The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Kasthuri Venkateswaran - One of the best experts on this subject based on the ideXlab platform.
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Bacillus Pumilus safr 032 genome revisited sequence update and re annotation
PLOS ONE, 2016Co-Authors: Victor G Stepanov, Madhan R Tirumalai, Saied Montazari, Aleksandra Checinska, Kasthuri Venkateswaran, George E FoxAbstract:Bacillus Pumilus strain SAFR-032 is a non-pathogenic spore-forming bacterium exhibiting an anomalously high persistence in bactericidal environments. In its dormant state, it is capable of withstanding doses of ultraviolet (UV) radiation or hydrogen peroxide, which are lethal for the vast majority of microorganisms. This unusual resistance profile has made SAFR-032 a reference strain for studies of bacterial spore resistance. The complete genome sequence of B. Pumilus SAFR-032 was published in 2007 early in the genomics era. Since then, the SAFR-032 strain has frequently been used as a source of genetic/genomic information that was regarded as representative of the entire B. Pumilus species group. Recently, our ongoing studies of conservation of gene distribution patterns in the complete genomes of various B. Pumilus strains revealed indications of misassembly in the B. Pumilus SAFR-032 genome. Synteny-driven local genome resequencing confirmed that the original SAFR-032 sequence contained assembly errors associated with long sequence repeats. The genome sequence was corrected according to the new findings. In addition, a significantly improved annotation is now available. Gene orders were compared and portions of the genome arrangement were found to be similar in a wide spectrum of Bacillus strains.
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Survival of Bacillus Pumilus Spores for a Prolonged Period of Time in Real Space Conditions
Astrobiology, 2012Co-Authors: Parag Vaishampayan, Elke Rabbow, Gerda Horneck, Kasthuri VenkateswaranAbstract:Abstract To prevent forward contamination and maintain the scientific integrity of future life-detection missions, it is important to characterize and attempt to eliminate terrestrial microorganisms associated with exploratory spacecraft and landing vehicles. Among the organisms isolated from spacecraft-associated surfaces, spores of Bacillus Pumilus SAFR-032 exhibited unusually high resistance to decontamination techniques such as UV radiation and peroxide treatment. Subsequently, B. Pumilus SAFR-032 was flown to the International Space Station (ISS) and exposed to a variety of space conditions via the European Technology Exposure Facility (EuTEF). After 18 months of exposure in the EXPOSE facility of the European Space Agency (ESA) on EuTEF under dark space conditions, SAFR-032 spores showed 10–40% survivability, whereas a survival rate of 85–100% was observed when these spores were kept aboard the ISS under dark simulated martian atmospheric conditions. In contrast, when UV (>110 nm) was applied on SAF...
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recurrent isolation of hydrogen peroxide resistant spores of Bacillus Pumilus from a spacecraft assembly facility
Astrobiology, 2005Co-Authors: Michael Kempf, Fei Chen, Roger Kern, Kasthuri VenkateswaranAbstract:While the microbial diversity of a spacecraft assembly facility at the Jet Propulsion Laboratory (Pasadena, CA) was being monitored, H2O2-resistant bacterial strains were repeatedly isolated from various surface locations. H2O2 is a possible sterilant for spacecraft hardware because it is a low-temperature process and compatible with various modern-day spacecraft materials, electronics, and components. Both conventional biochemical testing and molecular analyses identified these strains as Bacillus Pumilus. This Bacillus species was found in both unclassified (entrance floors, anteroom, and air-lock) and classified (floors, cabinet tops, and air) locations. Both vegetative cells and spores of several B. Pumilus isolates were exposed to 5% liquid H2O2 for 60 min. Spores of each strain exhibited higher resistance than their respective vegetative cells to liquid H2O2. Results indicate that the H2O2 resistance observed in both vegetative cells and spores is strain-specific, as certain B. Pumilus strains were ...
P Prema - One of the best experts on this subject based on the ideXlab platform.
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production of cellulase free endoxylanase from novel alkalophilic thermotolerent Bacillus Pumilus by solid state fermentation and its application in wastepaper recycling
Bioresource Technology, 2007Co-Authors: Asha C Poorna, P PremaAbstract:The present study aimed at optimization of culture condition for the enhanced production of extra cellular thermostable cellulase-free xylanase from Bacillus Pumilus by solid-state fermentation. Batch studies were carried out to evaluate various agro-industrial residues such as rice bran, rice husk, rice straw, sawdust, coconut pith, sugarcane bagasse and wheat bran for enzyme production by the bacterial culture. The endoxylanase production was highest on wheat bran media (5582 U/gds), which was enhanced 3.8-fold (21,431 U/gds) by optimization of cultivation conditions. The enzymatic extracts was used in mixed wastepaper recycling, which resulted in a considerable improvement of the paper strength with high drainage and easy drying up. The results of enzyme application with recycled paper clearly indicated that the effective use of enzymes in fiber separation could reduce the cost of carton paper production.
George E Fox - One of the best experts on this subject based on the ideXlab platform.
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Bacillus Pumilus safr 032 genome revisited sequence update and re annotation
PLOS ONE, 2016Co-Authors: Victor G Stepanov, Madhan R Tirumalai, Saied Montazari, Aleksandra Checinska, Kasthuri Venkateswaran, George E FoxAbstract:Bacillus Pumilus strain SAFR-032 is a non-pathogenic spore-forming bacterium exhibiting an anomalously high persistence in bactericidal environments. In its dormant state, it is capable of withstanding doses of ultraviolet (UV) radiation or hydrogen peroxide, which are lethal for the vast majority of microorganisms. This unusual resistance profile has made SAFR-032 a reference strain for studies of bacterial spore resistance. The complete genome sequence of B. Pumilus SAFR-032 was published in 2007 early in the genomics era. Since then, the SAFR-032 strain has frequently been used as a source of genetic/genomic information that was regarded as representative of the entire B. Pumilus species group. Recently, our ongoing studies of conservation of gene distribution patterns in the complete genomes of various B. Pumilus strains revealed indications of misassembly in the B. Pumilus SAFR-032 genome. Synteny-driven local genome resequencing confirmed that the original SAFR-032 sequence contained assembly errors associated with long sequence repeats. The genome sequence was corrected according to the new findings. In addition, a significantly improved annotation is now available. Gene orders were compared and portions of the genome arrangement were found to be similar in a wide spectrum of Bacillus strains.
Asha C Poorna - One of the best experts on this subject based on the ideXlab platform.
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production of cellulase free endoxylanase from novel alkalophilic thermotolerent Bacillus Pumilus by solid state fermentation and its application in wastepaper recycling
Bioresource Technology, 2007Co-Authors: Asha C Poorna, P PremaAbstract:The present study aimed at optimization of culture condition for the enhanced production of extra cellular thermostable cellulase-free xylanase from Bacillus Pumilus by solid-state fermentation. Batch studies were carried out to evaluate various agro-industrial residues such as rice bran, rice husk, rice straw, sawdust, coconut pith, sugarcane bagasse and wheat bran for enzyme production by the bacterial culture. The endoxylanase production was highest on wheat bran media (5582 U/gds), which was enhanced 3.8-fold (21,431 U/gds) by optimization of cultivation conditions. The enzymatic extracts was used in mixed wastepaper recycling, which resulted in a considerable improvement of the paper strength with high drainage and easy drying up. The results of enzyme application with recycled paper clearly indicated that the effective use of enzymes in fiber separation could reduce the cost of carton paper production.
Victor G Stepanov - One of the best experts on this subject based on the ideXlab platform.
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Bacillus Pumilus safr 032 genome revisited sequence update and re annotation
PLOS ONE, 2016Co-Authors: Victor G Stepanov, Madhan R Tirumalai, Saied Montazari, Aleksandra Checinska, Kasthuri Venkateswaran, George E FoxAbstract:Bacillus Pumilus strain SAFR-032 is a non-pathogenic spore-forming bacterium exhibiting an anomalously high persistence in bactericidal environments. In its dormant state, it is capable of withstanding doses of ultraviolet (UV) radiation or hydrogen peroxide, which are lethal for the vast majority of microorganisms. This unusual resistance profile has made SAFR-032 a reference strain for studies of bacterial spore resistance. The complete genome sequence of B. Pumilus SAFR-032 was published in 2007 early in the genomics era. Since then, the SAFR-032 strain has frequently been used as a source of genetic/genomic information that was regarded as representative of the entire B. Pumilus species group. Recently, our ongoing studies of conservation of gene distribution patterns in the complete genomes of various B. Pumilus strains revealed indications of misassembly in the B. Pumilus SAFR-032 genome. Synteny-driven local genome resequencing confirmed that the original SAFR-032 sequence contained assembly errors associated with long sequence repeats. The genome sequence was corrected according to the new findings. In addition, a significantly improved annotation is now available. Gene orders were compared and portions of the genome arrangement were found to be similar in a wide spectrum of Bacillus strains.
