B.R. Mohapatra

Louisiana State University, Baton Rouge, Louisiana, United States

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Publications (31)46.41 Total impact

  • Bidyut R Mohapatra · Myron T La Duc
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    ABSTRACT: Due to their contribution to gastrointestinal and pulmonary disease, their ability to produce various deadly exotoxins, and their resistance to extreme temperature, pressure, radiation, and common chemical disinfecting agents, bacterial endospores of the Firmicutes phylum are a major concern for public and environmental health. In addition, the hardy and dormant nature of endospores renders them a particularly significant threat to the integrity of robotic extraterrestrial life-detection investigations. To prevent the contamination of critical surfaces with seemingly ubiquitous bacterial endospores, clean rooms maintained at exceedingly stringent cleanliness levels (i.e., fewer than 100,000 airborne particles per ft(3)) are used for surgical procedures, pharmaceutical processing and packaging, and fabrication and assembly of medical devices and spacecraft components. However, numerous spore-forming bacterial species have been reported to withstand typical clean room bioreduction strategies (e.g., UV lights, maintained humidity, paucity of available nutrients), which highlights the need for rapid and reliable molecular methods for detecting, enumerating, and monitoring the incidence of viable endospores. Robust means of evaluating and tracking spore burden not only provide much needed information pertaining to endospore ecophysiology in different environmental niches but also empower decontamination and bioreduction strategies aimed at sustaining the reliability and integrity of clean room environments. An overview of recent molecular advances in detecting and enumerating viable endospores, as well as the expanding phylogenetic diversity of pathogenic and clean room-associated spore-forming bacteria, ensues.
    No preview · Article · Aug 2013 · Applied Microbiology and Biotechnology
  • B.R. Mohapatra · O. Dinardo · W.D. Gould · D.W. Koren
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    ABSTRACT: Development of environmentally sustainable technologies for remediation of radionuclides is of paramount importance because of their long-term persistence in different ecological niches and acute toxic and teratogenic effects on human, terrestrial, and aquatic life. The radionuclides U(VI), Tc(VII), Pu(VI), and Np(V) are enzymatically reduced to environmentally benign U(IV), Tc(IV), Pu(IV), and Np(IV), respectively, by anaerobic microorganisms for the production of energy and/or as a process of detoxification for their survival. These anaerobic microorganisms produce the oxidoreductase class of enzymes for the metabolism of radionuclides. These microorganisms have potential applications for the in situ environmentally friendly mitigation of radionuclides in subsurface environments. Appropriate knowledge on the biochemical and genetic pathways of radionuclides reduction by microorganisms will not only provide information on the fate and dynamics of these compounds in subsurface geological environments but also help to implement best management practice(s) for immobilization of these toxic compounds in waste effluents generated by the mining and nuclear industries. This article describes the phylogenetic diversity of radionuclides-reducing microorganisms present in the environment, various enzymatic systems associated with the reduction of radionuclides, and identification of genes involved in the regulation of different enzymatic redox reactions.
    No preview · Article · Jan 2013
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    ABSTRACT: Thiocyanate and cyanide are formed during the processing of gold ores and the production of coke for steel production. Thiocyanate is also formed biologically from the detoxification of cyanide. Thiocyanate is less toxic than cyanide but more stable and thus more difficult to destroy. There are no direct regulatory requirements for the release of thiocyanate into the environment but a number of regulatory agencies have published guidelines for thiocyanate release. Several species of bacteria have been shown to degrade thiocyanate using different biochemical pathways. Some bacteria degrade thiocyanate autotrophically in order to obtain energy and other bacteria utilize thiocyanate as either a sulfur or nitrogen source. Various chemical and biological technologies have been proposed for the destruction of thiocyanate in industrial effluents. Biological systems varying in size from laboratory to full scale have been shown to successfully remove thiocyanate from both industrial and mining effluents. Additional research should be directed towards improving the understanding of the biochemistry of thiocyanate metabolism and scaling up technologies for thiocyanate degradation from laboratory to full scale.
    No preview · Article · Jul 2012 · Minerals Engineering
  • Bidyut R Mohapatra · Myron T La Duc
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    ABSTRACT: The survival of Bacillus pumilus SAFR-032 spores to standard industrial clean room sterilization practices necessitates the development of rapid molecular diagnostic tool(s) for detection and enumeration of viable bacterial spores in industrial clean room environments. This is of importance to maintaining the sterility of clean room processing products. This paper describes the effect of propidium monoazide (PMA) on fluorescence in situ hybridization (FISH) for detecting and enumerating B. pumilus SAFR-032 viable spores having been artificially encapsulated within poly(methylmethacrylate) (Lucite, Plexiglas) and released via an organic solvent (PolyGone-500). The results of the PMA-FISH experiments discussed herein indicate that PMA was able to permeate only the compromised coat layers of non-viable spores, identifying PMA treatment of bacterial spores prior to FISH analysis as a novel method for selecting out the fraction of the spore population that is non-viable from fluorescence detection. The ability of novel PMA-FISH to selectively distinguish and enumerate only the living spores present in a sample is of potential significance for development of improved strategies to minimize spore-specific microbial burden in a given environment.
    No preview · Article · Apr 2012 · Journal of microbiological methods
  • B.R. Mohapatra · O. Dinardo · W.D. Gould · D.W. Koren
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    ABSTRACT: Development of environmentally sustainable technologies for remediation of radionuclides is paramount because of their long-term persistence in different ecological niches and acute toxic and teratogenic effects on human, terrestrial, and aquatic life. The radionuclides U(VI), Tc(VII), Pu(VI), and Np(V) are enzymatically reduced to environmentally benign U(IV), Tc(IV), Pu(IV), and Np(IV), respectively, by anaerobic microorganisms for the production of energy and/or as a process of detoxification for their survival. These anaerobic microorganisms produce the oxidoreductase class of enzymes for the metabolism of radionuclides. These microorganisms have potential applications for the in situ environmentally friendly mitigation of radionuclides in subsurface environments. Appropriate knowledge on the biochemical and genetic pathways of radionuclides reduction by microorganisms will not only provide information on the fate and dynamics of these compounds in subsurface geological environments but also help to implement best management practice(s) for immobilization of these toxic compounds in waste effluents generated by the mining and nuclear industries. This article describes the phylogenetic diversity of radionuclides-reducing microorganisms present in the environment, various enzymatic systems associated with the reduction of radionuclides, and identification of genes involved in the regulation of different enzymatic redox reactions.
    No preview · Chapter · Dec 2011
  • Source
    Bidyut R Mohapatra · Myron T La Duc
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    ABSTRACT: Bacillus pumilus SAFR-032 spores originally isolated from the Jet Propulsion Laboratory spacecraft assembly facility clean room are extremely resistant to UV radiation, H(2)O(2), desiccation, chemical disinfection and starvation compared to spores of other Bacillus species. The resistance of B. pumilus SAFR-032 spores to standard industrial clean room sterilization practices is not only a major concern for medical, pharmaceutical and food industries, but also a threat to the extraterrestrial environment during search for life via spacecraft. The objective of the present study was to investigate the potential of Alexa-FISH (fluorescence in situ hybridization with Alexa Fluor® 488 labeled oligonucleotide) method as a molecular diagnostic tool for enumeration of multiple sterilant-resistant B. pumilus SAFR-032 spores artificially encapsulated in, and released via organic solvent from, a model polymeric material: poly(methylmethacrylate) (Lucite, Plexiglas). Plexiglas is used extensively in various aerospace applications and in medical, pharmaceutical and food industries. Alexa-FISH signals were not detected from spores via standard methods for vegetative bacterial cells. Optimization of a spore permeabilization protocol capitalizing on the synergistic action of proteinase-K, lysozyme, mutanolysin and Triton X-100 facilitated efficient spore detection by Alexa-FISH microscopy. Neither of the Alexa-probes tested gave rise to considerable levels of Lucite- or solvent-associated background autofluorescence, demonstrating the immense potential of Alexa-FISH for rapid quantification of encapsulated B. pumilus SAFR-032 spores released from poly(methylmethacrylate).
    Preview · Article · Dec 2011 · Microbiology and Immunology
  • Bidyut R. Mohapatra · W. Douglas Gould · Orlando Dinardo · David W. Koren
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    ABSTRACT: The negative impact of acid mine drainage (AMD) on public and environmental health by degrading the aquatic and terrestrial ecosystem with a drastic decrease in pH and elevated levels of toxic heavy metals, metalloids and radionuclides necessitate the development of environmentally sustainable technologies to remediate AMD. The development of appropriate strategies for controlling and/or abating the detrimental effects of AMD in natural and mining environments primarily depends on the diversity and compositions of the local acidophilic microbial communities (those which can grow at pH⩽3) which catalyze the reactions of AMD by production of sulfuric acid and ferric iron. Robust method(s) to track the AMD-promoting microbial communities will not only provide information about their ecophysiological role in extreme environments but also help sustain the reliability of remediation technologies. This paper provides an overview on the phylogenetic diversity of prokaryotes present in AMD-impacted environments, and different molecular methods that have been used to track the diversity of these acidophiles. Additionally, the high-throughput methods (metagenomics, metaproteomics and microarrays) that link prokaryotic phylogeny to their function in AMD systems are also discussed.
    No preview · Article · Jul 2011 · Minerals Engineering
  • B.R. Mohapatra · W. Douglas Gould · O. Dinardo · D.W. Koren
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    ABSTRACT: The bioleaching microbial communities comprised of sulfur-and iron-oxidizing bacteria and archaea have attracted significant industrial interest as potential biocatalysts in eco-friendly recovery of base and precious metals, including Cu, Zn, Ni, Co, Ag and Au from low-grade sulfide ores, and in bioremediation of toxic sulfide-and heavy metals-containing industrial waste effluents. Considerable efforts have been devoted in the identification of the mechanism of enzymatic regulatory pathways and the gene(s) encoding the enzymes responsible for catalysis of iron and inorganic sulfur compounds. The recognition that >99% of microorganisms in most environments cannot be cultured by standard methods stimulated the development of metagenomics: the genomic analysis of uncultured microorganisms. This paper provides an overview on the diversity of microorganisms involved in the bioleaching processes, and the advantages of application of metagenomics and directed evolution approaches for efficient utilization of bioleaching microorganisms.
    No preview · Article · Feb 2011
  • B.R. Mohapatra · K. Fukami
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    ABSTRACT: Recently with advances in biochemical and molecular microbiological techniques, there has been a growing interest to assess the numerical and functional significance of microorganisms in different ecosystems of our planet. The marine biosphere consists of diverse assemblages of microorganisms with extreme variations in pressure, salinity and temperature. Heterotrophic nanoflagellates (HNF) with a size range from 2 to 20 μm are ubiquitous protozoan communities in marine environments. HNF are considered as primary consumers of bacteria and regulate the bacterial density and the phenotypic and genotypic composition of bacteria by selective grazing in marine environments. HNF mediated grazing is also an important ecological process in marine materials cycling by the production of dissolved organic and dissolved inorganic matter. Despite the pivotal role of HNF in marine microbial food web, the ecophysiological role of HNF is mostly neglected. In this chapter, an overview of the diversity and distribution of HNF in marine environments, seasonal variation of HNF grazing rates on bacteria, the efficacy of HNF as nutrient generators, the nutritional ecology of HNF, mechanism responsible for food bacterial selection by HNF and their contribution to the enzyme pool during selective feeding on bacteria in marine environments is discussed.
    No preview · Article · Feb 2011
  • Bidyut R. Mohapatra · Orlando Dinardo · W. Douglas Gould · David W. Koren
    [Show abstract] [Hide abstract]
    ABSTRACT: Development of environmentally sustainable technologies for remediation of radionuclides is paramount because of their long-term persistence in different ecological niches and acute toxic and teratogenic effects on human, terrestrial and aquatic life. The radionuclides U (VI), Tc (VII), Pu (VI) and Np (V) are enzymatically reduced to environmentally benign U (IV), Tc (IV), Pu (IV) and Np (IV), respectively by anaerobic microorganisms for production of energy and/or as a process of detoxification for their survival. These anaerobic microorganisms produce the oxidoreductase class of enzymes for the metabolism of radionuclides. These microorganisms have potential applications for the in situ environmentally friendly mitigation of radionuclides in subsurface environments. Appropriate knowledge on the biochemical and genetic pathways of radionuclides reduction by microorganisms will not only provide information on the fate and dynamics of these compounds in subsurface geological environments but also help to implement best management practice(s) for immobilization of these toxic compounds in waste effluents generated by the mining and nuclear industries. This review describes the phylogenetic diversity of radionuclides-reducing microorganisms present in the environment, various enzymatic systems associated with the reduction of radionuclides, and identification of genes involved in regulation of different enzymatic redox reactions.
    No preview · Article · Jul 2010 · Minerals Engineering
  • B.R. Mohapatra · W.D. Gould · O. Dinardo · D.W. Koren
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    ABSTRACT: Sulfate-reducing microorganisms (SRM) comprising of anaerobic bacteria and anaerobic archaea are an integral part of the global sulfur and carbon cycle for dissimilatory reduction of sulfate using sulfate as electron acceptor for the degradation of organic compounds with concomitant production of hydrogen sulfide. SRM are known to be ubiquitous in natural and engineering environments, including in the methanogenic and sulfidogenic sludge generated by municipal and industrial wastewater treatment facilities. Additionally, SRM are responsible for ca. 50% of the organic matter mineralization in wastewater treatment systems. SRM are detrimental to the safety, reliability and integrity of wastewater treatment facilities, and to the public and environmental health because hydrogen sulfide is highly corrosive, neurotoxic and malodorous. However, SRM have attracted significant industrial interest as potential biocatalysts for environmentally friendly remediation of acid mine and rock drainage, removal and reuse of sulfur compounds from waste effluents and off gases, recovery of heavy metals from wastewater and sludge, and biotransformation of petroleum- and hydrocarbon-containing sludge. Considerable efforts have been devoted for development of robust techniques to provide an early detection of SRM occurrence, to identify novel strains for bioremediation, and/or to evaluate their ecophysiological roles in the natural and engineering environments. This chapter provides an overview on the distribution and phylogenetic diversity of microorganisms associated with dissimilatory sulfate reduction, and the recent development of techniques used for the characterization of SRM in natural and industrial environments, including in the process of biological remediation of toxic wastewater and sludge.
    No preview · Article · Apr 2009
  • B.R. Mohapatra · W. Douglas Gould · O. Dinardo · D.W. Koren
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    ABSTRACT: The acidophilic microorganisms (defined as those which can grow at pH ≤3) play a major role in the bioleaching processing of low grade ores for extraction of base and precious metals, including Cu, Zn, Ni, Co, Ag and Au. The bioleaching microorganisms act as the biocatalyst in the oxidation and dissolution of metal sulfide ores by the production of sulfuric acid and ferric ions. The application of bioleaching microorganisms in ore processing has several distinct advantages over conventional mineral processing methods. Microbial extraction processes are believed to be ecofriendly methods owing to the requirement of lesser amounts of energy compared to roasting or smelting, and no production of sulfur dioxide or other gases detrimental to the environment. Bioleaching microorganisms have also attracted significant industrial interest for treatment of toxic heavy metals-and sulfide-containing industrial waste effluents. On the other hand, these microorganisms have a negative impact on public and environmental health with the generation of highly toxic acid mine drainage (AMD). AMD is generated by the subsurface and the surface (open pit) mining of metal ores and coal with the resulting exposure of sulfide minerals to air and water. AMD degrades the quality of surface and groundwater intended for drinking, recreation, crop irrigation and aquaculture with elevated levels of sulfate, and toxic heavy metals and metalloids. In order to improve the mineral oxidizing activity of bioleaching microorganisms and to inhibit the production of AMD, it is essential to develop robust genotypic tools for speciation as well as for determination of the biological activities of bioleaching microorganisms. In this chapter, we have provided an overview of the molecular techniques including different genomic fingerprinting methods that have been used for the characterization of bioleaching microorganisms.
    No preview · Article · Jan 2009
  • Bidyut R. Mohapatra · W. Douglas Gould · Orlando Dinardo · David W. Koren
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    ABSTRACT: Inorganic sulfur compounds are oxidized mostly to sulfate by microorganisms belonging to the bacteria and archaea domains. These microorganisms produce different types of enzymes, e. g., oxidoreductases and hydrolases for the metabolism of inorganic sulfur compounds. These versatile biocatalysts have potential biotechnological applications in different fields including biohydrometallurgical processes for recovering precious heavy metals and also for bioremediation of sulfides in industrial waste effluents. Appropriate knowledge on the enzymatic pathways of inorganic sulfur compounds oxidation will help to tailor the catalytic properties of these microorganisms so that they are optimal not only for a given reaction but also in the context of harsh industrial processes. This review describes the distribution of inorganic sulfur compound-oxidizing microorganisms, various enzymatic systems associated with sulfur metabolism, and identification of the gene(s) responsible for catalysis of different enzymatic reactions.
    No preview · Article · Nov 2008 · CLEAN - Soil Air Water
  • Bidyut R Mohapatra · Klaas Broersma · Asit Mazumder
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    ABSTRACT: Determination of the non-point sources of fecal pollution is essential for the assessment of potential public health risk and development of appropriate management practices for prevention of further contamination. Repetitive extragenic palindromic-PCR coupled with (GTG)(5) primer [(GTG)(5)-PCR] was performed on 573 Escherichia coli isolates obtained from the feces of poultry (chicken, duck and turkey) and free-living (Canada goose, hawk, magpie, seagull and songbird) birds to evaluate the efficacy of (GTG)(5)-PCR genomic fingerprinting in the prediction of the correct source of fecal pollution. A discriminant analysis with the jack-knife algorithm of (GTG)(5)-PCR DNA fingerprints revealed that 95%, 94.1%, 93.2%, 84.6%, 79.7%, 76.7%, 75.3% and 70.7% of magpie, hawk, turkey, seagull, Canada goose, chicken, duck and songbird fecal E. coli isolates classified into the correct host source, respectively. The results of this study indicate that (GTG)(5)-PCR can be considered to be a complementary molecular tool for the rapid determination of E. coli isolates identity and tracking the non-point sources of fecal pollution.
    No preview · Article · May 2008 · International journal of medical microbiology: IJMM
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    B R Mohapatra · A Mazumder
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    ABSTRACT: Development of efficient techniques to discriminate the sources of E. coli in aquatic environments is essential to improve the surveillance of fecal pollution indicators, to develop strategies to identify the sources of fecal contamination, and to implement appropriate management practices to minimize gastrointestinal disease transmission. In this study the robustness of five different rep-PCR methods, such as REP-PCR, ERIC-PCR, ERIC2-PCR, BOX-PCR and (GTG)(5)-PCR were evaluated to discriminate 271 E. coli strains isolated from two watersheds (Lakelse Lake and Okanagan Lake) located in British Columbia, Canada. Cluster analysis of (GTG)(5)-PCR, BOX-PCR, REP-PCR, ERIC-PCR and ERIC2-PCR profiles of 271 E. coli revealed 43 clusters, 35 clusters, 28 clusters, 23 clusters and 14 clusters, respectively. The discriminant analysis of rep-PCR genomic fingerprints of 271 E. coli isolates yielded an average rate of correct classification (watershed-specific) of 86.8%, 82.3%, 78.4%, 72.6% and 55.8% for (GTG)(5)-PCR, BOX-PCR, REP-PCR, ERIC-PCR and ERIC2-PCR, respectively. Based on the results of cluster analysis and discriminant function analysis, (GTG)(5)-PCR was found to be the most robust molecular tool for differentiation of E. coli populations in aquatic environments.
    Preview · Article · Feb 2008 · Water Science & Technology
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    ABSTRACT: In order to determine the impact of immobilization on biocatalytic efficacy of sulfide oxidase, the kinetic and thermodynamic properties of native and DEAE-cellulose immobilized sulfide oxidase from Arthrobacter species FR-3 were evaluated. Immobilization increased the catalytic efficiency of sulfide oxidase by producing a lower Michaelis-Menten constant (Km) and a higher rate of catalysis (Vmax) at different temperatures. The first-order kinetic analysis of thermal denaturation demonstrated that the values of enthalpy (delta H*d) and entropy (delta S*d) of immobilized sulfide oxidase were lower than the native enzyme, confirming the thermal stabilization of sulfide oxidase by immobilization. The delta H*d and delta S*d of the immobilized enzyme at 35 degrees C were 138.07 kJ/mol and 122.04 J/K/mol, respectively. These results suggest that immobilization made the sulfide oxidase from Arthrobacter sp. FR-3 thermodynamically more efficient for catalysis of sulfide oxidation.
    No preview · Article · Feb 2008 · Preparative Biochemistry & Biotechnology
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    Bidyut R Mohapatra · Klaas Broersma · Asit Mazumder
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    ABSTRACT: The development of a methodology to identify the origin of fecal pollution is important both for assessing the degree of risk posed to public health and for developing strategies to mitigate the environmental loading of pathogens associated with waterborne disease transmission. Five rep-PCR genomic fingerprinting methods, such as rep-PCR, enterobacterial repetitive intergenic consensus (ERIC)-PCR, ERIC2-PCR, BOX-PCR and (GTG)(5)-PCR, were assessed for their potential in differentiation of 232 fecal Escherichia coli isolates obtained from humans, poultry (chicken, duck and turkey) and wild birds (Canada goose and gull). Based on the results of cluster analysis and discriminant function analysis, (GTG)(5)-PCR was found to be the most suitable method for molecular typing of fecal E. coli, followed by BOX-PCR, REP-PCR, ERIC-PCR and ERIC2-PCR. A discriminant function analysis of (GTG)(5)-PCR fingerprints showed that 94.1%, 79.8%, 80.5%, 74.4%, 86.7% and 88.6% of turkey, chicken, duck, Canada goose, gull and human E. coli isolates were classified into the correct host group, respectively. Subsequently, (GTG)(5)-PCR was tested for its ability to track the origin of 113 environmental E. coli isolated from natural pond water. In conclusion, the (GTG)(5)-PCR genomic fingerprinting method can be considered as a promising genotypic tool for epidemiological surveillance of fecal pollution in aquatic environments.
    Preview · Article · Jan 2008 · FEMS Microbiology Letters
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    B. R. Mohapatra · K. Fukami
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    ABSTRACT: Heterotrophe Nanoflagellaten (HNF) in der Größenordnung von 2 bis 20 μm bilden weitverbreitete einzellige Zooplanktongemeinschaften in aquatischen Lebensräumen. HNF werden als die prinzipiellen Weidegänger auf Bakterien angesehen und spielen eine wesentliche Rolle im Kreislauf organischer Stoffe. Bis heute gibt es wenig Informationen über das chemisch vermittelte artspezifische Fraßverhalten mariner HNF. In dieser Untersuchung wurden die chemosensorischen Reaktionen des vielseitigen marinen HNF Jakoba libera Stamms 5(2) auf die Beutebakterien Pseudomonas sp., Flavobacterium sp. und Aeromonas sp. mit der Kapillarpipettentechnik bei 20 °C im Dunkeln getestet. Die chemosensorische Anziehung war am größten bei dem Beutebakterium Pseudomonas sp., gefolgt von Flavobacterium sp. und Aeromonas sp.. Die chemische Analyse der Komponenten der Bakterienoberfläche von Pseudomonas sp. wiesen darauf hin, dass die chemosensorischen Komponenten ein hohes Molekulargewicht (>25 kiloDalton) und eine Halbwertszeit von 15 min bei 40 °C hatten. Diese Variation in den chemosensorischen Reaktionen von Jakoba libera 5(2) auf verschiedene Beutebakterien stützt die Hypothese, dass HNF chemosensorische Mechanismen nutzen, um ihre Beutebakterien in marinen Umwelten zu finden.
    Preview · Article · Sep 2007 · Basic and Applied Ecology
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    ABSTRACT: Response surface methodology was used to develop a fermentation medium for the enhanced biosynthesis of a novel sulfide oxidase by Arthrobacter species strain FR-3. The interactive effect of the medium components – such as glucose as the carbon source, and tryptone and yeast extract as the nitrogen source – was evaluated by a 23-factorial central composite statistical design. Glucose and yeast extract were found to be the more influential medium constituents compared to tryptone since they had lower coefficients of linear effect, P-values (< 0.02). The optimal fermentation medium components for the enhanced production of sulfide oxidase were recorded as glucose (8.98 g/L), tryptone (10.62 g/L) and yeast extract (7.3 g/L). Optimization of the medium constituents increased the experimental enzyme yield by 54 % compared to the unoptimized medium. This is the first report on the overproduction of sulfide oxidase by using response surface methodology.
    No preview · Article · Jun 2007 · Engineering in Life Sciences
  • Source
    Bidyut R Mohapatra · Klaas Broersma · Rick Nordin · Asit Mazumder
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    ABSTRACT: The objective of this study was to investigate the potential of repetitive extragenic palindromic anchored polymerase chain reaction (rep-PCR) in differentiating fecal Escherichia coli isolates of human, domestic- and wild-animal origin that might be used as a molecular tool to identify the possible source(s) of fecal pollution of source water. A total of 625 fecal E. coli isolates of human, 3 domestic- (cow, dog and horse) and 7 wild-animal (black bear, coyote, elk, marmot, mule deer, raccoon and wolf) species were characterized by rep-PCR DNA fingerprinting technique coupled with BOX A1R primer and discriminant analysis. Discriminant analysis of rep-PCR DNA fingerprints of fecal E. coli isolates from 11 host sources revealed an average rate of correct classification of 79.89%, and 84.6%, 83.8%, 83.3%, 82.5%, 81.6%, 80.8%, 79.8%, 79.3%, 77.4%, 73.2% and 63.6% of elk, human, marmot, mule deer, cow, coyote, raccoon, horse, dog, wolf and black bear fecal E. coli isolates were assigned to the correct host source. These results suggest that rep-PCR DNA fingerprinting procedures can be used as a source tracking tool for detection of human- as well as animal-derived fecal contamination of water.
    Full-text · Article · Feb 2007 · Microbiology and Immunology

Publication Stats

396 Citations
46.41 Total Impact Points

Institutions

  • 2013
    • Louisiana State University
      • Department of Biological Sciences
      Baton Rouge, Louisiana, United States
  • 2012
    • University of South Alabama
      Mobile, Alabama, United States
  • 2011-2012
    • California Institute of Technology
      Pasadena, California, United States
  • 2007-2011
    • Natural Resources Canada
      Ottawa, Ontario, Canada
  • 2006-2008
    • University of Victoria
      • Department of Biology
      Victoria, British Columbia, Canada
  • 2002-2005
    • Kochi University
      • Faculty of Agriculture
      Kōchi-shi, Kochi-ken, Japan