higher RNA transcript counts also suggested that elemental sulfur was metabolized by heterodisulfide reductase (hdrgenes) rather than sulfur oxygenase reductase (sor). The sulfite produced as a product of heterodisulfide reductase was suggested to be oxidized by a pathway involving the sat gene product or abiotically react with elemental sulfur to form thiosulfate. Finally, several electron transport complexes were involved in energy conservation. This study has elucidated the previously unknown At. ferrivorans tetrathionate metabolic pathway that is important in biomining. PMID:26956550

  17. Acidithiobacillus ferriphilus sp. nov., a facultatively anaerobic iron- and sulfur-metabolizing extreme acidophile.

    PubMed

    Falagán, Carmen; Johnson, D Barrie

    2016-01-01

    The genus Acidithiobacillus includes three species that conserve energy from the oxidation of ferrous iron, as well as reduced sulfur, to support their growth. Previous work, based on multi-locus sequence analysis, identified a fourth group of iron- and sulfur-oxidizing acidithiobacilli as a potential distinct species. Eleven strains of 'Group IV' acidithiobacilli, isolated from different global locations, have been studied. These were all shown to be obligate chemolithotrophs, growing aerobically by coupling the oxidation of ferrous iron or reduced sulfur (but not hydrogen) to molecular oxygen, or anaerobically by the oxidation of reduced sulfur coupled to ferric iron reduction. All strains were mesophilic, although some were also psychrotolerant. Strain variation was also noted in terms of tolerance to extremely low pH and to elevated concentrations of transition metals. One strain was noted to display far greater tolerance to chloride than reported for other iron-oxidizing acidithiobacilli. All of the strains were able to catalyse the oxidative dissolution of pyrite and, on the basis of some of the combined traits of some of the strains examined, it is proposed that these may have niche roles in commercial mineral bioprocessing operations, such as for low temperature bioleaching of polysulfide ores in brackish waters. The name Acidithiobacillus ferriphilus sp. nov. is proposed to accommodate the strains described, with the type strain being M20T ( = DSM 100412T = JCM 30830T). PMID:26498321

  18. Comparative Genomics of the Extreme Acidophile Acidithiobacillus thiooxidans Reveals Intraspecific Divergence and Niche Adaptation.

    PubMed

    Zhang, Xian; Feng, Xue; Tao, Jiemeng; Ma, Liyuan; Xiao, Yunhua; Liang, Yili; Liu, Xueduan; Yin, Huaqun

    2016-01-01

    Acidithiobacillus thiooxidans known for its ubiquity in diverse acidic and sulfur-bearing environments worldwide was used as the research subject in this study. To explore the genomic fluidity and intraspecific diversity of Acidithiobacillus thiooxidans (A. thiooxidans) species, comparative genomics based on nine draft genomes was performed. Phylogenomic scrutiny provided first insights into the multiple groupings of these strains, suggesting that genetic diversity might be potentially correlated with their geographic distribution as well as geochemical conditions. While these strains shared a large number of common genes, they displayed differences in gene content. Functional assignment indicated that the core genome was essential for microbial basic activities such as energy acquisition and uptake of nutrients, whereas the accessory genome was thought to be involved in niche adaptation. Comprehensive analysis of their predicted central metabolism revealed that few differences were observed among these strains. Further analyses showed evidences of relevance between environmental conditions and genomic diversification. Furthermore, a diverse pool of mobile genetic elements including insertion sequences and genomic islands in all A. thiooxidans strains probably demonstrated the frequent genetic flow (such as lateral gene transfer) in the extremely acidic environments. From another perspective, these elements might endow A. thiooxidans species with capacities to withstand the chemical constraints of their natural habitats. Taken together, our findings bring some valuable data to better understand the genomic diversity and econiche adaptation within A. thiooxidans strains. PMID:27548157

  19. Microgravity Alters the Physiological Characteristics of Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895 under Different Nutrient Conditions

    PubMed Central

    Kim, H. W.; Matin, A.

    2014-01-01

    The aim of this study is to provide understanding of microgravity effects on important food-borne bacteria, Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895, cultured in nutrient-rich or minimal medium. Physiological characteristics, such as growth (measured by optical density and plating), cell morphology, and pH, were monitored under low-shear modeled microgravity (LSMMG; space conditions) and normal gravity (NG; Earth conditions). In nutrient-rich medium, all strains except ATCC 35150 showed significantly higher optical density after 6 h of culture under LSMMG conditions than under NG conditions (P < 0.05). LSMMG-cultured cells were approximately 1.8 times larger than NG-cultured cells at 24 h; therefore, it was assumed that the increase in optical density was due to the size of individual cells rather than an increase in the cell population. The higher pH of the NG cultures relative to that of the LSMMG cultures suggests that nitrogen metabolism was slower in the latter. After 24 h of culturing in minimal media, LSMMG-cultured cells had an optical density 1.3 times higher than that of NG-cultured cells; thus, the higher optical density in the LSMMG cultures may be due to an increase in both cell size and number. Since bacteria actively grew under LSMMG conditions in minimal medium despite the lower pH, it is of some concern that LSMMG-cultured E. coli O157:H7 may be able to adapt well to acidic environments. These changes may be caused by changes in nutrient metabolism under LSMMG conditions, although this needs to be demonstrated in future studies. PMID:24487539

  20. Occurrences at mineral-bacteria interface during oxidation of arsenopyrite by Thiobacillus ferrooxidans

    SciTech Connect

    Fernandez, M.G.M.; Mustin, C.; Berthelin, J.; Donato, P. de; Barres, O.; Marion, P.

    1995-04-05

    The combination of an improved bacterial desorption method, scanning electron microscopy (SEM), diffuse reflectance and transmission infrared Fourier transform spectroscopy, and a desorption-leaching device like high-pressure liquid chromatography (HPLC) was used to analyze bacterial populations and surface-oxidized phases during the arsenopyrite biooxidation by Thiobacillus ferrooxidans. The bacterial distribution, the physicochemical composition of the leachate, the evolution of corrosion patterns, and the nature and amount of the surface-oxidized chemical species characterized different behavior for each step of arsenopyrite bioleaching.

  1. Genome Sequence of Ureaplasma diversum Strain ATCC 49782.

    PubMed

    Marques, Lucas M; Guimarães, Ana M S; Martins, Hellen B; Rezende, Izadora S; Barbosa, Maysa S; Campos, Guilherme B; do Nascimento, Naíla C; Dos Santos, Andrea P; Amorim, Aline T; Santos, Verena M; Messick, Joanne B; Timenetsky, Jorge

    2015-01-01

    Here, we report the complete genome sequence of Ureaplasma diversum strain ATCC 49782. This species is of bovine origin, having an association with reproductive disorders in cattle, including placentitis, fetal alveolitis, abortion, and birth of weak calves. It has a small circular chromosome of 975,425 bp. PMID:25883297

  2. Draft Genome Sequence of Zymomonas mobilis ZM481 (ATCC 31823)

    PubMed Central

    Zhao, Ning; Pan, Yongxu

    2016-01-01

    Zymomonas mobilis ZM481 (ATCC 31823) is an ethanol-tolerant strain that can produce the highest level of ethanol in Z. mobilis from glucose in the shortest time. Here, we report a draft genome sequence of ZM481, which can help us understand the genes related to the ethanol tolerance of this strain. PMID:27056218

  3. Genome Assembly of Serratia marcescens Type Strain ATCC 13880.

    PubMed

    Daligault, H E; Davenport, K W; Minogue, T D; Broomall, S M; Bruce, D C; Chain, P S; Coyne, S R; Gibbons, H S; Jaissle, J; Rosenzweig, C N; Scholz, M; Teshima, H; Johnson, S L

    2014-01-01

    Serratia marcescens ATCC 13880 is the type strain of the species and a commonly used quality control strain. Here, we present the annotated genome assembly of 5.13 Mbp (59.8% G+C content) as submitted to NCBI under accession no. JOVM00000000. PMID:25291774

  4. Draft Genome Sequence of Alicyclobacillus acidoterrestris Strain ATCC 49025

    PubMed Central

    Pasvolsky, Ronit; Sela, Noa; Green, Stefan J.; Zakin, Varda

    2013-01-01

    Alicyclobacillus acidoterrestris is a spore-forming Gram-positive, thermo-acidophilic, nonpathogenic bacterium which contaminates commercial pasteurized fruit juices. The draft genome sequence for A. acidoterrestris strain ATCC 49025 is reported here, providing genetic data relevant to the successful adaptation and survival of this strain in its ecological niche. PMID:24009113

  5. 3-Methylindole production is regulated in Clostridium scatologenes ATCC 25775

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: 3-Methylindole (3-MI) is a degradation product of L-tryptophan and is both an animal waste malodorant and threat to ruminant health. Culture conditions which influence 3-MI production in Clostridium scatologenes ATCC 25775 were investigated. Methods and Results: Cells cultured in anaerobic ...

  6. Genome Sequence of the Oleaginous Yeast Rhodotorula glutinis ATCC 204091.

    PubMed

    Paul, Debarati; Magbanua, Zenaida; Arick, Mark; French, Todd; Bridges, Susan M; Burgess, Shane C; Lawrence, Mark L

    2014-01-01

    Rhodotorula glutinis ATCC 204091 is an oleaginous oxidative red yeast that can accumulate lipids to >50% of its biomass when grown with appropriate carbon and nitrogen ratios. It produces a red pigment consisting of useful antioxidants, such as carotenoids, torulene, and torularhodin, when cultivated under carbon-deficient conditions. PMID:24526636

  7. Draft Genome Sequence of Mycobacterium interjectum Strain ATCC 51457T

    PubMed Central

    Levasseur, Anthony; Asmar, Shady; Robert, Catherine

    2016-01-01

    Mycobacterium interjectum is a nontuberculosis species rarely responsible for human infection. The draft genome of M. interjectum ATCC 51457T comprises 5,927,979 bp, exhibiting 67.91% G+C content, 5,314 protein-coding genes, and 51 predicted RNA genes. PMID:27231376

  8. Complete genome sequence of Campylobacter gracilis ATCC 33236T

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The human oral pathogen Campylobacter gracilis has been isolated from periodontal and endodontal infections, and also from non-oral head, neck or lung infections. This study describes the whole-genome sequence of the human periodontal isolate ATCC 33236T (=FDC 1084), which is the first closed genome...

  9. Draft Genome Sequence of Alternaria alternata ATCC 34957.

    PubMed

    Nguyen, Hai D T; Lewis, Christopher T; Lévesque, C André; Gräfenhan, Tom

    2016-01-01

    We report the draft genome sequence of Alternaria alternata ATCC 34957. This strain was previously reported to produce alternariol and alternariol monomethyl ether on weathered grain sorghum. The genome was sequenced with PacBio technology and assembled into 27 scaffolds with a total genome size of 33.5 Mb. PMID:26769939

  10. Draft Genome Sequence of Rhodococcus rhodochrous Strain ATCC 21198

    SciTech Connect

    Shields-Menard, Sara A.; Brown, Steven D; Klingeman, Dawn Marie; Indest, Karl; Hancock, Dawn; Wewalwela, Jayani; French, Todd; Donaldson, Janet

    2014-01-01

    Rhodococcus rhodochrous is a Gram-positive red-pigmented bacterium commonly found in the soil. The draft genome sequence for R. rhodochrous strain ATCC 21198 is presented here to provide genetic data for a better understanding of its lipid-accumulating capabilities.

  11. Draft Genome Sequence of Mycobacterium houstonense Strain ATCC 49403T

    PubMed Central

    Levasseur, Anthony; Asmar, Shady; Robert, Catherine

    2016-01-01

    Mycobacterium houstonense is a nontuberculous species rarely responsible for human infection. The draft genome of M. houstonense ATCC 49403T comprises 6,451,020 bp, exhibiting a 66.96% G+C content, 5,881 protein-coding genes, and 65 predicted RNA genes. PMID:27231371

  12. Genome Assembly of Serratia marcescens Type Strain ATCC 13880

    PubMed Central

    Daligault, H. E.; Davenport, K. W.; Minogue, T. D.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Gibbons, H. S.; Jaissle, J.; Rosenzweig, C. N.; Scholz, M.; Teshima, H.

    2014-01-01

    Serratia marcescens ATCC 13880 is the type strain of the species and a commonly used quality control strain. Here, we present the annotated genome assembly of 5.13 Mbp (59.8% G+C content) as submitted to NCBI under accession no. JOVM00000000. PMID:25291774

  13. Draft Genome Sequence of Strain ATCC 33958, Reported To Be Elizabethkingia miricola

    PubMed Central

    Matyi, Stephanie A.; Hoyt, Peter R.; Ayoubi-Canaan, Patricia; Hasan, Nabeeh A.

    2015-01-01

    We report the draft genome of Elizabethkingia strain ATCC 33958, which has been classified as Elizabethkingia miricola. Similar to other Elizabethkingia species, the ATCC 33958 draft genome contains numerous β-lactamase genes. ATCC 33958 also harbors a urease gene cluster which supports classification as E. miricola. PMID:26205869

  14. 40 CFR 180.1205 - Beauveria bassiana ATCC #74040; exemption from the requirements of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Beauveria bassiana ATCC #74040... RESIDUES IN FOOD Exemptions From Tolerances § 180.1205 Beauveria bassiana ATCC #74040; exemption from the... the insecticide Beauveria bassiana (ATCC #74040) in or on all food commodities when applied or used...

  15. 40 CFR 180.1205 - Beauveria bassiana ATCC #74040; exemption from the requirements of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Beauveria bassiana ATCC #74040... RESIDUES IN FOOD Exemptions From Tolerances § 180.1205 Beauveria bassiana ATCC #74040; exemption from the... the insecticide Beauveria bassiana (ATCC #74040) in or on all food commodities when applied or used...

  16. Draft Genome Sequence of a Novel Acidophilic Iron-Oxidizing Firmicutes Species, "Acidibacillus ferrooxidans" (SLC66T).

    PubMed

    Ñancucheo, Ivan; Oliveira, Renato; Dall'Agnol, Hivana; Johnson, D Barrie; Grail, Barry; Holanda, Roseanne; Nunes, Gisele Lopes; Cuadros-Orellana, Sara; Oliveira, Guilherme

    2016-01-01

    Here, we present the draft genome sequence of the type strain of "Acidibacillus ferrooxidans," a mesophilic, heterotrophic, and acidophilic bacterium that was isolated from mine spoilage subjected to accelerated weathering in humidity cell tests carried out by the former U.S. Bureau of Mines in Salt Lake City, UT. PMID:27198020

  17. The oxidative dissolution of arsenopyrite (FeAsS) and enargite (Cu 3AsS 4) by Leptospirillum ferrooxidans

    NASA Astrophysics Data System (ADS)

    Corkhill, C. L.; Wincott, P. L.; Lloyd, J. R.; Vaughan, D. J.

    2008-12-01

    Arsenopyrite (FeAsS) and enargite (Cu 3AsS 4) fractured in a nitrogen atmosphere were characterised after acidic (pH 1.8), oxidative dissolution in both the presence and absence of the acidophilic microorganism Leptospirillum ferrooxidans. Dissolution was monitored through analysis of the coexisting aqueous solution using inductively coupled plasma atomic emission spectroscopy and coupled ion chromatography-inductively coupled plasma mass spectrometry, and chemical changes at the mineral surface observed using X-ray photoelectron spectroscopy and environmental scanning electron microscopy (ESEM). Biologically mediated oxidation of arsenopyrite and enargite (2.5 g in 25 ml) was seen to proceed to a greater extent than abiotic oxidation, although arsenopyrite oxidation was significantly greater than enargite oxidation. These dissolution reactions were associated with the release of ˜917 and ˜180 ppm of arsenic into solution. The formation of Fe(III)-oxyhydroxides, ferric sulphate and arsenate was observed for arsenopyrite, thiosulphate and an unknown arsenic oxide for enargite. ESEM revealed an extensive coating of an extracellular polymeric substance associated with the L. ferrooxidans cells on the arsenopyrite surface and bacterial leach pits suggest a direct biological oxidation mechanism, although a combination of indirect and direct bioleaching cannot be ruled out. Although the relative oxidation rates of enargite were greater in the presence of L. ferrooxidans, cells were not in contact with the surface suggesting an indirect biological oxidation mechanism. Cells of L. ferrooxidans appear able to withstand several hundreds of ppm of As(III) and As(V).

  18. Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

    PubMed

    Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

    2016-05-01

    In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. PMID:27049131

  19. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite. Technical progress report, Second quarter 1990

    SciTech Connect

    Pesic, B.

    1990-12-31

    The present investigation is a part of our studies on the electrochemical aspects of pyrite bioleaching involving Thiobacillus ferrooxidans. Previously we have examined the effect of T. ferrooxidans and their metabolic products on the redox reactions of Fe{sup 2+}/Fe{sup 3+} couple at the pyrite surface. Results obtained suggest that beyond 1.5 days during their growth in a batch fermenter, the bacteria and their metabolic products completely cover the pyrite surface and shut down all electron transfer across the electrode-solution interface. In addition, it has been observed that the bacteria serve as the nucleation site for jarosite formation, which is found detrimental to bioleaching. In the present work we have focused on the effect of the presence of vitamins on the redox chemistry of iron. To date, we have examined the effect of the presence of thiamine pyrophosphate in the redox behavior of Fe{sup 2+}/Fe{sup 3+} at the pyrite surface. The results are described herein.

  20. Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite. Technical progress report, Third quarter 1990

    SciTech Connect

    Pesic, B.

    1990-12-31

    The present investigation is a part of our studies on the electrochemical aspects of pyrite bioleaching involving Thiobacillus ferrooxidans. Previously we have examined the effect of T. ferrooxidans and their metabolic products on the redox reactions of Fe{sup 2+}/Fe{sup 3+} couple at the pyrite surface. Results obtained suggest that beyond 1.5 days during their growth in a batch fermenter, the bacteria and their metabolic products completely cover the pyrite surface and shut down all electron transfer across the electrode-solution interface. In addition, it has been observed that the bacteria serve as the nucleation site for jarosite formation, which is found detrimental to bioleaching. In the present work we have focused on the effect of the presence of vitamins on the redox chemistry of iron. To date, we have examined the effect of the presence of thiamine hydrochloride in the redox behavior of Fe{sup 2+}/Fe{sup 3+} at the pyrite surface. The results are described herein.

  1. Whole-genome sequencing reveals novel insights into sulfur oxidation in the extremophile Acidithiobacillus thiooxidans

    PubMed Central

    2014-01-01

    Background Acidithiobacillus thiooxidans (A. thiooxidans), a chemolithoautotrophic extremophile, is widely used in the industrial recovery of copper (bioleaching or biomining). The organism grows and survives by autotrophically utilizing energy derived from the oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs). However, the lack of genetic manipulation systems has restricted our exploration of its physiology. With the development of high-throughput sequencing technology, the whole genome sequence analysis of A. thiooxidans has allowed preliminary models to be built for genes/enzymes involved in key energy pathways like sulfur oxidation. Results The genome of A. thiooxidans A01 was sequenced and annotated. It contains key sulfur oxidation enzymes involved in the oxidation of elemental sulfur and RISCs, such as sulfur dioxygenase (SDO), sulfide quinone reductase (SQR), thiosulfate:quinone oxidoreductase (TQO), tetrathionate hydrolase (TetH), sulfur oxidizing protein (Sox) system and their associated electron transport components. Also, the sulfur oxygenase reductase (SOR) gene was detected in the draft genome sequence of A. thiooxidans A01, and multiple sequence alignment was performed to explore the function of groups of related protein sequences. In addition, another putative pathway was found in the cytoplasm of A. thiooxidans, which catalyzes sulfite to sulfate as the final product by phosphoadenosine phosphosulfate (PAPS) reductase and adenylylsulfate (APS) kinase. This differs from its closest relative Acidithiobacillus caldus, which is performed by sulfate adenylyltransferase (SAT). Furthermore, real-time quantitative PCR analysis showed that most of sulfur oxidation genes were more strongly expressed in the S0 medium than that in the Na2S2O3 medium at the mid-log phase. Conclusion Sulfur oxidation model of A. thiooxidans A01 has been constructed based on previous studies from other sulfur oxidizing strains and its genome sequence

  2. Diversity and ecophysiology of new isolates of extremely acidophilic CS2-converting Acidithiobacillus strains.

    PubMed

    Smeulders, Marjan J; Pol, Arjan; Zandvoort, Marcel H; Jetten, Mike S M; Op den Camp, Huub J M

    2013-11-01

    Biofiltration of industrial carbon disulfide (CS2)-contaminated waste air streams results in the acidification of biofilters and therefore reduced performance, high water use, and increased costs. To address these issues, we isolated 16 extremely acidophilic CS2-converting Acidithiobacillus thiooxidans strains that tolerated up to 6% (vol/vol) sulfuric acid. The ecophysiological properties of five selected strains (2Bp, Sts 4-3, S1p, G8, and BBW1) were compared. These five strains had pH optima between 1 (2Bp) and 2 (S1p). Their affinities for CS2 ranged between 80 (G8) and 130 (2Bp) μM. Strains S1p, G8, and BBW1 had more hydrophobic cell surfaces and produced less extracellular polymeric substance than did strains 2Bp and Sts 4-3. All five strains converted about 80% of the S added as CS2 to S(0) when CS2 was supplied in excess. The rate of S(0) consumption varied between 7 (Sts 4-3) and 63 (S1p) nmol O2 min(-1) ml culture(-1). Low S(0) consumption rates correlated partly with low levels of cell attachment to externally produced S(0) globules. During chemostat growth, the relative amount of CS2 hydrolase in the cell increased with decreasing growth rates. This resulted in more S(0) accumulation during CS2 overloads at low growth rates. Intermittent interruptions of the CS2 supply affected all five strains. Strains S1p, G8, and BBW1 recovered from 24 h of starvation within 4 h, and strains 2Bp and Sts 4-3 recovered within 24 h after CS2 was resupplied. We recommend the use of mixtures of Acidithiobacillus strains in industrial biofilters. PMID:23995926

  3. Diversity and Ecophysiology of New Isolates of Extremely Acidophilic CS2-Converting Acidithiobacillus Strains

    PubMed Central

    Smeulders, Marjan J.; Pol, Arjan; Zandvoort, Marcel H.; Jetten, Mike S. M.

    2013-01-01

    Biofiltration of industrial carbon disulfide (CS2)-contaminated waste air streams results in the acidification of biofilters and therefore reduced performance, high water use, and increased costs. To address these issues, we isolated 16 extremely acidophilic CS2-converting Acidithiobacillus thiooxidans strains that tolerated up to 6% (vol/vol) sulfuric acid. The ecophysiological properties of five selected strains (2Bp, Sts 4-3, S1p, G8, and BBW1) were compared. These five strains had pH optima between 1 (2Bp) and 2 (S1p). Their affinities for CS2 ranged between 80 (G8) and 130 (2Bp) μM. Strains S1p, G8, and BBW1 had more hydrophobic cell surfaces and produced less extracellular polymeric substance than did strains 2Bp and Sts 4-3. All five strains converted about 80% of the S added as CS2 to S0 when CS2 was supplied in excess. The rate of S0 consumption varied between 7 (Sts 4-3) and 63 (S1p) nmol O2 min−1 ml culture−1. Low S0 consumption rates correlated partly with low levels of cell attachment to externally produced S0 globules. During chemostat growth, the relative amount of CS2 hydrolase in the cell increased with decreasing growth rates. This resulted in more S0 accumulation during CS2 overloads at low growth rates. Intermittent interruptions of the CS2 supply affected all five strains. Strains S1p, G8, and BBW1 recovered from 24 h of starvation within 4 h, and strains 2Bp and Sts 4-3 recovered within 24 h after CS2 was resupplied. We recommend the use of mixtures of Acidithiobacillus strains in industrial biofilters. PMID:23995926

  4. Closed Genome Sequence of Clostridium pasteurianum ATCC 6013

    PubMed Central

    Rotta, Carlo; Poehlein, Anja; Schwarz, Katrin; McClure, Peter; Daniel, Rolf

    2015-01-01

    We report here the closed genome of Clostridium pasteurianum ATCC 6013, a saccharolytic, nitrogen-fixing, and spore-forming Gram-positive obligate anaerobe. The organism is of biotechnological interest due to the production of solvents (butanol and 1,3-propanediol) but can be associated with food spoilage. The genome comprises a total of 4,351,223 bp. PMID:25700419

  5. Thermostable purified endoglucanase II from Acidothermus cellulolyticus ATCC

    DOEpatents

    Adney, William S.; Thomas, Steven R.; Nieves, Rafael A.; Himmel, Michael E.

    1994-01-01

    A purified low molecular weight endoglucanase II from Acidothermus cellulolyticus (ATCC 43068) is disclosed. The endoglucanase is water soluble, possesses both C.sub.1, and C.sub.x types of enzyme activity, a high degree of stability toward heat, and exhibits optimum temperature activity at about 81.degree. C. at pH's from about 2 to about 9, and at a inactivation temperature of about 100.degree. C. at pH's from about 2 to about 9.

  6. Magnetic response in cultures of Streptococcus mutans ATCC-27607.

    PubMed

    Adamkiewicz, V W; Bassous, C; Morency, D; Lorrain, P; Lepage, J L

    1987-01-01

    Streptococcus mutans ATCC-27607 produces exopolysaccharides that adhere to glass. In the normal geomagnetic field about 50% more polysaccharide adhere preferentially to glass surfaces facing North as compared to South facing surfaces. Reversal of the direction of the magnetic field by 180 degrees produces a similar reversal in the direction of the preferential accumulation. Reduction of the field by 90% abolishes the preferential accumulation. PMID:3582582

  7. Thermostable purified endoglucanase II from Acidothermus cellulolyticus ATCC

    DOEpatents

    Adney, W.S.; Thomas, S.R.; Nieves, R.A.; Himmel, M.E.

    1994-11-22

    A purified low molecular weight endoglucanase II from Acidothermus cellulolyticus (ATCC 43068) is disclosed. The endoglucanase is water soluble, possesses both C[sub 1], and C[sub x] types of enzyme activity, a high degree of stability toward heat, and exhibits optimum temperature activity at about 81 C at pH's from about 2 to about 9, and at a inactivation temperature of about 100 C at pH's from about 2 to about 9. 9 figs.

  8. Production of hydrogen sulfide from tetrathionate by the iron-oxidizing bacterium Thiobacillus ferrooxidans NASF-1.

    PubMed

    Ng, K Y; Kamimura, K; Sugio, T

    2000-01-01

    When incubated under anaerobic conditions, five strains of Thiobacillus ferrooxidans tested produced hydrogen sulfide (H2S) from elemental sulfur at pH 1.5. However, among the strains, T. ferrooxidans NASF-1 and AP19-3 were able to use both elemental sulfur and tetrathionate as electron acceptors for H2S production at pH 1.5. The mechanism of H2S production from tetrathionate was studied with intact cells of strain NASF-1. Strain NASF-1 was unable to use dithionate, trithionate, or pentathionate as an electron acceptor. After 12 h of incubation under anaerobic conditions at 30 degrees C, 1.3 micromol of tetrathionate in the reaction mixture was decomposed, and 0.78 micromol of H2S and 0.6 micromol of trithionate were produced. Thiosulfate and sulfite were not detected in the reaction mixture. From these results, we propose that H2S is produced at pH 1.5 from tetrathionate by T. ferrooxidans NASF-1, via the following two-step reaction, in which AH2 represents an unknown electron donor in NASF-1 cells. Namely, tetrathionate is decomposed by tetrathionate-decomposing enzyme to give trithionate and elemental sulfur (S4O6(2-)-->S3O6(2-) + S(o), Eq. 1), and the elemental sulfur thus produced is reduced by sulfur reductase using electrons from AH2 to give H2S (S(o) + AH2-->H2S + A, Eq. 2). The optimum pH and temperature for H2S production from tetrathionate under argon gas were 1.5 and 30 degrees C, respectively. Under argon gas, the H2S production from tetrathionate stopped after 1 d of incubation, producing a total of 2.5 micromol of H2S/5 mg protein. In contrast, under H2 conditions, H2S production continued for 6 d, producing a total of 10.0 micromol of H2S/5 mg protein. These results suggest that electrons from H2 were used to reduce elemental sulfur produced as an intermediate to give H2S. Potassium cyanide at 0.5 mM slightly inhibited H2S production from tetrathionate, but increased that from elemental sulfur 3-fold. 2,4-Dinitrophenol at 0.05 mM, carbonylcyanide

  9. Cellulose produced by Gluconacetobacter xylinus strains ATCC 53524 and ATCC 23768: Pellicle formation, post-synthesis aggregation and fiber density.

    PubMed

    Lee, Christopher M; Gu, Jin; Kafle, Kabindra; Catchmark, Jeffrey; Kim, Seong H

    2015-11-20

    The pellicle formation, crystallinity, and bundling of cellulose microfibrils produced by bacterium Gluconacetobacter xylinus were studied. Cellulose pellicles were produced by two strains (ATCC 53524 and ATCC 23769) for 1 and 7 days; pellicles were analyzed with scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrational sum-frequency-generation (SFG) spectroscopy, and attenuated total reflectance infrared (ATR-IR) spectroscopy. The bacterial cell population was higher at the surface exposed to air, indicating that the newly synthesized cellulose is deposited at the top of the pellicle. XRD, ATR-IR, and SFG analyses found no significant changes in the cellulose crystallinity, crystal size or polymorphic distribution with the culture time. However, SEM and SFG analyses revealed cellulose macrofibrils produced for 7 days had a higher packing density at the top of the pellicle, compared to the bottom. These findings suggest that the physical properties of cellulose microfibrils are different locally within the bacterial pellicles. PMID:26344281

  10. Agronomic effectiveness of biofertilizers with phosphate rock, sulphur and Acidithiobacillus for yam bean grown on a Brazilian tableland acidic soil.

    PubMed

    Stamford, N P; Santos, P R; Santos, C E S; Freitas, A D S; Dias, S H L; Lira, M A

    2007-04-01

    Phosphate rocks have low available P and soluble P fertilizers have been preferably used in plant crop production, although economic and effective P sources are needed. Experiments were carried out on a Brazilian Typic Fragiudult soil with low available P to evaluate the agronomic effectiveness of phosphate rock (PR) compared with soluble phosphate fertilizer. Yam bean (Pachyrhizus erosus) inoculated with rhizobia (strains NFB 747 and NFB 748) or not inoculated was the test crop. Biofertilizers were produced in field furrows by mixing phosphate rock (PR) and sulphur inoculated with Acidithiobacillus (S+Ac) in different rates (50, 100, 150 and 200 g S kg(-1) PR), with 60 days of incubation. Treatments were carried out with PR; biofertilizers B(50), B(100), B(150), B(200); triple super phosphate (TSP); B(200) without Acidithiobacillus and a control treatment without P application (P(0)). TSP and biofertilizers plus S inoculated with Acidithiobacillus increased plant growth. Soil acidity and available P increased when biofertilizers B(150) and B(200) were applied. We conclude that biofertilizers may be used as P source; however, long term use will reduce soil pH and potentially reduce crop growth. PMID:16815009

  11. The mechanism of bacterial action in the leaching of pyrite by Thiobacillus ferrooxidans. An electrochemical study

    SciTech Connect

    Holmes, P.R.; Fowler, T.A.; Crundwell, F.K.

    1999-08-01

    In many of the experiments reported in the literature on the leaching of pyrite by Thiobacillus ferrooxidans, the concentrations of ferric and ferrous ions in the presence of bacteria differ significantly from experiments conducted in their absence. In addition, these concentrations change throughout the course of the experiment. This makes it difficult to determine whether the presence of bacteria increases the rate of leaching above that for chemical leaching at the same solution conditions. The authors have designed an experimental apparatus to overcome this problem. This apparatus controls the redox potential in one compartment of an electrolytic cell by manipulating the current to the cell. In this manner, the concentrations of ferrous and ferric ions are maintained at their initial values for the duration of the experiment. Two types of experiments are reported in this paper. In the first, pyrite electrodes were exposed to solutions of the same bulk conditions in the presence and absence of bacteria, and their mixed potentials were determined. In the second, particulate pyrite was leached with and without bacteria to determine the effect that bacteria have on the rate of leaching. The mixed potential of bacterially dissolved pyrite decreases as microcolonies and biofilms form on the surface of pyrite electrode over a 14 day period. On the other hand, the mixed potential of chemically dissolved pyrite is constant over the same period. The results of the leaching experiments show that Thiobacillus ferrooxidans enhances the rate of leaching above that found in the absence of bacteria at the same conditions in solution. An electrochemical model of pyrite dissolution is derived that describes the mixed potential and the kinetics of pyrite leaching. This analysis indicates that the decrease in mixed potential and the increase in the leaching rate in the presence of bacteria are due to an increase in the pH at the surface.

  12. Existence of a new type of sulfite oxidase which utilizes ferric ions as an electron acceptor in Thiobacillus ferrooxidans

    SciTech Connect

    Sugio, T.; Katagiri, T.; Moriyama, M.; Zhen, Y.L.; Inagaki, K.; Tano, T.

    1988-01-01

    A new type of sulfite oxidase which utilizes ferric ion (Fe/sup 3 +/) as an electron acceptor was found in iron-grown Thiobacillus ferrooxidans. It was localized in the plasma membrane of the bacterium and had a pH optimum at 6.0. Under aerobic conditions, 1 mol of sulfite was oxidized by the enzyme to produce 1 mol of sulfate. Under anaerobic conditions in the presence of Fe/sup 3 +/, sulfite was oxidized by the enzyme as rapidly as it was under aerobic conditions. In the presence of o-phenanthroline or a chelator for Fe/sup 2 +/, the production of Fe/sup 2 +/ was observed during sulfite oxidation by this enzyme under not only anaerobic conditions but also aerobic conditions. No Fe/sup 2 +/ production was observed in the absence of o-phenanthroline, suggesting that the Fe/sup 2 +/ produced was rapidly reoxidized by molecular oxygen. Neither cytochrome c nor ferricyanide, both of which are electron acceptors for other sulfite oxidases, served as an electron acceptor for the sulfite oxidase of T. ferrooxidans. The enzyme was strongly inhibited by chelating agents for Fe/sup 3 +/. The physiological role of sulfite oxidase in sulfur oxidation of T. ferrooxidans is discussed.

  13. Evidence of biogenic corrosion of titanium after exposure to a continuous culture of thiobacillus ferrooxidans grown in thiosulfate medium

    SciTech Connect

    Horn, J M; Martin, S I; Masterson, B

    2000-12-07

    Experiments were undertaken to evaluate extreme conditions under which candidate materials intended for use in a proposed nuclear waste repository might be susceptible to corrosion by endogenous microorganisms. Thiobucillus ferrooxidans, a sulfur-oxidizing bacterium, was grown in continuous culture using thiosulfate as an energy source; thiosulfate is oxidized to sulfate as a metabolic endproduct by this organism. Culture conditions were optimized to produce a high-density, metabolically active culture throughout a period of long term incubation in the presence of Alloy 22 (a high nickel-based alloy) and Titanium grade 7 (Tigr7) material coupons. After seven months incubation under these conditions, material coupons were withdrawn and analyzed by high resolution microscopy and energy dispersive x-ray analyses. Alloy 22 coupons showed no detectable signs of corrosion. Tigr7, however, demonstrated distinct roughening of the coupon surface, and [presumably solubilized and precipitated] titanium was detected on Alloy 22 coupons incubated in the same T. ferrooxiduns culture vessel. Control coupons of these materials incubated in sterile thiosulfate medium did not demonstrate any signs of corrosion, thus showing that observed corrosive effects were due to the T. ferrooxidans metabolic activities. T. ferrooxidans intermediates of thiosulfate oxidation or sulfate may have caused the corrosive effects observed on Tigr7.

  14. Draft genome sequence of Rhodococcus rhodochrous strain ATCC 17895

    PubMed Central

    Chen, Bi-Shuang; Otten, Linda G.; Resch, Verena; Muyzer, Gerard; Hanefeld, Ulf

    2013-01-01

    Rhodococcus rhodochrous ATCC 17895 possesses an array of mono- and dioxygenases, as well as hydratases, which makes it an interesting organism for biocatalysis. R. rhodochrous is a Gram-positive aerobic bacterium with a rod-like morphology. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 6,869,887 bp long genome contains 6,609 protein-coding genes and 53 RNA genes. Based on small subunit rRNA analysis, the strain is more likely to be a strain of Rhodococcus erythropolis rather than Rhodococcus rhodochrous. PMID:24501654

  15. Thermostable purified endoglucanas from acidothermus cellulolyticus ATCC 43068

    DOEpatents

    Himmel, Michael E.; Adney, William S.; Tucker, Melvin P.; Grohmann, Karel

    1994-01-01

    A purified low molecular weight cellulase endoglucanase I having a molecular weight of between about 57,420 to about 74,580 daltons from Acidothermus cellulolyticus (ATCC 43068). The cellulase is water soluble, possesses both C.sub.1 and C.sub.x types of enzyme activity, a high degree of stability toward heat, and exhibits optimum temperature activity at about 83.degree. C. at pH's from about 2 to about 9, and in inactivation temperature of about 110.degree. C. at pH's from about 2 to about 9.

  16. Thermostable purified endoglucanase from Acidothermus cellulolyticus ATCC 43068

    DOEpatents

    Himmel, M.E.; Adney, W.S.; Tucker, M.P.; Grohmann, K.

    1994-01-04

    A purified low molecular weight cellulase endoglucanase I having a molecular weight of between about 57,420 to about 74,580 daltons from Acidothermus cellulolyticus (ATCC 43068) is presented. The cellulase is water soluble, possesses both C[sub 1] and C[sub x] types of enzyme activity, a high degree of stability toward heat, and exhibits optimum temperature activity at about 83 C at pH's from about 2 to about 9, and in inactivation temperature of about 110 C at pH's from about 2 to about 9. 7 figures.

  17. Method of producing a cellulase-containing cell-free fermentate produced from microorganism ATCC 55702

    DOEpatents

    Dees, H. Craig

    1998-01-01

    Bacteria which produce large amounts of cellulose-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

  18. Method of producing a cellulase-containing cell-free fermentate produced from microorganism ATCC 55702

    DOEpatents

    Dees, H.C.

    1998-05-26

    Bacteria which produce large amounts of cellulose-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques. 5 figs.

  19. Cellulase-containing cell-free fermentate produced from microorganism ATCC 55702

    DOEpatents

    Dees, H. Craig

    1997-12-16

    Bacteria which produce large amounts of cellulase-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

  20. Cellulase-containing cell-free fermentate produced from microorganism ATCC 55702

    DOEpatents

    Dees, H.C.

    1997-12-16

    Bacteria which produce large amounts of cellulase-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques. 5 figs.

  1. Production of Biohydrogen from Wastewater by Klebsiella oxytoca ATCC 13182.

    PubMed

    Thakur, Veena; Tiwari, K L; Jadhav, S K

    2015-08-01

    Production of biohydrogen from distillery effluent was carried out by using Klebsiella oxytoca ATCC 13182. The work focuses on optimization of pH, temperature, and state of bacteria, which are the various affecting factors for fermentative biohydrogen production. Results indicates that at 35 °C for suspended cultures, the production was at its maximum (i.e., 91.33 ± 0.88 mL) when compared with other temperatures. At 35 °C and at pH 5 and 6, maximum productions of 117.67 ± 1.45 and 111.67 ± 2.72 mL were observed with no significant difference. When immobilized, Klebsiella oxytoca ATCC 13182 was used for biohydrogen production at optimized conditions, production was 186.33 ± 3.17 mL. Hence, immobilized cells were found to be more advantageous for biological hydrogen production over suspended form. Physicochemical analysis of the effluent was conducted before and after fermentation and the values suggested that the fermentative process is an efficient method for biological treatment of wastewater. PMID:26237683

  2. Induction of natural competence in Bacillus cereus ATCC14579

    PubMed Central

    Mirończuk, Aleksandra M.; Kovács, Ákos T.; Kuipers, Oscar P.

    2008-01-01

    Summary Natural competence is the ability of certain microbes to take up exogenous DNA from the environment and integrate it in their genome. Competence development has been described for a variety of bacteria, but has so far not been shown to occur in Bacillus cereus. However, orthologues of most proteins involved in natural DNA uptake in Bacillus subtiliscould be identified in B. cereus. Here, we report that B. cereus ATCC14579 can become naturally competent. When expressing the B. subtilis ComK protein using an IPTG‐inducible system in B. cereus ATCC14579, cells grown in minimal medium displayed natural competence, as either genomic DNA or plasmid DNA was shown to be taken up by the cells and integrated into the genome or stably maintained respectively. This work proves that a sufficient structural system for DNA uptake exists in B. cereus. Bacillus cereus can be employed as a model system to investigate the mechanism of DNA uptake in related bacteria such as Bacillus anthracis and Bacillus thuringiensis. Moreover, natural competence provides an important tool for biotechnology, as it will allow more efficient transformation of B. cereus and related organisms, e.g. to knockout genes in a high‐throughput way. PMID:21261842

  3. Bioleaching of nickel from spent petroleum catalyst using Acidithiobacillus thiooxidans DSM- 11478.

    PubMed

    Sharma, Mohita; Bisht, Varsha; Singh, Bina; Jain, Pratiksha; Mandal, Ajoy K; Lal, Banwari; Sarma, Priyangshu M

    2015-06-01

    The present work deals with optimization of culture conditions and process parameters for bioleaching of spent petroleum catalyst collected from a petroleum refinery. The efficacy of Ni bioleaching from spent petroleum catalyst was determined using pure culture of Acidithiobacillus thiooxidans DSM- 11478. The culture conditions of pH, temperature and headspace volume to media volume ratio were optimized. EDX analysis was done to confirm the presence of Ni in the spent catalyst after roasting it to decoke its surface. The optimum temperature for A. thiooxidans DSM-11478 growth was found to be 32 degrees C. The enhanced recovery of nickel at very low pH was attributed to the higher acidic strength of sulfuric acid produced in the culture medium by the bacterium. During the bioleaching process, 89% of the Ni present in the catalyst waste could be successfully recovered in optimized conditions. This environment friendly bioleaching process proved efficient than the chemical method. Taking leads from the lab scale results, bioleaching in larger volumes (1, 5 and 10 L) was also performed to provide guidelines for taking up this technology for in situ industrial waste management. PMID:26155679

  4. Biosorption and biodegradation of a sulfur dye in high-strength dyeing wastewater by Acidithiobacillus thiooxidans.

    PubMed

    Nguyen, Thai Anh; Fu, Chun-Chieh; Juang, Ruey-Shin

    2016-11-01

    The ability of the bacterial strain Acidithiobacillus thiooxidans to remove sulfur blue 15 (SB15) dye from water samples was examined. This bacterium could not only oxidize sulfur compounds to sulfuric acid but also promote the attachment of the cells to the surface of sulfidic particles, therefore serving as an efficient biosorbent. The biosorption isotherms were better described by the Langmuir equation than by the Freundlich or Dubinin-Radushkevich equation. Also, the biosorption process followed the pseudo-second-order kinetics. At pH 8.3 and SB15 concentrations up to 2000 mg L(-1) in the biomass/mineral salt solution, the dye removal and decolorization were 87.5% and 91.4%, respectively, following the biosorption process. Biodegradation was proposed as a subsequent process for the remaining dye (250-350 mg L(-1)). A central composite design was used to analyze independent variables in the response surface methodology study. Under the optimal conditions (i.e., initial dye concentration of 300 mg L(-1), initial biomass concentration of 1.0 g L(-1), initial pH of 11.7, and yeast extract dose of 60 mg L(-1)), up to 50% of SB15 was removed after 4 days of biodegradation. PMID:27486930

  5. Inhibition of microbial concrete corrosion by Acidithiobacillus thiooxidans with functionalised zeolite-A coating.

    PubMed

    Haile, Tesfaalem; Nakhla, George

    2009-01-01

    The inhibition of the corrosive action of Acidithiobacillus thiooxidans on concrete specimens coated by functionalised zeolite-A containing 14% zinc and 5% silver by weight was studied. Uncoated concrete specimens, epoxy-coated concrete specimens (EP), and functionalised zeolite-A coated concrete specimens with epoxy to zeolite weight ratios of 3:1 (Z1), 2:2 (Z2) and 1:3 (Z3) were studied. Specimens were characterised by x-ray powder diffraction and field emission scanning electron microscopy for the identification of corrosion products and morphological changes. Biomass growth at the conclusion of the 32-day experiments was 4, 179 and 193 mg volatile suspended solids g(-1) sulphur for the uncoated, EP and Z1 specimens, whereas that of Z2 and Z3 were negligible. In the uncoated, EP and Z1 specimens, sulphate production rates were 0.83, 9.1 and 8.8 mM SO(4)(2-) day(-1) and the specific growth rates, mu, were 0.14, 0.57 and 0.47 day(-1), respectively. The corresponding values for Z2 and Z3 were negligible due to their bacterial inhibition characteristics. PMID:18846450

  6. Oxidation of elemental sulfur, tetrathionate and ferrous iron by the psychrotolerant Acidithiobacillus strain SS3.

    PubMed

    Kupka, Daniel; Liljeqvist, Maria; Nurmi, Pauliina; Puhakka, Jaakko A; Tuovinen, Olli H; Dopson, Mark

    2009-12-01

    Mesophilic iron and sulfur-oxidizing acidophiles are readily found in acid mine drainage sites and bioleaching operations, but relatively little is known about their activities at suboptimal temperatures and in cold environments. The purpose of this work was to characterize the oxidation of elemental sulfur (S(0)), tetrathionate (S4O6(2-)) and ferrous iron (Fe2+) by the psychrotolerant Acidithiobacillus strain SS3. The rates of elemental sulfur and tetrathionate oxidation had temperature optima of 20 degrees and 25 degrees C, respectively, determined using a temperature gradient incubator that involved narrow (1.1 degrees C) incremental increases from 5 degrees to 30 degrees C. Activation energies calculated from the Arrhenius plots were 61 and 89 kJ mol(-1) for tetrathionate and 110 kJ mol(-1) for S(0) oxidation. The oxidation of elemental sulfur produced sulfuric acid at 5 degrees C and decreased the pH to approximately 1. The low pH inhibited further oxidation of the substrate. In media with both S(0) and Fe2+, oxidation of elemental sulfur did not commence until all available ferrous iron was oxidized. These data on sequential oxidation of the two substrates are in keeping with upregulation and downregulation of several proteins previously noted in the literature. Ferric iron was reduced to Fe2+ in parallel with elemental sulfur oxidation, indicating the presence of a sulfur:ferric iron reductase system in this bacterium. PMID:19782750

  7. Toxicity of select organic acids to the slightly thermophilic acidophile Acidithiobacillus caldus.

    PubMed

    Aston, John E; Apel, William A; Lee, Brady D; Peyton, Brent M

    2009-02-01

    Acidithiobacillus caldus is a thermophilic acidophile found in commercial biomining, acid mine drainage systems, and natural environments. Previous work has characterized A. caldus as a chemolithotrophic autotroph capable of utilizing reduced sulfur compounds under aerobic conditions. Organic acids are especially toxic to chemolithotrophs in low-pH environments, where they diffuse more readily into the cell and deprotonate within the cytoplasm. In the present study, the toxic effects of oxaloacetate, pyruvate, 2-ketoglutarate, acetate, malate, succinate, and fumarate on A. caldus strain BC13 were examined under batch conditions. All tested organic acids exhibited some inhibitory effect. Oxaloacetate was observed to inhibit growth completely at a concentration of 250 microM, whereas other organic acids were completely inhibitory at concentrations of between 1,000 and 5,000 microM. In these experiments, the measured concentrations of organic acids decreased with time, indicating uptake or assimilation by the cells. Phospholipid fatty acid analyses indicated an effect of organic acids on the cellular envelope. Notable differences included an increase in cyclic fatty acids in the presence of organic acids, indicating possible instability of the cellular envelope. This was supported by field emission scanning-electron micrographs showing blebbing and sluffing in cells grown in the presence of organic acids. PMID:18803441

  8. Regulation of a novel Acidithiobacillus caldus gene cluster involved in metabolism of reduced inorganic sulfur compounds.

    PubMed

    Rzhepishevska, Olena I; Valdés, Jorge; Marcinkeviciene, Liucija; Gallardo, Camelia Algora; Meskys, Rolandas; Bonnefoy, Violaine; Holmes, David S; Dopson, Mark

    2007-11-01

    Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation. PMID:17873067

  9. Influence of the sulfur species reactivity on biofilm conformation during pyrite colonization by Acidithiobacillus thiooxidans.

    PubMed

    Lara, René H; García-Meza, J Viridiana; Cruz, Roel; Valdez-Pérez, Donato; González, Ignacio

    2012-08-01

    Massive pyrite (FeS₂) electrodes were potentiostatically modified by means of variable oxidation pulse to induce formation of diverse surface sulfur species (S(n)²⁻, S⁰). The evolution of reactivity of the resulting surfaces considers transition from passive (e.g., Fe(1-x )S₂) to active sulfur species (e.g., Fe(1-x )S(2-y ), S⁰). Selected modified pyrite surfaces were incubated with cells of sulfur-oxidizing Acidithiobacillus thiooxidans for 24 h in a specific culture medium (pH 2). Abiotic control experiments were also performed to compare chemical and biological oxidation. After incubation, the attached cells density and their exopolysaccharides were analyzed by confocal laser scanning microscopy (CLMS) and atomic force microscopy (AFM) on bio-oxidized surfaces; additionally, S(n)²⁻/S⁰ speciation was carried out on bio-oxidized and abiotic pyrite surfaces using Raman spectroscopy. Our results indicate an important correlation between the evolution of S(n)²⁻/S⁰ surface species ratio and biofilm formation. Hence, pyrite surfaces with mainly passive-sulfur species were less colonized by A. thiooxidans as compared to surfaces with active sulfur species. These results provide knowledge that may contribute to establishing interfacial conditions that enhance or delay metal sulfide (MS) dissolution, as a function of the biofilm formed by sulfur-oxidizing bacteria. PMID:22113561

  10. Regulation of a Novel Acidithiobacillus caldus Gene Cluster Involved in Metabolism of Reduced Inorganic Sulfur Compounds▿

    PubMed Central

    Rzhepishevska, Olena I.; Valdés, Jorge; Marcinkeviciene, Liucija; Gallardo, Camelia Algora; Meskys, Rolandas; Bonnefoy, Violaine; Holmes, David S.; Dopson, Mark

    2007-01-01

    Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation. PMID:17873067

  11. Antibacterial Activity of Synthetic Peptides Derived from Lactoferricin against Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212

    PubMed Central

    León-Calvijo, María A.; Leal-Castro, Aura L.; Almanzar-Reina, Giovanni A.; Rosas-Pérez, Jaiver E.; García-Castañeda, Javier E.; Rivera-Monroy, Zuly J.

    2015-01-01

    Peptides derived from human and bovine lactoferricin were designed, synthesized, purified, and characterized using RP-HPLC and MALDI-TOF-MS. Specific changes in the sequences were designed as (i) the incorporation of unnatural amino acids in the sequence, the (ii) reduction or (iii) elongation of the peptide chain length, and (iv) synthesis of molecules with different number of branches containing the same sequence. For each peptide, the antibacterial activity against Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212 was evaluated. Our results showed that Peptides I.2 (RWQWRWQWR) and I.4 ((RRWQWR)4K2Ahx2C2) exhibit bigger or similar activity against E. coli (MIC 4–33 μM) and E. faecalis (MIC 10–33 μM) when they were compared with lactoferricin protein (LF) and some of its derivate peptides as II.1 (FKCRRWQWRMKKLGA) and IV.1 (FKCRRWQWRMKKLGAPSITCVRRAE). It should be pointed out that Peptides I.2 and I.4, containing the RWQWR motif, are short and easy to synthesize; our results demonstrate that it is possible to design and obtain synthetic peptides that exhibit enhanced antibacterial activity using a methodology that is fast and low-cost and that allows obtaining products with a high degree of purity and high yield. PMID:25815317

  12. Antibacterial activity of synthetic peptides derived from lactoferricin against Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212.

    PubMed

    León-Calvijo, María A; Leal-Castro, Aura L; Almanzar-Reina, Giovanni A; Rosas-Pérez, Jaiver E; García-Castañeda, Javier E; Rivera-Monroy, Zuly J

    2015-01-01

    Peptides derived from human and bovine lactoferricin were designed, synthesized, purified, and characterized using RP-HPLC and MALDI-TOF-MS. Specific changes in the sequences were designed as (i) the incorporation of unnatural amino acids in the sequence, the (ii) reduction or (iii) elongation of the peptide chain length, and (iv) synthesis of molecules with different number of branches containing the same sequence. For each peptide, the antibacterial activity against Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212 was evaluated. Our results showed that Peptides I.2 (RWQWRWQWR) and I.4 ((RRWQWR)4K2Ahx2C2) exhibit bigger or similar activity against E. coli (MIC 4-33 μM) and E. faecalis (MIC 10-33 μM) when they were compared with lactoferricin protein (LF) and some of its derivate peptides as II.1 (FKCRRWQWRMKKLGA) and IV.1 (FKCRRWQWRMKKLGAPSITCVRRAE). It should be pointed out that Peptides I.2 and I.4, containing the RWQWR motif, are short and easy to synthesize; our results demonstrate that it is possible to design and obtain synthetic peptides that exhibit enhanced antibacterial activity using a methodology that is fast and low-cost and that allows obtaining products with a high degree of purity and high yield. PMID:25815317

  13. Complete Genome and Methylome Sequences of Salmonella enterica subsp. enterica Serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica Serovar Sloterdijk (ATCC 15791).

    PubMed

    Yao, Kuan; Muruvanda, Tim; Roberts, Richard J; Payne, Justin; Allard, Marc W; Hoffmann, Maria

    2016-01-01

    Salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. Salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. In this report, we announce the first complete genome and methylome sequences from two Salmonella type strains associated with food-borne outbreaks, Salmonella enterica subsp. enterica serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica serovar Sloterdijk (ATCC 15791). PMID:26988049

  14. Pseudomonas oleovorans subsp. lubricantis subsp. nov., and reclassification of Pseudomonas pseudoalcaligenes ATCC 17440T as later synonym of Pseudomonas oleovorans ATCC 8062 T.

    PubMed

    Saha, Ratul; Spröer, Cathrin; Beck, Brian; Bagley, Susan

    2010-04-01

    Isolate RS1(T) isolated from used metalworking fluid was found to be a Gram-negative, motile, and non-spore forming rod. Based on phylogenetic analyses with 16S rRNA, isolate RS1(T) was placed into the mendocina sublineage of Pseudomonas. The major whole cell fatty acids were C(18:1)omega7c (32.6%), C(16:0) (25.5%), and C(15:0) ISO 2OH/C(16:1)omega7c (14.4%). The sequence similarities of isolate RS1(T) based on gyrB and rpoD genes were 98.9 and 98.0% with Pseudomonas pseudoalcaligenes, and 98.5 and 98.1% with Pseudomonas oleovorans, respectively. The ribotyping pattern showed a 0.60 similarity with P. oleovorans ATCC 8062(T) and 0.63 with P. pseudoalcaligenes ATCC17440(T). The DNA G + C content of isolate RS1(T) was 62.2 mol.%. The DNA-DNA relatedness was 73.0% with P. oleovorans ATCC 8062(T) and 79.1% with P. pseudoalcaligenes ATCC 17440(T). On the basis of morphological, biochemical, and molecular studies, isolate RS1(T) is considered to represent a new subspecies of P. oleovorans. Furthermore, based on the DNA-DNA relatedness (>70%), chemotaxonomic, and molecular profile, P. pseudoalcaligenes ATCC 17440(T) and P. oleovorans ATCC 8062(T) should be united under the same name; according to the rules of priority, P. oleovorans, the first described species, is the earlier synonym and P. pseudoalcaligenes is the later synonym. As a consequence, the division of the species P. oleovorans into two novel subspecies is proposed: P. oleovorans subsp. oleovorans subsp. nov. (type strain ATCC 8062(T) = DSM 1045(T) = NCIB 6576(T)), P. oleovorans subsp. lubricantis subsp. nov. (type strain RS1(T) = ATCC BAA-1494(T) = DSM 21016(T)). PMID:19936829

  15. Complete Genome and Methylome Sequences of Salmonella enterica subsp. enterica Serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica Serovar Sloterdijk (ATCC 15791)

    PubMed Central

    Yao, Kuan; Muruvanda, Tim; Roberts, Richard J.; Payne, Justin; Allard, Marc W.

    2016-01-01

    Salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. Salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. In this report, we announce the first complete genome and methylome sequences from two Salmonella type strains associated with food-borne outbreaks, Salmonella enterica subsp. enterica serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica serovar Sloterdijk (ATCC 15791). PMID:26988049

  16. Complete Genome Sequence of Arthrobacter sp. ATCC 21022, a Host for Bacteriophage Discovery

    PubMed Central

    Russell, Daniel A.

    2016-01-01

    We report the complete genome sequence of Arthrobacter sp. ATCC 21022, a strain maintained by ATCC and a commonly used host for bacteriophage isolation and genomic analysis. The strain is prophage-free and CRISPR-free but codes for two predicted restriction-modification systems. PMID:27013048

  17. Growth of Lactobacillus paracasei ATCC334 in a cheese model system: A biochemical approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growth of Lactobacillus paracasei ATCC 334, in a cheese-ripening model system based upon a medium prepared from ripening Cheddar cheese extract (CCE) was evaluated. Lactobacillus paracasei ATCC 334 grows in CCE made from cheese ripened for 2 (2mCCE), 6 (6mCCE), and 8 (8mCCE) mo, to final cell densit...

  18. Identification of the Herboxidiene Biosynthetic Gene Cluster in Streptomyces chromofuscus ATCC 49982

    PubMed Central

    Shao, Lei; Zi, Jiachen; Zeng, Jia

    2012-01-01

    The 53-kb biosynthetic gene cluster for the novel anticholesterol natural product herboxidiene was identified in Streptomyces chromofuscus ATCC 49982 by genome sequencing and gene inactivation. In addition to herboxidiene, a biosynthetic intermediate, 18-deoxy-herboxidiene, was also isolated from the fermentation broth of S. chromofuscus ATCC 49982 as a minor metabolite. PMID:22247174

  19. Draft Genome Sequence of Chemolithoautotrophic Acetogenic Butanol-Producing Eubacterium limosum ATCC 8486

    PubMed Central

    Song, Yoseb

    2015-01-01

    Eubacterium limosum ATCC 8486 is an anaerobic chemolithoautotrophic acetogenic bacterium that converts and transforms syngas and isoflavonoids to butanol and phytoestrogens, respectively. Here, we report the draft genome sequence of the E. limosum ATCC 8486 (4.37 Mb) strain and its annotation information, including syngas fermentation and denitrification metabolic pathways. PMID:25676768

  20. Complete Genome Sequence of Klebsiella quasipneumoniae subsp. similipneumoniae Strain ATCC 700603

    PubMed Central

    Elliott, Alysha G.; Ganesamoorthy, Devika; Coin, Lachlan; Cooper, Matthew A.

    2016-01-01

    Klebsiella quasipneumoniae subsp. similipneumoniae strain ATCC 700603, formerly known as K. pneumoniae K6, is known for producing extended-spectrum β-lactamase (ESBL) enzymes that can hydrolyze oxyimino-β-lactams, resulting in resistance to these drugs. We herein report the complete genome of strain ATCC 700603 and show that the ESBL genes are plasmid-encoded. PMID:27231369

  1. Osmoresistant yeast Zygosaccharomyces rouxii: the two most studied wild-type strains (ATCC 2623 and ATCC 42981) differ in osmotolerance and glycerol metabolism.

    PubMed

    Pribylova, Lenka; de Montigny, Jacky; Sychrova, Hana

    2007-03-01

    The yeast Zygosaccharomyces rouxii is known for its high tolerance to osmotic stress, which is thought to be caused by sets of specific genes. Relatively few Z. rouxii genes have been identified so far, all of them having homologues in Saccharomyces cerevisiae; none of them was Z. rouxii-specific. Most of the known Z. rouxii genes were isolated from two wild-type strains, ATCC 2623 and ATCC 42981. In this study, we compared these two strains with regard to some of their morphological, physiological and genomic properties. Important differences were found in their salt tolerance and assimilation of glycerol and karyotype; slight differences were also present in their cell morphology. The ATCC 42981 strain showed a higher resistance to salts, higher glycerol production and, unlike ATCC 2623, was able to assimilate glycerol. Under conditions of osmotic stress, the glycerol production in both Z. rouxii strains was much lower than in a S. cerevisiae S288c culture, which suggested the presence of a system that efficiently retains glycerol inside Z. rouxii cells. The karyotype analysis revealed that ATCC 42981 cells contain more chromosomes and have a bigger genome size than those of ATCC 2623. PMID:17351908

  2. Functional Characterization of the FoxE Iron Oxidoreductase from the Photoferrotroph Rhodobacter ferrooxidans SW2*

    PubMed Central

    Saraiva, Ivo H.; Newman, Dianne K.; Louro, Ricardo O.

    2012-01-01

    Photoferrotrophy is presumed to be an ancient type of photosynthetic metabolism in which bacteria use the reducing power of ferrous iron to drive carbon fixation. In this work the putative iron oxidoreductase of the photoferrotroph Rhodobacter ferrooxidans SW2 was cloned, purified, and characterized for the first time. This protein, FoxE, was characterized using spectroscopic, thermodynamic, and kinetic techniques. It is a c-type cytochrome that forms a trimer or tetramer in solution; the two hemes of each monomer are hexacoordinated by histidine and methionine. The hemes have positive reduction potentials that allow downhill electron transfer from many geochemically relevant ferrous iron forms to the photosynthetic reaction center. The reduction potentials of the hemes are different and are cross-assigned to fast and slow kinetic phases of ferrous iron oxidation in vitro. Lower reactivity was observed at high pH and may contribute to prevent ferric iron precipitation inside or at the surface of the cell. These results help fill in the molecular details of a metabolic process that likely contributed to the deposition of precambrian banded iron formations, globally important sedimentary rocks that are found on every continent today. PMID:22661703

  3. Functional characterization of the FoxE iron oxidoreductase from the photoferrotroph Rhodobacter ferrooxidans SW2.

    PubMed

    Saraiva, Ivo H; Newman, Dianne K; Louro, Ricardo O

    2012-07-20

    Photoferrotrophy is presumed to be an ancient type of photosynthetic metabolism in which bacteria use the reducing power of ferrous iron to drive carbon fixation. In this work the putative iron oxidoreductase of the photoferrotroph Rhodobacter ferrooxidans SW2 was cloned, purified, and characterized for the first time. This protein, FoxE, was characterized using spectroscopic, thermodynamic, and kinetic techniques. It is a c-type cytochrome that forms a trimer or tetramer in solution; the two hemes of each monomer are hexacoordinated by histidine and methionine. The hemes have positive reduction potentials that allow downhill electron transfer from many geochemically relevant ferrous iron forms to the photosynthetic reaction center. The reduction potentials of the hemes are different and are cross-assigned to fast and slow kinetic phases of ferrous iron oxidation in vitro. Lower reactivity was observed at high pH and may contribute to prevent ferric iron precipitation inside or at the surface of the cell. These results help fill in the molecular details of a metabolic process that likely contributed to the deposition of precambrian banded iron formations, globally important sedimentary rocks that are found on every continent today. PMID:22661703

  4. Iron Oxidation and Precipitation of Ferric Hydroxysulfates by Resting Thiobacillus ferrooxidans Cells

    PubMed Central

    Lazaroff, Norman; Sigal, Warren; Wasserman, Andrew

    1982-01-01

    The oxidation of ferrous ions, in acid solution, by resting suspensions of Thiobacillus ferrooxidans produced sediments consisting of crystalline jarosites, amorphous ferric hydroxysulfates, or both. These products differed conspicuously in chemical composition and infrared spectra from precipitates formed by abiotic oxidation under similar conditions. The amorphous sediments, produced by bacterial oxidation, exhibited a distinctive fibroporous microstructure when examined by scanning electron microscopy. Infrared spectra indicated outer-sphere coordination of Fe(III) by sulfate ions, as well as inner-sphere coordination by water molecules and bridging hydroxo groups. In the presence of excess sulfate and appropriate monovalent cations, jarosites, instead of amorphous ferric hydroxysulfates, precipitated from bacterially oxidized iron solutions. It is proposed that the jarositic precipitates result from the conversion of outer-sphere (Td) sulfate, present in a soluble polymeric Fe(III) complex, to inner-sphere (C3v) bridging sulfate. The amorphous precipitates result from the further polymerization of hydroxo-linked iron octahedra and charge stabilized aggregation of the resulting iron complexes in solution. This view was supported by observations that bacterially oxidized iron solutions gave rise to either amorphous or jarositic sediments in response to ionic environments imposed after oxidation had been completed and the bacteria had been removed by filtration. Images PMID:16345996

  5. Complete genome sequence of Anabaena variabilis ATCC 29413

    SciTech Connect

    Thiel, Teresa; Pratte, Brenda S.; Zhong, Jinshun; Goodwin, Lynne A.; Copeland, A; Lucas, Susan; Han, Cliff; Pitluck, Sam; Land, Miriam L; Kyrpides, Nikos C; Woyke, Tanja

    2013-01-01

    Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbon and energy source. While this strain was first isolated in 1964 in Mississippi and named Ana-baena flos-aquae MSU A-37, it clusters phylogenetically with cyanobacteria of the genus Nostoc. The strain is a moderate thermophile, growing well at approximately 40 C. Here we provide some additional characteristics of the strain, and an analysis of the complete genome sequence.

  6. Xanthomonas campestris atcc 31601 and process for use

    SciTech Connect

    Weisrock, W.P.; McCarthy, E.F.

    1983-11-29

    A degenerative-resistant strain of Xanthomonas campestris has been developed and a process for using this strain to effectively overcome the problems of continuous xanthan production. This strain of X. campestris, designated X. campestris XCP-19 ATCC 31601, is capable of continuously producing xanthan at high specific productivities, i.e., 0.24 to 0.32 gm xanthan/gm cells/hr, for several hundred hours without culture degeneration from inexpensive aqueous nutrient media such as, for example, a minimal medium consisting primarily of inorganic salts, glucose, and NH4Cl. The medium may or may not also contain a yeast extract or yeast autolysate as a supplemental nitrogen source. Any medium having assimilable sources of carbon, nitrogen, and inorganic substances will serve satisfactorily for use with this new organism. 14 claims.

  7. Complete genome sequence of Anabaena variabilis ATCC 29413.

    PubMed

    Thiel, Teresa; Pratte, Brenda S; Zhong, Jinshun; Goodwin, Lynne; Copeland, Alex; Lucas, Susan; Han, Cliff; Pitluck, Sam; Land, Miriam L; Kyrpides, Nikos C; Woyke, Tanja

    2014-06-15

    Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbon and energy source. While this strain was first isolated in 1964 in Mississippi and named Anabaena flos-aquae MSU A-37, it clusters phylogenetically with cyanobacteria of the genus Nostoc. The strain is a moderate thermophile, growing well at approximately 40(°) C. Here we provide some additional characteristics of the strain, and an analysis of the complete genome sequence. PMID:25197444

  8. Thermostable Cyanuric Acid Hydrolase from Moorella thermoacetica ATCC 39073▿

    PubMed Central

    Li, Qingyan; Seffernick, Jennifer L.; Sadowsky, Michael J.; Wackett, Lawrence P.

    2009-01-01

    Cyanuric acid, a metabolic intermediate in the degradation of many s-triazine compounds, is further metabolized by cyanuric acid hydrolase. Cyanuric acid also accumulates in swimming pools due to the breakdown of the sanitizing agents di- and trichloroisocyanuric acid. Structurally stable cyanuric acid hydrolases are being considered for usage in pool water remediation. In this study, cyanuric acid hydrolase from the thermophile Moorella thermoacetica ATCC 39073 was cloned, expressed in Escherichia coli, and purified to homogeneity. The recombinant enzyme was found to have a broader temperature range and greater stability, at both elevated and low temperatures, than previously described cyanuric acid hydrolases. The enzyme had a narrow substrate specificity, acting only on cyanuric acid and N-methylisocyanuric acid. The M. thermoacetica enzyme did not require metals or other discernible cofactors for activity. Cyanuric acid hydrolase from M. thermoacetica is the most promising enzyme to use for cyanuric acid remediation applications. PMID:19767460

  9. Growth effects and assimilation of organic acids in Chemostat and Batch Cultures of Acidithiobacillus caldus

    SciTech Connect

    John E. Aston; William A. Apel; Brady D. Lee; Brent M. Peyton

    2011-01-01

    The ability of Acidithiobacillus caldus to grow aerobically using pyruvate, acetate, citrate, 2-ketoglutarate, succinate, and malate as either an electron donor and carbon source (heterotrophic growth), or as a carbon source when potassium tetrathionate was added as an electron donor (mixotrophic growth), was tested in chemostat cultures. Under both heterotrophic and mixotrophic conditions, organic acids were added to a sub-lethal concentration (50 M). Under mixotrophic conditions, potassium tetrathionate was added to an excess concentration (10 mM). No cell growth was observed under heterotrophic conditions; however effluent cell concentrations increased over three-fold when pyruvate was coupled with potassium tetrathionate. Under these conditions, the effluent pyruvate concentration was reduced to below the detection limit (2 M), and oxygen consumption increased by approximately 100%. Although pyruvate provided a carbon source in these experiments, ambient carbon dioxide was also available to the cells. To test whether At. caldus could grow mixotrophically using pyruvate as a sole carbon source and potassium tetrathionate as an electron donor, cells were batch cultured in a medium free of dissolved inorganic carbon, and with no carbon dioxide in the headspace. These experiments showed that At. caldus was able to convert pyruvate between 65 ± 8 and 82 ± 15% of the pyruvate carbon to cellular biomass, depending on the initial pyruvate concentrations. This work is the first to identify a defined organic-carbon source, other than glucose, that At. caldus can assimilate. This has important implications, as mixotrophic and heterotrophic activity has been shown to increase mineral leaching in acidic systems.

  10. Bioleaching of arsenic from highly contaminated mine tailings using Acidithiobacillus thiooxidans.

    PubMed

    Lee, Eunseong; Han, Yosep; Park, Jeonghyun; Hong, Jeongsik; Silva, Rene A; Kim, Seungkon; Kim, Hyunjung

    2015-01-01

    The behavior of arsenic (As) bioleaching from mine tailings containing high amount of As (ca. 34,000 mg/kg) was investigated using Acidithiobacillus thiooxidans to get an insight on the optimal conditions that would be applied to practical heap and/or tank bioleaching tests. Initial pH (1.8-2.2), temperature (25-40 °C), and solid concentration (0.5-4.0%) were employed as experimental parameters. Complementary characterization experiments (e.g., XRD, SEM-EDS, electrophoretic mobility, cell density, and sulfate production) were also carried out to better understand the mechanism of As bioleaching. The results showed that final As leaching efficiency was similar regardless of initial pH. However, greater initial As leaching rate was observed at initial pH 1.8 than other conditions, which could be attributed to greater initial cell attachment to mine tailings. Unlike the trend observed when varying the initial pH, the final As leaching efficiency varied with the changes in temperature and solid concentration. Specifically, As leaching efficiency tended to decrease with increasing temperature due to the decrease in the bacterial growth rate at higher temperature. Meanwhile, As leaching efficiency tended to increase with decreasing solid concentration. The results for jarosite contents in mine tailings residue after bioleaching revealed that much greater amount of the jarosite was formed during the bioleaching reaction at higher solid concentration, suggesting that the coverage of the surface of the mine tailings by jarosite and/or the co-precipitation of the leached As with jarosite could be a dominant factor reducing As leaching efficiency. PMID:25262394

  11. Construction of small plasmid vectors for use in genetic improvement of the extremely acidophilic Acidithiobacillus caldus.

    PubMed

    Meng, Jianzhou; Wang, Huiyan; Liu, Xiangmei; Lin, Jianqun; Pang, Xin; Lin, Jianqiang

    2013-10-01

    The genetic improvement of biomining bacteria including Acidithiobacillus caldus could facilitate the bioleaching process of sulfur-containing minerals. However, the available vectors for use in A. caldus are very scanty and limited to relatively large broad-host-range IncQ plasmids. In this study, a set of small, mobilizable plasmid vectors (pBBR1MCS-6, pMSD1 and pMSD2) were constructed based on plasmid pBBR1MCS-2, which does not belong to the IncQ, IncW, or IncP groups. The function of the tac promoter on 5.8-kb pMSD2 was determined by inserting a kanamycin-resistant reporter gene. The resulting recombinant pMSD2-Km was successfully transferred by conjugation into A. caldus MTH-04 with transfer frequency of 1.38±0.64×10(-5). The stability and plasmid copy number of pMSD2-Km in A. caldus MTH-04 were 75±2.7% and 5-6 copies per cell, respectively. By inserting an arsABC operon into pMSD2, an arsenic-resistant recombinant pMSD2-As was constructed and transferred into A. caldus MTH-04 by conjugation. The arsenic tolerance of A. caldus MTH-04 containing pMSD2-As was obviously increased up to 45mM of NaAsO2. These vectors could be applied in genetic improvement of A. caldus as well as other bioleaching bacteria. PMID:23639949

  12. Influence of the surface speciation on biofilm attachment to chalcopyrite by Acidithiobacillus thiooxidans.

    PubMed

    Lara, René H; García-Meza, J Viridiana; González, Ignacio; Cruz, Roel

    2013-03-01

    Surfaces of massive chalcopyrite (CuFeS2) electrodes were modified by applying variable oxidation potential pulses under growth media in order to induce the formation of different secondary phases (e.g., copper-rich polysulfides, S n(2-); elemental sulfur, S(0); and covellite, CuS). The evolution of reactivity (oxidation capacity) of the resulting chalcopyrite surfaces considers a transition from passive or inactive (containing CuS and S n(2-)) to active (containing increasing amounts of S(0)) phases. Modified surfaces were incubated with cells of sulfur-oxidizing bacteria (Acidithiobacillus thiooxidans) for 24 h in a specific culture medium (pH 2). Abiotic control experiments were also performed to compare chemical and biological oxidation. After incubation, the density of cells attached to chalcopyrite surfaces, the structure of the formed biofilm, and their exopolysaccharides and nucleic acids were analyzed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy coupled to dispersive X-ray analysis (SEM-EDS). Additionally, CuS and S n(2-)/S(0) speciation, as well as secondary phase evolution, was carried out on biooxidized and abiotic chalcopyrite surfaces using Raman spectroscopy and SEM-EDS. Our results indicate that oxidized chalcopyrite surfaces initially containing inactive S n(2-) and S n(2-)/CuS phases were less colonized by A. thiooxidans as compared with surfaces containing active phases (mainly S(0)). Furthermore, it was observed that cells were partially covered by CuS and S(0) phases during biooxidation, especially at highly oxidized chalcopyrite surfaces, suggesting the innocuous effect of CuS phases during A. thiooxidans performance. These results may contribute to understanding the effect of the concomitant formation of refractory secondary phases (as CuS and inactive S n(2-)) during the biooxidation of chalcopyrite by sulfur-oxidizing microorganisms in bioleaching systems. PMID:22584430

  13. Detection and validation of a small broad-host-range plasmid pBBR1MCS-2 for use in genetic manipulation of the extremely acidophilic Acidithiobacillus sp.

    PubMed

    Hao, Likai; Liu, Xiangmei; Wang, Huiyan; Lin, Jianqun; Pang, Xin; Lin, Jianqiang

    2012-09-01

    An efficient genetic system for introducing genes into biomining microorganisms is essential not only to experimentally determine the functions of genes predicted based on bioinformatic analysis, but also for their genetic breeding. In this study, a small broad-host-range vector named pBBR1MCS-2, which does not belong to the IncQ, IncW, or IncP groups, was studied for the feasibility of its use in conjugative gene transfer into extremely acidophilic strains of Acidithiobacillus. To do this, a recombinant plasmid pBBR-tac-Sm, a derivative of pBBR1MCS-2, was constructed and the streptomycin resistant gene (Sm(r)) was used as the reporter gene. Using conjugation, pBBR-tac-Sm was successfully transferred into three tested strains of Acidithiobacillus. Then we measured its transfer frequency, its stability in Acidithiobacillus cells, and the level of resistance to streptomycin of the transconjugants and compared this with the IncQ plasmid pJRD215 control. Our results indicate that pBBR1MCS-2 provides a new and useful tool in the genetic manipulation of Acidithiobacillus strains. PMID:22705922

  14. Preliminary study of treatment of sulphuric pickling water waste from steelmaking by bio-oxidation with Thiobacillus ferrooxidans.

    PubMed

    Garcia, F J; Rubio, A; Sainz, E; Gonzalez, P; Lopez, F A

    1994-08-01

    This report looks at the laboratory-scale recovery of iron oxides (alpha Fe2O3 type) through bio-oxidation with Thiobacillus ferrooxidans of the ferrous sulphate contained in steel industry sulphuric pickling liquors. This is done by calcining iron sulphates and iron and ammonium sulphates obtained from the crystallization of the oxidized solution. The products of the bacterial reaction and the iron oxides are then studied according to calcination temperature. The process carried out produced 50 kg of alpha Fe2O3 per m3 of waste pickling liquor at 700 degrees C with 99.8% weight iron recovery. PMID:7917427

  15. Genome Sequence of the Ethanol-Producing Zymomonas mobilis subsp. mobilis Lectotype Strain ATCC 10988 ▿

    PubMed Central

    Pappas, Katherine M.; Kouvelis, Vassili N.; Saunders, Elizabeth; Brettin, Thomas S.; Bruce, David; Detter, Chris; Balakireva, Mariya; Han, Cliff S.; Savvakis, Giannis; Kyrpides, Nikos C.; Typas, Milton A.

    2011-01-01

    Zymomonas mobilis ATCC 10988 is the type strain of the Z. mobilis subsp. mobilis taxon, members of which are some of the most rigorous ethanol-producing bacteria. Isolated from Agave cactus fermentations in Mexico, ATCC 10988 is one of the first Z. mobilis strains to be described and studied. Its robustness in sucrose-substrate fermentations, physiological characteristics, large number of plasmids, and overall genomic plasticity render this strain important to the study of the species. Here we report the finishing and annotation of the ATCC 10988 chromosomal and plasmid genome. PMID:21725006

  16. Oxidation kinetics and chemostat growth kinetics of Thiobacillus ferrooxidans on tetrathionate and thiosulfate.

    PubMed

    Eccleston, M; Kelly, D P

    1978-06-01

    Growth of Thiobacillus ferrooxidans in batch culture on 10 mM potassium tetrathionate was optimal at pH 2.5 (specific growth rate, 0.092 h-1). Oxygen electrode studies on resting cell suspensions showed that the apparent Km for tetrathionate oxidation (0.13 to 8.33 mM) was pH dependent, suggesting higher substrate affinity at higher pH. Conversely, oxidation rates were greatest at low pH. High substrate concentrations (7.7 to 77 mM) did not affect maximum oxidation rates at pH 3.0, but produced substrate inhibition at other pH values. Tetrathionate-grown cell suspensions also oxidized thiosulfate at pH 2.0 to 4.0. Apparent Km values (1.2 to 25 mM) were of the same order as for tetrathionate, but kinetics were complex. Continuous culture on growth-limiting tetrathionate at pH 2.5, followed by continuous culture on growth-limiting thiosulfate at pH 2.5, indicated true growth yield values (grams [dry weight] per gram-molecule of substrate) of 12.2 and 7.5, and maintenance coefficient values (millimoles of substrate per gram [dry weight) of organisms per hour) of 1.01 and 0.97 for tetrathionate and thiosulfate, respectively. Yield was increased on both media at low dilution rates by increase in CO2 supply. The apparent maintenance coefficient was lowered without affecting YG, suggesting better energy coupling in CO2-rich environments. Prolonged continuous cultivation on tetrathionate or thiosulfate did not affect the ability of the organism to grow subsequently in ferrous iron medium. PMID:26665

  17. Draft Genome Sequence of "Acidibacillus ferrooxidans" ITV01, a Novel Acidophilic Firmicute Isolated from a Chalcopyrite Mine Drainage Site in Brazil.

    PubMed

    Dall'Agnol, Hivana; Ñancucheo, Ivan; Johnson, D Barrie; Oliveira, Renato; Leite, Laura; Pylro, Victor S; Holanda, Roseanne; Grail, Barry; Carvalho, Nelson; Nunes, Gisele Lopes; Tzotzos, George; Fernandes, Gabriel Rocha; Dutra, Julliane; Orellana, Sara Cuadros; Oliveira, Guilherme

    2016-01-01

    Here, we report the draft genome sequence of "Acidibacillus ferrooxidans" strain ITV01, a ferrous iron- and sulfide-mineral-oxidizing, obligate heterotrophic, and acidophilic bacterium affiliated with the phylum Firmicutes. Strain ITV01 was isolated from neutral drainage from a low-grade chalcopyrite from a mine in northern Brazil. PMID:26988062

  18. Genome Sequence of the Acidophilic Ferrous Iron-Oxidizing Isolate Acidithrix ferrooxidans Strain Py-F3, the Proposed Type Strain of the Novel Actinobacterial Genus Acidithrix.

    PubMed

    Eisen, Sebastian; Poehlein, Anja; Johnson, D Barrie; Daniel, Rolf; Schlömann, Michael; Mühling, Martin

    2015-01-01

    Extremely acidophilic iron-oxidizing Gram-positive bacteria comprise species within the phyla Firmicutes and Actinobacteria. Here, we report the 4.02-Mb draft genome of Acidithrix ferrooxidans Py-F3, which was isolated from a stream draining an abandoned copper mine and proposed as the type species of a new genus of Actinobacteria. PMID:25931603

  19. Specific binding of Thiobacillus ferrooxidans RbcR to the intergenic sequence between the rbc operon and the rbcR gene.

    PubMed Central

    Kusano, T; Sugawara, K

    1993-01-01

    The presence of two sets (rbcL1-rbcS1 and rbcL2-rbcS2) of rbc operons has been demonstrated in Thiobacillus ferrooxidans Fe1 (T. Kusano, T. Takeshima, C. Inoue, and K. Sugawara, J. Bacteriol. 173:7313-7323, 1991). A possible regulatory gene, rbcR, 930 bp long and possibly translated into a 309-amino-acid protein, was found upstream from the rbcL1 gene as a single copy. The gene is located divergently to rbcL1 with a 144-bp intergenic sequence. As in the cases of the Chromatium vinosum RbcR and Alcaligenes eutrophus CfxR, T. ferrooxidans RbcR is thought to be a new member of the LysR family, and these proteins share 46.5 and 42.8% identity, respectively. Gel mobility shift assays showed that T. ferrooxidans RbcR, produced in Escherichia coli, binds specifically to the intergenic sequence between rbcL1 and rbcR. Footprinting and site-directed mutagenesis experiments further demonstrated that RbcR binds to overlapping promoter elements of the rbcR and rbcL1 genes. The above data strongly support the participation of RbcR in regulation of the rbcL1-rbcS1 operon and the rbcR gene in T. ferrooxidans. Images PMID:8432695

  20. Purification and some properties of ubiquinol oxidase from obligately chemolithotrophic iron-oxidizing bacterium, Thiobacillus ferrooxidans NASF-1.

    PubMed

    Kamimura, K; Fujii, S; Sugio, T

    2001-01-01

    Ubiquinol-oxidizing activity was detected in an acidophilic chemolithotrophic iron-oxidizing bacterium, T. ferrooxidans. The ubiquinol oxidase was purified 79-fold from plasma membranes of T. ferrooxidans NASF-1 cells. The purified oxidase is composed of two polypeptides with apparent molecular masses of 32,600 and 50,100 Da, as measured by gel electrophoresis in the presence of sodium dodecyl sulfate. The absorption spectrum of the reduced enzyme at room temperature showed big peaks at 530 and 563, and a small broad peak at 635 nm, indicating the involvement of cytochromes b and d. Characteristic peaks of cytochromes a and c were not observed in the spectrum at around 600 and 550 nm, respectively. This enzyme combined with CO, and its CO-reduced minus reduced difference spectrum showed peaks at 409 nm and 563 nm and a trough at 431 nm. These results indicated that the oxidase contained cytochrome b, but the involvement of cytochrome d was not clear. The enzyme catalyzed the oxidations of ubiquinol-2 and reduced N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride. The ubiquinol oxidase activity was activated by the addition of albumin and lecithin to the reaction mixture and inhibited by the respiratory inhibitors KCN, HQNO, NaN3, and antimycin A1, although the enzyme was relatively resistant to KCN, and the divalent cation, Zn2+, compared with ubiquinol oxidases of E. coli. PMID:11272847

  1. Dielectric characterization of forespores isolated from Bacillus megaterium ATCC 19213.

    PubMed Central

    Marquis, R E; Bender, G R; Carstensen, E L; Child, S Z

    1983-01-01

    Isolated stage III forespores of Bacillus megaterium ATCC 19213 in aqueous suspensions were nearly as dehydrated as mature spores, as indicated by low dextran-impermeable volumes of ca. 3.0 ml per g (dry weight) of cells compared with values of ca. 2.6 for mature spores and 7.3 for vegetative cells. The forespores lacked dipicolinate, had only minimal levels of calcium, magnesium, manganese, potassium, and sodium, and were more heat sensitive than vegetative cells. The effective homogeneous conductivities and dielectric constants measured over a frequency range of 1 to 200 MHz indicated that the inherent conductivities of the forespores were unusually low, in keeping with their low mineral contents, but that the forespores could be invaded by environmental ions which could penetrate dielectrically effective membranes. Overall, our findings support the view that the dehydration of a forespore during stage III of sporogenesis may be the result of ion movements out of the forespore into the sporangium. PMID:6401285

  2. L-Lactic Acid Production by Lactobacillus rhamnosus ATCC 10863

    PubMed Central

    Senedese, Ana Lívia Chemeli; Maciel Filho, Rubens; Maciel, Maria Regina Wolf

    2015-01-01

    Lactic acid has been shown to have the most promising application in biomaterials as poly(lactic acid). L. rhamnosus ATCC 10863 that produces L-lactic acid was used to perform the fermentation and molasses was used as substrate. A solution containing 27.6 g/L of sucrose (main composition of molasses) and 3.0 g/L of yeast extract was prepared, considering the final volume of 3,571 mL (14.0% (v/v) inoculum). Batch and fed batch fermentations were performed with temperature of 43.4°C and pH of 5.0. At the fed batch, three molasses feed were applied at 12, 24, and 36 hours. Samples were taken every two hours and the amounts of lactic acid, sucrose, glucose, and fructose were determined by HPLC. The sucrose was barely consumed at both processes; otherwise the glucose and fructose were almost entirely consumed. 16.5 g/L of lactic acid was produced at batch and 22.0 g/L at fed batch. Considering that lactic acid was produced due to the low concentration of the well consumed sugars, the final amount was considerable. The cell growth was checked and no substrate inhibition was observed. A sucrose molasses hydrolysis is suggested to better avail the molasses fermentation with this strain, surely increasing the L-lactic acid. PMID:25922852

  3. New Insights into Chloramphenicol Biosynthesis in Streptomyces venezuelae ATCC 10712

    PubMed Central

    Fernández-Martínez, Lorena T.; Borsetto, Chiara; Gomez-Escribano, Juan Pablo; Bibb, Maureen J.; Al-Bassam, Mahmoud M.; Chandra, Govind

    2014-01-01

    Comparative genome analysis revealed seven uncharacterized genes, sven0909 to sven0915, adjacent to the previously identified chloramphenicol biosynthetic gene cluster (sven0916–sven0928) of Streptomyces venezuelae strain ATCC 10712 that was absent in a closely related Streptomyces strain that does not produce chloramphenicol. Transcriptional analysis suggested that three of these genes might be involved in chloramphenicol production, a prediction confirmed by the construction of deletion mutants. These three genes encode a cluster-associated transcriptional activator (Sven0913), a phosphopantetheinyl transferase (Sven0914), and a Na+/H+ antiporter (Sven0915). Bioinformatic analysis also revealed the presence of a previously undetected gene, sven0925, embedded within the chloramphenicol biosynthetic gene cluster that appears to encode an acyl carrier protein, bringing the number of new genes likely to be involved in chloramphenicol production to four. Microarray experiments and synteny comparisons also suggest that sven0929 is part of the biosynthetic gene cluster. This has allowed us to propose an updated and revised version of the chloramphenicol biosynthetic pathway. PMID:25267678

  4. Highly Hydrolytic Reuteransucrase from Probiotic Lactobacillus reuteri Strain ATCC 55730

    PubMed Central

    Kralj, S.; Stripling, E.; Sanders, P.; van Geel-Schutten, G. H.; Dijkhuizen, L.

    2005-01-01

    Lactobacillus reuteri strain ATCC 55730 (LB BIO) was isolated as a pure culture from a Reuteri tablet purchased from the BioGaia company. This probiotic strain produces a soluble glucan (reuteran), in which the majority of the linkages are of the α-(1→4) glucosidic type (∼70%). This reuteran also contains α-(1→6)- linked glucosyl units and 4,6-disubstituted α-glucosyl units at the branching points. The LB BIO glucansucrase gene (gtfO) was cloned and expressed in Escherichia coli, and the GTFO enzyme was purified. The recombinant GTFO enzyme and the LB BIO culture supernatants synthesized identical glucan polymers with respect to linkage type and size distribution. GTFO thus is a reuteransucrase, responsible for synthesis of this reuteran polymer in LB BIO. The preference of GTFO for synthesizing α-(1→4) linkages is also evident from the oligosaccharides produced from sucrose with different acceptor substrates, e.g., isopanose from isomaltose. GTFO has a relatively high hydrolysis/transferase activity ratio. Complete conversion of 100 mM sucrose by GTFO nevertheless yielded large amounts of reuteran, although more than 50% of sucrose was converted into glucose. This is only the second example of the isolation and characterization of a reuteransucrase and its reuteran product, both found in different L. reuteri strains. GTFO synthesizes a reuteran with the highest amount of α-(1→4) linkages reported to date. PMID:16000808

  5. Microbial ecology of a novel sulphur cycling consortia from AMD: implications for acid generation

    NASA Astrophysics Data System (ADS)

    Loiselle, L. M.; Norlund, K. L.; Hitchcock, A. P.; Warren, L. A.

    2009-05-01

    Recent work1 identified a novel microbial consortia consisting of two bacterial strains common to acid mine drainage (AMD) environments (autotrophic sulphur oxidizer Acidithiobacillus ferrooxidans and heterotrophic Acidiphilium spp.) in an environmental enrichment from a mine tailings lake. The two strains showed a specific spatial arrangement within an EPS macrostructure or "pod" allowing linked metabolic redox cycling of sulphur. Sulphur species characterisation of the pods using scanning transmission X-ray microscopy (STXM) indicated that autotrophic tetrathionate disproportionation by A. ferrooxidans producing colloidal elemental sulphur (S0) is coupled to heterotrophic S0 reduction by Acidiphilium spp. Geochemical modelling of the microbial sulphur reactions indicated that if they are widespread in AMD environments, then global AMD-driven CO2 liberation from mineral weathering have been overestimated by 40-90%1. Given the common co-occurrence of these two bacteria in AMD settings, the purpose of this study was to evaluate if these pods could be induced in the laboratory by pure strains and if so, whether their combined sulphur geochemistry mimicked the previous findings. Laboratory batch experiments assessed the development of pods with pure strain type cultures (A. ferrooxidans ATCC 19859 with mixotroph Acidiphilium acidophilum ATCC 738 or strict heterotroph Acp. cryptum ATCC 2158) using fluorescent in situ hybridization (FISH) imaging. The microbial sulphur geochemistry was characterized under autotrophic conditions identical to those used with the environmental AMD enrichment in which the pods were discovered. Results showed that the combined pure strain A. ferrooxidans and Acp. acidophilum form pods identical in structure to the AMD enrichment. To test the hypothesis that these pods form for mutual metabolic benefit, experiments were performed amending pure strain and AMD enrichment bacterial treatments with organic carbon and/or additional sulphur to

  6. The chromosomal arsenic resistance genes of Thiobacillus ferrooxidans have an unusual arrangement and confer increased arsenic and antimony resistance to Escherichia coli.

    PubMed

    Butcher, B G; Deane, S M; Rawlings, D E

    2000-05-01

    The chromosomal arsenic resistance genes of the acidophilic, chemolithoautotrophic, biomining bacterium Thiobacillus ferrooxidans were cloned and sequenced. Homologues of four arsenic resistance genes, arsB, arsC, arsH, and a putative arsR gene, were identified. The T. ferrooxidans arsB (arsenite export) and arsC (arsenate reductase) gene products were functional when they were cloned in an Escherichia coli ars deletion mutant and conferred increased resistance to arsenite, arsenate, and antimony. Therefore, despite the fact that the ars genes originated from an obligately acidophilic bacterium, they were functional in E. coli. Although T. ferrooxidans is gram negative, its ArsC was more closely related to the ArsC molecules of gram-positive bacteria. Furthermore, a functional trxA (thioredoxin) gene was required for ArsC-mediated arsenate resistance in E. coli; this finding confirmed the gram-positive ArsC-like status of this resistance and indicated that the division of ArsC molecules based on Gram staining results is artificial. Although arsH was expressed in an E. coli-derived in vitro transcription-translation system, ArsH was not required for and did not enhance arsenic resistance in E. coli. The T. ferrooxidans ars genes were arranged in an unusual manner, and the putative arsR and arsC genes and the arsBH genes were translated in opposite directions. This divergent orientation was conserved in the four T. ferrooxidans strains investigated. PMID:10788346

  7. Antifungal effects of citronella oil against Aspergillus niger ATCC 16404.

    PubMed

    Li, Wen-Ru; Shi, Qing-Shan; Ouyang, You-Sheng; Chen, Yi-Ben; Duan, Shun-Shan

    2013-08-01

    Essential oils are aromatic oily liquids obtained from some aromatic plant materials. Certain essential oils such as citronella oil contain antifungal activity, but the antifungal effect is still unknown. In this study, we explored the antifungal effect of citronella oil with Aspergillus niger ATCC 16404. The antifungal activity of citronella oil on conidia of A. niger was determined by poisoned food technique, broth dilution method, and disc volatility method. Experimental results indicated that the citronella oil has strong antifungal activity: 0.125 (v/v) and 0.25 % (v/v) citronella oil inhibited the growth of 5 × 10⁵ spore/ml conidia separately for 7 and 28 days while 0.5 % (v/v) citronella oil could completely kill the conidia of 5 × 10⁵ spore/ml. Moreover, the fungicidal kinetic curves revealed that more than 90 % conidia (initial concentration is 5 × 10⁵ spore/ml) were killed in all the treatments with 0.125 to 2 % citronella oil after 24 h. Furthermore, with increase of citronella oil concentration and treatment time, the antifungal activity was increased correspondingly. The 0.5 % (v/v) concentration of citronella oil was a threshold to kill the conidia thoroughly. The surviving conidia treated with 0.5 to 2 % citronella oil decreased by an order of magnitude every day, and no fungus survived after 10 days. With light microscope, scanning electron microscope, and transmission electron microscope, we found that citronella oil could lead to irreversible alteration of the hyphae and conidia. Based on our observation, we hypothesized that the citronella oil destroyed the cell wall of the A. niger hyphae, passed through the cell membrane, penetrated into the cytoplasm, and acted on the main organelles. Subsequently, the hyphae was collapsed and squashed due to large cytoplasm loss, and the organelles were severely destroyed. Similarly, citronella oil could lead to the rupture of hard cell wall and then act on the sporoplasm to kill the

  8. The Zur regulon of Corynebacterium glutamicum ATCC 13032

    PubMed Central

    2010-01-01

    Background Zinc is considered as an essential element for all living organisms, but it can be toxic at large concentrations. Bacteria therefore tightly regulate zinc metabolism. The Cg2502 protein of Corynebacterium glutamicum was a candidate to control zinc metabolism in this species, since it was classified as metalloregulator of the zinc uptake regulator (Zur) subgroup of the ferric uptake regulator (Fur) family of DNA-binding transcription regulators. Results The cg2502 (zur) gene was deleted in the chromosome of C. glutamicum ATCC 13032 by an allelic exchange procedure to generate the zur-deficient mutant C. glutamicum JS2502. Whole-genome DNA microarray hybridizations and real-time RT-PCR assays comparing the gene expression in C. glutamicum JS2502 with that of the wild-type strain detected 18 genes with enhanced expression in the zur mutant. The expression data were combined with results from cross-genome comparisons of shared regulatory sites, revealing the presence of candidate Zur-binding sites in the mapped promoter regions of five transcription units encoding components of potential zinc ABC-type transporters (cg0041-cg0042/cg0043; cg2911-cg2912-cg2913), a putative secreted protein (cg0040), a putative oxidoreductase (cg0795), and a putative P-loop GTPase of the COG0523 protein family (cg0794). Enhanced transcript levels of the respective genes in C. glutamicum JS2502 were verified by real-time RT-PCR, and complementation of the mutant with a wild-type zur gene reversed the effect of differential gene expression. The zinc-dependent expression of the putative cg0042 and cg2911 operons was detected in vivo with a gfp reporter system. Moreover, the zinc-dependent binding of purified Zur protein to double-stranded 40-mer oligonucleotides containing candidate Zur-binding sites was demonstrated in vitro by DNA band shift assays. Conclusion Whole-genome expression profiling and DNA band shift assays demonstrated that Zur directly represses in a zinc

  9. Transcriptomic analysis of Clostridium thermocellum ATCC 27405 cellulose fermentation

    SciTech Connect

    McKeown, Catherine K; Brown, Steven D

    2011-01-01

    The ability of Clostridium thermocellum ATCC 27405 wild-type strain to hydrolyze cellulose and ferment the degradation products directly to ethanol and other metabolic byproducts makes it an attractive candidate for consolidated bioprocessing of cellulosic biomass to biofuels. In this study, whole-genome microarrays were used to investigate the expression of C. thermocellum mRNA during growth on crystalline cellulose in controlled replicate batch fermentations. A time-series analysis of gene expression revealed changes in transcript levels of {approx}40% of genes ({approx}1300 out of 3198 ORFs encoded in the genome) during transition from early-exponential to late-stationary phase. K-means clustering of genes with statistically significant changes in transcript levels identified six distinct clusters of temporal expression. Broadly, genes involved in energy production, translation, glycolysis and amino acid, nucleotide and coenzyme metabolism displayed a decreasing trend in gene expression as cells entered stationary phase. In comparison, genes involved in cell structure and motility, chemotaxis, signal transduction and transcription showed an increasing trend in gene expression. Hierarchical clustering of cellulosome-related genes highlighted temporal changes in composition of this multi-enzyme complex during batch growth on crystalline cellulose, with increased expression of several genes encoding hydrolytic enzymes involved in degradation of non-cellulosic substrates in stationary phase. Overall, the results suggest that under low substrate availability, growth slows due to decreased metabolic potential and C. thermocellum alters its gene expression to (i) modulate the composition of cellulosomes that are released into the environment with an increased proportion of enzymes than can efficiently degrade plant polysaccharides other than cellulose, (ii) enhance signal transduction and chemotaxis mechanisms perhaps to sense the oligosaccharide hydrolysis products

  10. Enhancement of growth and ferrous iron oxidation rates of T. ferrooxidans by electrochemical reduction of ferric iron

    SciTech Connect

    Yunker, S.B.; Radovich, J.M.

    1986-01-01

    Thiobacillus ferrooxidans, the bacterium most widely used in bioleaching or microbial desulfurization of coal, was grown in an electrolytic bioreactor containing a synthetic, ferrous sulfate medium. Passage of current through the medium reduced the bacterially generated ferric iron to the ferrous iron substrate. When used in conjunction with an inoculum that had been adapted to the electrolytic growth conditions, this technique increased the protein (cell) concentration by 3.7 times, increased the protein (cell) production rate by 6.5 times, increased the yield coefficient (cellular efficiency) by 8.0 times, and increased the ferrous iron oxidation rate by 1.5 times at 29/sup 0/C, compared with conventional cultivation techniques. A Monod-type equation with accepted values for the maximum specific growth rate could not account for the increased growth rate under electrolytic conditions.

  11. Effects of Cinnabar on Pyrite Oxidation by Thiobacillus ferrooxidans and Cinnabar Mobilization by a Mercury-Resistant Strain

    PubMed Central

    Baldi, Franco; Olson, Gregory J.

    1987-01-01

    The effect of cinnabar on pyrite oxidation by mercury-sensitive and mercury-resistant strains of Thiobacillus ferrooxidans was investigated by using percolation columns. Mercury-resistant strains oxidized pyrite in pyrite-cinnabar mixtures (1 and 10%, wt/wt), whereas a mercury-sensitive strain did not. Elemental mercury was produced by the mercury-resistant strains growing in the pyrite-cinnabar mixtures in percolation columns and in flasks containing cinnabar only. Manometric experiments showed that cinnabar had little effect on oxygen uptake of mercury-sensitive or mercury-resistant cells growing on ferrous sulfate, pyrite, or pyrite-ferrous sulfate mixtures. In addition, shake flask leaching experiments showed that cinnabar had little effect on pyrite oxidation at 1% (wt/wt) but inhibited growth of mercury-sensitive and mercury-resistant strains at 10%. Mercury-resistant strains were unable to grow on cinnabar as an energy source. PMID:16347321

  12. Detergent composition comprising a cellulase containing cell-free fermentate produced from microorganism ATCC 55702 or mutant thereof

    DOEpatents

    Dees, H. Craig

    1998-01-01

    Bacteria which produce large amounts of a cellulase-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

  13. Detergent composition comprising a cellulase containing cell-free fermentate produced from microorganism ATCC 55702 or mutant thereof

    DOEpatents

    Dees, H.C.

    1998-07-14

    Bacteria which produce large amounts of a cellulase-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques. 5 figs.

  14. Leaching of zinc sulfide by Thiobacillus ferrooxidans: bacterial oxidation of the sulfur product layer increases the rate of zinc sulfide dissolution at high concentrations of ferrous ions.

    PubMed

    Fowler, T A; Crundwell, F K

    1999-12-01

    This paper reports the results of leaching experiments conducted with and without Thiobacillus ferrooxidans at the same conditions in solution. The extent of leaching of ZnS with bacteria is significantly higher than that without bacteria at high concentrations of ferrous ions. A porous layer of elemental sulfur is present on the surfaces of the chemically leached particles, while no sulfur is present on the surfaces of the bacterially leached particles. The analysis of the data using the shrinking-core model shows that the chemical leaching of ZnS is limited by the diffusion of ferrous ions through the sulfur product layer at high concentrations of ferrous ions. The analysis of the data shows that diffusion through the product layer does not limit the rate of dissolution when bacteria are present. This suggests that the action of T. ferrooxidans in oxidizing the sulfur formed on the particle surface is to remove the barrier to diffusion by ferrous ions. PMID:10583978

  15. Molecular cloning, sequencing, and expression of omp-40, the gene coding for the major outer membrane protein from the acidophilic bacterium Thiobacillus ferrooxidans.

    PubMed

    Guiliani, N; Jerez, C A

    2000-06-01

    Thiobacillus ferrooxidans is one of the chemolithoautotrophic bacteria important in industrial biomining operations. Some of the surface components of this microorganism are probably involved in adaptation to their acidic environment and in bacterium-mineral interactions. We have isolated and characterized omp40, the gene coding for the major outer membrane protein from T. ferrooxidans. The deduced amino acid sequence of the Omp40 protein has 382 amino acids and a calculated molecular weight of 40,095.7. Omp40 forms an oligomeric structure of about 120 kDa that dissociates into the monomer (40 kDa) by heating in the presence of sodium dodecyl sulfate. The degree of identity of Omp40 amino acid sequence to porins from enterobacteria was only 22%. Nevertheless, multiple alignments of this sequence with those from several OmpC porins showed several important features conserved in the T. ferrooxidans surface protein, such as the approximate locations of 16 transmembrane beta strands, eight loops, including a large external L3 loop, and eight turns which allowed us to propose a putative 16-stranded beta-barrel porin structure for the protein. These results together with the previously known capacity of Omp40 to form ion channels in planar lipid bilayers strongly support its role as a porin in this chemolithoautotrophic acidophilic microorganism. Some characteristics of the Omp40 protein, such as the presence of a putative L3 loop with an estimated isoelectric point of 7.21 allow us to speculate that this can be the result of an adaptation of the acidophilic T. ferrooxidans to prevent free movement of protons across its outer membrane. PMID:10831405

  16. Specific point mutations in Lactobacillus casei ATCC 27139 cause a phenotype switch from Lac- to Lac+.

    PubMed

    Tsai, Yu-Kuo; Chen, Hung-Wen; Lo, Ta-Chun; Lin, Thy-Hou

    2009-03-01

    Lactose metabolism is a changeable phenotype in strains of Lactobacillus casei. In this study, we found that L. casei ATCC 27139 was unable to utilize lactose. However, when exposed to lactose as the sole carbon source, spontaneous Lac(+) clones could be obtained. A gene cluster (lacTEGF-galKETRM) involved in the metabolism of lactose and galactose in L. casei ATCC 27139 (Lac(-)) and its Lac(+) revertant (designated strain R1) was sequenced and characterized. We found that only one nucleotide, located in the lacTEGF promoter (lacTp), of the two lac-gal gene clusters was different. The protein sequence identity between the lac-gal gene cluster and those reported previously for some L. casei (Lac(+)) strains was high; namely, 96-100 % identity was found and no premature stop codon was identified. A single point mutation located within the lacTp promoter region was also detected for each of the 41 other independently isolated Lac(+) revertants of L. casei ATCC 27139. The revertants could be divided into six classes based on the positions of the point mutations detected. Primer extension experiments conducted on transcription from lacTp revealed that the lacTp promoter of these six classes of Lac(+) revertants was functional, while that of L. casei ATCC 27139 was not. Northern blotting experiments further confirmed that the lacTEGF operon of strain R1 was induced by lactose but suppressed by glucose, whereas no blotting signal was ever detected for L. casei ATCC 27139. These results suggest that a single point mutation in the lacTp promoter was able to restore the transcription of a fully functional lacTEGF operon and cause a phenotype switch from Lac(-) to Lac(+) for L. casei ATCC 27139. PMID:19246746

  17. Expression of Clostridium acetobutylicum ATCC 824 Genes in Escherichia coli for Acetone Production and Acetate Detoxification

    PubMed Central

    Bermejo, Lourdes L.; Welker, Neil E.; Papoutsakis, Eleftherios T.

    1998-01-01

    A synthetic acetone operon (ace4) composed of four Clostridium acetobutylicum ATCC 824 genes (adc, ctfAB, and thl, coding for the acetoacetate decarboxylase, coenzyme A transferase, and thiolase, respectively) under the control of the thl promoter was constructed and was introduced into Escherichia coli on vector pACT. Acetone production demonstrated that ace4 is expressed in E. coli and resulted in the reduction of acetic acid levels in the fermentation broth. Since different E. coli strains vary significantly in their growth characteristics and acetate metabolism, ace4 was expressed in three E. coli strains: ER2275, ATCC 11303, and MC1060. Shake flask cultures of MC1060(pACT) produced ca. 2 mM acetone, while both strains ER2275(pACT) and ATCC 11303(pACT) produced ca. 40 mM acetone. Glucose-fed cultures of strain ATCC 11303(pACT) resulted in a 150% increase in acetone titers compared to those of batch shake flask cultures. External addition of sodium acetate to glucose-fed cultures of ATCC 11303(pACT) resulted in further increased acetone titers. In bioreactor studies, acidic conditions (pH 5.5 versus 6.5) improved acetone production. Despite the substantial acetone evaporation due to aeration and agitation in the bioreactor, 125 to 154 mM acetone accumulated in ATCC 11303(pACT) fermentations. These acetone titers are equal to or higher than those produced by wild-type C. acetobutylicum. This is the first study to demonstrate the ability to use clostridial genes in nonclostridial hosts for solvent production. In addition, acetone-producing E. coli strains may be useful hosts for recombinant protein production in that detrimental acetate accumulation can be avoided. PMID:9501448

  18. Relationship between Glycopeptide Production and Resistance in the Actinomycete Nonomuraea sp. ATCC 39727

    PubMed Central

    Binda, Elisa; Carrano, Lucia; Bibb, Mervyn; Marinelli, Flavia

    2014-01-01

    Glycopeptides and β-lactams inhibit bacterial peptidoglycan synthesis in Gram-positive bacteria; resistance to these antibiotics is studied intensively in enterococci and staphylococci because of their relevance to infectious disease. Much less is known about antibiotic resistance in glycopeptide-producing actinomycetes that are likely to represent the evolutionary source of resistance determinants found in bacterial pathogens. Nonomuraea sp. ATCC 39727, the producer of A40926 (the precursor for the semisynthetic dalbavancin), does not harbor the canonical vanHAX genes. Consequently, we investigated the role of the β-lactam-sensitive d,d-peptidase/d,d-carboxypeptidase encoded by vanYn, the only van-like gene found in the A40926 biosynthetic gene cluster, in conferring immunity to the antibiotic in Nonomuraea sp. ATCC 39727. Taking advantage of the tools developed recently to genetically manipulate this uncommon actinomycete, we varied vanYn gene dosage and expressed vanHatAatXat from the teicoplanin producer Actinoplanes teichomyceticus in Nonomuraea sp. ATCC 39727. Knocking out vanYn, complementing a vanYn mutant, or duplicating vanYn had no effect on growth but influenced antibiotic resistance and, in the cases of complementation and duplication, antibiotic production. Nonomuraea sp. ATCC 39727 was found to be resistant to penicillins, but its glycopeptide resistance was diminished in the presence of penicillin G, which inhibits VanYn activity. The heterologous expression of vanHatAatXat increased A40926 resistance in Nonomuraea sp. ATCC 39727 but did not increase antibiotic production, indicating that the level of antibiotic production is not directly determined by the level of resistance. The vanYn-based self-resistance in Nonomuraea sp. ATCC 39727 resembles the glycopeptide resistance mechanism described recently in mutants of Enterococcus faecium selected in vitro for high-level resistance to glycopeptides and penicillins. PMID:24957828

  19. Genome sequence and comparative genome analysis of Pseudomonas syringae pv. syringae type strain ATCC 19310.

    PubMed

    Park, Yong-Soon; Jeong, Haeyoung; Sim, Young Mi; Yi, Hwe-Su; Ryu, Choong-Min

    2014-04-01

    Pseudomonas syringae pv. syringae (Psy) is a major bacterial pathogen of many economically important plant species. Despite the severity of its impact, the genome sequence of the type strain has not been reported. Here, we present the draft genome sequence of Psy ATCC 19310. Comparative genomic analysis revealed that Psy ATCC 19310 is closely related to Psy B728a. However, only a few type III effectors, which are key virulence factors, are shared by the two strains, indicating the possibility of host-pathogen specificity and genome dynamics, even under the pathovar level. PMID:24444998

  20. Genome sequence and plasmid transformation of the model high-yield bacterial cellulose producer Gluconacetobacter hansenii ATCC 53582

    NASA Astrophysics Data System (ADS)

    Florea, Michael; Reeve, Benjamin; Abbott, James; Freemont, Paul S.; Ellis, Tom

    2016-03-01

    Bacterial cellulose is a strong, highly pure form of cellulose that is used in a range of applications in industry, consumer goods and medicine. Gluconacetobacter hansenii ATCC 53582 is one of the highest reported bacterial cellulose producing strains and has been used as a model organism in numerous studies of bacterial cellulose production and studies aiming to increased cellulose productivity. Here we present a high-quality draft genome sequence for G. hansenii ATCC 53582 and find that in addition to the previously described cellulose synthase operon, ATCC 53582 contains two additional cellulose synthase operons and several previously undescribed genes associated with cellulose production. In parallel, we also develop optimized protocols and identify plasmid backbones suitable for transformation of ATCC 53582, albeit with low efficiencies. Together, these results provide important information for further studies into cellulose synthesis and for future studies aiming to genetically engineer G. hansenii ATCC 53582 for increased cellulose productivity.

  1. Genome sequence and plasmid transformation of the model high-yield bacterial cellulose producer Gluconacetobacter hansenii ATCC 53582.

    PubMed

    Florea, Michael; Reeve, Benjamin; Abbott, James; Freemont, Paul S; Ellis, Tom

    2016-01-01

    Bacterial cellulose is a strong, highly pure form of cellulose that is used in a range of applications in industry, consumer goods and medicine. Gluconacetobacter hansenii ATCC 53582 is one of the highest reported bacterial cellulose producing strains and has been used as a model organism in numerous studies of bacterial cellulose production and studies aiming to increased cellulose productivity. Here we present a high-quality draft genome sequence for G. hansenii ATCC 53582 and find that in addition to the previously described cellulose synthase operon, ATCC 53582 contains two additional cellulose synthase operons and several previously undescribed genes associated with cellulose production. In parallel, we also develop optimized protocols and identify plasmid backbones suitable for transformation of ATCC 53582, albeit with low efficiencies. Together, these results provide important information for further studies into cellulose synthesis and for future studies aiming to genetically engineer G. hansenii ATCC 53582 for increased cellulose productivity. PMID:27010592

  2. Genome sequence and plasmid transformation of the model high-yield bacterial cellulose producer Gluconacetobacter hansenii ATCC 53582

    PubMed Central

    Florea, Michael; Reeve, Benjamin; Abbott, James; Freemont, Paul S.; Ellis, Tom

    2016-01-01

    Bacterial cellulose is a strong, highly pure form of cellulose that is used in a range of applications in industry, consumer goods and medicine. Gluconacetobacter hansenii ATCC 53582 is one of the highest reported bacterial cellulose producing strains and has been used as a model organism in numerous studies of bacterial cellulose production and studies aiming to increased cellulose productivity. Here we present a high-quality draft genome sequence for G. hansenii ATCC 53582 and find that in addition to the previously described cellulose synthase operon, ATCC 53582 contains two additional cellulose synthase operons and several previously undescribed genes associated with cellulose production. In parallel, we also develop optimized protocols and identify plasmid backbones suitable for transformation of ATCC 53582, albeit with low efficiencies. Together, these results provide important information for further studies into cellulose synthesis and for future studies aiming to genetically engineer G. hansenii ATCC 53582 for increased cellulose productivity. PMID:27010592

  3. Multigene disruption in undomesticated Bacillus subtilis ATCC 6051a using the CRISPR/Cas9 system.

    PubMed

    Zhang, Kang; Duan, Xuguo; Wu, Jing

    2016-01-01

    Bacillus subtilis ATCC 6051a is an undomesticated strain used in the industrial production of enzymes. Because it is poorly transformable, genetic manipulation in this strain requires a highly efficient genome editing method. In this study, a Streptococcus pyogenes CRISPR/Cas9 system consisting of an all-in-one knockout plasmid containing a target-specific guide RNA, cas9, and a homologous repair template was established for highly efficient gene disruption in B. subtilis ATCC 6051a. With an efficiency of 33% to 53%, this system was used to disrupt the srfC, spoIIAC, nprE, aprE and amyE genes of B. subtilis ATCC 6051a, which hamper its use in industrial fermentation. Compared with B. subtilis ATCC 6051a, the final mutant, BS5 (ΔsrfC, ΔspoIIAC, ΔnprE, ΔaprE, ΔamyE), produces much less foam during fermentation, displays greater resistant to spore formation, and secretes 2.5-fold more β-cyclodextrin glycosyltransferase into the fermentation medium. Thus, the CRISPR/Cas9 system proved to be a powerful tool for targeted genome editing in an industrially relevant, poorly transformable strain. PMID:27305971

  4. Genome sequence of the vertebrate gut symbiont Lactobacillus reuteri ATCC 53608.

    PubMed

    Heavens, Darren; Tailford, Louise E; Crossman, Lisa; Jeffers, Faye; Mackenzie, Donald A; Caccamo, Mario; Juge, Nathalie

    2011-08-01

    Lactobacillus reuteri, inhabiting the gastrointestinal tracts of a range of vertebrates, is a true symbiont with effects established as beneficial to the host. Here we describe the draft genome of L. reuteri ATCC 53608, isolated from a pig. The genome sequence provides important insights into the evolutionary changes underlying host specialization. PMID:21622738

  5. Multigene disruption in undomesticated Bacillus subtilis ATCC 6051a using the CRISPR/Cas9 system

    PubMed Central

    Zhang, Kang; Duan, Xuguo; Wu, Jing

    2016-01-01

    Bacillus subtilis ATCC 6051a is an undomesticated strain used in the industrial production of enzymes. Because it is poorly transformable, genetic manipulation in this strain requires a highly efficient genome editing method. In this study, a Streptococcus pyogenes CRISPR/Cas9 system consisting of an all-in-one knockout plasmid containing a target-specific guide RNA, cas9, and a homologous repair template was established for highly efficient gene disruption in B. subtilis ATCC 6051a. With an efficiency of 33% to 53%, this system was used to disrupt the srfC, spoIIAC, nprE, aprE and amyE genes of B. subtilis ATCC 6051a, which hamper its use in industrial fermentation. Compared with B. subtilis ATCC 6051a, the final mutant, BS5 (ΔsrfC, ΔspoIIAC, ΔnprE, ΔaprE, ΔamyE), produces much less foam during fermentation, displays greater resistant to spore formation, and secretes 2.5-fold more β-cyclodextrin glycosyltransferase into the fermentation medium. Thus, the CRISPR/Cas9 system proved to be a powerful tool for targeted genome editing in an industrially relevant, poorly transformable strain. PMID:27305971

  6. Interaction of Pseudomonas putida ATCC 12633 and Bacteriophage gh-1 in Berea Sandstone Rock.

    PubMed

    Chang, P L; Yen, T F

    1985-12-01

    Measurements of the passage of Pseudomonas putida ATCC 12633 and a phage-resistant mutant through Berea sandstone rock were made. When bacteriophage gh-1 was adsorbed within the rock matrix, a reduction in the passage of the susceptible but not the resistant cells through the rock was observed. PMID:16346956

  7. Interaction of Pseudomonas putida ATCC 12633 and Bacteriophage gh-1 in Berea Sandstone Rock

    PubMed Central

    Chang, Philip Lee; Yen, Teh Fu

    1985-01-01

    Measurements of the passage of Pseudomonas putida ATCC 12633 and a phage-resistant mutant through Berea sandstone rock were made. When bacteriophage gh-1 was adsorbed within the rock matrix, a reduction in the passage of the susceptible but not the resistant cells through the rock was observed. PMID:16346956

  8. Complete genome sequence of Streptococcus equi subsp. zooepidemicus strain ATCC 35246.

    PubMed

    Ma, Zhe; Geng, Jianing; Zhang, Hui; Yu, Haiying; Yi, Li; Lei, Meng; Lu, Cheng-ping; Fan, Hong-jie; Hu, Songnian

    2011-10-01

    Streptococcus equi subsp. zooepidemicus is an opportunistic pathogen. It has caused a very large economic loss in the swine industry of China and has become a threat to human health. We announce the complete genome sequence of S. equi subsp. zooepidemicus strain ATCC 35246, which provides opportunities to understand its pathogenesis mechanism and genetic basis. PMID:21914890

  9. Draft Genome Assembly of Ralstonia pickettii Type Strain K-288 (ATCC 27853)

    PubMed Central

    Daligault, H. E.; Davenport, K. W.; Minogue, T. D.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Gibbons, H. S.; Jaissle, J.; Lo, C.-C.; Meincke, L.; Munk, A. C.; Rosenzweig, C. N.

    2014-01-01

    We present the genome assembly of Ralstonia pickettii K-288 (ATCC 27511), consisting of 27 contigs placed into a single scaffold. This 4.76-Mbp genome has 64.0% G+C content and 4,425 coding sequences. Because this is the type strain, inclusion of its data set among other Ralstonia genomes should provide a historical genomic perspective. PMID:25258272

  10. Draft Genome Assembly of Ralstonia pickettii Type Strain K-288 (ATCC 27853).

    PubMed

    Daligault, H E; Davenport, K W; Minogue, T D; Broomall, S M; Bruce, D C; Chain, P S; Coyne, S R; Gibbons, H S; Jaissle, J; Lo, C-C; Meincke, L; Munk, A C; Rosenzweig, C N; Johnson, S L

    2014-01-01

    We present the genome assembly of Ralstonia pickettii K-288 (ATCC 27511), consisting of 27 contigs placed into a single scaffold. This 4.76-Mbp genome has 64.0% G+C content and 4,425 coding sequences. Because this is the type strain, inclusion of its data set among other Ralstonia genomes should provide a historical genomic perspective. PMID:25258272

  11. Genome Assembly of Shigella flexneri ATCC 12022, a Quality Control Reference Strain

    PubMed Central

    Daligault, H. E.; Davenport, K. W.; Minogue, T. D.; Bishop-Lilly, K. A.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Freitas, T.; Frey, K. G.; Gibbons, H. S.; Jaissle, J.; Lo, C.-C.; Meincke, L.; Munk, A. C.; Redden, C. L.; Rosenzweig, C. N.

    2014-01-01

    Shigella flexneri causes shigellosis, severe and potentially life-threatening diarrhea, and accounts for 18% of shigellosis cases in the United States. Here, we present the 4.51-Mbp genome assembly of S. flexneri ATCC 12022, a quality control and reference strain, in 10 scaffolds. PMID:25359907

  12. Complete Genome Assembly of Escherichia coli ATCC 25922, a Serotype O6 Reference Strain.

    PubMed

    Minogue, T D; Daligault, H A; Davenport, K W; Bishop-Lilly, K A; Broomall, S M; Bruce, D C; Chain, P S; Chertkov, O; Coyne, S R; Freitas, T; Frey, K G; Gibbons, H S; Jaissle, J; Redden, C L; Rosenzweig, C N; Xu, Y; Johnson, S L

    2014-01-01

    We present the complete genome assembly of Escherichia coli ATCC 25922 as submitted to NCBI under accession no. CP009072. This strain was originally isolated from a clinical sample in Seattle, Washington (1946), and is often used in quality control testing. The assembled genome is 5.20 Mb (50.4% G+C content) and includes two plasmids. PMID:25291776

  13. Complete Genome Assembly of Escherichia coli ATCC 25922, a Serotype O6 Reference Strain

    PubMed Central

    Minogue, T. D.; Daligault, H. A.; Davenport, K. W.; Bishop-Lilly, K. A.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Chertkov, O.; Coyne, S. R.; Freitas, T.; Frey, K. G.; Gibbons, H. S.; Jaissle, J.; Redden, C. L.; Rosenzweig, C. N.; Xu, Y.

    2014-01-01

    We present the complete genome assembly of Escherichia coli ATCC 25922 as submitted to NCBI under accession no. CP009072. This strain was originally isolated from a clinical sample in Seattle, Washington (1946), and is often used in quality control testing. The assembled genome is 5.20 Mb (50.4% G+C content) and includes two plasmids. PMID:25291776

  14. Genome Assembly of Shigella flexneri ATCC 12022, a Quality Control Reference Strain.

    PubMed

    Daligault, H E; Davenport, K W; Minogue, T D; Bishop-Lilly, K A; Broomall, S M; Bruce, D C; Chain, P S; Coyne, S R; Freitas, T; Frey, K G; Gibbons, H S; Jaissle, J; Lo, C-C; Meincke, L; Munk, A C; Redden, C L; Rosenzweig, C N; Johnson, S L

    2014-01-01

    Shigella flexneri causes shigellosis, severe and potentially life-threatening diarrhea, and accounts for 18% of shigellosis cases in the United States. Here, we present the 4.51-Mbp genome assembly of S. flexneri ATCC 12022, a quality control and reference strain, in 10 scaffolds. PMID:25359907

  15. Complete Genome Sequence of Stenotrophomonas maltophilia Type Strain 810-2 (ATCC 13637).

    PubMed

    Davenport, K W; Daligault, H E; Minogue, T D; Broomall, S M; Bruce, D C; Chain, P S; Coyne, S R; Gibbons, H S; Jaissle, J; Li, P-E; Rosenzweig, C N; Scholz, M B; Johnson, S L

    2014-01-01

    An emerging nosocomial pathogen, Stenotrophomonas maltophila has a high mortality rate in those it infects. Here, we present the complete genome sequence of Stenotrophomonas maltophilia 810-2 (ATCC 13637), the type strain of the species. The 5-Mb (66.1% G+C content) genome has been deposited in NCBI under accession number CP008838. PMID:25258273

  16. Complete Genome Sequence of Stenotrophomonas maltophilia Type Strain 810-2 (ATCC 13637)

    PubMed Central

    Davenport, K. W.; Daligault, H. E.; Minogue, T. D.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Gibbons, H. S.; Jaissle, J.; Li, P.-E.; Rosenzweig, C. N.; Scholz, M. B.

    2014-01-01

    An emerging nosocomial pathogen, Stenotrophomonas maltophila has a high mortality rate in those it infects. Here, we present the complete genome sequence of Stenotrophomonas maltophilia 810-2 (ATCC 13637), the type strain of the species. The 5-Mb (66.1% G+C content) genome has been deposited in NCBI under accession number CP008838. PMID:25258273

  17. Complete Genome Sequence of Thiostrepton-Producing Streptomyces laurentii ATCC 31255.

    PubMed

    Doi, Katsumi; Fujino, Yasuhiro; Nagayoshi, Yuko; Ohshima, Toshihisa; Ogata, Seiya

    2016-01-01

    Streptomyces laurentii ATCC 31255 produces thiostrepton, a thiopeptide class antibiotic. Here, we report the complete genome sequence for this strain, which contains a total of 8,032,664 bp, 7,452 predicted coding sequences, and a G+C content of 72.3%. PMID:27257211

  18. Draft Genome Sequence of the Probiotic Yeast Saccharomyces cerevisiae var. boulardii Strain ATCC MYA-796

    PubMed Central

    Marques, E. T. A.; Franco, G. R.

    2014-01-01

    Saccharomyces boulardii is the only yeast approved as a probiotic for human consumption. Here, we report the draft genome sequence of the strain ATCC MYA-796, derived from the French Ultra Levure probiotic drug. The genome has a size of 11.6 Mb with 5,305 putative open reading frames predicted. PMID:25523784

  19. Genome Sequence of meso-2,3-Butanediol-Producing Strain Serratia marcescens ATCC 14041

    PubMed Central

    Li, Lixiang; Wang, Yu; Li, Kun; Su, Fei; Ma, Cuiqing

    2014-01-01

    Serratia marcescens strain ATCC 14041 was found to be an efficient meso-2,3-butanediol (meso-2,3-BD) producer from glucose and sucrose. Here we present a 5.0-Mb assembly of its genome. We have annotated 4 coding sequences (CDSs) for meso-2,3-BD fermentation and 2 complete operons including 6 CDSs for sucrose utilization. PMID:24948764

  20. Complete Genome Sequence of Brachyspira hyodysenteriae Type Strain B-78 (ATCC 27164)

    PubMed Central

    Mirajkar, Nandita S.; Johnson, Timothy J.

    2016-01-01

    Reported herein is the complete genome sequence of the type strain B-78 (ATCC 27164) of Brachyspira hyodysenteriae, the etiological agent of swine dysentery. The 3.1-Mb genome consists of a 3.056-Mb chromosome and a 45-kb plasmid, with 2,617 protein-coding genes, 39 RNA genes, and 40 pseudogenes. PMID:27540064

  1. Complete Genome Sequence of the Bioluminescent Marine Bacterium Vibrio harveyi ATCC 33843 (392 [MAV]).

    PubMed

    Wang, Zheng; Hervey, W Judson; Kim, Seongwon; Lin, Baochuan; Vora, Gary J

    2015-01-01

    Vibrio harveyi is a Gram-negative marine γ-proteobacterium that is known to be a formidable pathogen of aquatic animals and is a model organism for the study of bacterial bioluminescence and quorum sensing. In this report, we describe the complete genome sequence of the most studied strain of this species: V. harveyi ATCC 33843 (392 [MAV]). PMID:25635019

  2. Complete Genome Sequence of the Bioluminescent Marine Bacterium Vibrio harveyi ATCC 33843 (392 [MAV])

    PubMed Central

    Wang, Zheng; Hervey, W. Judson; Kim, Seongwon; Lin, Baochuan

    2015-01-01

    Vibrio harveyi is a Gram-negative marine γ-proteobacterium that is known to be a formidable pathogen of aquatic animals and is a model organism for the study of bacterial bioluminescence and quorum sensing. In this report, we describe the complete genome sequence of the most studied strain of this species: V. harveyi ATCC 33843 (392 [MAV]). PMID:25635019

  3. Draft Genome Sequence of a Metronidazole-Resistant Derivative of Gardnerella vaginalis Strain ATCC 14019

    PubMed Central

    Schuyler, Jessica A.; Mordechai, Eli; Adelson, Martin E.; Gygax, Scott E.

    2015-01-01

    We report the genome sequence of a metronidazole-resistant derivative of Gardnerella vaginalis ATCC 14019. This strain was obtained after serial selection to increase the MIC from 4 to ≥500 µg/ml. Two coding changes, in genes encoding a response regulator and an NAD+ synthetase, arose during selection. PMID:26564054

  4. Genome Sequence of Streptomyces viridosporus Strain T7A ATCC 39115, a Lignin-Degrading Actinomycete

    SciTech Connect

    Davis, Jennifer R.; Goodwin, Lynne A.; Teshima, Hazuki; Detter, J. Chris; Tapia, Roxanne; Han, Cliff; Huntemann, Marcel; Wei, Chia-Lin; Han, James; Chen, Amy; Kyrpides, Nikos C; Mavromatis, K; Szeto, Ernest; Markowitz, Victor; Ivanova, N; Mikhailova, Natalia; Ovchinnikova, Galina; Pagani, Ioanna; Pati, Amrita; Woyke, Tanja; Pitluck, Sam; Peters, Lin; Nolan, Matt; Land, Miriam L; Sello, Jason K.

    2013-01-01

    We announce the availability of the genome sequence of Streptomyces viridosporus strain T7A ATCC 39115, a plant biomass- degrading actinomycete. This bacterium is of special interest because of its capacity to degrade lignin, an underutilized compo- nent of plants in the context of bioenergy. It has a full complement of genes for plant biomass catabolism.

  5. Effect of Calcium in Assay Medium on D Value of Bacillus stearothermophilus ATCC 7953 Spores

    PubMed Central

    Sasaki, Koichi; Shintani, Hideharu; Itoh, Junpei; Kamogawa, Takuji; Kajihara, Yousei

    2000-01-01

    The D value of commercial biological indicator spore strips using Bacillus stearothermophilus ATCC 7953 was increased by higher calcium concentrations in assay media. The calcium concentration in assay media varied among the manufacturers. The calcium concentration in assay media is an important factor to consider to minimize the variation of D value. PMID:11097939

  6. Draft Genome Sequence of the Probiotic Strain Lactobacillus acidophilus ATCC 4356

    PubMed Central

    Palomino, Maria Mercedes; Allievi, Mariana C.; Fina Martin, Joaquina; Waehner, Pablo M.; Prado Acosta, Mariano; Sanchez Rivas, Carmen

    2015-01-01

    We present the 1,956,699-bp draft genome sequence of Lactobacillus acidophilus strain ATCC 4356. Comparative genomic analysis revealed 99.96% similarity with L. acidophilus NCFM NC_006814.3 and 99.97% with La-14 NC_021181.2 genomes. PMID:25593259

  7. Effect of calcium in assay medium on D value of Bacillus stearothermophilus ATCC 7953 spores.

    PubMed

    Sasaki, K; Shintani, H; Itoh, J; Kamogawa, T; Kajihara, Y

    2000-12-01

    The D value of commercial biological indicator spore strips using Bacillus stearothermophilus ATCC 7953 was increased by higher calcium concentrations in assay media. The calcium concentration in assay media varied among the manufacturers. The calcium concentration in assay media is an important factor to consider to minimize the variation of D value. PMID:11097939

  8. Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

    NASA Astrophysics Data System (ADS)

    He, Mengying; Wu, Ting; Pan, Siyi; Xu, Xiaoyun

    2014-06-01

    Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

  9. Draft Genome Sequence of the Probiotic Strain Lactobacillus acidophilus ATCC 4356.

    PubMed

    Palomino, Maria Mercedes; Allievi, Mariana C; Fina Martin, Joaquina; Waehner, Pablo M; Prado Acosta, Mariano; Sanchez Rivas, Carmen; Ruzal, Sandra M

    2015-01-01

    We present the 1,956,699-bp draft genome sequence of Lactobacillus acidophilus strain ATCC 4356. Comparative genomic analysis revealed 99.96% similarity with L. acidophilus NCFM NC_006814.3 and 99.97% with La-14 NC_021181.2 genomes. PMID:25593259

  10. Draft Genome Sequence of Streptomyces fradiae ATCC 19609, a Strain Highly Sensitive to Antibiotics.

    PubMed

    Bekker, Olga B; Klimina, Ksenia M; Vatlin, Aleksey A; Zakharevich, Natalia V; Kasianov, Artem S; Danilenko, Valery N

    2014-01-01

    We report here a sequence of the genome of the Streptomyces fradiae ATCC 19609 strain, initially isolated from the soil, which produces tylosin. S. fradiae is highly sensitive to different classes of antibiotics, compared to the sensitivities of other bacteria. We have identified 9 groups of genes directly or indirectly involved in the resistome formation. PMID:25477406

  11. Complete Genome Sequence and Methylome Analysis of Bacillus globigii ATCC 49760.

    PubMed

    Morgan, Richard D

    2016-01-01

    Bacillus subtilis (Ehrenburg) Cohn ATCC 49760, deposited as Bacillus globigii, is the source strain for the restriction enzymes BglI and BglII. Its complete sequence and full methylome were determined using single-molecule real-time (SMRT) sequencing. PMID:27231364

  12. Complete Genome Sequence and Methylome Analysis of Bacillus globigii ATCC 49760

    PubMed Central

    2016-01-01

    Bacillus subtilis (Ehrenburg) Cohn ATCC 49760, deposited as Bacillus globigii, is the source strain for the restriction enzymes BglI and BglII. Its complete sequence and full methylome were determined using single-molecule real-time (SMRT) sequencing. PMID:27231364

  13. Complete Genome Sequence of Thiostrepton-Producing Streptomyces laurentii ATCC 31255

    PubMed Central

    Fujino, Yasuhiro; Nagayoshi, Yuko; Ohshima, Toshihisa; Ogata, Seiya

    2016-01-01

    Streptomyces laurentii ATCC 31255 produces thiostrepton, a thiopeptide class antibiotic. Here, we report the complete genome sequence for this strain, which contains a total of 8,032,664 bp, 7,452 predicted coding sequences, and a G+C content of 72.3%. PMID:27257211

  14. Complete Genome Sequence of Brachyspira hyodysenteriae Type Strain B-78 (ATCC 27164).

    PubMed

    Mirajkar, Nandita S; Johnson, Timothy J; Gebhart, Connie J

    2016-01-01

    Reported herein is the complete genome sequence of the type strain B-78 (ATCC 27164) of Brachyspira hyodysenteriae, the etiological agent of swine dysentery. The 3.1-Mb genome consists of a 3.056-Mb chromosome and a 45-kb plasmid, with 2,617 protein-coding genes, 39 RNA genes, and 40 pseudogenes. PMID:27540064

  15. Characterization of a novel thiosulfate dehydrogenase from a marine acidophilic sulfur-oxidizing bacterium, Acidithiobacillus thiooxidans strain SH.

    PubMed

    Sharmin, Sultana; Yoshino, Eriko; Kanao, Tadayoshi; Kamimura, Kazuo

    2016-01-01

    A marine acidophilic sulfur-oxidizing bacterium, Acidithiobacillus thiooxidans strain SH, was isolated to develop a bioleaching process for NaCl-containing sulfide minerals. Because the sulfur moiety of sulfide minerals is metabolized to sulfate via thiosulfate as an intermediate, we purified and characterized the thiosulfate dehydrogenase (TSD) from strain SH. The enzyme had an apparent molecular mass of 44 kDa and was purified 71-fold from the solubilized membrane fraction. Tetrathionate was the product of the TSD-oxidized thiosulfate and ferricyanide or ubiquinone was the electron acceptor. Maximum enzyme activity was observed at pH 4.0, 40 °C, and 200 mM NaCl. To our knowledge, this is the first report of NaCl-stimulated TSD activity. TSD was structurally different from the previously reported thiosulfate-oxidizing enzymes. In addition, TSD activity was strongly inhibited by 2-heptyl-4-hydroxy-quinoline N-oxide, suggesting that the TSD is a novel thiosulfate:quinone reductase. PMID:26393925

  16. System-level understanding of the potential acid-tolerance components of Acidithiobacillus thiooxidans ZJJN-3 under extreme acid stress.

    PubMed

    Feng, Shoushuai; Yang, Hailin; Wang, Wu

    2015-09-01

    In previous study, two extremely acidophilic strains Acidithiobacillus thiooxidans ZJJN-3 (collection site: bioleaching leachate) and ZJJN-5 (collection site: bioleaching wastewater) were isolated from a typical industrial bio-heap in China. Here, we unraveled the potential acid-tolerance components of ZJJN-3 by comparing the physiological differences with ZJJN-5 under different acid stresses. The parameters used for comparison included intracellular pH (pHin), capsule morphology, fatty acid composition of cell membrane, transcription of key molecular chaperones, H(+)-ATPase activities and NAD(+)/NADH ratio. It was indicated that the acid-tolerance of A. thiooxidans ZJJN-3 was systematically regulated. Capsule first thickened and then shed off along with increased acid stress. Cell membrane maintained the intracellular stability by up-regulating the proportion of unsaturated fatty acid and cyclopropane fatty acids. Meanwhile, the transcription of key repair molecular chaperones (GrpE-DnaK-DnaJ) was up-regulated by 2.2-3.5 folds for ensuring the proper folding of peptide. Moreover, low pHin promoted ZJJN-3 to biosynthesize more H(+)-ATPase for pumping H(+) out of cells. Furthermore, the NAD(+)/NADH ratio increased due to the decreased H(+) concentration. Based on the above physiological analysis, the potential acid-tolerance components of A. thiooxidans ZJJN-3 were first proposed and it would be useful for better understanding how these extremophiles responded to the high acid stress. PMID:26264736

  17. Optimization of two-step bioleaching of spent petroleum refinery catalyst by Acidithiobacillus thiooxidans using response surface methodology.

    PubMed

    Srichandan, Haragobinda; Pathak, Ashish; Kim, Dong Jin; Lee, Seoung-Won

    2014-01-01

    A central composite design (CCD) combined with response surface methodology (RSM) was employed for maximizing bioleaching yields of metals (Al, Mo, Ni, and V) from as-received spent refinery catalyst using Acidithiobacillus thiooxidans. Three independent variables, namely initial pH, sulfur concentration, and pulp density were investigated. The pH was found to be the most influential parameter with leaching yields of metals varying inversely with pH. Analysis of variance (ANOVA) of the quadratic model indicated that the predicted values were in good agreement with experimental data. Under optimized conditions of 1.0% pulp density, 1.5% sulfur and pH 1.5, about 93% Ni, 44% Al, 34% Mo, and 94% V was leached from the spent refinery catalyst. Among all the metals, V had the highest maximum rate of leaching (Vmax) according to the Michaelis-Menten equation. The results of the study suggested that two-step bioleaching is efficient in leaching of metals from spent refinery catalyst. Moreover, the process can be conducted with as received spent refinery catalyst, thus making the process cost effective for large-scale applications. PMID:25320861

  18. Construction of conjugative gene transfer system between E. coli and moderately thermophilic, extremely acidophilic Acidithiobacillus caldus MTH-04.

    PubMed

    Liu, Xiangmei; Lin, Jianqun; Zhang, Zheng; Bian, Jiang; Zhao, Qing; Liu, Ying; Lin, Jianqiang; Yan, Wangming

    2007-01-01

    A genetic transfer system for introducing foreign genes to biomining microorganisms is urgently needed. Thus, a conjugative gene transfer system was investigated for a moderately thermophilic, extremely acidophilic biomining bacterium, Acidithiobacillus caldus MTH-04. The broad-host-range IncP plasmids RP4 and R68.45 were transferred directly into A. caldus MTH-04 from Escherichia coli by conjugation at relatively high frequencies. Additionally the broad-host-range IncQ plasmids pJRD215, pVLT33, and pVLT35 were also transferred into A. caldus MTH-04 with the help of plasmid RP4 or strains with plasmid RP4 integrated into their chromosome, such as E. coli SM10. The Km(r) and Sm(r) selectable markers from these plasmids were successfully expressed in A. caldus MTH-04. Futhermore, the IncP and IncQ plasmids were transferred back into E. coli cells from A. caldus MTH-04, thereby confirming the initial transfer of these plasmids from E. coli to A. caldus MTH-04. All the IncP and IncQ plasmids studied were stable in A. caldus MTH-04. Consequently, this development of a conjugational system for A. caldus MTH-04 will greatly facilitate its genetic study. PMID:18051368

  19. Hydrogen sulfide oxidation in novel Horizontal-Flow Biofilm Reactors dominated by an Acidithiobacillus and a Thiobacillus species.

    PubMed

    Gerrity, S; Kennelly, C; Clifford, E; Collins, G

    2016-09-01

    Hydrogen Sulfide (H2S) is an odourous, highly toxic gas commonly encountered in various commercial and municipal sectors. Three novel, laboratory-scale, Horizontal-Flow Biofilm Reactors (HFBRs) were tested for the removal of H2S gas from air streams over a 178-day trial at 10°C. Removal rates of up to 15.1 g [H2S] m(-3) h(-1) were achieved, demonstrating the HFBRs as a feasible technology for the treatment of H2S-contaminated airstreams at low temperatures. Bio-oxidation of H2S in the reactors led to the production of H(+) and sulfate (SO(2-)4) ions, resulting in the acidification of the liquid phase. Reduced removal efficiency was observed at loading rates of 15.1 g [H2S] m(-3) h(-1). NaHCO3 addition to the liquid nutrient feed (synthetic wastewater (SWW)) resulted in improved H2S removal. Bacterial diversity, which was investigated by sequencing and fingerprinting 16S rRNA genes, was low, likely due to the harsh conditions prevailing in the systems. The HFBRs were dominated by two species from the genus Acidithiobacillus and Thiobacillus. Nonetheless, there were significant differences in microbial community structure between distinct HFBR zones due to the influence of alkalinity, pH and SO4 concentrations. Despite the low temperature, this study indicates HFBRs have an excellent potential to biologically treat H2S-contaminated airstreams. PMID:26829048

  20. Isolation and characterization of flagellar filaments from Bacillus cereus ATCC 14579.

    PubMed

    Tagawa, Yuichi

    2014-12-01

    Isolated flagellar filaments from the type strain of Bacillus cereus, ATCC 14579, were shown to consist of 34, 32 and 31 kDa proteins in similar proportions as judged by band intensities on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The N-terminal amino acid sequences of these three proteins of strain ATCC 14579 were identical with the deduced sequences of three flagellin genes BC1657, BC1658 and BC1659 in the whole genome sequence. Strain ATCC 14579 was classified into serotype T2 by a flagellar serotyping scheme for B. cereus strains that are untypeable into known flagellar serotypes H1 to H23. Flagellar filaments from a reference strain of serotype T2 contained two protein bands at 34 and 32 kDa, but a single protein band at 39 kDa was detected in flagellar filaments of a reference strain of serotype H1. Two murine monoclonal antibodies, 1A5 and 2A5, which recognize both the 34 and 32 kDa flagellins and a single flagellin of 32 kDa, respectively, were specifically reactive with B. cereus strains ATCC 14579 and serotype T2 in whole-cell ELISA and bacterial motility inhibition tests. In immunoelectron microscopy with monoclonal antibodies 1A5 and 2A5, colloidal gold spheres were shown to localize almost evenly over the entire part of flagellar filaments. Since strain ATCC 14579, and presumably strain serotype T2, are unusual among B. cereus strains in possessing multiple genes that encode flagellin subunits, a possible unique mechanism may contribute to assembly of multiple flagellin subunits into the filament over its entire length. PMID:25227778

  1. Growth of Lactobacillus paracasei ATCC 334 in a cheese model system: a biochemical approach.

    PubMed

    Budinich, M F; Perez-Díaz, I; Cai, H; Rankin, S A; Broadbent, J R; Steele, J L

    2011-11-01

    Growth of Lactobacillus paracasei ATCC 334, in a cheese-ripening model system based upon a medium prepared from ripening Cheddar cheese extract (CCE) was evaluated. Lactobacillus paracasei ATCC 334 grows in CCE made from cheese ripened for 2 (2mCCE), 6 (6mCCE), and 8 (8mCCE) mo, to final cell densities of 5.9×10(8), 1.2×10(8), and 2.1×10(7)cfu/mL, respectively. Biochemical analysis and mass balance equations were used to determine substrate consumption patterns and products formed in 2mCCE. The products formed included formate, acetate, and D-lactate. These data allowed us to identify the pathways likely used and to initiate metabolic flux analysis. The production of volatiles during growth of Lb. paracasei ATCC 334 in 8mCCE was monitored to evaluate the metabolic pathways utilized by Lb. paracasei during the later stages of ripening Cheddar cheese. The 2 volatiles detected at high levels were ethanol and acetate. The remaining detected volatiles are present in significantly lower amounts and likely result from amino acid, pyruvate, and acetyl-coenzyme A metabolism. Carbon balance of galactose, lactose, citrate, and phosphoserine/phosphoserine-containing peptides in terms of D-lactate, acetate, and formate are in agreement with the amounts of substrates observed in 2mCCE; however, this was not the case for 6mCCE and 8mCCE, suggesting that additional energy sources are utilized during growth of Lb. paracasei ATCC 334 in these CCE. This study provides valuable information on the biochemistry and physiology of Lb. paracasei ATCC 334 in ripening cheese. PMID:22032349

  2. Processing of cellulosic material by a cellulase-containing cell-free fermentate produced from cellulase-producing bacteria, ATCC 55702

    DOEpatents

    Dees, H. Craig

    1998-01-01

    Bacteria which produce large amounts of a cellulase-containing cell-free fermentate, have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase degrading bacterium ATCC 55702, which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic materials.

  3. Processing of cellulosic material by a cellulase-containing cell-free fermentate produced from cellulase-producing bacteria, ATCC 55702

    DOEpatents

    Dees, H.C.

    1998-08-04

    Bacteria which produce large amounts of a cellulase-containing cell-free fermentate, have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase degrading bacterium ATCC 55702, which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic materials. 5 figs.

  4. Lactobacillus acidophilus ATCC 4356 prevents atherosclerosis via inhibition of intestinal cholesterol absorption in apolipoprotein E-knockout mice.

    PubMed

    Huang, Ying; Wang, Jinfeng; Quan, Guihua; Wang, Xiaojun; Yang, Longfei; Zhong, Lili

    2014-12-01

    The objective of this study was to investigate the effect of Lactobacillus acidophilus ATCC 4356 on the development of atherosclerosis in apolipoprotein E-knockout (ApoE(-/-)) mice. Eight-week-old ApoE(-/-) mice were fed a Western diet with or without L. acidophilus ATCC 4356 daily for 16 weeks. L. acidophilus ATCC 4356 protected ApoE(-/-) mice from atherosclerosis by reducing their plasma cholesterol levels from 923 ± 44 to 581 ± 18 mg/dl, likely via a marked decrease in cholesterol absorption caused by modulation of Niemann-Pick C1-like 1 (NPC1L1). In addition, suppression of cholesterol absorption induced reverse cholesterol transport (RCT) in macrophages through the peroxisome proliferator-activated receptor/liver X receptor (PPAR/LXR) pathway. Fecal lactobacillus and bifidobacterium counts were significantly (P < 0.05) higher in the L. acidophilus ATCC 4356 treatment groups than in the control groups. Furthermore, L. acidophilus ATCC 4356 was detected in the rat small intestine, colon, and feces during the feeding trial. The bacterial levels remained high even after the administration of lactic acid bacteria had been stopped for 2 weeks. These results suggest that administration of L. acidophilus ATCC 4356 can protect against atherosclerosis through the inhibition of intestinal cholesterol absorption. Therefore, L. acidophilus ATCC 4356 may be a potential therapeutic material for preventing the progression of atherosclerosis. PMID:25261526

  5. Lactobacillus acidophilus ATCC 4356 Prevents Atherosclerosis via Inhibition of Intestinal Cholesterol Absorption in Apolipoprotein E-Knockout Mice

    PubMed Central

    Wang, Jinfeng; Quan, Guihua; Wang, Xiaojun; Yang, Longfei; Zhong, Lili

    2014-01-01

    The objective of this study was to investigate the effect of Lactobacillus acidophilus ATCC 4356 on the development of atherosclerosis in apolipoprotein E-knockout (ApoE−/−) mice. Eight-week-old ApoE−/− mice were fed a Western diet with or without L. acidophilus ATCC 4356 daily for 16 weeks. L. acidophilus ATCC 4356 protected ApoE−/− mice from atherosclerosis by reducing their plasma cholesterol levels from 923 ± 44 to 581 ± 18 mg/dl, likely via a marked decrease in cholesterol absorption caused by modulation of Niemann-Pick C1-like 1 (NPC1L1). In addition, suppression of cholesterol absorption induced reverse cholesterol transport (RCT) in macrophages through the peroxisome proliferator-activated receptor/liver X receptor (PPAR/LXR) pathway. Fecal lactobacillus and bifidobacterium counts were significantly (P < 0.05) higher in the L. acidophilus ATCC 4356 treatment groups than in the control groups. Furthermore, L. acidophilus ATCC 4356 was detected in the rat small intestine, colon, and feces during the feeding trial. The bacterial levels remained high even after the administration of lactic acid bacteria had been stopped for 2 weeks. These results suggest that administration of L. acidophilus ATCC 4356 can protect against atherosclerosis through the inhibition of intestinal cholesterol absorption. Therefore, L. acidophilus ATCC 4356 may be a potential therapeutic material for preventing the progression of atherosclerosis. PMID:25261526

  6. Stability of free and encapsulated Lactobacillus acidophilus ATCC 4356 in yogurt and in an artificial human gastric digestion system.

    PubMed

    Ortakci, F; Sert, S

    2012-12-01

    The objective of this study was to determine the effect of encapsulation on survival of probiotic Lactobacillus acidophilus ATCC 4356 (ATCC 4356) in yogurt and during artificial gastric digestion. Strain ATCC 4356 was added to yogurt either encapsulated in calcium alginate or in free form (unencapsulated) at levels of 8.26 and 9.47 log cfu/g, respectively, and the influence of alginate capsules (1.5 to 2.5mm) on the sensorial characteristics of yogurts was investigated. The ATCC 4356 strain was introduced into an artificial gastric solution consisting of 0.08 N HCl (pH 1.5) containing 0.2% NaCl or into artificial bile juice consisting of 1.2% bile salts in de Man, Rogosa, and Sharpe broth to determine the stability of the probiotic bacteria. When incubated for 2h in artificial gastric juice, the free ATCC 4356 did not survive (reduction of >7 log cfu/g). We observed, however, greater survival of encapsulated ATCC 4356, with a reduction of only 3 log cfu/g. Incubation in artificial bile juice (6 h) did not significantly affect the viability of free or encapsulated ATCC 4356. Moreover, statistically significant reductions (~1 log cfu/g) of both free and encapsulated ATCC 4356 were observed during 4-wk refrigerated storage of yogurts. The addition of probiotic cultures in free or alginate-encapsulated form did not significantly affect appearance/color or flavor/odor of the yogurts. However, significant deficiencies were found in body/texture of yogurts containing encapsulated ATCC 4356. We concluded that incorporation of free and encapsulated probiotic bacteria did not substantially change the overall sensory properties of yogurts, and encapsulation in alginate using the extrusion method greatly enhanced the survival of probiotic bacteria against an artificial human gastric digestive system. PMID:23021757

  7. Purification and some properties of sulfur reductase from the iron-oxidizing bacterium Thiobacillus ferrooxidans NASF-1.

    PubMed

    Ng, K Y; Sawada, R; Inoue, S; Kamimura, K; Sugio, T

    2000-01-01

    Thiobacillus ferrooxidans strain NASF-1 grown aerobically in an Fe2+ (3%)-medium produces hydrogen sulfide (H2S) from elemental sulfur under anaerobic conditions with argon gas at pH 7.5. Sulfur reductase, which catalyzes the reduction of elemental sulfur (S0) with NAD(P)H as an electron donor to produce hydrogen sulfide (H2S) under anaerobic conditions, was purified 69-fold after 35-65% ammonium sulfate precipitation and Q-Sepharose FF, Phenyl-Toyopearl 650 ML, and Blue Sepharose FF column chromatography, with a specific activity of 57.6 U (mg protein)(-1). The purified enzyme was quite labile under aerobic conditions, but comparatively stable in the presence of sodium hydrosulfite and under anaerobic conditions, especially under hydrogen gas conditions. The purified enzyme showed both sulfur reductase and hydrogenase activities. Both activities had an optimum pH of 9.0. Sulfur reductase has an apparent molecular weight of 120,000 Da, and is composed of three different subunits (M(r) 54,000 Da (alpha), 36,000 Da (beta), and 35,000 Da (gamma)), as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This is the first report on the purification of sulfur reductase from a mesophilic and obligate chemolithotrophic iron-oxidizing bacterium. PMID:16232842

  8. Solubilization of Minerals by Bacteria: Electrophoretic Mobility of Thiobacillus ferrooxidans in the Presence of Iron, Pyrite, and Sulfur

    PubMed Central

    Blake, Robert C.; Shute, Elizabeth A.; Howard, Gary T.

    1994-01-01

    Thiobacillus ferroxidans is an obligate acidophile that respires aerobically on pyrite, elemental sulfur, or soluble ferrous ions. The electrophoretic mobility of the bacterium was determined by laser Doppler velocimetry under physiological conditions. When grown on pyrite or ferrous ions, washed cells were negatively charged at pH 2.0. The density of the negative charge depended on whether the conjugate base was sulfate, perchlorate, chloride, or nitrate. The addition of ferric ions shifted the net charge on the surface asymptotically to a positive value. When grown on elemental sulfur, washed cells were close to their isoelectric point at pH 2.0. Both pyrite and colloidal sulfur were negatively charged under the same conditions. The electrical double layer around the bacterial cells under physiological conditions exerted minimal electrostatic repulsion in possible interactions between the cell and either of its charged insoluble substrates. When Thiobacillus ferrooxidans was mixed with either pyrite or colloidal sulfur at pH 2.0, the mobility spectra of the free components disappeared with time to be replaced with a new colloidal particle whose electrophoretic properties were intermediate between those of the starting components. This new particle had the charge and size properties anticipated for a complex between the bacterium and its insoluble substrates. The utility of such measurements for the study of the interactions of chemolithotrophic bacteria with their insoluble substrates is discussed. Images PMID:16349387

  9. Constitutive synthesis of a transport function encoded by the Thiobacillus ferrooxidans merC gene cloned in Escherichia coli

    SciTech Connect

    Kusano, Tomonobu Akita Prefectural College of Agriculture ); Ji, Guangyong; Silver, S. ); Inoue, Chihiro )

    1990-05-01

    Mercuric reductase activity determined by the Thiobacillus ferrooxidans merA gene (cloned and expressed constitutively in Escherichia coli) was measured by volatilization of {sup 203}Hg{sup 2+}. (The absence of a merR regulatory gene in the cloned Thiobacillus mer determinant provides a basis for the constitutive synthesis of this system.) In the absence of the Thiobacillus merC transport gene, the mercury volatilization activity was cryptic and was not seen with whole cells but only with sonication-disrupted cells. The Thiobacillus merC transport function was compared with transport via the merT-merP system of plasmid pDU1358. Both systems, cloned and expressed in E. coli, governed enhanced uptake of {sup 203}Hg{sup 2+} in a temperature- and concentration-dependent fashion. Uptake via MerT-MerP was greater and conferred greater hypersensitivity to Hg{sup 2+} than did uptake with MerC. Mercury uptake was inhibited by N-ethylmaleimide but not by EDTA. Ag{sup +} salts inhibited mercury uptake by the MerT-MerP system but did not inhibit uptake via MerC. Radioactive mercury accumulated by the MerT-MerP and by the MerC systems was exchangeable with nonradioactive Hg{sup 2+}.

  10. Significant differences between Lactobacillus casei subsp. casei ATCC 393T and a commonly used plasmid-cured derivative revealed by a polyphasic study.

    PubMed

    Acedo-Félix, Evelia; Pérez-Martínez, Gaspar

    2003-01-01

    Many studies on Lactobacillus casei subsp. casei (L. casei) have been carried out using strain ATCC 393 (pLZ15-). Four strains of L. casei ATCC 393T and three of ATCC 393 (pLZ15-) were compared using phenotypic methods and many of the available genotyping techniques. These tests showed that strains of ATCC 393T obtained from independent public type-culture collections were significantly different from the plasmid-free (pLZ15-) strains of ATCC 393T. These findings were confirmed by sequencing the first 580 nt (domain I) of the 16S and 23S rDNAs of the strains. Complete sequencing of the 16S rDNA of one representative strain from each group revealed that strain ATCC 393T from culture collections was 99% similar to Lactobacillus zeae ATCC 15820T and that the strain so far considered as L. casei ATCC 393 (pLZ15-) was, in turn, 100% similar to L. casei ATCC 334 and Lactobacillus paracasei subsp. paracasei ATCC 4022. All data obtained in this work indicate that the ancestral strain of ATCC 393 (pLZ15-) might never have been the strain that is now available from culture collections. PMID:12656154

  11. The Effect of Oxygen Supply on the Dual Growth Kinetics of Acidithiobacillus thiooxidans under Acidic Conditions for Biogas Desulfurization

    PubMed Central

    Namgung, Hyeong-Kyu; Song, JiHyeon

    2015-01-01

    In this study, to simulate a biogas desulfurization process, a modified Monod-Gompertz kinetic model incorporating a dissolved oxygen (DO) effect was proposed for a sulfur-oxidizing bacterial (SOB) strain, Acidithiobacillus thiooxidans, under extremely acidic conditions of pH 2. The kinetic model was calibrated and validated using experimental data obtained from a bubble-column bioreactor. The SOB strain was effective for H2S degradation, but the H2S removal efficiency dropped rapidly at DO concentrations less than 2.0 mg/L. A low H2S loading was effectively treated with oxygen supplied in a range of 2%–6%, but a H2S guideline of 10 ppm could not be met, even with an oxygen supply greater than 6%, when the H2S loading was high at a short gas retention time of 1 min and a H2S inlet concentration of 5000 ppm. The oxygen supply should be increased in the aerobic desulfurization to meet the H2S guideline; however, the excess oxygen above the optimum was not effective because of the decline in oxygen efficiency. The model estimation indicated that the maximum H2S removal rate was approximately 400 ppm/%-O2 at the influent oxygen concentration of 4.9% under the given condition. The kinetic model with a low DO threshold for the interacting substrates was a useful tool to simulate the effect of the oxygen supply on the H2S removal and to determine the optimal oxygen concentration. PMID:25633028

  12. Construction and application of an expression vector from the new plasmid pLAtc1 of Acidithiobacillus caldus.

    PubMed

    Zhang, Ming-Jiang; Jiang, Cheng-Ying; You, Xiao-Yan; Liu, Shuang-Jiang

    2014-05-01

    In this study, a recently sequenced 9.8-kb plasmid, pLAtc1, from Acidithiobacillus caldus strain SM-1 was characterized and developed into an expression vector. The pLAtc1 backbone carried an oriV, three rep genes, five mob genes, a Nic site, and an addiction system. Multilocus sequence analysis indicated that pLAtc1 was phylogenetically more related to the IncQ-like broad host range plasmids than to other IncQ plasmids. pLAtc1 was able to replicate and reside in Gram-negative Escherichia coli, Comamonas testosteroni, but not in Gram-positive Corynebacterium glutamicum. pLAtc1 was mobilized via conjugation into E. coli BL21 and A. caldus SM-1 from E. coli S17-1. Quantitative PCR revealed seven and four copies of plasmid in A. caldus and E. coli cells, respectively. The expression vector pLAtcE was constructed from pLAtc1 by introducing a regulatable promoter (P tetH ), a transcriptional terminator, a multiple cloning site, a kanamycin resistance gene, and a streptomycin resistance gene. The functionality of pLAtcE was demonstrated by expressing a gene encoding enhanced green fluorescence protein in E. coli and in A. caldus. pLAtcE was used to express α-ketoglutarate dehydrogenase (sucAB) and succinate dehydrogenase (sdhA) genes in A. caldus. The newly engineered strain that harbored sucAB and sdhA on a plasmid pLAtcE-sucA-sucB-sdhA grew better than the parent strain SM-1/pLAtcE in tetrathionate and glucose-supplemented medium and produced more acidity and resulted in a more oxidative environment. This study created a useful molecular tool for genetic manipulation of the thermoacidophilic and autotrophic A. caldus. PMID:24445921

  13. Chemical and surface analysis during evolution of arsenopyrite oxidation by Acidithiobacillus thiooxidans in the presence and absence of supplementary arsenic.

    PubMed

    Ramírez-Aldaba, Hugo; Valles, O Paola; Vazquez-Arenas, Jorge; Rojas-Contreras, J Antonio; Valdez-Pérez, Donato; Ruiz-Baca, Estela; Meraz-Rodríguez, Mónica; Sosa-Rodríguez, Fabiola S; Rodríguez, Ángel G; Lara, René H

    2016-10-01

    Bioleaching of arsenopyrite presents a great interest due to recovery of valuable metals and environmental issues. The current study aims to evaluate the arsenopyrite oxidation by Acidithiobacillus thiooxidans during 240h at different time intervals, in the presence and absence of supplementary arsenic. Chemical and electrochemical characterizations are carried out using Raman, AFM, SEM-EDS, Cyclic Voltammetry, EIS, electrophoretic and adhesion forces to comprehensively assess the surface behavior and biooxidation mechanism of this mineral. These analyses evidence the formation of pyrite-like secondary phase on abiotic control surfaces, which contrast with the formation of pyrite (FeS2)-like, orpiment (As2S3)-like and elementary sulfur and polysulfide (Sn(2-)/S(0)) phases found on biooxidized surfaces. Voltammetric results indicate a significant alteration of arsenopyrite due to (bio)oxidation. Resistive processes determined with EIS are associated with chemical and electrochemical reactions mediated by (bio)oxidation, resulting in the transformation of arsenopyrite surface and biofilm direct attachment. Charge transfer resistance is increased when (bio)oxidation is performed in the presence of supplementary arsenic, in comparison with lowered abiotic control resistances obtained in its absence; reinforcing the idea that more stable surface products are generated when As(V) is in the system. Biofilm structure is mainly comprised of micro-colonies, progressively enclosed in secondary compounds. A more compact biofilm structure with enhanced formation of secondary compounds is identified in the presence of supplementary arsenic, whereby variable arsenopyrite reactivity is linked and attributed to these secondary compounds, including Sn(2-)/S(0), pyrite-like and orpiment-like phases. PMID:27312277

  14. The effect of oxygen supply on the dual growth kinetics of Acidithiobacillus thiooxidans under acidic conditions for biogas desulfurization.

    PubMed

    Namgung, Hyeong-Kyu; Song, JiHyeon

    2015-02-01

    In this study, to simulate a biogas desulfurization process, a modified Monod-Gompertz kinetic model incorporating a dissolved oxygen (DO) effect was proposed for a sulfur-oxidizing bacterial (SOB) strain, Acidithiobacillus thiooxidans, under extremely acidic conditions of pH 2. The kinetic model was calibrated and validated using experimental data obtained from a bubble-column bioreactor. The SOB strain was effective for H2S degradation, but the H2S removal efficiency dropped rapidly at DO concentrations less than 2.0 mg/L. A low H2S loading was effectively treated with oxygen supplied in a range of 2%-6%, but a H2S guideline of 10 ppm could not be met, even with an oxygen supply greater than 6%, when the H2S loading was high at a short gas retention time of 1 min and a H2S inlet concentration of 5000 ppm. The oxygen supply should be increased in the aerobic desulfurization to meet the H2S guideline; however, the excess oxygen above the optimum was not effective because of the decline in oxygen efficiency. The model estimation indicated that the maximum H2S removal rate was approximately 400 ppm/%-O2 at the influent oxygen concentration of 4.9% under the given condition. The kinetic model with a low DO threshold for the interacting substrates was a useful tool to simulate the effect of the oxygen supply on the H2S removal and to determine the optimal oxygen concentration. PMID:25633028

  15. Insights on the structure and stability of Licanantase: a trimeric acid-stable coiled-coil lipoprotein from Acidithiobacillus thiooxidans

    PubMed Central

    Abarca, Fernando; Gutierrez-Maldonado, Sebastian E.; Parada, Pilar; Martinez, Patricio; Maass, Alejandro

    2014-01-01

    Licanantase (Lic) is the major component of the secretome of Acidithiobacillus thiooxidans when grown in elemental sulphur. When used as an additive, Lic improves copper recovery from bioleaching processes. However, this recovery enhancement is not fully understood. In this context, our aim is to predict the 3D structure of Lic, to shed light on its structure-function relationships. Bioinformatics analyses on the amino acid sequence of Lic showed a great similarity with Lpp, an Escherichia coli Lipoprotein that can form stable trimers in solution. Lic and Lpp share the secretion motif, intracellular processing and alpha helix structure, as well as the distribution of hydrophobic residues in heptads forming a hydrophobic core, typical of coiled-coil structures. Cross-linking experiments showed the presence of Lic trimers, supporting our predictions. Taking the in vitro and in silico evidence as a whole, we propose that the most probable structure for Lic is a trimeric coiled-coil. According to this prediction, a suitable model for Lic was produced using the de novo algorithm “Rosetta Fold-and-Dock”. To assess the structural stability of our model, Molecular Dynamics (MD) and Replica Exchange MD simulations were performed using the structure of Lpp and a 14-alanine Lpp mutant as controls, at both acidic and neutral pH. Our results suggest that Lic was the most stable structure among the studied proteins in both pH conditions. This increased stability can be explained by a higher number of both intermonomer hydrophobic contacts and hydrogen bonds, key elements for the stability of Lic’s secondary and tertiary structure. PMID:25165619

  16. Effect of nitrogen source on curdlan production by Alcaligenes faecalis ATCC 31749.

    PubMed

    Jiang, Longfa

    2013-01-01

    This study aims to investigate the effect of nitrogen source on curdlan production by Alcaligenes faecalis ATCC 31749. Curdlan production fell when excess nitrogen source was present, while biomass accumulation increased as the level of nitrogen source raised. Curdlan production and biomass accumulation were greater with urea compared with those with other nitrogen sources. The highest production of curdlan and biomass accumulation by A. faecalis ATCC 31749 was 28.16 g L(-1) and 9.58 g L(-1), respectively, with urea, whereas those with NH(4)Cl were 15.17 g L(-1) and 6.25 g L(-1), respectively. The optimum fermentation time for curdlan production was also affected by the nitrogen source in the medium. PMID:23085490

  17. Effects of phosphoenolpyruvate carboxylase desensitization on glutamic acid production in Corynebacterium glutamicum ATCC 13032.

    PubMed

    Wada, Masaru; Sawada, Kazunori; Ogura, Kotaro; Shimono, Yuta; Hagiwara, Takuya; Sugimoto, Masakazu; Onuki, Akiko; Yokota, Atsushi

    2016-02-01

    Phosphoenolpyruvate carboxylase (PEPC) in Corynebacterium glutamicum ATCC13032, a glutamic-acid producing actinobacterium, is subject to feedback inhibition by metabolic intermediates such as aspartic acid and 2-oxoglutaric acid, which implies the importance of PEPC in replenishing oxaloacetic acid into the TCA cycle. Here, we investigated the effects of feedback-insensitive PEPC on glutamic acid production. A single amino-acid substitution in PEPC, D299N, was found to relieve the feedback control by aspartic acid, but not by 2-oxoglutaric acid. A simple mutant, strain R1, having the D299N substitution in PEPC was constructed from ATCC 13032 using the double-crossover chromosome replacement technique. Strain R1 produced glutamic acid at a concentration of 31.0 g/L from 100 g/L glucose in a jar fermentor culture under biotin-limited conditions, which was significantly higher than that of the parent, 26.0 g/L (1.19-fold), indicative of the positive effect of desensitized PEPC on glutamic acid production. Another mutant, strain DR1, having both desensitized PEPC and PYK-gene deleted mutations, was constructed in a similar manner using strain D1 with a PYK-gene deleted mutation as the parent. This mutation had been shown to enhance glutamic acid production in our previous study. Although marginal, strain D1 produced higher glutamic acid, 28.8 g/L, than ATCC13032 (1.11-fold). In contrast, glutamic acid production by strain DR-1 was elevated up to 36.9 g/L, which was 1.42-fold higher than ATCC13032 and significantly higher than the other three strains. The results showed a synergistic effect of these two mutations on glutamic acid production in C. glutamicum. PMID:26168906

  18. Genome sequence of the methanotrophic Alphaproteobacterium, Methylocystis sp. Rockwell (ATCC 49242)

    SciTech Connect

    Stein, Lisa Y.; Bringel, Francoise O.; DiSpiritto, Alan A.; Han, Sukkyun; Jetten, MSM; Kalyuzhnaya, Marina G.; Kits, K. Dimitri; Klotz, Martin G; Op den Camp, HJM; Semrau, Jeremy D.; Vuilleumier, Stephane; Bruce, David; Cheng, Jan-Fang; Copeland, A; Davenport, Karen W.; Goodwin, Lynne A.; Han, Cliff; Hauser, Loren John; Lajus, Aurelie; Lapidus, Alla L.; Lucas, Susan; Medigue, Claudine

    2011-01-01

    Methylocystis sp. strain Rockwell (ATCC 49242) is an aerobic methane-oxidizing Alphaproteobacterium isolated from an aquifer in southern California. Unlike most methanotrophs in the Methylocystaceae family, this strain has a single pmo operon encoding particulate methane monooxygenase and no evidence of the genes encoding soluble methane monooxygenase. This is the first reported genome sequence of a member of the Methylocystis species of the Methylocystaceae family in the order Rhizobiales.

  19. Complete Genome Assembly of Streptococcus pyogenes ATCC 19615, a Group A β-Hemolytic Reference Strain.

    PubMed

    Minogue, T D; Daligault, H A; Davenport, K W; Bishop-Lilly, K A; Broomall, S M; Bruce, D C; Chain, P S; Chertkov, O; Coyne, S R; Freitas, T; Frey, K G; Gibbons, H S; Jaissle, J; Redden, C L; Rosenzweig, C N; Xu, Y; Johnson, S L

    2014-01-01

    We present the complete genome assembly of Streptococcus pyogenes ATCC 19615 (Rosenbach) as submitted to GenBank under accession number CP008926. This group A nonmotile β-hemolytic clinical isolate is used for quality control in a variety of commercially available tests. The assembled genome is 1.84 Mb (38.5% G+C content) and contains 1,788 coding regions. PMID:25258274

  20. Complete Genome Assembly of Streptococcus pyogenes ATCC 19615, a Group A β-Hemolytic Reference Strain

    PubMed Central

    Minogue, T. D.; Daligault, H. A.; Davenport, K. W.; Bishop-Lilly, K. A.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Chertkov, O.; Coyne, S. R.; Freitas, T.; Frey, K. G.; Gibbons, H. S.; Jaissle, J.; Redden, C. L.; Rosenzweig, C. N.; Xu, Y.

    2014-01-01

    We present the complete genome assembly of Streptococcus pyogenes ATCC 19615 (Rosenbach) as submitted to GenBank under accession number CP008926. This group A nonmotile β-hemolytic clinical isolate is used for quality control in a variety of commercially available tests. The assembled genome is 1.84 Mb (38.5% G+C content) and contains 1,788 coding regions. PMID:25258274

  1. Efficacy of oral Bifidobacterium bifidum ATCC 29521 on microflora and antioxidant in mice.

    PubMed

    Wang, Bao-Gui; Xu, Hai-Bo; Xu, Feng; Zeng, Zhe-Ling; Wei, Hua

    2016-03-01

    This study aimed to examine whether Bifidobacterium bifidum ATCC 29521, a species of colonic microflora in humans, is involved in the intestinal tract of mice. This study was also conducted to determine the antioxidant activity of this species by evaluating different microbial populations and reactive oxygen species isolated from feces and intestinal contents for 28 days of oral administration. Microbial diversities were assessed through bacterial culture techniques, PCR-DGGE, and real-time PCR. This study showed that the intake of B. bifidum ATCC 29521 significantly (p < 0.05) improved the ecosystem of the intestinal tract of BALB/c mice by increasing the amount of probiotics (Lactobacillus intestinalis and Lactobacillus crispatus) and by reducing unwanted bacterial populations (Enterobacter, Escherichia coli). Antioxidative activities of incubated cell-free extracts were evaluated through various assays, including the scavenging ability of DPPH radical (64.5% and 67.54% (p < 0.05), respectively, at 21 days in nutrients and 28 days in MRS broth), superoxide anion, and hydroxyl radical (85% and 61.5% (p < 0.05), respectively, at intestinal contents in nutrients and 21 days in MRS broth). Total reducing power (231.5 μmol/L (p < 0.05), 14 days in MRS broth) and mRNA level of genes related to oxidative stress were also determined. Results indicated that B. bifidum ATCC 29521 elicits a beneficial effect on murine gut microbiota and antioxidant activities compared with the control samples. This species can be considered as a potential bioresource antioxidant to promote health. Bifidobacterium bifidum ATCC 29521 may also be used as a promising material in microbiological and food applications. PMID:26863255

  2. Complete Genome Sequence of Pseudomonas syringae pv. lapsa Strain ATCC 10859, Isolated from Infected Wheat

    PubMed Central

    Kong, Jun; Jiang, Hongshan; Li, Baiyun; Zhao, Wenjun

    2016-01-01

    Pseudomonas syringae pv. lapsa is a pathovar of Pseudomonas syringae that can infect wheat. The complete genome of P. syringae pv. lapsa strain ATCC 10859 contains a 5,918,899-bp circular chromosome with 4,973 coding sequences, 16 rRNAs, 69 tRNAs, and an average GC content of 59.13%. The analysis of this genome revealed several gene clusters that are related to pathogenesis and virulence. PMID:26941133

  3. Cloning, characterization, and production of three α-l-fucosidases from Clostridium perfringens ATCC 13124.

    PubMed

    Fan, Shuquan; Zhang, Huaqin; Chen, Xiaodi; Lu, Lili; Xu, Li; Xiao, Min

    2016-04-01

    α-l-Fucosidases are key enzymes for the degradation of intestinal glycans by gut microbes. In this work, three putative α-l-fucosidases (Afc1, Afc2, and Afc3) genes from Clostridium perfringens ATCC 13124 were cloned and expressed in Escherichia coli. Afc1 had the α-l-fucosidase domain of glycoside hydrolase (GH) 29 family but showed no enzyme activity toward all the substrates examined. The putative acid/base residue of Afc1, Ser205, was replaced by a glutamic acid which is conserved in GH29-B α-l-fucosidases. However, the mutant Afc1-S205E still failed to show enzyme activity. Afc2 and Afc3 were determined to be 1,3-1,4-α-l-fucosidase of GH29-B subfamily and 1,2-α-l-fucosidase of GH95 family, respectively, and both of them could release fucose from porcine gastric mucin (PGM). When C. perfringens ATCC 13124 grew with the presence of PGM, the transcription of afc1 decreased slightly, while those of afc2 and afc3 increased to 2.2-fold and 1.4-fold, respectively, and the enzyme activities of Afc2 and Afc3 in the culture increased to 2.2-fold and 2.6-fold, respectively. These results suggest that Afc2 and Afc3 are involved in the degradation of intestinal fucosyl glycans by C. perfringens ATCC 13124. PMID:26663202

  4. Genome-scale reconstruction of metabolic networks of Lactobacillus casei ATCC 334 and 12A.

    PubMed

    Vinay-Lara, Elena; Hamilton, Joshua J; Stahl, Buffy; Broadbent, Jeff R; Reed, Jennifer L; Steele, James L

    2014-01-01

    Lactobacillus casei strains are widely used in industry and the utility of this organism in these industrial applications is strain dependent. Hence, tools capable of predicting strain specific phenotypes would have utility in the selection of strains for specific industrial processes. Genome-scale metabolic models can be utilized to better understand genotype-phenotype relationships and to compare different organisms. To assist in the selection and development of strains with enhanced industrial utility, genome-scale models for L. casei ATCC 334, a well characterized strain, and strain 12A, a corn silage isolate, were constructed. Draft models were generated from RAST genome annotations using the Model SEED database and refined by evaluating ATP generating cycles, mass-and-charge-balances of reactions, and growth phenotypes. After the validation process was finished, we compared the metabolic networks of these two strains to identify metabolic, genetic and ortholog differences that may lead to different phenotypic behaviors. We conclude that the metabolic capabilities of the two networks are highly similar. The L. casei ATCC 334 model accounts for 1,040 reactions, 959 metabolites and 548 genes, while the L. casei 12A model accounts for 1,076 reactions, 979 metabolites and 640 genes. The developed L. casei ATCC 334 and 12A metabolic models will enable better understanding of the physiology of these organisms and be valuable tools in the development and selection of strains with enhanced utility in a variety of industrial applications. PMID:25365062

  5. Cloning, Purification and Characterization of the Collagenase ColA Expressed by Bacillus cereus ATCC 14579.

    PubMed

    Abfalter, Carmen M; Schönauer, Esther; Ponnuraj, Karthe; Huemer, Markus; Gadermaier, Gabriele; Regl, Christof; Briza, Peter; Ferreira, Fatima; Huber, Christian G; Brandstetter, Hans; Posselt, Gernot; Wessler, Silja

    2016-01-01

    Bacterial collagenases differ considerably in their structure and functions. The collagenases ColH and ColG from Clostridium histolyticum and ColA expressed by Clostridium perfringens are well-characterized collagenases that cleave triple-helical collagen, which were therefore termed as ´true´ collagenases. ColA from Bacillus cereus (B. cereus) has been added to the collection of true collagenases. However, the molecular characteristics of B. cereus ColA are less understood. In this study, we identified ColA as a secreted true collagenase from B. cereus ATCC 14579, which is transcriptionally controlled by the regulon phospholipase C regulator (PlcR). B. cereus ATCC 14579 ColA was cloned to express recombinant wildtype ColA (ColAwt) and mutated to a proteolytically inactive (ColAE501A) version. Recombinant ColAwt was tested for gelatinolytic and collagenolytic activities and ColAE501A was used for the production of a polyclonal anti-ColA antibody. Comparison of ColAwt activity with homologous proteases in additional strains of B. cereus sensu lato (B. cereus s.l.) and related clostridial collagenases revealed that B. cereus ATCC 14579 ColA is a highly active peptidolytic and collagenolytic protease. These findings could lead to a deeper insight into the function and mechanism of bacterial collagenases which are used in medical and biotechnological applications. PMID:27588686

  6. The sim operon facilitates the transport and metabolism of sucrose isomers in Lactobacillus casei ATCC 334.

    PubMed

    Thompson, John; Jakubovics, Nicholas; Abraham, Bindu; Hess, Sonja; Pikis, Andreas

    2008-05-01

    Inspection of the genome sequence of Lactobacillus casei ATCC 334 revealed two operons that might dissimilate the five isomers of sucrose. To test this hypothesis, cells of L. casei ATCC 334 were grown in a defined medium supplemented with various sugars, including each of the five isomeric disaccharides. Extracts prepared from cells grown on the sucrose isomers contained high levels of two polypeptides with M(r)s of approximately 50,000 and approximately 17,500. Neither protein was present in cells grown on glucose, maltose or sucrose. Proteomic, enzymatic, and Western blot analyses identified the approximately 50-kDa protein as an NAD(+)- and metal ion-dependent phospho-alpha-glucosidase. The oligomeric enzyme was purified, and a catalytic mechanism is proposed. The smaller polypeptide represented an EIIA component of the phosphoenolpyruvate-dependent sugar phosphotransferase system. Phospho-alpha-glucosidase and EIIA are encoded by genes at the LSEI_0369 (simA) and LSEI_0374 (simF) loci, respectively, in a block of seven genes comprising the sucrose isomer metabolism (sim) operon. Northern blot analyses provided evidence that three mRNA transcripts were up-regulated during logarithmic growth of L. casei ATCC 334 on sucrose isomers. Internal simA and simF gene probes hybridized to approximately 1.5- and approximately 1.3-kb transcripts, respectively. A 6.8-kb mRNA transcript was detected by both probes, which was indicative of cotranscription of the entire sim operon. PMID:18310337

  7. Dynamic proteome analysis of Cyanothece sp. ATCC 51142 under constant light

    SciTech Connect

    Aryal, Uma K.; Stockel, Jana; Welsh, Eric A.; Gritsenko, Marina A.; Nicora, Carrie D.; Koppenaal, David W.; Smith, Richard D.; Pakrasi, Himadri B.; Jacobs, Jon M.

    2012-02-03

    Understanding the dynamic nature of protein abundances provides insights into protein turnover not readily apparent from conventional, static mass spectrometry measurements. This level of data is particularly informative when surveying protein abundances in biological systems subjected to large perturbations or alterations in environment such as cyanobacteria. Our current analysis expands upon conventional proteomic approaches in cyanobacteria by measuring dynamic changes of the proteome using a 13C15N-L-leucine metabolic labeling in Cyanothece ATCC51142. Metabolically labeled Cyanothece ATCC51142 cells grown under nitrogen sufficient conditions in continuous light were monitored longitudinally for isotope incorporation over a 48 h period, revealing 422 proteins with dynamic changes in abundances. In particular, proteins involved in carbon fixation, pentose phosphate pathway, cellular protection, redox regulation, protein folding, assembly and degradation showed higher levels of isotope incorporation suggesting that these biochemical pathways are important for growth under non-diazotrophic conditions. Calculation of relative isotope abundances (RIA) values allowed to measure actual active protein synthesis over time for different biochemical pathways under non-diazotrophic conditions. Overall results demonstrated the utility of 'non-steady state' pulsed metabolic labeling for systems-wide dynamic quantification of the proteome in Cyanothece ATCC51142 that can also be applied to other cyanobacteria.

  8. Dynamic proteomic profiling of a unicellular cyanobacterium Cyanothece ATCC51142 across light-dark diurnal cycles

    SciTech Connect

    Aryal, Uma K.; Stockel, Jana; Krovvidi, Ravi K.; Gritsenko, Marina A.; Monroe, Matthew E.; Moore, Ronald J.; Koppenaal, David W.; Smith, Richard D.; Pakrasi, Himadri B.; Jacobs, Jon M.

    2011-12-01

    Unicellular cyanobacteria of the genus Cyanothece are recognized for their ability to execute nitrogen (N2)-fixation in the dark and photosynthesis in the light. Systems-wide dynamic proteomic profiling with mass spectrometry (MS) analysis reveals fundamental insights into the control and regulation of these functions. To expand upon the current knowledge of protein expression patterns in Cyanothece ATCC51142, we performed quantitative proteomic analysis using partial ("unsaturated") metabolic labeling and high mass accuracy LC-MS analysis. This dynamic proteomic profiling identified 721 actively synthesized proteins with significant temporal changes in expression throughout the light-dark cycles, of which 425 proteins matched with previously characterized cycling transcripts. The remaining 296 proteins contained a cluster of proteins uniquely involved in DNA replication and repair, protein degradation, tRNA synthesis and modification, transport and binding, and regulatory functions. Analysis of protein functions revealed that the expression of nitrogenase in the dark is mediated by higher respiration and glycogen metabolism. We have also shown that Cyanothece ATCC51142 utilizes alternative pathways for carbon (C) and nitrogen (N) acquisition, particularly, aspartic acid and glutamate as substrates of C and N, respectively. Utilization of phosphoketolase (PHK) pathway for the conversion of xylulose-5P to pyruvate and acetyl-P likely constitutes an alternative strategy to compensate higher ATP and NADPH demand. In conclusion, this study provides a deeper insight into how Cyanothece ATCC51142 modulates cellular functions to accommodate photosynthesis and N2-fixation within the single cell.

  9. Genome –Scale Reconstruction of Metabolic Networks of Lactobacillus casei ATCC 334 and 12A

    PubMed Central

    Vinay-Lara, Elena; Hamilton, Joshua J.; Stahl, Buffy; Broadbent, Jeff R.; Reed, Jennifer L.; Steele, James L.

    2014-01-01

    Lactobacillus casei strains are widely used in industry and the utility of this organism in these industrial applications is strain dependent. Hence, tools capable of predicting strain specific phenotypes would have utility in the selection of strains for specific industrial processes. Genome-scale metabolic models can be utilized to better understand genotype-phenotype relationships and to compare different organisms. To assist in the selection and development of strains with enhanced industrial utility, genome-scale models for L. casei ATCC 334, a well characterized strain, and strain 12A, a corn silage isolate, were constructed. Draft models were generated from RAST genome annotations using the Model SEED database and refined by evaluating ATP generating cycles, mass-and-charge-balances of reactions, and growth phenotypes. After the validation process was finished, we compared the metabolic networks of these two strains to identify metabolic, genetic and ortholog differences that may lead to different phenotypic behaviors. We conclude that the metabolic capabilities of the two networks are highly similar. The L. casei ATCC 334 model accounts for 1,040 reactions, 959 metabolites and 548 genes, while the L. casei 12A model accounts for 1,076 reactions, 979 metabolites and 640 genes. The developed L. casei ATCC 334 and 12A metabolic models will enable better understanding of the physiology of these organisms and be valuable tools in the development and selection of strains with enhanced utility in a variety of industrial applications. PMID:25365062

  10. Characterization of KfrA proteins encoded by a plasmid of Paenibacillus popilliae ATCC 14706T

    PubMed Central

    Iiyama, Kazuhiro; Mon, Hiroaki; Mori, Kazuki; Mitsudome, Takumi; Lee, Jae Man; Kusakabe, Takahiro; Tashiro, Kousuke; Asano, Shin-ichiro; Yasunaga-Aoki, Chisa

    2015-01-01

    A scaffold obtained from whole-genome shotgun sequencing of Paenibacillus popilliae ATCC 14706T shares partial homology with plasmids found in other strains of P. popilliae. PCR and sequencing for gap enclosure indicated that the scaffold originated from a 15,929-bp circular DNA. The restriction patterns of a plasmid isolated from P. popilliae ATCC 14706T were identical to those expected from the sequence; thus, this circular DNA was identified as a plasmid of ATCC 14706T and designated pPOP15.9. The plasmid encodes 17 putative open reading frames. Orfs 1, 5, 7, 8, and 9 are homologous to Orfs 11, 12, 15, 16, and 17, respectively. Orf1 and Orf11 are annotated as replication initiation proteins. Orf8 and Orf16 are homologs of KfrA, a plasmid-stabilizing protein in Gram-negative bacteria. Recombinant Orf8 and Orf16 proteins were assessed for the properties of KfrA. Indeed, they formed multimers and bound to inverted repeat sequences in upstream regions of both orf8 and orf16. A phylogenetic tree based on amino acid sequences of Orf8, Orf16 and Kfr proteins did not correlate with species lineage. PMID:25853059

  11. Effect of Heavy metals on the iron oxidizing ability of Thiobacillus ferrooxidans: Part 1, Effect of silver

    SciTech Connect

    De, G.C.; Pesic, B.

    1992-01-01

    The effect of silver ions on the iron oxidizing ability of Thiobacillus ferrooxidans was studied using electrochemical and other physics-chemical techniques. Electrochemical investigation was conducted using a method based on redox potential change. Experiments were performed by adding an aliquot of separately prepared concentrate of the bacteria into the solution of ferrous ion and monitoring the redox potential for at least one hour. Pyrite was used as the indicator electrode. Parameters examined were pH, microbial cell density, ferrous, ferric and silver ion concentration, temperature and preconditioning period of the bacteria with silver ions, etc. Results obtained demonstrate that the rate of ferrous ion oxidation is dependent on pH (optimum pH range is 1.5--2.0) and the substrate (i.e. Fe(II)) to microbial cell concentration ratio. The mechanism of the bacteria mediated oxidation of ferrous iron is remarkably sensitive to temperature changes. At the vicinity of the optimum temperature (i.e. 25[degree]C), the reaction is likely to be controlled by the diffusion of Fe (II) ions through the cell wall of the bacteria, whereas below the range 18--25[degree]C, reaction kinetics may be the rate controlling factor. In the presence of 10 mg/L silver, the reaction may be kinetically controlled over the temperature range 5.5--25[degree]C. Inhibition of microbial FE(II) oxidation in the presence of silver may take place via a mixed mechanism in which silver may bind with both the enzyme and the enzyme-substrate complex.

  12. Effects of oakmoss and its components on Acanthamoeba castellanii ATCC 30234 and the uptake of Legionella pneumophila JCM 7571 (ATCC 33152) into A. castellanii.

    PubMed

    Nomura, Harue; Isshiki, Yasunori; Sakuda, Keisuke; Sakuma, Katsuya; Kondo, Seiichi

    2015-01-01

    Acanthamoeba castellanii, a ubiquitous organism in water environments, is pathogenic toward humans and also is a host for bacteria of the genus Legionella, a causative agent of legionellosis. Oakmoss, a natural fragrance ingredient, and its components are antibacterial agents specifically against the genus Legionella. In the present study, oakmoss and its components were investigated for their amoebicidal activity against A. castellanii ATCC 30234 and the inhibitory effect on the uptake of L. pneumophila JCM 7571 (ATCC 33152) into A. castellanii. The oakmoss and its components 3-hydroxy-5-methylphenyl 2,4-dihydroxy-6-methylbenzoate(5), and 6,8-dihydroxy-3-pentyl-1H-isochromen-1-one (12) exhibited high amoebicidal activity (IC50 values; 10.5 ± 2.3, 16.3 ± 4.0 and 17.5 ± 2.8 μg/mL, respectively) after 48 h of treatment, which were equivalent to that of the reference compound, chlorhexidine gluconate. Pretreatment of L. pneumophila with sub-minimal inhibitory concentration of oakmoss, compound 5, 3-hydroxy-5-methylphenyl 2-hydroxy-4-methoxy-6-methylbenzoate (10) and 8-(2,4-dihydroxy-6-pentylphenoxy)-6-hydroxy-3-pentyl-1H-isochromen-1-one (14) obviously reduced the uptake of L. pneumophila into A.castellanii (p < 0.05).The inhibitory effect of compound 5 on the uptake of L. pneumophila was almost equivalent to that of ampicillin used as a reference. Thus, the oakmoss and its components were considered to be good candidates for disinfectants against not only genus Legionella but also A. castellanii. PMID:25817814

  13. Extraction, purification, and characterization of major outer membrane proteins from Wolinella recta ATCC 33238.

    PubMed Central

    Kennell, W L; Holt, S C

    1991-01-01

    The outer membrane of Wolinella recta ATCC 33238 was isolated by French pressure cell disruption and differential centrifugation. Outer membrane proteins (OMPs) were solubilized by Zwittergent 3.14 extraction and separated by DEAE-Sephacel ion-exchange chromatography. The major OMPs that were found in W. recta ATCC 33238 and in several other Wolinella spp. consisted of proteins with apparent molecular masses of 51, 45, and 43 kDa. These three conserved proteins were purified to essential homogeneity by one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and characterized chemically. Heating at between 75 and 100 degrees C revealed both the 43- and 51-kDa proteins to be heat modified from apparent molecular masses of 32 and 38 kDa, respectively. The 45-kDa protein was unmodified at all temperatures tested. Two-dimensional isoelectric focusing-SDS-PAGE revealed the 51-kDa protein to be composed of multiple pIs between a pH of 5.0 and greater than 8.0 while the 43- and 45-kDa proteins had a pI of approximately 6.0. N'-terminal amino acid sequence analysis of the first 30 to 40 amino acids and search of the Protein Identification Resource data base for similar proteins only revealed the 43-kDa protein to be similar to the P.69 OMP of Bordetella pertussis; however, the homology was weak (33%). Amino acid analysis revealed the 43-kDa protein to be noncharged and the 45- and 51-kDa proteins to be hydrophilic, containing between 38 to 42% polar residues but no cysteine. This study reports the purification and partial characterization of three conserved proteins in W. recta ATCC 33238. Images PMID:1894372

  14. Dynamic proteomic profiling of a unicellular cyanobacterium Cyanothece ATCC51142 across light-dark diurnal cycles

    PubMed Central

    2011-01-01

    Background Unicellular cyanobacteria of the genus Cyanothece are recognized for their ability to execute nitrogen (N2)-fixation in the dark and photosynthesis in the light. An understanding of these mechanistic processes in an integrated systems context should provide insights into how Cyanothece might be optimized for specialized environments and/or industrial purposes. Systems-wide dynamic proteomic profiling with mass spectrometry (MS) analysis should reveal fundamental insights into the control and regulation of these functions. Results To expand upon the current knowledge of protein expression patterns in Cyanothece ATCC51142, we performed quantitative proteomic analysis using partial ("unsaturated") metabolic labeling and high mass accuracy LC-MS analysis. This dynamic proteomic profiling identified 721 actively synthesized proteins with significant temporal changes in expression throughout the light-dark cycles, of which 425 proteins matched with previously characterized cycling transcripts. The remaining 296 proteins contained a cluster of proteins uniquely involved in DNA replication and repair, protein degradation, tRNA synthesis and modification, transport and binding, and regulatory functions. Functional classification of labeled proteins suggested that proteins involved in respiration and glycogen metabolism showed increased expression in the dark cycle together with nitrogenase, suggesting that N2-fixation is mediated by higher respiration and glycogen metabolism. Results indicated that Cyanothece ATCC51142 might utilize alternative pathways for carbon (C) and nitrogen (N) acquisition, particularly, aspartic acid and glutamate as substrates of C and N, respectively. Utilization of phosphoketolase (PHK) pathway for the conversion of xylulose-5P to pyruvate and acetyl-P likely constitutes an alternative strategy to compensate higher ATP and NADPH demand. Conclusion This study provides a deeper systems level insight into how Cyanothece ATCC51142

  15. Improved penicillin amidase production using a genetically engineered mutant of escherichia coli ATCC 11105

    SciTech Connect

    Robas, N.; Zouheiry, H.; Branlant, G.; Branlant, C. )

    1993-01-05

    Penicillin G amidase (PGA) is a key enzyme for the industrial production of penicillin G derivatives used in therapeutics. Escherichia coli ATCC 11105 is the more commonly used strain for PGA production. To improve enzyme yield, the authors constructed various recombinant E. coli HB 101 and ATCC 11105 strains. For each strain, PGA production was determined for various concentrations of glucose and phenylacetic acid (PAA) in the medium. The E. coli strain, G271, was identified as the best performer (800 U NIPAB/L). This strain was obtained as follows: an E. coli ATCC 11105 mutant (E. coli G133) was first selected based on a low negative effect of glucose on PGA production. This mutant was then transformed with a pBR322 derivative containing the PGA gene. Various experiments were made to try to understand the reason for the high productivity of E. coli G271. The host strain, E. coli G133, was found to be mutated in one (or more) gene(s) whose product(s) act(s) in trans on the PGA gene expression. Its growth is not inhibited by high glucose concentration in the medium. Interestingly, whereas glucose still exerts some negative effect on the PGA production by E. coli G133, PGA production by its transformant (E. coli G271) is stimulated by glucose. The reason for this stimulation is discussed. Transformation of E. coli G133 with a pBR322 derivative containing the HindIII fragment of the PGA gene, showed that the performance of E. coli G271 depends both upon the host strain properties and the plasmid structure. Study of the production by the less efficient E. coli HB101 derivatives brought some light on the mechanism of regulation of the PGA gene.

  16. Evaluating Chemical Mitigation of Salmonella Typhimurium ATCC 14028 in Animal Feed Ingredients.

    PubMed

    Cochrane, Roger A; Huss, Anne R; Aldrich, Gregory C; Stark, Charles R; Jones, Cassandra K

    2016-04-01

    Salmonella Typhimurium is a potential feed safety hazard in animal feed ingredients. Thermal mitigation of Salmonella spp. during rendering is effective but does not eliminate the potential for cross-contamination. Therefore, the objective of this experiment was to evaluate the effectiveness of chemicals to mitigate postrendering Salmonella Typhimurium ATCC 14028 contamination in rendered proteins over time. Treatments were arranged in a 6 × 4 factorial with six chemical treatments and four rendered protein meals. The chemical treatments included (i) control without chemical treatment, (ii) 0.3% commercial formaldehyde product, (iii) 2% essential oil blend, (iv) 2% medium chain fatty acid blend, (v) 3% organic acid blend, and (vi) 1% sodium bisulfate. The four rendered protein meals included (i) feather meal, (ii) blood meal, (iii) meat and bone meal, and (iv) poultry by-product meal. After matrices were chemically treated, they were inoculated with Salmonella Typhimurium ATCC 14028, stored at room temperature, and enumerated via plate counts on days 0, 1, 3, 7, 14, 21, and 42 postinoculation. The Salmonella concentration in ingredients treated with medium chain fatty acid and commercial formaldehyde were similar to one another (P = 0.23) but were 2 log lower than the control (P < 0.05). Ingredients treated with organic acids and essential oils also had lower Salmonella concentrations than the control (P < 0.05). Time also played a significant role in Salmonella mitigation, because all days except days 14 and 21 (P = 0.92) differed from one another. Rendered protein matrix also affected Salmonella stability, because concentrations in meat and bone meal and blood meal were similar to one another (P = 0.36) but were greater than levels in feather meal and poultry by-product meal (P < 0.05). In summary, chemical treatment and time both mitigated Salmonella Typhimurium ATCC 14028, but their effectiveness was matrix dependent. Time and chemical treatment with medium

  17. Complete genome sequence of Vibrio alginolyticus ATCC 33787(T) isolated from seawater with three native megaplasmids.

    PubMed

    Wang, Pengxia; Wen, Zhongling; Li, Baiyuan; Zeng, Zhenshun; Wang, Xiaoxue

    2016-08-01

    Vibrio alginolyticus, an opportunistic pathogen, is commonly associated with vibriosis in fish and shellfish and can also cause superficial and ear infections in humans. V. alginolyticus ATCC 33787(T) was originally isolated from seawater and has been used as one of the type strains for exploring the virulence factors of marine bacteria and for developing vaccine against vibriosis. Here we sequenced and assembled the whole genome of this strain, and identified three megaplasmids and three Type VI secretion systems, thus providing useful information for the study of virulence factors and for the development of vaccine for Vibrio. PMID:27211073

  18. Multicenter Investigation of Gepotidacin (GSK2140944) Agar Dilution Quality Control Determinations for Neisseria gonorrhoeae ATCC 49226.

    PubMed

    Jones, Ronald N; Fedler, Kelley A; Scangarella-Oman, Nicole E; Ross, James E; Flamm, Robert K

    2016-07-01

    Gepotidacin, a novel triazaacenaphthylene antibacterial agent, is the first in a new class of type IIA topoisomerase inhibitors with activity against many biothreat and conventional pathogens, including Neisseria gonorrhoeae To assist ongoing clinical studies of gepotidacin to treat gonorrhea, a multilaboratory quality assurance investigation determined the reference organism (N. gonorrhoeae ATCC 49226) quality control MIC range to be 0.25 to 1 μg/ml (88.8% of gepotidacin MIC results at the 0.5 μg/ml mode). PMID:27161642

  19. Genomic and genetic characterization of the bile stress response of probiotic Lactobacillus reuteri ATCC 55730.

    PubMed

    Whitehead, Kristi; Versalovic, James; Roos, Stefan; Britton, Robert A

    2008-03-01

    Probiotic bacteria encounter various stresses after ingestion by the host, including exposure to the low pH in the stomach and bile in the small intestine. The probiotic microorganism Lactobacillus reuteri ATCC 55730 has previously been shown to survive in the human small intestine. To address how L. reuteri can resist bile stress, we performed microarray experiments to determine gene expression changes that occur when the organism is exposed to physiological concentrations of bile. A wide variety of genes that displayed differential expression in the presence of bile indicated that the cells were dealing with several types of stress, including cell envelope stress, protein denaturation, and DNA damage. Mutations in three genes were found to decrease the strain's ability to survive bile exposure: lr1864, a Clp chaperone; lr0085, a gene of unknown function; and lr1516, a putative esterase. Mutations in two genes that form an operon, lr1584 (a multidrug resistance transporter in the major facilitator superfamily) and lr1582 (unknown function), were found to impair the strain's ability to restart growth in the presence of bile. This study provides insight into the possible mechanisms that L. reuteri ATCC 55730 may use to survive and grow in the presence of bile in the small intestine. PMID:18245259

  20. Phosphoketolase pathway dominates in Lactobacillus reuteri ATCC 55730 containing dual pathways for glycolysis.

    PubMed

    Arsköld, Emma; Lohmeier-Vogel, Elke; Cao, Rong; Roos, Stefan; Rådström, Peter; van Niel, Ed W J

    2008-01-01

    Metabolic flux analysis indicated that the heterofermentative Lactobacillus reuteri strain ATCC 55730 uses both the Embden-Meyerhof pathway (EMP) and phosphoketolase pathway (PKP) when glucose or sucrose is converted into the three-carbon intermediate stage of glycolysis. In all cases studied, the main flux is through the PKP, while the EMP is used as a shunt. In the exponential growth phase, 70%, 73%, and 84% of the flux goes through the PKP in cells metabolizing (i) glucose plus fructose, (ii) glucose alone, and (iii) sucrose alone, respectively. Analysis of the genome of L. reuteri ATCC 55730 confirmed the presence of the genes for both pathways. Further evidence for the simultaneous operation of two central carbon metabolic pathways was found through the detection of fructose-1,6-bisphosphate aldolase, phosphofructokinase, and phosphoglucoisomerase activities and the presence of phosphorylated EMP and PKP intermediates using in vitro 31P NMR. The maximum specific growth rate and biomass yield obtained on glucose were twice as low as on sucrose. This was the result of low ATP levels being present in glucose-metabolizing cells, although the ATP production flux was as high as in sucrose-metabolizing cells due to a twofold increase of enzyme activities in both glycolytic pathways. Growth performance on glucose could be improved by adding fructose as an external electron acceptor, suggesting that the observed behavior is due to a redox imbalance causing energy starvation. PMID:17965151

  1. Crystallization and crystallographic analysis of branching enzymes from Cyanothece sp. ATCC 51142.

    PubMed

    Hayashi, Mari; Suzuki, Ryuichiro; Colleoni, Christophe; Ball, Steven G; Fujita, Naoko; Suzuki, Eiji

    2015-08-01

    Several cyanobacterial species, including Cyanothece sp. ATCC 51142, remarkably have four isoforms of α-glucan branching enzymes (BEs). Based on their primary structures, they are classified into glycoside hydrolase (GH) family 13 (BE1, BE2 and BE3) or family 57 (GH57 BE). In the present study, GH13-type BEs from Cyanothece sp. ATCC 51142 (BE1, BE2 and BE3) have been overexpressed in Escherichia coli and biochemically characterized. The recombinant BE1 was crystallized by the hanging-drop vapour-diffusion method. Crystals of BE1 were obtained at 293 K in the presence of 0.2 M Mg(2+), 7-10%(w/v) ethanol, 0.1 M HEPES-NaOH pH 7.2-7.9. The crystals belonged to the tetragonal space group P41212, with unit-cell parameters a = b = 133.75, c = 185.90 Å, and diffracted to beyond 1.85 Å resolution. Matthews coefficient calculations suggested that the crystals of BE1 contained two molecules in the asymmetric unit. PMID:26249708

  2. In silico analysis of Clostridium acetobutylicum ATCC 824 metabolic response to an external electron supply.

    PubMed

    Gallardo, Roberto; Acevedo, Alejandro; Quintero, Julián; Paredes, Ivan; Conejeros, Raúl; Aroca, Germán

    2016-02-01

    The biological production of butanol has become an important research field and thanks to genome sequencing and annotation; genome-scale metabolic reconstructions have been developed for several Clostridium species. This work makes use of the iCAC490 model of Clostridium acetobutylicum ATCC 824 to analyze its metabolic capabilities and response to an external electron supply through a constraint-based approach using the Constraint-Based Reconstruction Analysis Toolbox. Several analyses were conducted, which included sensitivity, production envelope, and phenotypic phase planes. The model showed that the use of an external electron supply, which acts as co-reducing agent along with glucose-derived reducing power (electrofermentation), results in an increase in the butanol-specific productivity. However, a proportional increase in the butyrate uptake flux is required. Besides, the uptake of external butyrate leads to the coupling of butanol production and growth, which coincides with results reported in literature. Phenotypic phase planes showed that the reducing capacity becomes more limiting for growth at high butyrate uptake fluxes. An electron uptake flux allows the metabolism to reach the growth optimality line. Although the maximum butanol flux does not coincide with the growth optimality line, a butyrate uptake combined with an electron uptake flux would result in an increased butanol volumetric productivity, being a potential strategy to optimize the production of butanol by C. acetobutylicum ATCC 824. PMID:26650720

  3. Distinct adhesion of probiotic strain Lactobacillus casei ATCC 393 to rat intestinal mucosa.

    PubMed

    Saxami, Georgia; Ypsilantis, Petros; Sidira, Marianthi; Simopoulos, Constantinos; Kourkoutas, Yiannis; Galanis, Alex

    2012-08-01

    Adhesion to the intestine represents a critical parameter for probiotic action. In this study, the adhesion ability of Lactobacillus casei ATCC 393 to the gastrointestinal tract of Wistar rats was examined after single and daily administration of fermented milk containing either free or immobilized cells on apple pieces. The adhesion of the probiotic cells at the large intestine (cecum and colon) was recorded at levels ≥6 logCFU/g (suggested minimum levels for conferring a probiotic effect) following daily administration for 7 days by combining microbiological and strain-specific multiplex PCR analysis. Single dose administration resulted in slightly reduced counts (5 logCFU/g), while they were lower at the small intestine (duodenum, jejunum, ileum) (≤3 logCFU/g), indicating that adhesion was a targeted process. Of note, the levels of L. casei ATCC 393 were enhanced in the cecal and colon fluids both at single and daily administration of immobilized cells (6 and 7 logCFU/g, respectively). The adhesion of the GI tract was transient and thus daily consumption of probiotic products containing the specific strain is suggested as an important prerequisite for retaining its levels at an effective concentration. PMID:22554894

  4. Global transcriptome analysis of Bacillus cereus ATCC 14579 in response to silver nitrate stress

    PubMed Central

    2011-01-01

    Silver nanoparticles (AgNPs) were synthesized using Bacillus cereus strains. Earlier, we had synthesized monodispersive crystalline silver nanoparticles using B. cereus PGN1 and ATCC14579 strains. These strains have showed high level of resistance to silver nitrate (1 mM) but their global transcriptomic response has not been studied earlier. In this study, we investigated the cellular and metabolic response of B. cereus ATCC14579 treated with 1 mM silver nitrate for 30 & 60 min. Global expression profiling using genomic DNA microarray indicated that 10% (n = 524) of the total genes (n = 5234) represented on the microarray were up-regulated in the cells treated with silver nitrate. The majority of genes encoding for chaperones (GroEL), nutrient transporters, DNA replication, membrane proteins, etc. were up-regulated. A substantial number of the genes encoding chemotaxis and flagellar proteins were observed to be down-regulated. Motility assay of the silver nitrate treated cells revealed reduction in their chemotactic activity compared to the control cells. In addition, 14 distinct transcripts overexpressed from the 'empty' intergenic regions were also identified and proposed as stress-responsive non-coding small RNAs. PMID:22071005

  5. Using an established pre adipose cell line (ATCC CL 173) for studying chromium metabolism and biopotency

    SciTech Connect

    Hendricks, D.G.; Azuka, C. ); Johnson, B. )

    1991-03-15

    Studies concerning the mechanism by which chromium enhances insulin action and identification of chromium compounds which have high glucose tolerance factor activity have been limited by biological testing methods. The isolated rat adipose tissue assay has been commonly used. The pre-adipose cell line (ATCC CL 173) has many advantages over the isolated rat adipose tissue method including: uniformity of cells; increased viability of the cell cultures; can readily be grown in a low chromium media with a cell doubling time of about 18 hours; studies can be made on rapidly multiplying cells or on mature adipose cells and using rate of cell number increase, percent attachment of cells or cultures in an Omni Spec instrument avoid the use of radio labeled compounds. The ATCC CL 173 pre adipose cell line has been used to evaluate various chromium compounds for insulin like and insulin enhancing activity using physiological and pharmacological chromium levels. Rapidly dividing cells and mature adipose cells do not always react similarly with the same chromium compound. Cell response to a chromium compound and/or insulin also differs based on the growth media in which the cells have been maintained. Duration of metabolic studies as well as metabolite chosen also influence cellular response to chromium and insulin. Using this method for biological testing several chromium compounds have shown insulin like activity and a few show actual insulin potentiation.

  6. Ferulic acid transformation into the main vanilla aroma compounds by Amycolatopsis sp. ATCC 39116.

    PubMed

    Pérez-Rodríguez, Noelia; Oliveira, Ricardo Pinheiro de Souza; Agrasar, Ana María Torrado; Domínguez, José Manuel

    2016-02-01

    The wild strain Amycolatopsis sp. ATCC 39116 was explored in ferulic acid-based media to produce naturally the aroma components of the cured vanilla pod, namely vanillin,vanillic acid, and vanillyl alcohol. Other phenolic compounds(4-vinyl guaiacol, guaiacol, and protocatechuic acid) were also evaluated. The influence of medium composition,fermentation technology (batch or fed-batch), supplementation with vanillic acid, and inoculum concentration on ferulic acid biotransformation were evaluated. The results postulate the initial concentration of cell mass as the variable with the strongest impact on ferulic acid metabolization under the studied conditions. The highest amounts of vanillin and vanillic acid were achieved at intermediate values of cell mass.Vanillyl alcohol and protocatechuic acid were more closely linked to high cell mass concentrations. Conversely, 4-vinyl guaiacol reached its highest amount at the lowest amount of cell mass. Guaiacol was not detected in any case. Therefore,the initial cell concentration must be considered a critical parameter when using Amycolaptosis sp. ATCC 39116 for the production of vanillin and related compounds. PMID:26476645

  7. Production of fructosyltransferase by Aureobasidium sp. ATCC 20524 in batch and two-step batch cultures.

    PubMed

    Salinas, Martín A; Perotti, Nora I

    2009-01-01

    A comparison of fructosyltransferase (EC 2.4.1.9) production by Aureobasidium sp. ATCC 20524 in batch and two step batch cultures was investigated in a 1-l stirred tank reactor using a sucrose supply of 200 g/l. Results showed that the innovative cultivation in two step of Aureobasidium sp. produced more fructosyltransferase (FFase) than the single batch culture at the same sucrose concentration with a maximal enzyme production of 523 U/ml, which was 80.5% higher than the one obtained in the batch culture. The production of fructooligosaccharides (FOSs) was also analyzed; their concentration reached a maximum value of 160 g/l the first day in the two-step culture and 127 g/l in the single-batch mode. The use of the two-step batch culture with Aureobasidium sp. ATCC 20524 in allowing the microorganism to grow up prior to the induction of sucrose (second step), proved to be a powerful method for producing fructosyltransferase and FOSs. PMID:18810518

  8. Assessment of in vitro removal of cholesterol oxidation products by Lactobacillus casei ATCC334.

    PubMed

    Machorro-Méndez, I A; Hernández-Mendoza, A; Cardenia, V; Rodriguez-Estrada, M T; Lercker, G; Spinelli, F; Cellini, A; García, H S

    2013-11-01

    Cholesterol oxidation products (COPs) are a group of compounds formed during processing and storage of foods from animal origin. After ingestion, COPs are absorbed in the intestine and can be distributed to serum and various tissues, potentially promoting a variety of toxic effects. Therefore, inhibition of their intestinal absorption may contribute to reduce the health risks associated with dietary intake of COPs. Some studies have shown that drugs and dietary compounds may inhibit the intestinal absorption of dietary COPs. However, proven cholesterol- and/or food toxins-binding lactic acid bacteria have not been previously evaluated as potential COPs removal agents. The aim of this study was to assess the ability of Lactobacillus casei ATCC334 to remove COPs in aqueous solution. Results showed the ability of both growing and resting cells to remove COPs (ca. 30-60%). All COPs-bacterium interactions were specific and partly reversible, being resting cells the most efficient for COPs removal in a ranking order of 7-KC > 7α-OH/7β-OH > triol > 5,6β-EP > 5,6α-EP > 25-OH. Binding to the cell wall and/or cell membrane incorporation appears to be the most likely mechanisms involved on COPs removal by L. casei ATCC 334. PMID:23848962

  9. Composition of the carbohydrate granules of the cyanobacterium, Cyanothece sp. strain ATCC 51142

    NASA Technical Reports Server (NTRS)

    Schneegurt, M. A.; Sherman, D. M.; Sherman, L. A.; Mitchell, C. A. (Principal Investigator)

    1997-01-01

    Cyanothece sp. strain ATCC 51142 is an aerobic, unicellular, diazotrophic cyanobacterium that temporally separates O2-sensitive N2 fixation from oxygenic photosynthesis. The energy and reducing power needed for N2 fixation appears to be generated by an active respiratory apparatus that utilizes the contents of large interthylakoidal carbohydrate granules. We report here on the carbohydrate and protein composition of the granules of Cyanothece sp. strain ATCC 51142. The carbohydrate component is a glucose homopolymer with branches every nine residues and is chemically identical to glycogen. Granule-associated protein fractions showed temporal changes in the number of proteins and their abundance during the metabolic oscillations observed under diazotrophic conditions. There also were temporal changes in the protein pattern of the granule-depleted supernatant fractions from diazotrophic cultures. None of the granule-associated proteins crossreacted with antisera directed against several glycogen-metabolizing enzymes or nitrogenase, although these proteins were tentatively identified in supernatant fractions. It is suggested that the granule-associated proteins are structural proteins required to maintain a complex granule architecture.

  10. Isolation and Characterization of a Novel Virulent Phage of Lactobacillus casei ATCC 393.

    PubMed

    Zhang, Xi; Lan, Yu; Jiao, Wenchao; Li, Yijing; Tang, Lijie; Jiang, Yanping; Cui, Wen; Qiao, Xinyuan

    2015-12-01

    A new virulent phage (Lcb) of Lactobacillus casei ATCC 393 was isolated from Chinese sauerkraut. It was specific to L. casei ATCC 393. Electron micrograph revealed that it had an icosahedral head (60.2 ± 0.8 nm in diameter) and a long tail (251 ± 2.6 nm). It belonged to the Siphoviridae family. The genome of phage Lcb was estimated to be approximately 40 kb and did not contain cohesive ends. One-step growth kinetics of its lytic development revealed latent and burst periods of 75 and 45 min, respectively, with a burst size of 16 PFU per infected cell. The phage was able to survive in a pH range between 4 and 11. However, a treatment of 70 °C for 30 min and 75% ethanol or isopropanol for 20 min was observed to inactivate phage Lcb thoroughly. The presence of both Ca(2+) and Mg(2+) showed a little influence on phage adsorption, but they were indispensable to gain complete lysis and improve plaque formation. The adsorption kinetics were similar on viable or nonviable cells, and high adsorption rates maintained between 10 and 37 °C. The highest adsorption rate was at 30 °C. This study increased the knowledge on phages of L. casei. The characterization of phage Lcb is helpful to establish a basis for adopting effective strategies to control phage attack in industry. PMID:26123178

  11. Heterologous expression of Streptomyces clavuligerus ATCC 27064 cephamycin C gene cluster.

    PubMed

    Martínez-Burgo, Y; Álvarez-Álvarez, R; Pérez-Redondo, R; Liras, P

    2014-09-30

    The Streptomyces clavuligerus cephamycin C gene cluster has been subcloned in a SuperCos-derived cosmid and introduced in Streptomyces flavogriseus ATCC 33331, Streptomyces coelicolor M1146 and Streptomyces albus J1074. The exconjugant strains were supplemented with an additional copy of the S. clavuligerus cephamycin regulatory activator gene, ccaRC, expressed from the constitutive Pfur promoter. Only S. flavogriseus-derived exconjugants produced a compound active against Escherichia coli ESS22-31 that was characterized by HPLC-MS as cephamycin C. The presence of an additional ccaR copy resulted in about 40-fold increase in cephamycin C production. Optimal heterologous cephamycin C production was in the order of 9% in relation to that of S. clavuligerus ATCC 27064. RT-qPCR studies indicated that ccaRC expression in S. flavogriseus::[SCos-CF] was 7% of that in S. clavuligerus and increased to 47% when supplemented with a copy of Pfur-ccaR. The effect on cephamycin biosynthesis gene expression was thus improved but not in an uniform manner for every gene. In heterologous strains, integration of the cephamycin cluster results in a ccaR-independent increased resistance to penicillin, cephalosporin and cefoxitin, what corresponds well to the strong expression of the pcbR and pbpA genes in S. flavogriseus-derived strains. PMID:24975573

  12. Next-generation sequencing-based transcriptome analysis of L-lysine-producing Corynebacterium glutamicum ATCC 21300 strain.

    PubMed

    Kim, Hong-Il; Nam, Jae-Young; Cho, Jae-Yong; Lee, Chang-Soo; Park, Young-Jin

    2013-12-01

    In the present study, 151 genes showed a significant change in their expression levels in Corynebacterium glutamicum ATCC 21300 compared with those of C. glutamicum ATCC 13032. Of these 151 genes, 56 genes (2%) were up-regulated and 95 genes (3%) were down-regulated. RNA sequencing analysis also revealed that 11 genes, involved in the L-lysine biosynthetic pathway of C. glutamicum, were up- or down-regulated compared with those of C. glutamicum ATCC 13032. Of the 151 genes, 10 genes were identified to have mutations including SNP (9 genes) and InDel (1 gene). This information will be useful for genome breeding of C. glutamicum to develop an industrial amino acid-producing strain with minimal mutation. PMID:24385368

  13. Use of sulfur-oxidizing bacteria as recognition elements in hydrogen sulfide biosensing system.

    PubMed

    Janfada, Behdokht; Yazdian, Fatemeh; Amoabediny, Ghassem; Rahaie, Mahdi

    2015-01-01

    Four sulfur-oxidizing bacteria (Thiobacillus thioparus, Acidithiobacillus thiooxidans PTCC1717, Acidithiobacillus ferrooxidans PTCC1646, and Acidithiobacillus ferrooxidans PTCC1647) were used as biorecognition elements in a hydrogen sulfide biosensing system. All the experiments were performed in 0.1 M phosphate buffer solution containing 1-20 ppm H2S with optimum pH and temperature for each species. Although H2 S was applied to the biosensing system, the dissolved O2 content decreased. Dissolved O2 consumed by cells in both free and immobilized forms was measured using a dissolved oxygen sensor. Free bacterial cells exhibit fast response (<200 Sec). Immobilization of the cells on polyvinyl alcohol was optimized using an analytical software. Immobilized A. ferrooxidans and A. thiooxidans retained more than 50% of activity after 30 days of immobilization. According to the data, A. thiooxidans and A. ferrooxidans are appropriate species for hydrogen sulfide biosensor. PMID:25158614

  14. Characterization of the Calcination Products of the Precipitates Obtained from the Bio-Oxidation with Thiobacillus Ferrooxidans of Sulphuric Water Pickling Liquors

    NASA Astrophysics Data System (ADS)

    Marco, J. F.; Gancedo, J. R.; López, F. A.

    1998-12-01

    The characterization of the calcination products of the precipitates obtained from the bio-oxidation with Thiobacillus ferrooxidans of sulphuric water pickling liquors has been carried out by means of Mössbauer spectroscopy, x-ray powder diffraction, infrared spectroscopy and transmission electron microscopy. The results show that a full transformation of the precipitates into α-Fe2O3 is achieved at temperatures higher than 850°C. Calcination at 700°C during two hours results in the formation of α-Fe2O3, ζ-Fe2O3 and Fe12O3(SO4)15. The Mössbauer parameters of ζ-Fe2O3 and Fe12O3(SO4)15 at 298 and 17K are reported.

  15. High-Quality Draft Genome Sequence of Aneurinibacillus migulanus ATCC 9999T (DSM 2895), a Gramicidin S-Producing Bacterium Isolated from Garden Soil

    PubMed Central

    Wang, Jie-ping; Liu, Guo-hong; Ge, Ci-bin; Xiao, Rong-feng; Zheng, Xue-fang; Shi, Huai

    2015-01-01

    Aneurinibacillus migulanus ATCC 9999T (DSM 2895) is a Gram-positive, round-spore-forming, and gramicidin S-producing bacterium. Here, we report the 6.35-Mb high-quality draft genome sequence of A. migulanus ATCC 9999T, which will provide useful information for the genomic taxonomy and phylogenomics of Bacillus-like bacteria. PMID:26494674

  16. High-Quality Draft Genome Sequence of Aneurinibacillus migulanus ATCC 9999T (DSM 2895), a Gramicidin S-Producing Bacterium Isolated from Garden Soil.

    PubMed

    Wang, Jie-Ping; Liu, Bo; Liu, Guo-Hong; Ge, Ci-Bin; Xiao, Rong-Feng; Zheng, Xue-Fang; Shi, Huai

    2015-01-01

    Aneurinibacillus migulanus ATCC 9999(T) (DSM 2895) is a Gram-positive, round-spore-forming, and gramicidin S-producing bacterium. Here, we report the 6.35-Mb high-quality draft genome sequence of A. migulanus ATCC 9999(T), which will provide useful information for the genomic taxonomy and phylogenomics of Bacillus-like bacteria. PMID:26494674

  17. Effect of continuous light on diurnal rhythms in Cyanothece sp. ATCC 51142

    PubMed Central

    Elvitigala, Thanura; Stöckel, Jana; Ghosh, Bijoy K; Pakrasi, Himadri B

    2009-01-01

    Background Life on earth is strongly affected by alternating day and night cycles. Accordingly, many organisms have evolved an internal timekeeping system with a period of approximately 24 hours. Cyanobacteria are the only known prokaryotes with robust rhythms under control of a central clock. Numerous studies have been conducted to elucidate components of the circadian clock and to identify circadian-controlled genes. However, the complex interactions between endogenous circadian rhythms and external cues are currently not well understood, and a direct and mathematical based comparison between light-mediated and circadian-controlled gene expression is still outstanding. Therefore, we combined and analyzed data from two independent microarray experiments, previously performed under alternating light-dark and continuous light conditions in Cyanothece sp. ATCC 51142, and sought to classify light responsive and circadian controlled genes. Results Fourier Score-based methods together with random permutations and False Discovery Rates were used to identify genes with oscillatory expression patterns, and an angular distance based criterion was applied to recognize transient behaviors in gene expression under constant light conditions. Compared to previously reported mathematical approaches, the combination of these methods also facilitated the detection of modified amplitudes and phase-shifts of gene expression. Our analysis showed that the majority of diurnally regulated genes, essentially those genes that are maximally expressed during the middle of the light and dark period, are in fact light responsive. In contrast, most of the circadian controlled genes are up-regulated during the beginning of the dark or subjective dark, and are greatly enriched for genes associated with energy metabolism. Many of the circadian controlled and light responsive genes are found in gene clusters within the Cyanothece sp. ATCC 51142 genome. Interestingly, in addition to cyclic

  18. Lactobacillus reuteri ATCC 55730 and L22 display probiotic potential in vitro and protect against Salmonella-induced pullorum disease in a chick model of infection.

    PubMed

    Zhang, Dexian; Li, Rui; Li, Jichang

    2012-08-01

    Lactobacillus reuteri ATCC 55730 (L. reuteri ATCC 55730) and L. reuteri L22 were studied for their probiotic potential. These two strains were able to produce an antimicrobial substance, termed reuterin, the maximum production of reuterin by these two strains was detected in the late logarithmic growth phase (16 h in MRS and 20 h in LB broths). These two strains could significantly reduce the growth of Salmonella pullorum ATCC 9120 in MRS broth, L. reuteri ATCC 55730 with a reduction of 48.2±4.15% (in 5 log) and 89.7±2.59% (in 4 log) respectively, at the same time, L. reuteri L22 was 69.4±3.48% (in 5 log) and 80.4±3.22% respectively. L. reuteri ATCC 55730 was active against the majority of the pathogenic species, including S. pullorum ATCC 9120 and Escherichia coli O(78), while L. reuteri L22 was not as effective as L. reuteri ATCC 55730. The two potential strains were found to survive variably at pH 2.5 and were unaffected by bile salts, while neither of the strains was haemolytic. Moreover, L. reuteri ATCC 55730 exhibited variable susceptibility towards commonly used antibiotics; but L. reuteri L22 showed resistant to most antibiotics in this study. L. reuteri ATCC 55730 consequently was found to significantly increase survival rate in a Salmonella-induced pullorum disease model in chick. To conclude, strain L. reuteri ATCC 55730 possesses desirable probiotic properties, such as antimicrobial activity and immunomodulation in vitro, which were confirmed in vivo by the use of animal models. PMID:21764090

  19. Pore-forming ability of major outer membrane proteins from Wolinella recta ATCC 33238.

    PubMed Central

    Kennell, W L; Egli, C; Hancock, R E; Holt, S C

    1992-01-01

    Three major outer membrane proteins with apparent molecular masses of 43, 45, and 51 kDa were purified from Wolinella recta ATCC 33238, and their pore-forming abilities were determined by the black lipid bilayer method. The non-heat-modifiable 45-kDa protein (Omp 45) showed no pore-forming activity even at high KCl concentrations. The single-channel conductances in 1 M KCl of the heat-modifiable proteins with apparent molecular masses of 43 kDa (Omp 43) and 51 kDa (Omp 51) were 0.49 and 0.60 nS, respectively. The proteins formed nonselective channels and, as determined by experiments of ion selectivity and zero-current potential, were weakly anion selective. Images PMID:1370429

  20. Effects of Salt Stress on Carbohydrate Metabolism of Lactobacillus plantarum ATCC 14917.

    PubMed

    Wang, Pingping; Wu, Zhen; Wu, Jing; Pan, Daodong; Zeng, Xiaoqun; Cheng, Kemeng

    2016-10-01

    Lactic acid bacteria are widely used in fermented foods, especially cheese products. In this study, we observed the salt tolerance of Lactobacillus plantarum ATCC 14917 after exposure to different concentrations of NaCl in MRS medium. Quantitative proteomic profiles using two-dimensional electrophoresis identified 384 proteins, of which 26 were upregulated and 31 downregulated. Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry was then used to identify 11 proteins, of which three were linked to carbohydrate metabolism. The downregulation of carbamoyl phosphate synthase in carbohydrate metabolism revealed a bacterial regulation mechanism to save energy in order to survive during the salt tolerance. Other proteins were found involved in transcription-translation processes, fatty acid biosynthesis, and the primary metabolic process. PMID:27342422

  1. Ala(0)-actagardine, a new lantibiotic from cultures of Actinoplanes liguriae ATCC 31048.

    PubMed

    Vértesy, L; Aretz, W; Bonnefoy, A; Ehlers, E; Kurz, M; Markus, A; Schiell, M; Vogel, M; Wink, J; Kogler, H

    1999-08-01

    The actagardine-producing strain Actinoplanes liguriae ATCC 31048, forms an additional lantibiotic when it is cultured on mannitol and soya meal. The new compound, Ala(0)-actagardine (1), has been isolated by solid-phase extraction followed by a two-step chromatographic separation. The molecular formula of 1 is C84H129N21O25S4. Its chemical structure was determined by 2D-NMR analysis and was further confirmed by an amino acid analysis, Edman degradation, and partial synthesis from actagardine. 1 exhibits a slightly higher biological activity than the parent compound actagardine. The synthetic analogs Lys(0)-actagardine (2) and Ile(0)-actagardine (3) demonstrate also antibacterial activities and emphasize the importance of the N-terminus for further derivatization. PMID:10580386

  2. Characterization of the pyoverdines of Azotobacter vinelandii ATCC 12837 with regard to heterogeneity.

    PubMed

    Menhart, N; Thariath, A; Viswanatha, T

    1991-01-01

    Azotobacter vinelandii strain ATCC 12837 produces peptide siderophores of the general class known as pyoverdines. In the past, it was assumed that a single well-defined pyoverdine was produced by each parent microorganism. However, there are a number of reports of incompletely characterized pyoverdines that demonstrate heterogeneity in pyoverdine preparations obtained from a single organism, but the nature of this phenomena has not been explained. This study shows that A. vinelandii does indeed produce more than one pyoverdine and that these compounds differ in their peptide components. The metabolism of these siderophores suggests that only one of them is a true siderophore while the others are metabolic byproducts. It was demonstrated that this phenomenon is likely due to intrinsic limitations of the synthetase complex involved in the biosynthesis of these compounds. Characterization of two of the major pyoverdines produced demonstrated that they are novel compounds, although they belonged to the Azotobacter-type family of pyoverdines. PMID:1838001

  3. Pullulan Production by Aureobasidium pullulans ATCC 201253 Cells Adsorbed onto Cellulose Anion and Cation Exchangers

    PubMed Central

    West, Thomas P.

    2012-01-01

    The anion exchanger phosphocellulose and the cation exchanger triethylaminoethyl cellulose were used to immobilize cells of the fungus Aureobasidium pullulans ATCC 201253 and the adsorbed cells were subsequently investigated for their ability to produce the polysaccharide pullulan using batch fermentation. The cells adsorbed on the triethylaminoethyl cellulose at pH 7.5 produced higher pullulan levels than those cells immobilized on phosphocellulose at pH 4.0 for 2 cycles of 168 h at 30 °C. Relative to the initial cycle of 168 h, pullulan production by the cells immobilized on the triethylaminoethyl cellulose decreased slightly after 168 h of the second production cycle while pullulan production by the phosphocellulose-immobilized cells remained about the same after 168 h of the second production cycle. PMID:23762749

  4. Isolation of a mutant strain of Pseudomonas sp ATCC 31461 exhibiting elevated polysaccharide production.

    PubMed

    West, T P

    2002-10-01

    A mutant strain of the bacterium Pseudomonas sp. ATCC 31461 that exhibited elevated production of the polysaccharide gellan on glucose or corn syrup as a carbon source was isolated. Gellan production by the mutant strain was about twofold higher than its parent strain on glucose or corn syrup after 48 h of growth, and about 1.4-fold higher after 72 h. An increase in biomass production was not correlated with enhanced gellan synthesis by the mutant strain. The increased gellan production by the mutant strain on either carbon source resulted in an increase in its culture medium viscosity and the viscosity of the isolated polysaccharide produced by glucose-grown cells. No differences in the glucuronic acid content of the polysaccharides produced by the mutant and parent strains were observed. PMID:12355317

  5. Response of electrically stimulated cells of Pseudomonas oleovorans strain ATCC 29347 suspended in silicone oil.

    PubMed

    Anglade, J; Hirschler, A; Le Petit, J; Matheron, R; Scarpitta, A; Iacazio, G

    2001-05-15

    A high intensity direct current was applied for more than 10 min onto a bacterial suspension of Pseudomonas oleovorans ATCC 29347 suspended in silicone oil. The application of a gradually increased electric field from 0 to 2500 V x cm(-1) resulted in a decrease of the optical density of the bacterial suspension and the occurrence of a peak current of several hundred microA for living cells instead of a linear increase (few microA) for killed or lyophilised cells. This procedure is not only a rapid way of investigating the living state of cell cultures but also an efficient experimental tool to study the cellular effects of a controlled electrical stress. PMID:11356578

  6. Desulfurization and denitrogenation of heavy gas oil by Rhodococcus erythropolis ATCC 4277.

    PubMed

    Maass, D; Todescato, D; Moritz, D E; Oliveira, J Vladimir; Oliveira, D; Ulson de Souza, A A; Guelli Souza, S M A

    2015-08-01

    Some of the noxious atmospheric pollutants such as nitrogen and sulfur dioxides come from the fossil fuel combustion. Biodesulfurization and biodenitrogenation are processes which remove those pollutants through the action of microorganisms. The ability of sulfur and nitrogen removal by the strain Rhodococcus erythropolis ATCC 4277 was tested in a biphasic system containing different heavy gas oil concentrations in a batch reactor. Heavy gas oil is an important fraction of petroleum, because after passing through, the vacuum distillation is incorporated into diesel oil. This strain was able to remove about 40% of the nitrogen and sulfur present in the gas heavy oil. Additionally, no growth inhibition occurred even when in the presence of pure heavy gas oil. Results present in this work are considered relevant for the development of biocatalytic processes for nitrogen and sulfur removal toward building feasible industrial applications. PMID:25759162

  7. Closing the Carbon Balance for Fermentation by Clostridium thermocellum (ATCC 27405)

    SciTech Connect

    Ellis, Lucas D; Holwerda, Evert K; Hogsett, David; Rogers, Steve; Shao, Xiongjun; Tschaplinski, Timothy J; Thorne, Phil; Lynd, L.

    2012-01-01

    Our lab and most others have not been able to close a carbon balance for fermentation by the thermophilic, cellulolytic anaerobe, Clostridium thermocellum. We undertook a detailed accounting of product formation in C. thermocellum ATCC 27405. Elemental analysis revealed that for both cellulose (Avicel) and cellobiose, {>=}92% of the substrate carbon utilized could be accounted for in the pellet, supernatant and off-gas when including sampling. However, 11.1% of the original substrate carbon was found in the liquid phase and not in the form of commonly-measured fermentation products - ethanol, acetate, lactate, and formate. Further detailed analysis revealed all the products to be <720 da and have not usually been associated with C. thermocellum fermentation, including malate, pyruvate, uracil, soluble glucans, and extracellular free amino acids. By accounting for these products, 92.9% and 93.2% of the final product carbon was identified during growth on cellobiose and Avicel, respectively.

  8. Biodegradation of bisphenol A and its halogenated analogues by Cunninghamella elegans ATCC36112.

    PubMed

    Keum, Young Soo; Lee, Hye Ri; Park, Hee Won; Kim, Jeong-Han

    2010-11-01

    Bisphenol A and its halogenated analogues are commonly used industrial chemicals with strong toxicological effects over many organisms. In this study, metabolic fate of bisphenol A and its halogenated analogues were evaluated with Cunninghamella elegans ATCC36112. Bisphenol A and related analogues were rapidly transformed into several metabolites by C. elegans within 2-4 days. Detailed analysis of metabolites reveals that both phase I and II metabolism occurred in C. elegans. Cytochrome P450-dependent hydroxylation was observed in BPA. However, major reaction with bisphenol A and analogues with 1-2 halogen atoms were the formation of glucose-conjugate, not being inhibited by cytochrome P450 inhibitor. Overall metabolic rates decreased with increasing number of substitution at 2- and 6-position of BPA structures, which may be consequences of limited bioavailability or steric hindrance to conjugate-forming reaction. Information from the current study will provide detailed insights over the fungal metabolism of BPA and analogues. PMID:20455075

  9. Nisin production from Lactococcus lactis A.T.C.C. 7962 using supplemented whey permeate.

    PubMed

    Flôres, S H; Alegre, R M

    2001-10-01

    The influence of pH control and aeration (20% dissolved oxygen) on nisin production in a supplemented cheese whey permeate was examined during batch fermentation with Lactococcus lactis subsp. lactis A.T.C.C. 7962. A maximum nisin activity of 5280 i.u./ml of medium was observed in the raw extract of nisin after 9 h of fermentation with a constant pH at 4.9. However, the fermentation was continued until 24 h, when a decrease in the nisin activity was observed. The pH control did not influence the nisin production and aeration of the culture medium increased cell growth (biomass) but not nisin activity. The yeast Kluyveromyces marxianus, used as an alternative method to control pH, has not been efficient. PMID:11592916

  10. Genome Assembly of Methicillin-Resistant Quality Control Strain Staphylococcus aureus CDC73-57501 (ATCC 29247).

    PubMed

    Daligault, H E; Davenport, K W; Minogue, T D; Bishop-Lilly, K A; Broomall, S M; Bruce, D C; Chain, P S; Coyne, S R; Freitas, T; Frey, K G; Gibbons, H S; Jaissle, J; Lo, C-C; Meincke, L; Munk, A C; Redden, C L; Rosenzweig, C N; Johnson, S L

    2014-01-01

    Staphylococcus aureus is a major cause of bacterial infections in the United States, with high percentages of serious infections resistant to a variety of β-lactam antibiotics. Here, we present the scaffolded genome assembly into 16 contigs of S. aureus CDC73-57501 (ATCC 29247), a methicillin-resistant quality control strain. PMID:25278527

  11. Genome Assembly of Methicillin-Resistant Quality Control Strain Staphylococcus aureus CDC73-57501 (ATCC 29247)

    PubMed Central

    Daligault, H. E.; Davenport, K. W.; Minogue, T. D.; Bishop-Lilly, K. A.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Freitas, T.; Frey, K. G.; Gibbons, H. S.; Jaissle, J.; Lo, C.-C.; Meincke, L.; Munk, A. C.; Redden, C. L.; Rosenzweig, C. N.

    2014-01-01

    Staphylococcus aureus is a major cause of bacterial infections in the United States, with high percentages of serious infections resistant to a variety of β-lactam antibiotics. Here, we present the scaffolded genome assembly into 16 contigs of S. aureus CDC73-57501 (ATCC 29247), a methicillin-resistant quality control strain. PMID:25278527

  12. Complete Genome Sequence of Gluconacetobacter hansenii Strain NQ5 (ATCC 53582), an Efficient Producer of Bacterial Cellulose

    PubMed Central

    Pfeffer, Sarah; Mehta, Kalpa

    2016-01-01

    This study reports the release of the complete nucleotide sequence of Gluconacetobacter hansenii strain NQ5 (ATCC 53582). This strain was isolated by R. Malcolm Brown, Jr. in a sugar mill in North Queensland, Australia, and is an efficient producer of bacterial cellulose. The elucidation of the genome will contribute to the study of the molecular mechanisms necessary for cellulose biosynthesis. PMID:27516505

  13. A murine oral model for Mycobacterium avium subsp. paratuberculosis infection and immunomodulation with Lactobacillus casei ATCC 334.

    PubMed

    Cooney, Meagan A; Steele, James L; Steinberg, Howard; Talaat, Adel M

    2014-01-01

    Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) the causative agent of Johne's disease, is one of the most serious infectious diseases in dairy cattle worldwide. Due to the chronic nature of this disease and no feasible control strategy, it is essential to have an efficient animal model which is representative of the natural route of infection as well as a viable treatment option. In this report, we evaluated the effect of different doses of M. paratuberculosis in their ability to colonize murine tissues following oral delivery and the ability of Lactobacillus casei ATCC 334, a nascent probiotic, to combat paratuberculosis. Oral inoculation of mice was able to establish paratuberculosis in a dose-dependent manner. Two consecutive doses of approximately 10(9) CFU per mouse resulted in a disseminated infection, whereas lower doses were not efficient to establish infection. All inoculated mice were colonized with M. paratuberculosis, maintained infection for up to 24 weeks post infection and generated immune responses that reflect M. paratuberculosis infection in cattle. Notably, oral administration of L. casei ATCC 334 did not reduce the level of M. paratuberculosis colonization in treated animals. Interestingly, cytokine responses and histology indicated a trend for the immunomodulation and reduction of pathology in animals receiving L. casei ATCC 334 treatment. Overall, a reproducible oral model of paratuberculosis in mice was established that could be used for future vaccine experiments. Although the L. casei ATCC 334 was not a promising candidate for controlling paratuberculosis, we established a protocol to screen other probiotic candidates. PMID:24551602

  14. A murine oral model for Mycobacterium avium subsp. paratuberculosis infection and immunomodulation with Lactobacillus casei ATCC 334

    PubMed Central

    Cooney, Meagan A.; Steele, James L.; Steinberg, Howard; Talaat, Adel M.

    2014-01-01

    Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) the causative agent of Johne's disease, is one of the most serious infectious diseases in dairy cattle worldwide. Due to the chronic nature of this disease and no feasible control strategy, it is essential to have an efficient animal model which is representative of the natural route of infection as well as a viable treatment option. In this report, we evaluated the effect of different doses of M. paratuberculosis in their ability to colonize murine tissues following oral delivery and the ability of Lactobacillus casei ATCC 334, a nascent probiotic, to combat paratuberculosis. Oral inoculation of mice was able to establish paratuberculosis in a dose-dependent manner. Two consecutive doses of approximately 109 CFU per mouse resulted in a disseminated infection, whereas lower doses were not efficient to establish infection. All inoculated mice were colonized with M. paratuberculosis, maintained infection for up to 24 weeks post infection and generated immune responses that reflect M. paratuberculosis infection in cattle. Notably, oral administration of L. casei ATCC 334 did not reduce the level of M. paratuberculosis colonization in treated animals. Interestingly, cytokine responses and histology indicated a trend for the immunomodulation and reduction of pathology in animals receiving L. casei ATCC 334 treatment. Overall, a reproducible oral model of paratuberculosis in mice was established that could be used for future vaccine experiments. Although the L. casei ATCC 334 was not a promising candidate for controlling paratuberculosis, we established a protocol to screen other probiotic candidates. PMID:24551602

  15. Fe(III) stimulates 3-methylindole and 4-methylphenol production in swine lagoon enrichments and Clostridium scatologenes ATCC 25775

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: To determine the effects of anaerobic electron acceptors on 3-methylindole (3-MI) and 4-methylphenol (4-MP) production in swine waste lagoon enrichments and Clostridium scatologenes ATCC 25775. Methods and Results: Swine waste lagoon sediment was incubated anaerobically in tryptone-yeast ext...

  16. Genome Sequence of Streptococcus phocae subsp. phocae Strain ATCC 51973T Isolated from a Harbor Seal (Phoca vitulina)

    PubMed Central

    Poblete-Morales, Matías

    2015-01-01

    Streptococcus phocae subsp. phocae is a pathogen that affects different pinniped and mammalian species. This announcement reports the genome sequence of the type strain ATCC 51973 isolated in Norway from clinical specimens of harbor seal (Phoca vitulina), revealing interesting genes related to possible virulence factors. PMID:26586875

  17. Altered Composition of Ralstonia eutropha Poly(hydroxyalkanoate) through Expression of PHA Synthase from Allochromatium vinosum ATCC 35206

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The class III poly(hydroxyalkanoate) synthase (PHAS) genes (phaC and phaE) of a photosynthetic bacterium, Allochromatium vinosum ATCC 35206, were cloned, sequenced and expressed in a heterologous host. We employed a PCR technique coupled with a chromosomal gene-walking method to clone and subsequen...

  18. Construction of expression vectors for metabolic engineering of the vanillin-producing actinomycete Amycolatopsis sp. ATCC 39116.

    PubMed

    Fleige, Christian; Steinbüchel, Alexander

    2014-01-01

    Amycolatopsis sp. ATCC 39116 is able to synthesize the important flavoring agent vanillin from cheap natural substrates. The bacterium is therefore of great interest for the industry and used for the fermentative production of vanillin. In order to improve the production of natural vanillin with Amycolatopsis sp. ATCC 39116, the strain has been genetically engineered to optimize the metabolic flux towards the desired product. Extensive metabolic engineering was hitherto hampered, due to the lack of genetic tools like functional promoters and expression vectors. In this study, we report the establishment of a plasmid-based gene expression system for Amycolatopsis sp. ATCC 39116 that allows a further manipulation of the genotype. Four new Escherichia coli-Amycolatopsis shuttle vectors harboring different promoter elements were constructed, and the functionality of these regulatory elements was proven by the expression of the reporter gene gusA, encoding a β-glucuronidase. Glucuronidase activity was detected in all plasmid-harboring strains, and remarkable differences in the expression strength of the reporter gene depending on the used promoter were observed. The new expression vectors will promote the further genetic engineering of Amycolatopsis sp. ATCC 39116 to get insight into the metabolic network and to improve the strain for a more efficient industrial use. PMID:24743982

  19. Complete Genome Sequence of Gluconacetobacter hansenii Strain NQ5 (ATCC 53582), an Efficient Producer of Bacterial Cellulose.

    PubMed

    Pfeffer, Sarah; Mehta, Kalpa; Brown, R Malcolm

    2016-01-01

    This study reports the release of the complete nucleotide sequence of Gluconacetobacter hansenii strain NQ5 (ATCC 53582). This strain was isolated by R. Malcolm Brown, Jr. in a sugar mill in North Queensland, Australia, and is an efficient producer of bacterial cellulose. The elucidation of the genome will contribute to the study of the molecular mechanisms necessary for cellulose biosynthesis. PMID:27516505

  20. Effect of Lactobacillus brevis ATCC 8287 as a feeding supplement on the performance and immune function of piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lactobacillus brevis ATCC 8287, a surface (S-layer) strain, possesses a variety of functional properties that make it both a potential probiotic and a good vaccine vector candidate. With this in mind, our aim was to study the survival of L. brevis in the porcine gut and investigate the effect of th...

  1. Complete genome sequence of Streptomyces venezuelae ATCC 15439, a promising cell factory for production of secondary metabolites.

    PubMed

    Song, Ju Yeon; Yoo, Young Ji; Lim, Si-Kyu; Cha, Sun Ho; Kim, Ji-Eun; Roe, Jung-Hye; Kim, Jihyun F; Yoon, Yeo Joon

    2016-02-10

    Streptomyces venezuelae ATCC 15439, which produces 12- and 14-membered ring macrolide antibiotics, is a platform strain for heterologous expression of secondary metabolites. Its 9.05-Mb genome sequence revealed an abundance of genes involved in the biosynthesis of secondary metabolites and their precursors, which should be useful for the production of bioactive compounds. PMID:26718561

  2. Ca2+-Citrate Uptake and Metabolism in Lactobacillus casei ATCC 334

    PubMed Central

    Mortera, Pablo; Pudlik, Agata; Magni, Christian; Alarcón, Sergio

    2013-01-01

    The putative citrate metabolic pathway in Lactobacillus casei ATCC 334 consists of the transporter CitH, a proton symporter of the citrate-divalent metal ion family of transporters CitMHS, citrate lyase, and the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Resting cells of Lactobacillus casei ATCC 334 metabolized citrate in complex with Ca2+ and not as free citrate or the Mg2+-citrate complex, thereby identifying Ca2+-citrate as the substrate of the transporter CitH. The pathway was induced in the presence of Ca2+ and citrate during growth and repressed by the presence of glucose and of galactose, most likely by a carbon catabolite repression mechanism. The end products of Ca2+-citrate metabolism by resting cells of Lb. casei were pyruvate, acetate, and acetoin, demonstrating the activity of the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Following pyruvate, the pathway splits into two branches. One branch is the classical citrate fermentation pathway producing acetoin by α-acetolactate synthase and α-acetolactate decarboxylase. The other branch yields acetate, for which the route is still obscure. Ca2+-citrate metabolism in a modified MRS medium lacking a carbohydrate did not significantly affect the growth characteristics, and generation of metabolic energy in the form of proton motive force (PMF) was not observed in resting cells. In contrast, carbohydrate/Ca2+-citrate cometabolism resulted in a higher biomass yield in batch culture. However, also with these cells, no generation of PMF was associated with Ca2+-citrate metabolism. It is concluded that citrate metabolism in Lb. casei is beneficial when it counteracts acidification by carbohydrate metabolism in later growth stages. PMID:23709502

  3. Ca2+-citrate uptake and metabolism in Lactobacillus casei ATCC 334.

    PubMed

    Mortera, Pablo; Pudlik, Agata; Magni, Christian; Alarcón, Sergio; Lolkema, Juke S

    2013-08-01

    The putative citrate metabolic pathway in Lactobacillus casei ATCC 334 consists of the transporter CitH, a proton symporter of the citrate-divalent metal ion family of transporters CitMHS, citrate lyase, and the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Resting cells of Lactobacillus casei ATCC 334 metabolized citrate in complex with Ca(2+) and not as free citrate or the Mg(2+)-citrate complex, thereby identifying Ca(2+)-citrate as the substrate of the transporter CitH. The pathway was induced in the presence of Ca(2+) and citrate during growth and repressed by the presence of glucose and of galactose, most likely by a carbon catabolite repression mechanism. The end products of Ca(2+)-citrate metabolism by resting cells of Lb. casei were pyruvate, acetate, and acetoin, demonstrating the activity of the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Following pyruvate, the pathway splits into two branches. One branch is the classical citrate fermentation pathway producing acetoin by α-acetolactate synthase and α-acetolactate decarboxylase. The other branch yields acetate, for which the route is still obscure. Ca(2+)-citrate metabolism in a modified MRS medium lacking a carbohydrate did not significantly affect the growth characteristics, and generation of metabolic energy in the form of proton motive force (PMF) was not observed in resting cells. In contrast, carbohydrate/Ca(2+)-citrate cometabolism resulted in a higher biomass yield in batch culture. However, also with these cells, no generation of PMF was associated with Ca(2+)-citrate metabolism. It is concluded that citrate metabolism in Lb. casei is beneficial when it counteracts acidification by carbohydrate metabolism in later growth stages. PMID:23709502

  4. Cloning and characterization of the genes encoding nitrilotriacetate monooxygenase of Chelatobacter heintzii ATCC 29600.

    PubMed Central

    Knobel, H R; Egli, T; van der Meer, J R

    1996-01-01

    A 6.2-kb DNA fragment containing the genes for the nitrilotriacetate (NTA) monooxygenase of Chelatobacter heintzii ATCC 29600 was cloned and characterized by DNA sequencing and expression studies. The nucleotide sequence contained three major open reading frames (ORFs). Two of the ORFs, which were oriented divergently with an intergenic region of 307 bp, could be assigned to the NTA monooxygenase components A and B. The predicted N-terminal amino acid sequences of these ORFs were identical with those determined for the purified components. We therefore named these genes ntaA (for component A of NTA monooxygenase) and ntaB (for component B). The ntaA and ntaB genes could be expressed in Escherichia coli DH5alpha, and the gene products were visualized after Western blotting (immunoblotting) and incubation with polyclonal antibodies against component A or B. By mixing overproduced NtaB from E. coli and purified component A from C. heintzii ATCC 29600, reconstitution of a functional NTA monooxygenase complex was possible. The deduced gene product of ntaA showed only significant homology to SoxA (involved in dibenzothiophene degradation) and to SnaA (involved in pristamycin synthesis); that of ntaB shared weak homologies in one domain with other NADH:flavine mononucleotide oxidoreductases. These homologies provide no conclusive answer as to the possible evolutionary origin of the NTA monooxygenase. The deduced gene product of the third ORF (ORF1) had homology in the N-terminal region with the GntR class of bacterial regulator proteins and therefore may encode a regulator protein, possibly involved in regulation of ntaA and ntaB expression. PMID:8892809

  5. Enhancement of linear gramicidin expression from Bacillus brevis ATCC 8185 by casein peptide.

    PubMed

    Nakai, Tomonori; Yamauchi, Daisuke; Kubota, Kou

    2005-04-01

    Bacillus brevis (Brevibacillus parabrevis) ATCC 8185 synthesizes two kinds of antibiotic peptides, cyclopeptide tyrocidine and linear gramicidin. The production of linear gramicidin can be induced by the standard method (using a skim milk medium for pre-culture and beef broth for the main culture) employed for the induction of tyrocidine. In this study, we tried to determine the optimal growth medium for B. brevis ATCC 8185 for synthesizing linear gramicidin. The yield of linear gramicidin produced by the standard method was 3.11 microg/ml. When beef broth was used both as the pre-medium and the main medium, the yield of the antibiotic was only 0.59 microg/ml. To confirm the influence of skim milk, the strain was grown in a 1% skim milk medium. As a result, the amount of linear gramicidin produced reached 20.3 microg/ml. These findings show the importance of skim milk in the production of linear gramicidin. In the skim milk medium, the cells produced an extracellular protease 2 h before the linear gramicidin was expressed. The 1% skim milk medium pretreated by this protease did not allow the induction of linear gramicidin into the cells, and protease activity was not detected in the supernatant of the culture. When the cells were cultivated in a 1% egg albumin medium, protease activity from the supernatant of the culture was detected, but production of linear gramicidin was not observed. Therefore, a 1% casein medium was used for production of linear gramicidin. As a result, the yield of linear gramicidin produced in the medium reached 6.69 microg/ml. We concluded that a digested product of the extracellular protease from casein enhances linear gramicidin production. PMID:15849407

  6. Meta-analysis: Lactobacillus reuteri strain DSM 17938 (and the original strain ATCC 55730) for treating acute gastroenteritis in children.

    PubMed

    Szajewska, H; Urbańska, M; Chmielewska, A; Weizman, Z; Shamir, R

    2014-09-01

    Lactobacillus reuteri ATCC 55730 has been shown to provide a moderate clinical effect in the treatment of acute gastroenteritis (AGE) in children. However, as the L. reuteri ATCC 55730 strain was found to carry potentially transferable resistance traits for tetracycline and lincomycin, it was replaced by a new strain, L. reuteri DSM 17938, without unwanted plasmid-borne antibiotic resistance. Bioequivalence of the two strains has been suggested. We aimed to systematically evaluate data on the effectiveness of L. reuteri DSM 17938 and the original strain, L. reuteri ATCC 55730, in the treatment of AGE in children. The Cochrane Library, MEDLINE, and EMBASE databases, reference lists, and abstract books of major scientific meetings were searched in August 2013, with no language restrictions, for relevant randomised controlled trials (RCTs). Two RCTs (n=196) that evaluated L. reuteri DSM 17938 and three RCTs (n=156) that evaluated L. reuteri ATCC 55730, which involved hospitalised children aged 3 to 60 months, met the inclusion criteria. Compared with placebo or no treatment, DSM 17938 significantly reduced the duration of diarrhoea (mean difference -32 h, 95% confidence interval (CI): -41 to -24) and increased the chance of cure on day 3 (relative risk: 3.5, 95% CI: 1.2 to 10.8, random effects model). Similar results were obtained with the original strain, L. reuteri ATCC 55730. In conclusion, in hospitalised children, use of both strains of L. reuteri reduced the duration of diarrhoea, and more children were cured within 3 days. Data from outpatients and countryspecific cost-effectiveness analyses are needed. Given the limited data and the methodological limitations of the included trials, the evidence should be viewed with caution. PMID:24463209

  7. In situ hydrogen, acetone, butanol, ethanol and microdiesel production by Clostridium acetobutylicum ATCC 824 from oleaginous fungal biomass.

    PubMed

    Hassan, Elhagag Ahmed; Abd-Alla, Mohamed Hemida; Bagy, Magdy Mohamed Khalil; Morsy, Fatthy Mohamed

    2015-08-01

    An in situ batch fermentation technique was employed for biohydrogen, acetone, butanol, ethanol and microdiesel production from oleaginous fungal biomass using the anaerobic fermentative bacterium Clostridium acetobutylicum ATCC 824. Oleaginous fungal Cunninghamella echinulata biomass which has ability to accumulate up to 71% cellular lipid was used as the substrate carbon source. The maximum cumulative hydrogen by C. acetobutylicum ATCC 824 from crude C. echinulata biomass was 260 ml H2 l(-1), hydrogen production efficiency was 0.32 mol H2 mole(-1) glucose and the hydrogen production rate was 5.2 ml H2 h(-1). Subsequently, the produced acids (acetic and butyric acids) during acidogenesis phase are re-utilized by ABE-producing clostridia and converted into acetone, butanol, and ethanol. The total ABE produced by C. acetobutylicum ATCC 824 during batch fermentation was 3.6 g l(-1) from crude fungal biomass including acetone (1.05 g l(-1)), butanol (2.19 g l(-1)) and ethanol (0.36 g l(-1)). C. acetobutylicum ATCC 824 has ability to produce lipolytic enzymes with a specific activity 5.59 U/mg protein to hydrolyze ester containing substrates. The lipolytic potential of C. acetobutylicum ATCC 824 was used as a biocatalyst for a lipase transesterification process using the produced ethanol from ABE fermentation for microdiesel production. The fatty acid ethyl esters (microdiesel) generated from the lipase transesterification of crude C. echinulata dry mass was analyzed by GC/MS as 15.4% of total FAEEs. The gross energy content of biohydrogen, acetone, butanol, ethanol and biodiesel generated through C. acetobutylicum fermentation from crude C. echinulata dry mass was 3113.14 kJ mol(-1). These results suggest a possibility of integrating biohydrogen, acetone, butanol and ethanol production technology by C. acetobutylicum with microdiesel production from crude C. echinulata dry mass and therefore improve the feasibility and commercialization of bioenergy production. PMID

  8. Investigation of the Amycolatopsis sp. Strain ATCC 39116 Vanillin Dehydrogenase and Its Impact on the Biotechnical Production of Vanillin

    PubMed Central

    Fleige, Christian; Hansen, Gunda; Kroll, Jens

    2013-01-01

    The actinomycete Amycolatopsis sp. strain ATCC 39116 is capable of synthesizing large amounts of vanillin from ferulic acid, which is a natural cell wall component of higher plants. The desired intermediate vanillin is subject to undesired catabolism caused by the metabolic activity of a hitherto unknown vanillin dehydrogenase (VDHATCC 39116). In order to prevent the oxidation of vanillin to vanillic acid and thereby to obtain higher yields and concentrations of vanillin, the responsible vanillin dehydrogenase in Amycolatopsis sp. ATCC 39116 was investigated for the first time by using data from our genome sequence analysis and further bioinformatic approaches. The vdh gene was heterologously expressed in Escherichia coli, and the encoded vanillin dehydrogenase was characterized in detail. VDHATCC 39116 was purified to apparent electrophoretic homogeneity and exhibited NAD+-dependent activity toward vanillin, coniferylaldehyde, cinnamaldehyde, and benzaldehyde. The enzyme showed its highest level of activity toward vanillin at pH 8.0 and at a temperature of 44°C. In a next step, a precise vdh deletion mutant of Amycolatopsis sp. ATCC 39116 was generated. The mutant lost its ability to grow on vanillin and did not show vanillin dehydrogenase activity. A 2.3-times-higher vanillin concentration and a substantially reduced amount of vanillic acid occurred with the Amycolatopsis sp. ATCC 39116 Δvdh::Kmr mutant when ferulic acid was provided for biotransformation in a cultivation experiment on a 2-liter-bioreactor scale. Based on these results and taking further metabolic engineering into account, the Amycolatopsis sp. ATCC 39116 Δvdh::Kmr mutant represents an optimized and industrially applicable platform for the biotechnological production of natural vanillin. PMID:23064333

  9. Heterologous expression of endo-beta-1,4-D-glucanase from Clostridium cellulovorans in Clostridium acetobutylicum ATCC 824 following transformation of the engB gene.

    PubMed Central

    Kim, A Y; Attwood, G T; Holt, S M; White, B A; Blaschek, H P

    1994-01-01

    Heterologous expression of the Clostridium cellulovorans engB gene by Clostridium acetobutylicum BKW-1 was detected as zones of hydrolysis on carboxymethyl cellulose (CMC) Trypticase glucose yeast plates stained with Congo red. The extracellular cellulase preparation from C. acetobutylicum BKW-1 has a specific activity towards CMC which is more than fourfold that present in C. acetobutylicum ATCC 824. Western blot (immunoblot) analysis using the C. cellulovorans anti-EngB primary antibody demonstrated that an additional 44-kDa protein band was present in the supernatant derived from C. acetobutylicum BKW-1 but was not present in ATCC 824 or ATCC 824(pMTL500E). Images PMID:8117087

  10. Effects of Arsenite Resistance on the Growth and Functional Gene Expression of Leptospirillum ferriphilum and Acidithiobacillus thiooxidans in Pure Culture and Coculture

    PubMed Central

    Jiang, Huidan; Liang, Yili; Yin, Huaqun; Xiao, Yunhua; Guo, Xue; Xu, Ying; Hu, Qi; Liu, Hongwei; Liu, Xueduan

    2015-01-01

    The response of iron-oxidizing Leptospirillum ferriphilum YSK and sulfur-oxidizing Acidithiobacillus thiooxidans A01 to arsenite under pure culture and coculture was investigated based on biochemical characterization (concentration of iron ion and pH value) and related gene expression. L. ferriphilum YSK and At. thiooxidans A01 in pure culture could adapt up to 400 mM and 800 mM As(III) after domestication, respectively, although arsenite showed a negative effect on both strains. The coculture showed a stronger sulfur and ferrous ion oxidation activity when exposed to arsenite. In coculture, the pH value showed no significant difference when under 500 mM arsenite stress, and the cell number of At. thiooxidans was higher than that in pure culture benefiting from the interaction with L. ferriphilum. The expression profile showed that the arsenic efflux system in the coculture was more active than that in pure culture, indicating that there is a synergetic interaction between At. thiooxidans A01 and L. ferriphilum YSK. In addition, a model was proposed to illustrate the interaction between arsenite and the ars operon in L. ferriphilum YSK and At. thiooxidans A01. This study will facilitate the effective application of coculture in the bioleaching process by taking advantage of strain-strain communication and coordination. PMID:26064886

  11. Effects of inhibitors and NaCl on the oxidation of reduced inorganic sulfur compounds by a marine acidophilic, sulfur-oxidizing bacterium, Acidithiobacillus thiooxidans strain SH.

    PubMed

    Kamimura, Kazuo; Higashino, Emi; Kanao, Tadayoshi; Sugio, Tsuyoshi

    2005-02-01

    The effect of NaCl and the pathways of the oxidation of reduced inorganic sulfur compounds were studied using resting cells and cell-free extracts of Acidithiobacillus thiooxidans strain SH. This isolate specifically requires NaCl for growth. The oxidation of sulfur and sulfite by resting cells was strongly inhibited by 2-heptyl-4-hydroxyquinoline-N-oxide. Carbonylcyanide m-chlorophenyl-hydrazone and monensin were also relatively strong inhibitors. Thiosulfate-oxidizing activity was not inhibited by these uncouplers. Valinomycin did not inhibit the oxidation of sulfur compounds. NaCl stimulated the sulfur- and sulfite-oxidizing activities in resting cells but not in cell-free extracts. The tetrathionate-oxidizing activity in resting cells was slightly stimulated by NaCl, whereas it did not influence the thiosulfate-oxidizing activity. Sulfide oxidation was biphasic, suggesting the formation of intermediate sulfur. The initial phase of sulfide oxidation was not affected by NaCl, whereas the subsequent oxidation of sulfur in the second phase was Na+-dependent. A model is proposed for the role of NaCl in the metabolism of reduced sulfur compounds in A. thiooxidans strain SH. PMID:15375674

  12. Presence of a Family of Plasmids (29 to 65 Kilobases) with a 26-Kilobase Common Region in Different Strains of the Sulfur-Oxidizing Bacterium Acidithiobacillus caldus▿ †

    PubMed Central

    van Zyl, Leonard J.; Deane, Shelly M.; Louw, Lilly-Ann; Rawlings, Douglas E.

    2008-01-01

    Three large cryptic plasmids from different isolates of Acidithiobacillus caldus were rescued by using an in vitro transposition system that delivers a kanamycin-selectable marker and an Escherichia coli plasmid origin of replication. The largest of the plasmids, the 65-kb plasmid pTcM1, was isolated from a South African A. caldus strain, MNG. This plasmid was sequenced and compared to that of pTcF1 (39 kb, from strain “f,” South Africa) and pC-SH12 (29 kb, from strain C-SH12, Australia). With the exception of a 2.7-kb insertion sequence, pC-SH12 appears to represent the DNA common to all three plasmids and includes a number of accessory genes plus the plasmid “backbone” containing the replication region. The two larger plasmids carry, in addition, a number of insertion sequences of the ISL3 family and a composite transposon related to the Tn21 subfamily containing a highly mosaic region within the borders of the inverted repeats. Genes coding for arsenic resistance, plasmid mobilization, plasmid stability, and a putative restriction-modification system occur within these mosaic regions. PMID:18515486

  13. Effects of Arsenite Resistance on the Growth and Functional Gene Expression of Leptospirillum ferriphilum and Acidithiobacillus thiooxidans in Pure Culture and Coculture.

    PubMed

    Jiang, Huidan; Liang, Yili; Yin, Huaqun; Xiao, Yunhua; Guo, Xue; Xu, Ying; Hu, Qi; Liu, Hongwei; Liu, Xueduan

    2015-01-01

    The response of iron-oxidizing Leptospirillum ferriphilum YSK and sulfur-oxidizing Acidithiobacillus thiooxidans A01 to arsenite under pure culture and coculture was investigated based on biochemical characterization (concentration of iron ion and pH value) and related gene expression. L. ferriphilum YSK and At. thiooxidans A01 in pure culture could adapt up to 400 mM and 800 mM As(III) after domestication, respectively, although arsenite showed a negative effect on both strains. The coculture showed a stronger sulfur and ferrous ion oxidation activity when exposed to arsenite. In coculture, the pH value showed no significant difference when under 500 mM arsenite stress, and the cell number of At. thiooxidans was higher than that in pure culture benefiting from the interaction with L. ferriphilum. The expression profile showed that the arsenic efflux system in the coculture was more active than that in pure culture, indicating that there is a synergetic interaction between At. thiooxidans A01 and L. ferriphilum YSK. In addition, a model was proposed to illustrate the interaction between arsenite and the ars operon in L. ferriphilum YSK and At. thiooxidans A01. This study will facilitate the effective application of coculture in the bioleaching process by taking advantage of strain-strain communication and coordination. PMID:26064886

  14. Enhanced Cr bioleaching efficiency from tannery sludge with coinoculation of Acidithiobacillus thiooxidans TS6 and Brettanomyces B65 in an air-lift reactor.

    PubMed

    Fang, Di; Zhou, Li-Xiang

    2007-09-01

    Bioleaching process has been demonstrated to be an effective technology in removing Cr from tannery sludge, but a large quantity of dissolved organic matter (DOM) present in tannery sludge often exhibits a marked toxicity to chemolithoautotrophic bioleaching bacteria such as Acidithiobacillus thiooxidans. The purpose of the present study was therefore to enhance Cr bioleaching efficiencies through introducing sludge DOM-degrading heterotrophic microorganism into the sulfur-based sludge bioleaching system. An acid-tolerant DOM-degrading yeast strain Brettanomyces B65 was successfully isolated from a local Haining tannery sludge and it could metabolize sludge DOM as a source of energy and carbon for growth. A combined bioleaching experiment (coupling Brettanomyces B65 and A. thiooxidans TS6) performed in an air-lift reactor indicated that the rates of sludge pH reduction and ORP increase were greatly improved, resulting in enhanced Cr solubilization. Compared with the 5 days required for maximum solubilization of Cr for the control (single bioleaching process without inoculation of Brettanomyces B65), the bioleaching period was significantly shorten to 3 days for the combined bioleaching system. Moreover, little nitrogen and phosphorous were lost and the content of Cr was below the permitted levels for land application after 3 days of bioleaching treatment. PMID:17537479

  15. Two Master Switch Regulators Trigger A40926 Biosynthesis in Nonomuraea sp. Strain ATCC 39727

    PubMed Central

    Lo Grasso, Letizia; Maffioli, Sonia; Sosio, Margherita; Bibb, Mervyn; Puglia, Anna Maria

    2015-01-01

    ABSTRACT The actinomycete Nonomuraea sp. strain ATCC 39727 produces the glycopeptide A40926, the precursor of dalbavancin. Biosynthesis of A40926 is encoded by the dbv gene cluster, which contains 37 protein-coding sequences that participate in antibiotic biosynthesis, regulation, immunity, and export. In addition to the positive regulatory protein Dbv4, the A40926-biosynthetic gene cluster encodes two additional putative regulators, Dbv3 and Dbv6. Independent mutations in these genes, combined with bioassays and liquid chromatography-mass spectrometry (LC-MS) analyses, demonstrated that Dbv3 and Dbv4 are both required for antibiotic production, while inactivation of dbv6 had no effect. In addition, overexpression of dbv3 led to higher levels of A40926 production. Transcriptional and quantitative reverse transcription (RT)-PCR analyses showed that Dbv4 is essential for the transcription of two operons, dbv14-dbv8 and dbv30-dbv35, while Dbv3 positively controls the expression of four monocistronic transcription units (dbv4, dbv29, dbv36, and dbv37) and of six operons (dbv2-dbv1, dbv14-dbv8, dbv17-dbv15, dbv21-dbv20, dbv24-dbv28, and dbv30-dbv35). We propose a complex and coordinated model of regulation in which Dbv3 directly or indirectly activates transcription of dbv4 and controls biosynthesis of 4-hydroxyphenylglycine and the heptapeptide backbone, A40926 export, and some tailoring reactions (mannosylation and hexose oxidation), while Dbv4 directly regulates biosynthesis of 3,5-dihydroxyphenylglycine and other tailoring reactions, including the four cross-links, halogenation, glycosylation, and acylation. IMPORTANCE This report expands knowledge of the regulatory mechanisms used to control the biosynthesis of the glycopeptide antibiotic A40926 in the actinomycete Nonomuraea sp. strain ATCC 39727. A40926 is the precursor of dalbavancin, approved for treatment of skin infections by Gram-positive bacteria. Therefore, understanding the regulation of its biosynthesis

  16. Azotobacter Genomes: The Genome of Azotobacter chroococcum NCIMB 8003 (ATCC 4412)

    PubMed Central

    Robson, Robert L.; Jones, Robert; Robson, R. Moyra; Schwartz, Ariel; Richardson, Toby H.

    2015-01-01

    The genome of the soil-dwelling heterotrophic N2-fixing Gram-negative bacterium Azotobacter chroococcum NCIMB 8003 (ATCC 4412) (Ac-8003) has been determined. It consists of 7 circular replicons totalling 5,192,291 bp comprising a circular chromosome of 4,591,803 bp and six plasmids pAcX50a, b, c, d, e, f of 10,435 bp, 13,852, 62,783, 69,713, 132,724, and 311,724 bp respectively. The chromosome has a G+C content of 66.27% and the six plasmids have G+C contents of 58.1, 55.3, 56.7, 59.2, 61.9, and 62.6% respectively. The methylome has also been determined and 5 methylation motifs have been identified. The genome also contains a very high number of transposase/inactivated transposase genes from at least 12 of the 17 recognised insertion sequence families. The Ac-8003 genome has been compared with that of Azotobacter vinelandii ATCC BAA-1303 (Av-DJ), a derivative of strain O, the only other member of the Azotobacteraceae determined so far which has a single chromosome of 5,365,318 bp and no plasmids. The chromosomes show significant stretches of synteny throughout but also reveal a history of many deletion/insertion events. The Ac-8003 genome encodes 4628 predicted protein-encoding genes of which 568 (12.2%) are plasmid borne. 3048 (65%) of these show > 85% identity to the 5050 protein-encoding genes identified in Av-DJ, and of these 99 are plasmid-borne. The core biosynthetic and metabolic pathways and macromolecular architectures and machineries of these organisms appear largely conserved including genes for CO-dehydrogenase, formate dehydrogenase and a soluble NiFe-hydrogenase. The genetic bases for many of the detailed phenotypic differences reported for these organisms have also been identified. Also many other potential phenotypic differences have been uncovered. Properties endowed by the plasmids are described including the presence of an entire aerobic corrin synthesis pathway in pAcX50f and the presence of genes for retro-conjugation in pAcX50c. All these

  17. Actinoplanes teichomyceticus ATCC 31121 as a cell factory for producing teicoplanin

    PubMed Central

    2011-01-01

    Background Teicoplanin is a glycopeptide antibiotic used clinically in Europe and in Japan for the treatment of multi-resistant Gram-positive infections. It is produced by fermenting Actinoplanes teichomyceticus. The pharmaceutically active principle is teicoplanin A2, a complex of compounds designated T-A2-1-A2-5 differing in the length and branching of the fatty acid moiety linked to the glucosamine residue on the heptapeptide scaffold. According to European and Japanese Pharmacopoeia, components of the drug must be reproduced in fixed amounts to be authorized for clinical use. Results We report our studies on optimizing the fermentation process to produce teicoplanin A2 in A. teichomyceticus ATCC 31121. Robustness of the process was assessed on scales from a miniaturized deep-well microtiter system to flasks and 3-L bioreactor fermenters. The production of individual factors T-A2-1-A2-5 was modulated by adding suitable precursors to the cultivation medium. Specific production of T-A2-1, characterized by a linear C10:1 acyl moiety, is enhanced by adding methyl linoleate, trilinoleate, and crude oils such as corn and cottonseed oils. Accumulation of T-A2-3, characterized by a linear C10:0 acyl chain, is stimulated by adding methyl oleate, trioleate, and oils such as olive and lard oils. Percentages of T-A2-2, T-A2-4, and, T-A2-5 bearing the iso-C10:0, anteiso-C11:0, and iso-C11:0 acyl moieties, respectively, are significantly increased by adding precursor amino acids L-valine, L-isoleucine, and L-leucine. Along with the stimulatory effect on specific complex components, fatty acid esters, oils, and amino acids (with the exception of L-valine) inhibit total antibiotic productivity overall. By adding industrial oils to medium containing L-valine the total production is comparable, giving unusual complex compositions. Conclusions Since the cost and the quality of teicoplanin production depend mainly on the fermentation process, we developed a robust and scalable

  18. Structural analysis of Clostridium acetobutylicum ATCC 824 glycoside hydrolase from CAZy family GH105

    SciTech Connect

    Germane, Katherine L.; Servinsky, Matthew D.; Gerlach, Elliot S.; Sund, Christian J.; Hurley, Margaret M.

    2015-07-29

    The crystal structure of the protein product of the C. acetobutylicum ATCC 824 gene CA-C0359 is structurally similar to YteR, an unsaturated rhamnogalacturonyl hydrolase from B. subtilis strain 168. Substrate modeling and electrostatic studies of the active site of the structure of CA-C0359 suggests that the protein can now be considered to be part of CAZy glycoside hydrolase family 105. Clostridium acetobutylicum ATCC 824 gene CA-C0359 encodes a putative unsaturated rhamnogalacturonyl hydrolase (URH) with distant amino-acid sequence homology to YteR of Bacillus subtilis strain 168. YteR, like other URHs, has core structural homology to unsaturated glucuronyl hydrolases, but hydrolyzes the unsaturated disaccharide derivative of rhamnogalacturonan I. The crystal structure of the recombinant CA-C0359 protein was solved to 1.6 Å resolution by molecular replacement using the phase information of the previously reported structure of YteR (PDB entry (http://scripts.iucr.org/cgi-bin/cr.cgi?rm)) from Bacillus subtilis strain 168. The YteR-like protein is a six-α-hairpin barrel with two β-sheet strands and a small helix overlaying the end of the hairpins next to the active site. The protein has low primary protein sequence identity to YteR but is structurally similar. The two tertiary structures align with a root-mean-square deviation of 1.4 Å and contain a highly conserved active pocket. There is a conserved aspartic acid residue in both structures, which has been shown to be important for hydration of the C=C bond during the release of unsaturated galacturonic acid by YteR. A surface electrostatic potential comparison of CA-C0359 and proteins from CAZy families GH88 and GH105 reveals the make-up of the active site to be a combination of the unsaturated rhamnogalacturonyl hydrolase and the unsaturated glucuronyl hydrolase from Bacillus subtilis strain 168. Structural and electrostatic comparisons suggests that the protein may have a slightly different substrate

  19. The type strain of Lactobacillus casei is ATCC 393, ATCC 334 cannot serve as the type because it represents a different taxon, the name Lactobacillus paracasei and its subspecies names are not rejected and the revival of the name 'Lactobacillus zeae' contravenes Rules 51b (1) and (2) of the International Code of Nomenclature of Bacteria. Opinion 82.

    PubMed

    2008-07-01

    The Judicial Commission affirms that typification of Lactobacillus casei is based on ATCC 393, that ATCC 334 is a member of a different taxon and that the publication rejecting the name Lactobacillus paracasei (and its included subspecies) together with the revival of the name 'Lactobacillus zeae' contravenes Rules 51b (1) and (2) of the International Code of Nomenclature of Bacteria. PMID:18599731

  20. An ATP-grasp ligase involved in the last biosynthetic step of the iminomycosporine shinorine in Nostoc punctiforme ATCC 29133.

    PubMed

    Gao, Qunjie; Garcia-Pichel, Ferran

    2011-11-01

    We investigated the genetic basis for mycosporine sunscreen biosynthesis by the cyanobacterium Nostoc punctiforme ATCC 29133. Heterologous expression in Escherichia coli of three contiguous N. punctiforme genes (NpR5600, NpR5599, and NpR5598, here named mysA, mysB, and mysC, respectively) led to the production of mycosporine-glycine, an oxomycosporine. Additional expression of gene NpF5597 (mysD) led to the conversion of mycosporine-glycine into iminomycosporines (preferentially shinorine but also others like mycosporine-2-glycine and porphyra-334). This represents a new mode of enzymatic synthesis for iminomycosporines, one that differs in genetic origin, mechanism, and apparent substrate specificity from that known in Anabaena variabilis ATCC 29413. These results add to the emerging profile of the protein family of ATP-dependent ligases, to which the mysC product belongs, as important condensation enzymes in microbial secondary metabolism. PMID:21890703

  1. Isolation and characterisation of dipeptidyl peptidase IV from Prevotella loescheii ATCC 15930.

    PubMed

    Koreeda, Y; Hayakawa, M; Ikemi, T; Abiko, Y

    2001-08-01

    A proline-specific dipeptidyl aminopeptidase, dipeptidyl peptidase IV (EC 3.4.14.5), was purified from a cell sonicate soluble fraction of Prevotella loescheii ATCC 15930 by sequential column chromatography. The molecular mass of the native enzyme was estimated as 160 kDa by high-pressure liquid gel filtration column chromatography and unheated sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The subunit molecular mass was 80 kDa when the enzyme was heated to 100 degrees C in the presence of 2-mercaptoethanol before SDS-PAGE, suggesting that the native enzyme consists of two identical subunits and is folded in 2% SDS. The optimum pH, with glycyl-prolyl-4-methyl-coumaryl-7-amide as the substrate, was 8.0; the isoelectric point was 5.2. Purified enzyme showed a strong preference for dipeptide substrates containing proline and, less efficiently, alanine in the P1 position. The enzyme was markedly inhibited by Cd(2+), Zn(2+), Hg(2+), Co(2+), and serine proteinase inhibitor di-isopropylfluorophosphate. PMID:11389867

  2. Identification of galacto-N-biose phosphorylase from Clostridium perfringens ATCC13124.

    PubMed

    Nakajima, Masahiro; Nihira, Takanori; Nishimoto, Mamoru; Kitaoka, Motomitsu

    2008-03-01

    Lacto-N-biose phosphorylase (LNBP) from bifidobacteria is involved in the metabolism of lacto-N-biose I (Galbeta1-->3GlcNAc, LNB) and galacto-N-biose (Galbeta1-->3GalNAc, GNB). A homologous gene of LNBP (CPF0553 protein) was identified in the genome of Clostridium perfringens ATCC13124, which is a gram-positive anaerobic intestinal bacterium. In the present study, we cloned the gene and compared the substrate specificity of the CPF0553 protein with LNBP from Bifidobacterium longum JCM1217 (LNBPBl). In the presence of alpha-galactose 1-phosphate (Gal 1-P) as a donor, the CPF0553 protein acted only on GlcNAc and GalNAc, and GalNAc was a more effective acceptor than GlcNAc. The reaction product from GlcNAc/GalNAc and Gal 1-P was identified as LNB or GNB. The CPF0553 protein also phosphorolyzed GNB much faster than LNB, which suggests that the protein should be named galacto-N-biose phosphorylase (GNBP). GNBP showed a kcat/Km value for GNB that was approximately 50 times higher than that for LNB, whereas LNBPBl showed similar kcat/Km values for both GNB and LNB. Because C. perfringens possesses a gene coding endo-alpha-N-acetylgalactosaminidase, GNBP may play a role in the intestinal residence by metabolizing GNB that is available as a mucin core sugar. PMID:18183385

  3. Analysis of the mechanism and regulation of lactose transport and metabolism in Clostridium acetobutylicum ATCC 824.

    PubMed

    Yu, Yang; Tangney, Martin; Aass, Hans C; Mitchell, Wilfrid J

    2007-03-01

    Although the acetone-butanol-ethanol fermentation of Clostridium acetobutylicum is currently uneconomic, the ability of the bacterium to metabolize a wide range of carbohydrates offers the potential for revival based on the use of cheap, low-grade substrates. We have investigated the uptake and metabolism of lactose, the major sugar in industrial whey waste, by C. acetobutylicum ATCC 824. Lactose is taken up via a phosphoenolpyruvate-dependent phosphotransferase system (PTS) comprising both soluble and membrane-associated components, and the resulting phosphorylated derivative is hydrolyzed by a phospho-beta-galactosidase. These activities are induced during growth on lactose but are absent in glucose-grown cells. Analysis of the C. acetobutylicum genome sequence identified a gene system, lacRFEG, encoding a transcriptional regulator of the DeoR family, IIA and IICB components of a lactose PTS, and phospho-beta-galactosidase. During growth in medium containing both glucose and lactose, C. acetobutylicum exhibited a classical diauxic growth, and the lac operon was not expressed until glucose was exhausted from the medium. The presence upstream of lacR of a potential catabolite responsive element (cre) encompassing the transcriptional start site is indicative of the mechanism of carbon catabolite repression characteristic of low-GC gram-positive bacteria. A pathway for the uptake and metabolism of lactose by this industrially important organism is proposed. PMID:17209069

  4. Heterologous expression and localization of gentisate transporter Ncg12922 from Corynebacterium glutamicum ATCC 13032

    SciTech Connect

    Xu Ying; Yan Dazhong; Zhou Ningyi . E-mail: n.zhou@pentium.whiov.ac.cn

    2006-07-28

    Ralstonia sp. strain U2 metabolizes naphthalene via gentisate (2,5-dihydroxybenzoate) to central metabolites, but it was found unable to utilize gentisate as growth substrate. A putative gentisate transporter encoded by ncg12922 from Corynebacterium glutamicum ATCC 13032 was functionally expressed in Ralstonia sp. strain U2, converting strain U2 to a gentisate utilizer. After ncg12922 was inserted into plasmid pGFPe with green fluorescence protein gene gfp, the expressed fusion protein Ncg12922-GFP could be visualized in the periphery of Escherichia coli cells under confocal microscope, consistent with a cytoplasmic membrane location. In contrast, GFP was ubiquitous in the cytoplasm of E. coli cells carrying pGFPe only. Gentisate 1,2-dioxygenase activity was present in the cell extract from strain U2 induced with gentisate but at a much lower level (one-fifth) than that obtained with salicylate. However, it exhibited a similar level in strain U2 containing Ncg12922 induced either by salicylate or gentisate.

  5. Metabolic engineering of Corynebacterium glutamicum ATCC13032 to produce S-adenosyl-L-methionine.

    PubMed

    Han, Guoqiang; Hu, Xiaoqing; Qin, Tianyu; Li, Ye; Wang, Xiaoyuan

    2016-02-01

    As an important biological methyl group donor, S-adenosyl-L-methionine is used as nutritional supplement or drug for various diseases, but bacterial strains that can efficiently produce S-adenosyl-L-methionine are not available. In this study, Corynebacterium glutamicum strain HW104 which can accumulate S-adenosyl-L-methionine was constructed from C. glutamicum ATCC13032 by deleting four genes thrB, metB, mcbR and Ncgl2640, and six genes metK, vgb, lysC(m), hom(m), metX and metY were overexpressed in HW104 in different combinations, forming strains HW104/pJYW-4-metK-vgb, HW104/pJYW-4-SAM2C-vgb, HW104/pJYW-4-metK-vgb-metYX, and HW104/pJYW-4-metK-vgb-metYX-hom(m)-lysC(m). Fermentation experiments showed that HW104/pJYW-4-metK-vgb produced more S-adenosyl-L-methionine than other strains, and the yield achieved 196.7 mg/L (12.15 mg/g DCW) after 48h. The results demonstrate the potential application of C. glutamicum for production of S-adenosyl-L-methionine without addition of L-methionine. PMID:26777246

  6. Biosurfactant Production by Cultivation of Bacillus atrophaeus ATCC 9372 in Semidefined Glucose/Casein-Based Media

    NASA Astrophysics Data System (ADS)

    Das Neves, Luiz Carlos Martins; de Oliveira, Kátia Silva; Kobayashi, Márcio Junji; Vessoni Penna, Thereza Christina; Converti, Attilio

    Biosurfactants are proteins with detergent, emulsifier, and antimicrobial actions that have potential application in environmental applications such as the treatment of organic pollutants and oil recovery. Bacillus atrophaeus strains are nonpathogenic and are suitable source of biosurfactants, among which is surfactin. The aim of this work is to establish a culture medium composition able to stimulate biosurfactants production by B. atrophaeus ATCC 9372. Batch cultivations were carried out in a rotary shaker at 150 rpm and 35°C for 24 h on glucose- and/or casein-based semidefined culture media also containing sodium chloride, dibasic sodium phosphate, and soy flour. The addition of 14.0 g/L glucose in a culture medium containing 10.0 g/L of casein resulted in 17 times higher biosurfactant production (B max=635.0 mg/L). Besides, the simultaneous presence of digested casein (10.0 g/L), digested soy flour (3.0 g/L), and glucose (18.0 g/L) in the medium was responsible for a diauxic effect during cell growth. Once the diauxie started, the average biosurfactants concentration was 16.8% less than that observed before this phenomenon. The capability of B. atrophaeus strain to adapt its own metabolism to use several nutrients as energy sources and to preserve high levels of biosurfactants in the medium during the stationary phase is a promising feature for its possible application in biological treatments.

  7. Production of Surfactant from Bacillus subtilis ATCC 21332 using Potato substrates

    SciTech Connect

    Fox, Sandra Lynn; Bala, Greg Alan

    2000-12-01

    Surfactin, a lipopeptide biosurfactant, produced by Bacillus subtilis is known to reduce the surface tension of water from 72 to 27 mN/m. Potato substrates were evaluated as a carbon source for surfactant production by B. subtilis ATCC 21332. An established potato medium, simulated liquid and solid potato waste media, and a commercially prepared potato starch in a mineral salts medium were evaluated in shake flask experiments to verify growth, surface tension reduction, and carbohydrate reduction capabilities. Total carbohydrate assays and glucose monitoring indicated that B. subtilis was able to degrade potato substrates to produce surfactant. Surface tensions dropped from 71.3±0.1 to 28.3±0.3 mN/m (simulated solid potato medium) and to 27.5±0.3 mN/m (mineral salts medium). A critical micelle concentration (CMC) of 0.10 g/l was obtained from a methylene chloride extract of the simulated solid potato medium.

  8. A novel meta-cleavage product hydrolase from Flavobacterium sp. ATCC27551

    SciTech Connect

    Khajamohiddin, Syed; Babu, Pakala Suresh; Chakka, Deviprasanna; Merrick, Mike; Bhaduri, Anirban; Sowdhamini, Ramanathan; Siddavattam, Dayananda . E-mail: sdsl@uohyd.ernet.in

    2006-12-22

    The organophosphate degrading (opd) gene cluster of plasmid pPDL2 of Flavobacterium sp. ATCC27551 contains a novel open-reading frame, orf243. This was predicted to encode an {alpha}/{beta} hydrolase distantly related to the meta-fission product (MFP) hydrolases such as XylF, PhnD, and CumD. By homology modeling Orf243 has most of the structural features of MFP hydrolases including the characteristic active site catalytic triad. The purified protein (designated MfhA) is a homotetramer and shows similar affinity for 2-hydroxy-6-oxohepta-2,4-dienoate (HOHD), 2-hydroxymuconic semialdehyde (HMSA), and 2-hydroxy-5-methylmuconic semialdehyde (HMMSA), the meta-fission products of 3-methyl catechol, catechol, and 4-methyl catechol. The unique catalytic properties of MfhA and the presence near its structural gene of cis-elements required for transposition suggest that mfhA has evolved towards encoding a common hydrolase that can act on meta-fission products containing either aldehyde or ketone groups.

  9. Bismuth(III) deferiprone effectively inhibits growth of Desulfovibrio desulfuricans ATCC 27774.

    PubMed

    Barton, Larry L; Lyle, Daniel A; Ritz, Nathaniel L; Granat, Alex S; Khurshid, Ali N; Kherbik, Nada; Hider, Robert; Lin, Henry C

    2016-04-01

    Sulfate-reducing bacteria have been implicated in inflammatory bowel diseases and ulcerative colitis in humans and there is an interest in inhibiting the growth of these sulfide-producing bacteria. This research explores the use of several chelators of bismuth to determine the most effective chelator to inhibit the growth of sulfate-reducing bacteria. For our studies, Desulfovibrio desulfuricans ATCC 27774 was grown with nitrate as the electron acceptor and chelated bismuth compounds were added to test for inhibition of growth. Varying levels of inhibition were attributed to bismuth chelated with subsalicylate or citrate but the most effective inhibition of growth by D. desulfuricans was with bismuth chelated by deferiprone, 3-hydroxy-1,2-dimethyl-4(1H)-pyridone. Growth of D. desulfuricans was inhibited by 10 μM bismuth as deferiprone:bismuth with either nitrate or sulfate respiration. Our studies indicate deferiprone:bismuth has bacteriostatic activity on D. desulfuricans because the inhibition can be reversed following exposure to 1 mM bismuth for 1 h at 32 °C. We suggest that deferiprone is an appropriate chelator for bismuth to control growth of sulfate-reducing bacteria because deferiprone is relatively nontoxic to animals, including humans, and has been used for many years to bind Fe(III) in the treatment of β-thalassemia. PMID:26896170

  10. Biosurfactant-mediated biodegradation of straight and methyl-branched alkanes by Pseudomonas aeruginosa ATCC 55925

    PubMed Central

    2011-01-01

    Accidental oil spills and waste disposal are important sources for environmental pollution. We investigated the biodegradation of alkanes by Pseudomonas aeruginosa ATCC 55925 in relation to a rhamnolipid surfactant produced by the same bacterial strain. Results showed that the linear C11-C21 compounds in a heating oil sample degraded from 6% to 100%, whereas the iso-alkanes tended to be recalcitrant unless they were exposed to the biosurfactant; under such condition total biodegradation was achieved. Only the biodegradation of the commercial C12-C19 alkanes could be demonstrated, ranging from 23% to 100%, depending on the experimental conditions. Pristane (a C19 branched alkane) only biodegraded when present alone with the biosurfactant and when included in an artificial mixture even without the biosurfactant. In all cases the biosurfactant significantly enhanced biodegradation. The electron scanning microscopy showed that cells depicted several adaptations to growth on hydrocarbons, such as biopolymeric spheres with embedded cells distributed over different layers on the spherical surfaces and cells linked to each other by extracellular appendages. Electron transmission microscopy revealed transparent inclusions, which were associated with hydrocarbon based-culture cells. These patterns of hydrocarbon biodegradation and cell adaptations depended on the substrate bioavailability, type and length of hydrocarbon. PMID:21906343

  11. Proteome data to explore the impact of pBClin15 on Bacillus cereus ATCC 14579.

    PubMed

    Madeira, Jean-Paul; Alpha-Bazin, Béatrice; Armengaud, Jean; Omer, Hélène; Duport, Catherine

    2016-09-01

    This data article reports changes in the cellular and exoproteome of B. cereus cured from pBClin15.Time-course changes of proteins were assessed by high-throughput nanoLC-MS/MS. We report all the peptides and proteins identified and quantified in B. cereus with and without pBClin15. Proteins were classified into functional groups using the information available in the KEGG classification and we reported their abundance in term of normalized spectral abundance factor. The repertoire of experimentally confirmed proteins of B. cereus presented here is the largest ever reported, and provides new insights into the interplay between pBClin15 and its host B. cereus ATCC 14579. The data reported here is related to a published shotgun proteomics analysis regarding the role of pBClin15, "Deciphering the interactions between the Bacillus cereus linear plasmid, pBClin15, and its host by high-throughput comparative proteomics" Madeira et al. [1]. All the associated mass spectrometry data have been deposited in the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org) via the PRIDE partner repository (http://www.ebi.ac.uk/pride/), with the dataset identifier PRIDE: PXD001568, PRIDE: PXD002788 and PRIDE: PXD002789. PMID:27547804

  12. SpoIIE Regulates Sporulation but Does Not Directly Affect Solventogenesis in Clostridium acetobutylicum ATCC 824

    PubMed Central

    Scotcher, Miles C.; Bennett, George N.

    2005-01-01

    Using gene expression reporter vectors, we examined the activity of the spoIIE promoter in wild-type and spo0A-deleted strains of Clostridium acetobutylicum ATCC 824. In wild-type cells, the spoIIE promoter is active in a transient manner during late solventogenesis, but in strain SKO1, where the sporulation initiator spo0A is disrupted, no spoIIE promoter activity is detectable at any stage of growth. Strains 824(pMSpo) and 824(pASspo) were created to overexpress spoIIE and to decrease spoIIE expression via antisense RNA targeted against spoIIE, respectively. Some cultures of strains 824(pMSpo) degenerated during fermentations by losing the pSOL1 megaplasmid and hence did not produce the solvents ethanol, acetone, and butanol. The frequent degeneration event was shown to require an intact copy of spoIIE. Nondegenerate cultures of 824(pMSpo) exhibited normal growth and solvent production. Strain 824(pASspo) exhibited prolonged solventogenesis characterized by increased production of ethanol (225%), acetone (43%), and butanol (110%). Sporulation in strains harboring pASspo was significantly delayed, with sporulating cells exhibiting altered morphology. These results suggest that SpoIIE has no direct effect on the control of solventogenesis and that the changes in solvent production in spoIIE-downregulated cells are mediated by effects on the cell during sporulation. PMID:15743939

  13. Metabolic Engineering of Clostridium acetobutylicum ATCC 824 for Isopropanol-Butanol-Ethanol Fermentation

    PubMed Central

    Lee, Joungmin; Jang, Yu-Sin; Choi, Sung Jun; Im, Jung Ae; Song, Hyohak; Cho, Jung Hee; Seung, Do Young; Papoutsakis, E. Terry; Bennett, George N.

    2012-01-01

    Clostridium acetobutylicum naturally produces acetone as well as butanol and ethanol. Since acetone cannot be used as a biofuel, its production needs to be minimized or suppressed by cell or bioreactor engineering. Thus, there have been attempts to disrupt or inactivate the acetone formation pathway. Here we present another approach, namely, converting acetone to isopropanol by metabolic engineering. Since isopropanol can be used as a fuel additive, the mixture of isopropanol, butanol, and ethanol (IBE) produced by engineered C. acetobutylicum can be directly used as a biofuel. IBE production is achieved by the expression of a primary/secondary alcohol dehydrogenase gene from Clostridium beijerinckii NRRL B-593 (i.e., adhB-593) in C. acetobutylicum ATCC 824. To increase the total alcohol titer, a synthetic acetone operon (act operon; adc-ctfA-ctfB) was constructed and expressed to increase the flux toward isopropanol formation. When this engineering strategy was applied to the PJC4BK strain lacking in the buk gene (encoding butyrate kinase), a significantly higher titer and yield of IBE could be achieved. The resulting PJC4BK(pIPA3-Cm2) strain produced 20.4 g/liter of total alcohol. Fermentation could be prolonged by in situ removal of solvents by gas stripping, and 35.6 g/liter of the IBE mixture could be produced in 45 h. PMID:22210214

  14. Effect of Low Shear Modeled Microgravity (LSMMG) on the Probiotic Lactobacillus Acidophilus ATCC 4356

    NASA Technical Reports Server (NTRS)

    Stahl, S.; Voorhies, A.; Lorenzi, H.; Castro-Wallace, S.; Douglas, G.

    2016-01-01

    The introduction of generally recognized as safe (GRAS) probiotic microbes into the spaceflight food system has the potential for use as a safe, non-invasive, daily countermeasure to crew microbiome and immune dysregulation. However, the microgravity effects on the stress tolerances and genetic expression of probiotic bacteria must be determined to confirm translation of strain benefits and to identify potential for optimization of growth, survival, and strain selection for spaceflight. The work presented here demonstrates the translation of characteristics of a GRAS probiotic bacteria to a microgravity analog environment. Lactobacillus acidophilus ATCC 4356 was grown in the low shear modeled microgravity (LSMMG) orientation and the control orientation in the rotating wall vessel (RWV) to determine the effect of LSMMG on the growth, survival through stress challenge, and gene expression of the strain. No differences were observed between the LSMMG and control grown L. acidophilus, suggesting that the strain will behave similarly in spaceflight and may be expected to confer Earth-based benefits.

  15. Mutation of aspartic acid residues in the fructosyltransferase of Streptococcus salivarius ATCC 25975.

    PubMed Central

    Song, D D; Jacques, N A

    1999-01-01

    The site-directed mutated fructosyltransferases (Ftfs) of Streptococcus salivarius ATCC 25975, D312E, D312S, D312N and D312K were all active at 37 degrees C, indicating that Asp-312 present in the 'sucrose box' was not the nucleophilic Asp residue responsible for the formation of a covalent fructosyl-enzyme intermediate required for enzyme activity. Analysis of the kinetic constants of the purified mutated forms of the enzyme showed that Asp-312 was most likely an essential amino acid involved in determining acceptor recognition and/or stabilizing a beta-turn in the protein. In contrast, when the Asp-397 of the Ftf present in the conserved triplet RDP motif of all 60 bacterial and plant family-32 glycosylhydrolases was mutated to a Ser residue, both sucrose hydrolysis and polymerization ceased. Tryptophan emission spectra confirmed that this mutation did not alter protein structure. Comparison of published data from other site-directed mutated enzymes implicated the Asp residue in the RDP motif as the one that may form a transient covalent fructosyl intermediate during the catalysis of sucrose by the Ftf of S. salivarius. PMID:10548559

  16. Construction and Evaluation of a Clostridium thermocellum ATCC 27405 Whole-Genome Oligonucleotide Microarray

    NASA Astrophysics Data System (ADS)

    Brown, Steven D.; Raman, Babu; McKeown, Catherine K.; Kale, Shubha P.; He, Zhili; Mielenz, Jonathan R.

    Clostridium thermocellum is an anaerobic, thermophilic bacterium that can directly convert cellulosic substrates into ethanol. Microarray technology is a powerful tool to gain insights into cellular processes by examining gene expression under various physiological states. Oligonucleotide microarray probes were designed for 96.7% of the 3163 C. thermocellum ATCC 27405 candidate protein-encoding genes and then a partial-genome microarray containing 70 C. thermocellum specific probes was constructed and evaluated. We detected a signal-to-noise ratio of three with as little as 1.0 ng of genomic DNA and only low signals from negative control probes (nonclostridial DNA), indicating the probes were sensitive and specific. In order to further test the specificity of the array we amplified and hybridized 10 C. thermocellum polymerase chain reaction products that represented different genes and found gene specific hybridization in each case. We also constructed a whole-genome microarray and prepared total cellular RNA from the same point in early-logarithmic growth phase from two technical replicates during cellobiose fermentation. The reliability of the microarray data was assessed by cohybridization of labeled complementary DNA from the cellobiose fermentation samples and the pattern of hybridization revealed a linear correlation. These results taken together suggest that our oligonucleotide probe set can be used for sensitive and specific C. thermocellum transcriptomic studies in the future.

  17. Cloning, expression and characterization of a eukaryotic cycloalkanone monooxygenase from Cylindrocarpon radicicola ATCC 11011.

    PubMed

    Leipold, Friedemann; Wardenga, Rainer; Bornscheuer, Uwe T

    2012-05-01

    In this study, we have cloned and characterized a cycloalkanone monooxygenase (CAMO) from the ascomycete Cylindrocarpon radicicola ATCC 11011 (identical to Cylindrocarpon destructans DSM 837). The primary structure of this Baeyer-Villiger monooxygenase (BMVO) revealed 531 residues with around 45% sequence identity to known cyclohexanone monooxygenases. The enzyme was functionally overexpressed in Escherichia coli and investigated with respect to substrate spectrum and kinetic parameters. Substrate specificity studies revealed that a large variety of cycloaliphatic and bicycloaliphatic ketones are converted by this CAMO. A high catalytic efficiency against cyclobutanone was observed and seems to be a particular property of this BVMO. The thus produced butyrolactone derivatives are valuable building blocks for the synthesis of a variety of natural products and bioactive compounds. Furthermore, the enzyme revealed activity against open-chain ketones such as cyclobutyl, cyclopentyl and cyclohexyl methyl ketone which have not been reported to be accepted by typical cyclohexanone monooxygenases. These results suggest that the BVMO from C. radicicola indeed might be rather unique and since no BVMOs originating from eukaryotic organisms have been produced recombinantly so far, this study provides the first example for such an enzyme. PMID:22075635

  18. Modeling for Gellan Gum Production by Sphingomonas paucimobilis ATCC 31461 in a Simplified Medium

    PubMed Central

    Wang, Xia; Xu, Ping; Yuan, Yong; Liu, Changlong; Zhang, Dezhong; Yang, Zhengting; Yang, Chunyu; Ma, Cuiqing

    2006-01-01

    Gellan gum production was carried out by Sphingomonas paucimobilis ATCC 31461 in a simplified medium with a short incubation time, and a kinetic model for understanding, controlling, and optimizing the fermentation process was proposed. The results revealed that glucose was the best carbon source and that the optimal concentration was 30 g liter−1. As for the fermenting parameters, considerably large amounts of gellan gum were yielded by an 8-h-old culture and a 4% inoculum at 200 rpm on a rotary shaker. Under the optimized conditions, the maximum level of gellan gum (14.75 g liter−1) and the highest conversion efficiency (49.17%) were obtained in a 30-liter fermentor in batch fermentation. Logistic and Luedeking-Piret models were confirmed to provide a good description of gellan gum fermentation, which gave some support for the study of gellan gum fermentation kinetics. Additionally, this study is the first demonstration that gellan gum production is largely growth associated by analysis of kinetics in its batch fermentation process. Based on model prediction, higher gellan gum production (17.71 g liter−1) and higher conversion efficiency (57.12%) were obtained in fed-batch fermentation at the same total glucose concentration (30 g liter−1). PMID:16672479

  19. Modeling for gellan gum production by Sphingomonas paucimobilis ATCC 31461 in a simplified medium.

    PubMed

    Wang, Xia; Xu, Ping; Yuan, Yong; Liu, Changlong; Zhang, Dezhong; Yang, Zhengting; Yang, Chunyu; Ma, Cuiqing

    2006-05-01

    Gellan gum production was carried out by Sphingomonas paucimobilis ATCC 31461 in a simplified medium with a short incubation time, and a kinetic model for understanding, controlling, and optimizing the fermentation process was proposed. The results revealed that glucose was the best carbon source and that the optimal concentration was 30 g liter(-1). As for the fermenting parameters, considerably large amounts of gellan gum were yielded by an 8-h-old culture and a 4% inoculum at 200 rpm on a rotary shaker. Under the optimized conditions, the maximum level of gellan gum (14.75 g liter(-1)) and the highest conversion efficiency (49.17%) were obtained in a 30-liter fermentor in batch fermentation. Logistic and Luedeking-Piret models were confirmed to provide a good description of gellan gum fermentation, which gave some support for the study of gellan gum fermentation kinetics. Additionally, this study is the first demonstration that gellan gum production is largely growth associated by analysis of kinetics in its batch fermentation process. Based on model prediction, higher gellan gum production (17.71 g liter(-1)) and higher conversion efficiency (57.12%) were obtained in fed-batch fermentation at the same total glucose concentration (30 g liter(-1)). PMID:16672479

  20. Sulphate production by Paracoccus pantotrophus ATCC 35512 from different sulphur substrates: sodium thiosulphate, sulphite and sulphide.

    PubMed

    Meyer, Daniel Derrossi; Andrino, Felipe Gabriel; Possedente de Lira, Simone; Fornaro, Adalgiza; Corção, Gertrudes; Brandelli, Adriano

    2016-03-01

    One of the problems in waste water treatment plants (WWTPs) is the increase in emissions of hydrogen sulphide (H2S), which can cause damage to the health of human populations and ecosystems. To control emissions of this gas, sulphur-oxidizing bacteria can be used to convert H2S to sulphate. In this work, sulphate detection was performed by spectrophotometry, ion chromatography and atomic absorption spectrometry, using Paracoccus pantotrophus ATCC 35512 as a reference strain growing in an inorganic broth supplemented with sodium thiosulphate (Na2S2O3·5H2O), sodium sulphide (Na2S) or sodium sulphite (Na2SO3), separately. The strain was metabolically competent in sulphate production. However, it was only possible to observe significant differences in sulphate production compared to abiotic control when the inorganic medium was supplemented with sodium thiosulphate. The three methods for sulphate detection showed similar patterns, although the chromatographic method was the most sensitive for this study. This strain can be used as a reference for sulphate production in studies with sulphur-oxidizing bacteria originating from environmental samples of WWTPs. PMID:26269005

  1. Ca2+/calmodulin dependent protein kinase from Mycobacterium smegmatis ATCC 607.

    PubMed

    Sharma, S; Giri, S; Khuller, G K

    1998-06-01

    A soluble Ca2+/calmodulin dependent protein kinase has been partially purified (approximately 400 fold) from Mycobacterium smegmatis ATCC 607 using several purification steps like ammonium sulphate precipitation (30-60%), Sepharose CL-6B gel filtration, DEAE-cellulose and finally calmodulin-agarose affinity chromatography. On SDS-PAGE, this enzyme preparation showed a major protein band of molecular mass 35 kD and its activity was dependent on calcium, calmodulin and ATP when measured under saturating histone IIs (exogenous substrate) concentration. Phosphorylation of histone IIs was inhibited by W-7 (calmodulin inhibitor) and KN-62 (CaM-kinase inhibitor) with IC50 of 1.5 and 0.25 microm respectively, but was not affected by inhibitors of PKA (Sigma P5015) and PKC (H-7). All these results confirm that purified enzyme is Ca2+/calmodulin dependent protein kinase of M. smegmatis. The protein kinase of M. smegmatis demonstrated a narrow substrate specificity for both exogenous as well as endogenous substrates. These results suggest that purified CaM-kinase must be involved in regulating specific function(s) in this organism. PMID:9655195

  2. Production and structural analysis of the polysaccharide secreted by Trametes (Coriolus) versicolor ATCC 200801.

    PubMed

    Rau, Udo; Kuenz, Anja; Wray, Victor; Nimtz, Manfred; Wrenger, Julika; Cicek, Hasan

    2009-01-01

    Trametes versicolor ATCC 200801 secretes 4.1 g L(-1) of exopolysaccharide (EPS) when synthetic minimal medium and low-shear bioreactor cultivation technique are used. Structural and compositional analyses by thin layer chromatography, gas chromatography-mass spectrometry, electrospray ionization tandem mass spectrometry, and nuclear magnetic resonance spectroscopy yielded predominantly glucose and small amounts of galactose, mannose, arabinose, and xylose. The main EPS is composed of beta-1,3/beta-1,6-linked D-glucose molecules which is identical with Schizophyllan but does not possess a triple helical arrangement as secondary structure. Two molar mass fractions were detected by size exclusion chromatography yielding weight-average molecular weights of 4,100 and 2.6 kDa. Protein content varies between 2-3.6% (w/w). The exopolysaccharide is different in the nature of the glycosidic linkage, composition of monosaccharides, protein content, and weight-average molecular weight compared to the well-known polysaccharopeptide (PSP) and polysaccharopeptide Krestin (PSK). PMID:18800181

  3. Optimization of culture medium and conditions for penicillin acylase production by Streptomyces lavendulae ATCC 13664.

    PubMed

    Torres-Bacete, Jesús; Arroyo, Miguel; Torres-Guzmán, Raquel; De La Mata, Isabel; Acebal, Carmen; Castillón, M Pilar

    2005-08-01

    The culture medium for Streptomyces lavendulae ATCC 13664 was optimized on a shake-flask scale by using a statistical factorial design for enhanced production of penicillin acylase. This extracellular enzyme recently has been reported to be a penicillin K acylase, presenting also high hydrolytic activity against penicillin V and other natural aliphatic penicillins such as penicillin K, penicillin F, and penicillin dihydroF. The factorial design indicated that the main factors that positively affect penicillin acylase production by S. lavendulae were the concentration of yeast extract and the presence of oligoelements in the fermentation medium, whereas the presence of olive oil in the medium had no effect on enzyme production. An initial concentration of 2.5% (w/v) yeast extract and 3 microg/mL of CuSO4 x 5H2O was found to be best for acylase production. In such optimized culture medium, fermentation of the microorganism yielded 289 IU/L of enzyme in 72 h when employing a volume medium/volume flask ratio of 0.4 and a 300-rpm shaking speed. The presence of copper, alone and in combination with other metals, stimulated biomass as well as penicillin acylase production. The time course of penicillin acylase production was also studied in the optimized medium and conditions. Enzyme production showed catabolite repression by different carbon sources such as glucose, lactose, citrate, glycerol, and glycine. PMID:16118466

  4. Multi-functional glycoside hydrolase: Blon_0625 from Bifidobacterium longum subsp. infantis ATCC 15697.

    PubMed

    Matsumoto, Takuya; Shimada, Shota; Hata, Yuto; Tanaka, Tsutomu; Kondo, Akihiko

    2015-01-01

    We here describe a unique β-D-glucosidase (BGL; Blon_0625) derived from Bifidobacterium longum subsp. infantis ATCC 15697. The Blon_0625 gene was expressed by recombinant Escherichia coli. Purified recombinant Blon_0625 retains hydrolyzing activity against both p-nitrophenyl-β-D-glucopyranoside (pNPG; 17.3±0.24Umg(-1)) and p-nitrophenyl-β-D-xylopyranoside (pNPX; 16.7±0.32Umg(-1)) at pH 6.0, 30°C. To best of our knowledge, no previously described BGL retains the same level of both pNPGase and pNPXase activity. Furthermore, Blon_0625 also retains the activity against 4-nitrophenyl-α-l-arabinofranoside (pNPAf; 5.6±0.09Umg(-1)). In addition, the results of the degradation of phosphoric acid swollen cellulose (PASC) or xylan using endoglucanase from Thermobifida fusca YX (Tfu_0901) or xylanase from Kitasatospora setae KM-6054 (KSE_59480) show that Blon_0625 acts as a BGL and as a β-D-xylosidase (XYL) for hydrolyzing oligosaccharides. These results clearly indicate that Blon_0625 is a multi-functional glycoside hydrolase which retains the activity of BGL, XYL, and also α-l-arabinofuranosidase. Therefore, the utilization of multi-functional Blon_0625 may contribute to facilitating the efficient degradation of lignocellulosic materials and help enhance bioconversion processes. PMID:25435500

  5. Identification and characterization of the afsR homologue regulatory gene from Streptomyces peucetius ATCC 27952.

    PubMed

    Parajuli, Niranjan; Viet, Hung Trinh; Ishida, Kenji; Tong, Hang Thi; Lee, Hei Chan; Liou, Kwangkyoung; Sohng, Jae Kyung

    2005-01-01

    We have isolated an afsR homologue, called afsR-p, through genome analysis of Streptomyces peucetius ATCC 27952. AfsR-p shares 60% sequence identity with AfsR from Streptomyces coelicolor A3 (2). afsR-p was expressed under the control of the ermE* promoter in its hosts S. peucetius, Streptomyces lividans TK 24, Streptomyces clavuligerus and Streptomyces griseus. We observed overproduction of doxorubicin (4-fold) in S. peucetius, gamma-actinorhodin (2.6-fold) in S. lividans, clavulanic acid (1.5-fold) in S. clavuligerus and streptomycin (slight) in S. griseus. Overproduction was due to expression of the gene in these strains as compared to the wild-type strains harboring the vector only. Comparative study of the expression of afsR-p revealed that regulatory networking in Streptomyces is not uniform. We speculate that phosphorylated AfsR-p becomes bound to the promoter region of afsS. The latter activates other regulatory genes, including pathway regulatory genes, and induces the production of secondary metabolites including antibiotics. We identified specific conserved amino acids and exploited them for the isolation of the partial sequence of the afsR homologue from S. clavuligerus and Streptomyces achromogens (rubradirin producer). Such findings provide additional evidence for the presence of a serine/threonine and tyrosine kinase-dependent global regulatory network in Streptomyces. PMID:15921897

  6. Antimicrobial potential of immobilized Lactococcus lactis subsp. lactis ATCC 11454 against selected bacteria.

    PubMed

    Millette, M; Smoragiewicz, W; Lacroix, M

    2004-06-01

    Immobilization of living cells of lactic acid bacteria could be an alternative or complementary method of immobilizing organic acids and bacteriocins and inhibit undesirable bacteria in foods. This study evaluated the inhibition potential of immobilized Lactococcus lactis subsp. lactis ATCC 11454 on selected bacteria by a modified method of the agar spot test. L. lactis was immobilized in calcium alginate (1 to 2%)-whey protein concentrate (0 and 1%) beads. The antimicrobial potential of immobilized L. lactis was evaluated in microbiological media against pathogenic bacteria (Escherichia coli, Salmonella, and Staphylococcus aureus) or Pseudomonas putida, a natural meat contaminant, and against seven gram-positive bacteria used as indicator strains. Results obtained in this study indicated that immobilized L. lactis inhibited the growth of S. aureus, Enterococcus faecalis, Enterococcus faecium, Lactobacillus curvatus, Lactobacillus sakei, Kocuria varians, and Pediococcus acidilactici. Only 4 h of incubation at 35 degrees C resulted in a clear inhibition zone around the beads that increased with time. With the addition of 10 mM of a chelating agent (EDTA) to the media, results showed growth inhibition of E. coli; however, P. putida and Salmonella Typhi were unaffected by this treatment. These results indicate that immobilized lactic acid bacteria strains can be successfully used to produce nisin and inhibit bacterial growth in semisolid synthetic media. PMID:15222547

  7. Compositional and toxicological evaluation of the diazotrophic cyanobacterium, Cyanothece sp. strain ATCC 51142

    NASA Technical Reports Server (NTRS)

    Schneegurt, M. A.; Arieli, B.; McKeehen, J. D.; Stephens, S. D.; Nielsen, S. S.; Saha, P. R.; Trumbo, P. R.; Sherman, L. A.; Mitchell, C. A. (Principal Investigator)

    1995-01-01

    Compositional analyses of Cyanothece sp. strain ATCC 51142 showed high protein (50-60%) and low fat (0.4-1%) content, and the ability to synthesize vitamin B12. The amino acid profile indicated that Cyanothece sp. was a balanced protein source. Fatty acids of the 18:3n-3 type were also present. Mineral analyses indicated that the cellular biomass may be a good source of Fe, Zn and Na. Caloric content was 4.5 to 5.1 kcal g dry weight-1 and the carbon content was approximately 40% on a dry weight basis. Nitrogen content was 8 to 9% on a dry weight basis and total nucleic acids were 1.3% on a dry weight basis. Short-term feeding studies in rats followed by histopathology found no toxicity or dietary incompatibility problems. The level of uric acid and allantoin in urine and tissues was low, suggesting no excess of nucleic acids, as sometimes reported in the past for a cyanobacteria-containing diet. The current work discusses the potential implications of these results for human nutrition applications.

  8. Transcriptional and Mutational Analysis of the Uptake Hydrogenase of the Filamentous Cyanobacterium Anabaena variabilis ATCC 29413

    PubMed Central

    Happe, Thomas; Schütz, Kathrin; Böhme, Herbert

    2000-01-01

    A 10-kb DNA region of the cyanobacterium Anabaena variabilis ATCC 29413 containing the structural genes of the uptake hydrogenase (hupSL) was cloned and sequenced. In contrast to the hupL gene of Anabaena sp. strain PCC 7120, which is interrupted by a 10.5-kb DNA fragment in vegetative cells, there is no programmed rearrangement within the hupL gene during the heterocyst differentiation of A. variabilis. The hupSL genes were transcribed as a 2.7-kb operon and were induced only under nitrogen-fixing conditions, as shown by Northern blot experiments and reverse transcriptase PCR. Primer extension experiments with a fluorescence-labeled oligonucleotide primer confirmed these results and identified the 5′ start of the mRNA transcript 103 bp upstream of the ATG initiation codon. A consensus sequence in the promoter that is recognized by the fumarate nitrate reductase regulator (Fnr) could be detected. The hupSL operon in A. variabilis was interrupted by an interposon deletion (mutant strain AVM13). Under N2-fixing conditions, the mutant strain exhibited significantly increased rates in H2 accumulation and produced three times more hydrogen than the wild type. These results indicate that the uptake hydrogenase is catalytically active in the wild type and that the enzyme reoxidizes the H2 developed by the nitrogenase. The Nif phenotype of the mutant strain showed a slight decrease of acetylene reduction compared to that of the wild type. PMID:10692368

  9. Improved welan gum production by Alcaligenes sp. ATCC31555 from pretreated cane molasses.

    PubMed

    Ai, Hongxia; Liu, Min; Yu, Pingru; Zhang, Shaozhi; Suo, Yukai; Luo, Ping; Li, Shuang; Wang, Jufang

    2015-09-20

    Welan gum production by Alcaligenes sp. ATCC31555 from cane molasses was studied in batch fermentation to reduce production costs and enhance gum production. The pretreatment of cane molasses, agitation speed and the addition of supplements were investigated to optimize the process. Sulfuric acid hydrolysis was found to be the optimal pretreatment, resulting in a maximum gum concentration of 33.5 g/L, which is 50.0% higher than those obtained from the molasses' mother liquor. Agitation at 600 rpm at 30°C and addition of 10% n-dodecane following fermentation for 36 h increased the maximum gum production up to 41.0 ± 1.41 g/L, which is 49.1% higher than the greatest welan gum concentration in the literature so far. The welan gum product showed an acceptable molecular weight, similar rheological properties and better thermal stability to that obtained from glucose. These results indicate that cane molasses may be a suitable and inexpensive substrate for cost-effective industrial-scale welan gum production. PMID:26050885

  10. Pivotal role of anthranilate dioxygenase genes in the adaptation of Burkholderia multivorans ATCC 17616 in soil.

    PubMed

    Nishiyama, Eri; Ohtsubo, Yoshiyuki; Yamamoto, Yasuhiro; Nagata, Yuji; Tsuda, Masataka

    2012-05-01

    In our recent screen for soil-induced genes, the expression of andA operon (andAcAdAbAa) for anthranilate catabolism in Burkholderia multivorans ATCC 17616 was found to increase dramatically in a soil sample (Nishiyama et al., Environ Microbiol 12: 2539, 2010). The operon was preceded by andR encoding a putative transcriptional regulator for the andA operon. In this study, the andA promoter was induced by tryptophan and anthranilate in an andR-dependent manner. The andA promoter in a deletion mutant lacking tryptophan dioxygenase (one of enzymes for the catabolism of tryptophan to anthranilate) did not respond to tryptophan, indicating that not tryptophan but anthranilate is the effector of AndR. Although both anthranilate and tryptophan were under the detection levels in the soil sample, andA promoter showed higher activity in the soil sample than in a laboratory medium. Such induction required andR and was moderately dependent on the ferric uptake regulator (Fur). The proliferation ability of andAc mutant in the sterile soil was low compared with the co-incubated wild-type cells. These findings suggested that in the soil environment, anthranilate dioxygenase genes are induced by AndR and Fur, and play a pivotal role in the proliferation in the soil environment. PMID:22360670

  11. Purification and characterization of acidolysin, an acidic metalloprotease produced by Clostridium acetobutylicum ATCC 824.

    PubMed Central

    Croux, C; Paquet, V; Goma, G; Soucaille, P

    1990-01-01

    Acidolysin an extracellular protease produced by Clostridium acetobutylicum ATCC 824 was purified to homogeneity by anion-exchange chromatography with a recovery of 91%. The enzyme was a monomeric protein with a molecular weight of 44,000 as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and an acidic isoelectric point of 3.3. Acidolysin was very sensitive to metal-chelating agents and phosphoramidon and was unaffected by sulfhydryl reagents. It was shown to be a calcium- and zinc-containing protease. It exhibited optimal activity against Azocoll at pH 5 and 45 degrees C. It was stable at low pH and heat labile above 50 degrees C. It exhibited specificity toward peptide bonds formed by the amino group of hydrophobic amino acids (isoleucine, leucine, and phenylalanine) and its NH2-terminal amino acid sequence showed a high degree of similarity with that of Bacillus subtilis neutral metalloprotease A. Acidolysin is the first phosphoramidon-sensitive, acidic zinc metalloprotease reported. Images PMID:2082818

  12. Construction and evaluation of a Clostridium thermocellum ATCC 27405 whole-genome oligonucleotide microarray

    SciTech Connect

    Brown, Steven David; Raman, Babu; McKeown, Catherine K; Kale, Shubhangi P; He, Zhili; Mielenz, Jonathan R

    2007-04-01

    Clostridium thermocellum is an anaerobic, thermophilic bacterium that can directly convert cellulosic substrates into ethanol. Microarray technology is a powerful tool to gain insights into cellular processes by examining gene expression under various physiological states. Oligonucleotide microarray probes were designed for 96.7% of the 3163 C. thermocellum ATCC 27405 candidate protein-encoding genes and then a partial-genome microarray containing 70 C. thermocellum specific probes was constructed and evaluated. We detected a signal-to-noise ratio of three with as little as 1.0 ng of genomic DNA and only low signals from negative control probes (nonclostridial DNA), indicating the probes were sensitive and specific. In order to further test the specificity of the array we amplified and hybridized 10 C. thermocellum polymerase chain reaction products that represented different genes and found gene specific hybridization in each case. We also constructed a whole-genome microarray and prepared total cellular RNA from the same point in early-logarithmic growth phase from two technical replicates during cellobiose fermentation. The reliability of the microarray data was assessed by cohybridization of labeled complementary DNA from the cellobiose fermentation samples and the pattern of hybridization revealed a linear correlation. These results taken together suggest that our oligonucleotide probe set can be used for sensitive and specific C. thermocellum transcriptomic studies in the future.

  13. Sucrose fermentation by Fusobacterium mortiferum ATCC 25557: transport, catabolism, and products.

    PubMed Central

    Thompson, J; Nguyen, N Y; Robrish, S A

    1992-01-01

    Studies of sucrose utilization by Fusobacterium mortiferum ATCC 25557 have provided the first definitive evidence for phosphoenolpyruvate-dependent sugar:phosphotransferase activity in the family Bacteroidaceae. The phosphoenolpyruvate-dependent sucrose:phosphotransferase system and the two enzymes required for the dissimilation of sucrose 6-phosphate are induced specifically by growth of F. mortiferum on the disaccharide. Monomeric sucrose 6-phosphate hydrolase (M(r), 52,000) and a dimeric ATP-dependent fructokinase (subunit M(r), 32,000) have been purified to electrophoretic homogeneity. The physicochemical and catalytic properties of these enzymes have been examined, and the N-terminal amino acid sequences for both proteins are reported. The characteristics of sucrose 6-phosphate hydrolase and fructokinase from F. mortiferum are compared with the same enzymes from both gram-positive and gram-negative species. Butyric, acetic, and D-lactic acids are the end products of sucrose fermentation by F. mortiferum. A pathway is proposed for the translocation, phosphorylation, and metabolism of sucrose by this anaerobic pathogen. Images PMID:1533618

  14. Production of single cell oil from Lipomyces starkeyi ATCC 56304 using biorefinery by-products.

    PubMed

    Probst, Kyle V; Vadlani, Praveen V

    2015-12-01

    Single cell oil (SCO) is a valuable noncrop-based renewable oil source. Hemicellulose derived sugars can be utilized to produce SCO using the oleaginous yeast Lipomyces starkeyi ATCC 56304. Bran by-products were tested as hemicellulose-rich feedstocks for the production of SCO. Whole and destarched corn and wheat bran hydrolysates were produced using hydrothermal and dilute sulfuric acid (0%, 0.5%, 1.0%, v/v) pretreatment along with enzymatic hydrolysis. Whole bran hydrolysates produced from hydrothermal pretreatment generated the highest average oil yields of 126.7 and 124.3 mg oil/g sugar for both wheat and corn bran, respectively. 1.0% acid pretreatment was effective for the destarched bran generating a hemicellulose hydrolysis efficiency of 94% and 84% for wheat and corn bran, respectively, resulting in the highest oil yield of 70.7 mg oil/g sugar. The results indicate pretreated corn and wheat bran hydrolysates can serve as viable feedstocks for oleaginous yeast SCO bioconversion. PMID:26402869

  15. Catabolite repression in Lactobacillus casei ATCC 393 is mediated by CcpA.

    PubMed Central

    Monedero, V; Gosalbes, M J; Pérez-Martínez, G

    1997-01-01

    The chromosomal ccpA gene from Lactobacillus casei ATCC 393 has been cloned and sequenced. It encodes the CcpA protein, a central catabolite regulator belonging to the LacI-GalR family of bacterial repressors, and shows 54% identity with CcpA proteins from Bacillus subtilis and Bacillus megaterium. The L. casei ccpA gene was able to complement a B. subtilis ccpA mutant. An L. casei ccpA mutant showed increased doubling times and a relief of the catabolite repression of some enzymatic activities, such as N-acetylglucosaminidase and phospho-beta-galactosidase. Detailed analysis of CcpA activity was performed by using the promoter region of the L. casei chromosomal lacTEGF operon which is subject to catabolite repression and contains a catabolite responsive element (cre) consensus sequence. Deletion of this cre site or the presence of the ccpA mutation abolished the catabolite repression of a lacp::gusA fusion. These data support the role of CcpA as a common regulatory element mediating catabolite repression in low-GC-content gram-positive bacteria. PMID:9352913

  16. Immunobiological activities of a porin fraction isolated from Fusobacterium nucleatum ATCC 10953.

    PubMed Central

    Takada, H; Ogawa, T; Yoshimura, F; Otsuka, K; Kokeguchi, S; Kato, K; Umemoto, T; Kotani, S

    1988-01-01

    From Fusobacterium nucleatum ATCC 10953 cell envelope fraction whose inner membranes had been removed by treatment with sodium N-lauroyl sarcosinate, an outer membrane protein (37,000 Mr in a native state) was prepared by extraction with lithium dodecyl sulfate. The protein thus obtained showed distinct porin activity, namely, the ability to form hydrophilic diffusion pores by incorporation into the artificial liposome membrane. The porin fraction exhibited strong immunobiological activities in the in vitro assays: B-cell mitogenicity and polyclonal B-cell activation on murine splenocytes, stimulatory effects on guinea pig peritoneal macrophages, and enhancement of the migration of human blood monocytes. The porin fraction also exhibited immunoadjuvant activity to increase the antibody production against sheep erythrocytes in the spleen of mice that were immunized by sheep erythrocytes with porin. Although chemical analyses revealed that the test porin fraction contained a considerable amount of lipopolysaccharide (LPS) (around 12% of the fraction), the studies with LPS-nonresponding C3H/HeJ mice and on the inhibitory effects of polymyxin B strongly suggest that most of the above bioactivities are due to porin protein itself, not to coexistent LPS in the porin fraction. Images PMID:2831155

  17. Evaluation of Cyanothece sp. ATCC 51142 as a candidate for inclusion in a CELSS

    NASA Technical Reports Server (NTRS)

    Schneegurt, M. A.; Arieli, B.; Nielsen, S. S.; Trumbo, P. R.; Sherman, L. A.; Mitchell, C. A. (Principal Investigator)

    1996-01-01

    Controlled ecological life support systems (CELSS) have been proposed to make long-duration manned space flights more cost-effective. Higher plants will presumably provide food and a breathable atmosphere for the crew. It has been suggested that imbalances between the CO2/O2 gas exchange ratios of the heterotrophic and autotrophic components of the system will inevitably lead to an unstable system, and the loss of O2 from the atmosphere. Ratio imbalances may be corrected by including a second autotroph with an appropriate CO2/O2 gas exchange ratio. Cyanothece sp. ATCC 51142 is a large unicellular N2-fixing cyanobacterium, exhibiting high growth rates under diverse physiological conditions. A rat-feeding study showed the biomass to be edible. Furthermore, it may have a CO2/O2 gas exchange ratio that theoretically can compensate for ratio imbalances. It is suggested that Cyanothece spp. could fulfill several roles in a CELSS: supplementing atmosphere recycling, generating fixed N from the air, providing a balanced protein supplement, and protecting a CELSS in case of catastrophic crop failure.

  18. Evaluation of Cyanothece sp. ATCC 51142 as a candidate for inclusion in a CELSS.

    PubMed

    Schneegurt, M A; Arieli, B; Nielsen, S S; Trumbo, P R; Sherman, L A

    1996-01-01

    Controlled ecological life support systems (CELSS) have been proposed to make long-duration manned space flights more cost-effective. Higher plants will presumably provide food and a breathable atmosphere for the crew. It has been suggested that imbalances between the CO2/O2 gas exchange ratios of the heterotrophic and autotrophic components of the system will inevitably lead to an unstable system, and the loss of O2 from the atmosphere. Ratio imbalances may be corrected by including a second autotroph with an appropriate CO2/O2 gas exchange ratio. Cyanothece sp. ATCC 51142 is a large unicellular N2-fixing cyanobacterium, exhibiting high growth rates under diverse physiological conditions. A rat-feeding study showed the biomass to be edible. Furthermore, it may have a CO2/O2 gas exchange ratio that theoretically can compensate for ratio imbalances. It is suggested that Cyanothece spp. could fulfill several roles in a CELSS: supplementing atmosphere recycling, generating fixed N from the air, providing a balanced protein supplement, and protecting a CELSS in case of catastrophic crop failure. PMID:11538794

  19. Sophorolipids Production by Candida bombicola ATCC 22214 and its Potential Application in Microbial Enhanced Oil Recovery

    PubMed Central

    Elshafie, Abdulkadir E.; Joshi, Sanket J.; Al-Wahaibi, Yahya M.; Al-Bemani, Ali S.; Al-Bahry, Saif N.; Al-Maqbali, Dua’a; Banat, Ibrahim M.

    2015-01-01

    Biosurfactant production using Candida bombicola ATCC 22214, its characterization and potential applications in enhancing oil recovery were studied at laboratory scale. The seed media and the production media were standardized for optimal growth and biosurfactant production. The production media were tested with different carbon sources: glucose (2%w/v) and corn oil (10%v/v) added separately or concurrently. The samples were collected at 24 h interval up to 120 h and checked for growth (OD660), and biosurfactant production [surface tension (ST) and interfacial tension (IFT)]. The medium with both glucose and corn oil gave better biosurfactant production and reduced both ST and IFT to 28.56 + 0.42mN/m and 2.13 + 0.09mN/m, respectively within 72 h. The produced biosurfactant was quite stable at 13–15% salinity, pH range of 2–12, and at temperature up to 100°C. It also produced stable emulsions (%E24) with different hydrocarbons (pentane, hexane, heptane, tridecane, tetradecane, hexadecane, 1-methylnaphthalene, 2,2,4,4,6,8-heptamethylnonane, light and heavy crude oil). The produced biosurfactant was extracted using ethyl acetate and characterized as a mixture of sophorolipids (SPLs). The potential of SPLs in enhancing oil recovery was tested using core-flooding experiments under reservoir conditions, where additional 27.27% of residual oil (Sor) was recovered. This confirmed the potential of SPLs for applications in microbial enhanced oil recovery. PMID:26635782

  20. A model of cyclic transcriptomic behavior in the cyanobacterium Cyanothece sp. ATCC 51142.

    PubMed

    McDermott, Jason E; Oehmen, Christopher S; McCue, Lee Ann; Hill, Eric; Choi, Daniel M; Stöckel, Jana; Liberton, Michelle; Pakrasi, Himadri B; Sherman, Louis A

    2011-08-01

    Systems biology attempts to reconcile large amounts of disparate data with existing knowledge to provide models of functioning biological systems. The cyanobacterium Cyanothece sp. ATCC 51142 is an excellent candidate for such systems biology studies because: (i) it displays tight functional regulation between photosynthesis and nitrogen fixation; (ii) it has robust cyclic patterns at the genetic, protein and metabolomic levels; and (iii) it has potential applications for bioenergy production and carbon sequestration. We have represented the transcriptomic data from Cyanothece 51142 under diurnal light/dark cycles as a high-level functional abstraction and describe development of a predictive in silico model of diurnal and circadian behavior in terms of regulatory and metabolic processes in this organism. We show that incorporating network topology into the model improves performance in terms of our ability to explain the behavior of the system under new conditions. The model presented robustly describes transcriptomic behavior of Cyanothece 51142 under different cyclic and non-cyclic growth conditions, and represents a significant advance in the understanding of gene regulation in this important organism. PMID:21698331

  1. Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064

    PubMed Central

    da Silva Vasconcelos, Eliton; de Lima, Vanderlei Aparecido; Goto, Leandro Seiji; Cruz-Hernández, Isara Lourdes; Hokka, Carlos Osamu

    2013-01-01

    Clavulanic acid (CA) is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064). The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant. PMID:24688492

  2. Physical and genetic map of the Clostridium acetobutylicum ATCC 824 chromosome.

    PubMed Central

    Cornillot, E; Croux, C; Soucaille, P

    1997-01-01

    A physical and genetic map of the Clostridium acetobutylicum ATCC 824 chromosome was constructed. The macrorestriction map for CeuI, EagI, and SstII was created by ordering the 38 restriction sites by one- and two-dimensional pulsed-field gel electrophoresis (PFGE) and by using an original strategy based on the CeuI enzyme and indirect end labelling by hybridization on both sides of the CeuI sites with rrs (16S RNA) and 3' rrl (23S RNA) probes. The circular chromosome was estimated to be 4.15 Mb in size, and the average resolution of the physical map is 110 kb. The chromosome contains 11 rrn loci, which are localized on 44% of the chromosome in a divergent transcriptional orientation regarding the presumed location of the replication origin. In addition to these 11 rrn operons, a total of 40 identified genes were mapped by hybridization experiments with genes from C. acetobutylicum and from various other clostridia as probes. The genetic map of C. acetobutylicum was compared to that of the three other endospore-forming bacteria characterized so far: Bacillus subtilis, Clostridium beijerinckii, and Clostridium perfringens. Parodoxically, the chromosomal backbone of C. acetobutylicum showed more similarity to that of B. subtilis than to those of the clostridia. PMID:9393708

  3. In vitro and in vivo activities of ticarcillin-loaded nanoliposomes with different surface charges against Pseudomonas aeruginosa (ATCC 29248)

    PubMed Central

    2012-01-01

    Background Pseudomonas aeruginosa exhibits multiple antibiotic resistance mechanisms. Different studies have shown that entrapment of antibiotics into liposomes could increase their anti-Pseudomonas activity. The objectives of this study were to prepare ticarcillin loaded-nanoliposomes with variable surface charges and evaluate their in vitro and in vivo efficacies against Pseudomonas aeruginosa (ATCC 29248). Methods Ticarcillin-loaded nanoliposomes with positive, negative and neutral surface charges were prepared by extrusion method. Ticarcillin encapsulation efficacies for different formulations were measured by HPLC method. Minimum inhibitory concentration (MIC) of ticarcillin nanoliposomal forms against strain ATCC 29248 were determined by broth dilution method. The killing rate of Pseudomonas aeruginosa was exposed to various concentrations of ticarcillin in free and nanoliposomal forms were analyzed. Ultimately, in vivo therapeutic efficacy of nanoliposomes in burned mice skin infected with strain ATCC 29248 was investigated. Results The encapsulation efficacies for ticarcillin-loaded cationic nanoliposomes were significantly higher (76% ± 0.17) than those of neutral (55% ± 0.14) and anionic (43% ± 0.14) nanoliposomes. The MIC of free, cationic, neutral and anionic nanoliposomal forms of ticarcillin against ATCC 29248 were to 24, 3, 6 and 48 mg/L, respectively. The killing rates of ticarcillin-loaded cationic nanoliposomes were higher than those of free and other drug formulations. Treatment by ticarcillin-loaded nanoliposomes with positive, neutral and negative surface charges resulted in almost 100, 60 and 20% survival rates, respectively. Conclusion Our data suggested that cationic ticarcillin-loaded nanoliposomes because of high effectiveness would be a good choice to treatment of Pseudomonas aeruginosa infections. PMID:23351156

  4. Classification of Nonomuraea sp. ATCC 39727, an actinomycete that produces the glycopeptide antibiotic A40926, as Nonomuraea gerenzanensis sp. nov.

    PubMed

    Dalmastri, Claudia; Gastaldo, Luciano; Marcone, Giorgia Letizia; Binda, Elisa; Congiu, Terenzio; Marinelli, Flavia

    2016-02-01

    Strain ATCC 39727, which produces the antibiotic A40926 (the natural precursor of the antibiotic dalbavancin), was isolated from a soil sample collected in India, and it was originally classified as a member of the genus Actinomadura on the base of morphology and cell-wall composition. A phylogenetic analysis based on 16S rRNA gene sequences indicates that the strain forms a distinct clade within the genus Nonomuraea, and it is most closely related to Nonomuraea angiospora DSM 43173T (98.72 % similarity) and Nonomuraea jabiensis A4036T (98.69 %). The strain forms an extensively branched substrate mycelium and aerial hyphae that form spiral chains of spores with ridged surfaces. The cell wall contains meso-diaminopimelic acid and the whole-cell sugars are glucose, ribose, galactose, mannose and madurose (madurose as the diagnostic sugar). The N-acyl type of muramic acid is acetyl. The predominant menaquinone is MK-9(H4), with minor amounts of MK-9(H2), MK-9(H6) and MK-9(H0). The polar-lipid profile includes diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxyphosphatidylmethylethanolamine, phosphatidylinositol and a series of uncharacterized phospholipids, glycolipids and phosphoglycolipids. The major cellular fatty acids are iso-C16 : 0 and 10-methyl C17 : 0. The genomic DNA G+C content is 71.2 mol%. Significant differences in the morphological, chemotaxonomic and biochemical data, together with DNA-DNA relatedness between strain ATCC 39727 and closely related type strains, clearly demonstrated that strain ATCC 39727 represents a novel species of the genus Nonomuraea, for which the name Nonomuraea gerenzanensis sp. nov. is proposed. The type strain is ATCC 39727T ( = DSM 100948T). PMID:26944798

  5. Complete Genome Sequence of Mycoplasma hominis Strain Sprott (ATCC 33131), Isolated from a Patient with Nongonococcal Urethritis

    PubMed Central

    Foecking, Mark F.

    2015-01-01

    Presented here is the complete and annotated genome sequence of Mycoplasma hominis Sprott (ATCC 33131). The chromosome comprises 695,214 bp, which is approximately 30 kb larger than the syntenic genome of M. hominis PG21T. Tetracycline resistance of strain Sprott is most probably conferred by the tetM determinant, harbored on a mosaic transposon-like structure. PMID:26159538

  6. Co-culturing a novel Bacillus strain with Clostridium tyrobutyricum ATCC 25755 to produce butyric acid from sucrose

    PubMed Central

    2013-01-01

    Background Currently, the most promising microorganism used for the bio-production of butyric acid is Clostridium tyrobutyricum ATCC 25755T; however, it is unable to use sucrose as a sole carbon source. Consequently, a newly isolated strain, Bacillus sp. SGP1, that was found to produce a levansucrase enzyme, which hydrolyzes sucrose into fructose and glucose, was used in a co-culture with this strain, permitting C. tyrobutyricum ATCC 25755T to ferment sucrose to butyric acid. Results B. sp. SGP1 alone did not show any butyric acid production and the main metabolite produced was lactic acid. This allowed C. tyrobutyricum ATCC 25755T to utilize the monosaccharides resulting from the activity of levansucrase together with the lactic acid produced by B. sp. SGP1 to generate butyric acid, which was the main fermentative product within the co-culture. Furthermore, the final acetic acid concentration in the co-culture was significantly lower when compared with pure C. tyrobutyricum ATCC 25755T cultures grown on glucose. In fed-batch fermentations, the optimum conditions for the production of butyric acid were around pH 5.50 and a temperature of 37°C. Under these conditions, the final butyrate concentration was 34.2±1.8 g/L with yields of 0.35±0.03 g butyrate/g sucrose and maximum productivity of 0.3±0.04 g/L/h. Conclusions Using this co-culture, sucrose can be utilized as a carbon source for butyric acid production at a relatively high yield. In addition, this co-culture offers also the benefit of a greater selectivity, with butyric acid constituting 92.8% of the acids when the fermentation was terminated. PMID:23452443

  7. Pelczaria aurantia ATCC 49321T (=DSM 12801T) is a strain of Kocuria rosea (Flügge 1886) Stackebrandt et al. 1995.

    PubMed

    Schumann, P; Tindall, B J; Mendrock, U; Kramer, I; Stackebrandt, E

    2000-07-01

    Phylogenetic and chemotaxonomic analyses of Pelczaria aurantia ATCC 49321T (= DSM 12801T) indicate that this species is very closely related to Kocuria rosea. The DNA-DNA reassociation value of 87.1% determined for the type strains of the two species supports this finding. The results of phylogenetic analysis of the 16S rDNA of a subculture of the original strain of Pelczaria aurantia, deposited at the National Institutes of Health, Bethesda, MD, USA, as 'Neisseria aurantia', are identical to those for strain ATCC 49321T and indicate that Pelczaria aurantia ATCC 49321T is an authentic subculture of the original culture described by Poston (1993). On the basis of these findings it is concluded that P. aurantia ATCC 49321T and K. rosea DSM 20447T are members of the same taxon. The taxonomic consequences of this union are discussed. PMID:10939645

  8. Expression of arsenic resistance genes in the obligate anaerobe Bacteroides vulgatus ATCC 8482, a gut microbiome bacterium.

    PubMed

    Li, Jiaojiao; Mandal, Goutam; Rosen, Barry P

    2016-06-01

    The response of the obligate anaerobe Bacteroides vulgatus ATCC 8482, a common human gut microbiota, to arsenic was determined. B. vulgatus ATCC 8482 is highly resistant to pentavalent As(V) and methylarsenate (MAs(V)). It is somewhat more sensitive to trivalent inorganic As(III) but 100-fold more sensitive to methylarsenite (MAs(III)) than to As(III). B. vulgatus ATCC 8482 has eight continuous genes in its genome that we demonstrate form an arsenical-inducible transcriptional unit. The first gene of this ars operon, arsR, encodes a putative ArsR As(III)-responsive transcriptional repressor. The next three genes encode proteins of unknown function. The remaining genes, arsDABC, have well-characterized roles in detoxification of inorganic arsenic, but there are no known genes for MAs(III) resistance. Expression of each gene after exposure to trivalent and pentavalent inorganic and methylarsenicals was analyzed. MAs(III) was the most effective inducer. The arsD gene was the most highly expressed of the ars operon genes. These results demonstrate that this anaerobic microbiome bacterium has arsenic-responsive genes that confer resistance to inorganic arsenic and may be responsible for the organism's ability to maintain its prevalence in the gut following dietary exposure to inorganic arsenic. PMID:27040269

  9. Transcriptome analysis of Cronobacter sakazakii ATCC BAA-894 after interaction with human intestinal epithelial cell line HCT-8.

    PubMed

    Jing, Chun-e; Du, Xin-jun; Li, Ping; Wang, Shuo

    2016-01-01

    Cronobacter spp. are opportunistic pathogens that are responsible for infections including severe meningitis, septicemia, and necrotizing enterocolitis in neonates and infants. To date, questions still remain regarding the mechanisms of pathogenicity and virulence determinants for each bacterial strain. In this study, we established an in vitro model for Cronobacter sakazakii ATCC BAA-894 infection of HCT-8 human colorectal epithelial cells. The transcriptome profile of C. sakazakii ATCC BAA-894 after interaction with HCT-8 cells was determined using high-throughput whole-transcriptome sequencing (RNA sequencing (RNA-seq)). Gene expression profiles indicated that 139 genes were upregulated and 72 genes were downregulated in the adherent C. sakazakii ATCC BAA-894 strain on HCT-8 cells compared to the cultured bacteria in the cell-free medium. Expressions of some flagella genes and virulence factors involved in adherence were upregulated. High osmolarity and osmotic stress-associated genes were highly upregulated, as well as genes responsible for the synthesis of lipopolysaccharides and outer membrane proteins, iron acquisition systems, and glycerol and glycerophospholipid metabolism. In sum, our study provides further insight into the mechanisms underlying C. sakazakii pathogenesis in the human gastrointestinal tract. PMID:26481623

  10. Selection of the Strain Lactobacillus acidophilus ATCC 43121 and Its Application to Brewers' Spent Grain Conversion into Lactic Acid

    PubMed Central

    Liguori, Rossana; Soccol, Carlos Ricardo; Vandenberghe, Luciana Porto de Souza; Woiciechowski, Adenise Lorenci; Ionata, Elena; Marcolongo, Loredana; Faraco, Vincenza

    2015-01-01

    Six Lactobacillus strains were analyzed to select a bacterium for conversion of brewers' spent grain (BSG) into lactic acid. Among the investigated strains, L. acidophilus ATCC 43121 showed the highest yield of lactic acid production (16.1 g/L after 48 hours) when grown in a synthetic medium. It was then analyzed for its ability to grow on the hydrolysates obtained from BSG after acid-alkaline (AAT) or aqueous ammonia soaking (AAS) pretreatment. The lactic acid production by L. acidophilus ATCC 43121 through fermentation of the hydrolysate from AAS treated BSG was 96% higher than that from the AAT treated one, although similar yields of lactic acid per consumed glucose were achieved due to a higher (46%) glucose consumption by L. acidophilus ATCC 43121 in the AAS BSG hydrolysate. It is worth noting that adding yeast extract to the BSG hydrolysates increased both the yield of lactic acid per substrate consumed and the volumetric productivity. The best results were obtained by fermentation of AAS BSG hydrolysate supplemented by yeast extract, in which the strain produced 22.16 g/L of lactic acid (yield of 0.61 g/g), 27% higher than the value (17.49 g/L) obtained in the absence of a nitrogen source. PMID:26640784

  11. Genome mining of astaxanthin biosynthetic genes from Sphingomonas sp. ATCC 55669 for heterologous overproduction in Escherichia coli.

    PubMed

    Ma, Tian; Zhou, Yuanjie; Li, Xiaowei; Zhu, Fayin; Cheng, Yongbo; Liu, Yi; Deng, Zixin; Liu, Tiangang

    2016-02-01

    As a highly valued keto-carotenoid, astaxanthin is widely used in nutritional supplements and pharmaceuticals. Therefore, the demand for biosynthetic astaxanthin and improved efficiency of astaxanthin biosynthesis has driven the investigation of metabolic engineering of native astaxanthin producers and heterologous hosts. However, microbial resources for astaxanthin are limited. In this study, we found that the α-Proteobacterium Sphingomonas sp. ATCC 55669 could produce astaxanthin naturally. We used whole-genome sequencing to identify the astaxanthin biosynthetic pathway using a combined PacBio-Illumina approach. The putative astaxanthin biosynthetic pathway in Sphingomonas sp. ATCC 55669 was predicted. For further confirmation, a high-efficiency targeted engineering carotenoid synthesis platform was constructed in E. coli for identifying the functional roles of candidate genes. All genes involved in astaxanthin biosynthesis showed discrete distributions on the chromosome. Moreover, the overexpression of exogenous E. coli idi in Sphingomonas sp. ATCC 55669 increased astaxanthin production by 5.4-fold. This study described a new astaxanthin producer and provided more biosynthesis components for bioengineering of astaxanthin in the future. PMID:26580858

  12. Lactobacillus acidophilus ATCC 4356 inhibits biofilm formation by C. albicans and attenuates the experimental candidiasis in Galleria mellonella

    PubMed Central

    Vilela, Simone FG; Barbosa, Júnia O; Rossoni, Rodnei D; Santos, Jéssica D; Prata, Marcia CA; Anbinder, Ana Lia; Jorge, Antonio OC; Junqueira, Juliana C

    2015-01-01

    Probiotic strains of Lactobacillus have been studied for their inhibitory effects on Candida albicans. However, few studies have investigated the effect of these strains on biofilm formation, filamentation and C. albicans infection. The objective of this study was to evaluate the influence of Lactobacillus acidophilus ATCC 4356 on C. albicans ATCC 18804 using in vitro and in vivo models. In vitro analysis evaluated the effects of L. acidophilus on the biofilm formation and on the capacity of C. albicans filamentation. For in vivo study, Galleria mellonella was used as an infection model to evaluate the effects of L. acidophilus on candidiasis by survival analysis, quantification of C. albicans CFU/mL, and histological analysis. The direct effects of L. acidophilus cells on C. albicans, as well as the indirect effects using only a Lactobacillus culture filtrate, were evaluated in both tests. The in vitro results showed that both L. acidophilus cells and filtrate were able to inhibit C. albicans biofilm formation and filamentation. In the in vivo study, injection of L. acidophilus into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore, the number of C. albicans CFU/mL recovered from the larval hemolymph was lower in the group inoculated with L. acidophilus compared to the control group. In conclusion, L. acidophilus ATCC 4356 inhibited in vitro biofilm formation by C. albicans and protected G. mellonella against experimental candidiasis in vivo. PMID:25654408

  13. Genome Sequences of Ralstonia insidiosa Type Strain ATCC 49129 and Strain FC1138, a Strong Biofilm Producer Isolated from a Fresh-Cut Produce-Processing Plant

    PubMed Central

    Xu, Yunfeng; Nagy, Attila; Yan, Xianghe; Haley, Bradd J.; Kim, Seon Woo; Liu, Nancy T.

    2016-01-01

    Ralstonia insidiosa is an opportunistic pathogen and a strong biofilm producer. Here, we present the complete genome sequences of R. insidiosa FC1138 and ATCC 49129. Both strains have two circular chromosomes of approximately 3.9 and 1.9 Mb and a 50-kb plasmid. ATCC 49129 also possesses a megaplasmid of approximately 318 kb. PMID:27540070

  14. Acidithrix ferrooxidans gen. nov., sp. nov.; a filamentous and obligately heterotrophic, acidophilic member of the Actinobacteria that catalyzes dissimilatory oxido-reduction of iron.

    PubMed

    Jones, Rose M; Johnson, D Barrie

    2015-01-01

    A novel acidophilic member of the phylum Actinobacteria was isolated from an acidic stream draining an abandoned copper mine in north Wales. The isolate (PY-F3) was demonstrated to be a heterotroph that catalyzed the oxidation of ferrous iron (but not of sulfur or hydrogen) under aerobic conditions, and the reduction of ferric iron under micro-aerobic and anaerobic conditions. PY-F3 formed long entangled filaments of cells (>50 μm long) during active growth phases, though these degenerated into smaller fragments and single cells in late stationary phase. Although isolate PY-F3 was not observed to grow below pH 2.0 and 10 °C, harvested biomass was found to oxidize ferrous iron at relatively fast rates at pH 1.5 and 5 °C. Phylogenetic analysis, based on comparisons of 16S rRNA gene sequences, showed that isolate PY-F3 has 91-93% gene similarity to those of the four classified genera and species of acidophilic Actinobacteria, and therefore is a representative of a novel genus. The binomial Acidithrix ferrooxidans is proposed for this new species, with PY-F3 as the designated type strain (=DSM 28176(T), =JCM 19728(T)). PMID:25638020

  15. Antibacterial activity of antagonistic bacterium Bacillus subtilis DJM-51 against phytopathogenic Clavibacter michiganense subsp. michiganense ATCC 7429 in vitro.

    PubMed

    Jung, W J; Mabood, F; Souleimanov, A; Whyte, L G; Niederberger, T D; Smith, D L

    2014-12-01

    To investigate antibacterial activity against the tomato pathogen Clavibacter michiganense subsp. michiganense ATCC 7429 (Cmm ATCC 7429), Bacillus subtilis DJM-51 was isolated from rhizosphere soil. For isolation of bacteria, samples were taken from rhizosphere soil. The isolate, DJA-51, had strong antagonistic ability against Tomato pathogen Cmm ATCC 7429 on nutrient-broth yeast extract agar (NBYA) as indicated by inhibition zones around colonies. On the basis of the nucleotide sequence of a conserved segment of the 16S rRNA gene, the bacterium has been identified as B. subtilis DJM-51. The growth of Cmm ATCC 7429 on NBYA plates was inhibited by culture broth of B. subtilis DJM-51 including cells, by the supernatant of culture broth of B. subtilis DJM-51, and by the liquid material resulting from butanol extract of bacterial cultures. The OD value in co-culture mixture was lower than the control throughout the entire incubation period. Antibiotics obtained from B. subtilis DJM-51 inhibited the growth of Tomato pathogen Cmm ATCC 7429. These results provide potentially information about the protection of tomato from pathogen Cmm ATCC 7429 under greenhouse conditions in Quebec. PMID:25457795

  16. Differential proteomic analysis of Clostridium perfringens ATCC13124; identification of dominant, surface and structure associated proteins

    PubMed Central

    2009-01-01

    Background Clostridium perfringens is a medically important clostridial pathogen causing diseases in man and animals. To invade, multiply and colonize tissues of the host, a pathogen must be able to evade host immune system, and obtain nutrients essential for growth. The factors involved in these complex processes are largely unknown and of crucial importance to understanding microbial pathogenesis. Many of the virulence determinants and putative vaccine candidates for bacterial pathogens are known to be surface localized. Results Using 2-DE mass spectrometry strategy, we identified major surface (22) and cell envelope (10) proteins from Clostridium perfringens ATCC13124 and those differentially expressed (11) in cells grown on cooked meat medium (CMM) in comparison with cells grown in reference state (tryptose-yeast extract-glucose medium). Riboflavin biosynthesis protein, ornithine carbamoyltransferase, cystathionine beta-lyase, and threonine dehydratase were the predominant proteins that exhibited 2.19 to 8.5 fold increase in the expression level in cells growing on CMM. Conclusion Ornithine carbamoyltransferase and cystathionine beta-lyase were over-expressed in cells grown on cooked meat medium and also identified in the surface protein fraction and the former was immunogenic; making them potential vaccine candidates. Based upon bioinformatic analysis; choloylglycine hydrolase family protein, cell wall-associated serine proteinase, and rhomboid family protein were predicted as surface protein markers for specific detection of C. perfringens from the environment and food. Most of the proteins over-expressed in CMM were shown to have putative function in metabolism, of which seven were involved in amino acid transport and metabolism or lipid metabolism. PMID:19664283

  17. Complete Genome Sequence of the Marine, Chemolithoautotrophic, Ammonia-Oxidizing Bacterium Nitrosococcus oceani ATCC 19707

    SciTech Connect

    Klots, Martin G.; Arp, D J; Chain, Patrick S; El-Sheikh, Amal F.; Hauser, Loren John; Hommes, Norman G.; Larimer, Frank W; Malfatti, Stephanie; Norton, Jeanette M.; Poret-Peterson, Amisha T.; Vergez, Lisa; Ward, Bess B.

    2006-01-01

    The gammaproteobacterium Nitrosococcus oceani (ATCC 19707) is a gram-negative obligate chemolithoautotroph capable of extracting energy and reducing power from the oxidation of ammonia to nitrite. Sequencing and annotation of the genome revealed a single circular chromosome (3,481,691 bp; G+C content of 50.4%) and a plasmid (40,420 bp) that contain 3,052 and 41 candidate protein-encoding genes, respectively. The genes encoding proteins necessary for the function of known modes of lithotrophy and autotrophy were identified. Contrary to betaproteobacterial nitrifier genomes, the N. oceani genome contained two complete rrn operons. In contrast, only one copy of the genes needed to synthesize functional ammonia monooxygenase and hydroxylamine oxidoreductase, as well as the proteins that relay the extracted electrons to a terminal electron acceptor, were identified. The N. oceani genome contained genes for 13 complete two-component systems. The genome also contained all the genes needed to reconstruct complete central pathways, the tricarboxylic acid cycle, and the Embden-Meyerhof-Parnass and pentose phosphate pathways. The N. oceani genome contains the genes required to store and utilize energy from glycogen inclusion bodies and sucrose. Polyphosphate and pyrophosphate appear to be integrated in this bacterium's energy metabolism, stress tolerance, and ability to assimilate carbon via gluconeogenesis. One set of genes for type I ribulose-1,5-bisphosphate carboxylase/oxygenase was identified, while genes necessary for methanotrophy and for carboxysome formation were not identified. The N. oceani genome contains two copies each of the genes or operons necessary to assemble functional complexes I and IV as well as ATP synthase (one H+-dependent F0F1 type, one Na+-dependent V type).

  18. Multicopy Integration and Expression of Heterologous Genes in Methylobacterium extorquens ATCC 55366†

    PubMed Central

    Choi, Young J.; Bourque, Denis; Morel, Lyne; Groleau, Denis; Míguez, Carlos B.

    2006-01-01

    High-level expression of chromosomally integrated genes in Methylobacterium extorquens ATCC 55366 was achieved under the control of the strong M. extorquens AM1 methanol dehydrogenase promoter (PmxaF) using the mini-Tn7 transposon system. Stable maintenance and expression of the integrated genes were obtained in the absence of antibiotic selective pressure. Furthermore, using this technology, a multicopy integration protocol for M. extorquens was also developed. Chromosomal integration of one to five copies of the gene encoding the green fluorescent protein (gfp) was achieved. The multicopy-based expression system permitted expression of a preset number of gene copies. A unique specific Tn7 integration locus in the chromosome of M. extorquens, known as the Tn7 attachment site (attTn7 site), was identified. This single attTn7 site was identified in an intergenic region between glmS, which encodes the essential enzyme glucosamine-6-phosphate synthetase, and dhaT, which encodes 1,3-propanediol dehydrogenase. The fact that the integration event is site specific and the fact that the attTn7 site is a noncoding region of the chromosome make the mini-Tn7 transposon system very useful for insertion of target genes and subsequent expression. In all transformants tested, expression and segregation of the transforming gene were stable without generation of secondary mutations in the host. In this paper, we describe single and multicopy chromosome integration and stable expression of heterologous genes (bgl [β-galactosidase], est [esterase], and gfp [green fluorescent protein]) in M. extorquens. PMID:16391115

  19. Structural analysis of Clostridium acetobutylicum ATCC 824 glycoside hydrolase from CAZy family GH105.

    PubMed

    Germane, Katherine L; Servinsky, Matthew D; Gerlach, Elliot S; Sund, Christian J; Hurley, Margaret M

    2015-08-01

    Clostridium acetobutylicum ATCC 824 gene CA_C0359 encodes a putative unsaturated rhamnogalacturonyl hydrolase (URH) with distant amino-acid sequence homology to YteR of Bacillus subtilis strain 168. YteR, like other URHs, has core structural homology to unsaturated glucuronyl hydrolases, but hydrolyzes the unsaturated disaccharide derivative of rhamnogalacturonan I. The crystal structure of the recombinant CA_C0359 protein was solved to 1.6 Å resolution by molecular replacement using the phase information of the previously reported structure of YteR (PDB entry 1nc5) from Bacillus subtilis strain 168. The YteR-like protein is a six-α-hairpin barrel with two β-sheet strands and a small helix overlaying the end of the hairpins next to the active site. The protein has low primary protein sequence identity to YteR but is structurally similar. The two tertiary structures align with a root-mean-square deviation of 1.4 Å and contain a highly conserved active pocket. There is a conserved aspartic acid residue in both structures, which has been shown to be important for hydration of the C=C bond during the release of unsaturated galacturonic acid by YteR. A surface electrostatic potential comparison of CA_C0359 and proteins from CAZy families GH88 and GH105 reveals the make-up of the active site to be a combination of the unsaturated rhamnogalacturonyl hydrolase and the unsaturated glucuronyl hydrolase from Bacillus subtilis strain 168. Structural and electrostatic comparisons suggests that the protein may have a slightly different substrate specificity from that of YteR. PMID:26249707

  20. Mutational Studies of Putative Biosynthetic Genes for the Cyanobacterial Sunscreen Scytonemin in Nostoc punctiforme ATCC 29133

    PubMed Central

    Ferreira, Daniela; Garcia-Pichel, Ferran

    2016-01-01

    The heterocyclic indole-alkaloid scytonemin is a sunscreen found exclusively among cyanobacteria. An 18-gene cluster is responsible for scytonemin production in Nostoc punctiforme ATCC 29133. The upstream genes scyABCDEF in the cluster are proposed to be responsible for scytonemin biosynthesis from aromatic amino acid substrates. In vitro studies of ScyA, ScyB, and ScyC proved that these enzymes indeed catalyze initial pathway reactions. Here we characterize the role of ScyD, ScyE, and ScyF, which were logically predicted to be responsible for late biosynthetic steps, in the biological context of N. punctiforme. In-frame deletion mutants of each were constructed (ΔscyD, ΔscyE, and ΔscyF) and their phenotypes studied. Expectedly, ΔscyE presents a scytoneminless phenotype, but no accumulation of the predicted intermediaries. Surprisingly, ΔscyD retains scytonemin production, implying that it is not required for biosynthesis. Indeed, scyD presents an interesting evolutionary paradox: it likely originated in a duplication event from scyE, and unlike other genes in the operon, it has not been subjected to purifying selection. This would suggest that it is a pseudogene, and yet scyD is highly conserved in the scytonemin operon of cyanobacteria. ΔscyF also retains scytonemin production, albeit exhibiting a reduction of the production yield compared with the wild-type. This indicates that ScyF is not essential but may play an adjuvant role for scytonemin synthesis. Altogether, our findings suggest that these downstream genes are not responsible, as expected, for the late steps of scytonemin synthesis and we must look for those functions elsewhere. These findings are particularly important for biotechnological production of this sunscreen through heterologous expression of its genes in more tractable organisms. PMID:27242750