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Sample records for cellulolytic thermophile acidothermus

  1. Complete genome of the cellulolytic thermophile Acidothermus cellulolyticus 11B provides insights into its ecophysiological and evolutionary adaptations

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Gary [Los Alamos National Laboratory; Detter, Chris [Los Alamos National Laboratory; Bruce, David [Los Alamos National Laboratory; Challacome, Jean F [Los Alamos National Laboratory; Brettin, Thomas S [Los Alamos National Laboratory; Barabote, Ravi D [UC DAVIS; Leu, David [UC DAVIS; Normand, Philippe [CNRS, UNIV LYON; Necsula, Anamaria [CNRS, UNIV LYON; Daubin, Vincent [CNRS, UNIV LYON; Medigue, Claudine [CNRS/GENOSCOPE; Adney, William S [NREL; Xu, Xin C [UC DAVIS; Lapidus, Alla [DOE JOINT GENOME INST.; Pujic, Pierre [CNRS, UNIV LYON; Richardson, Paul [DOE JOINT GENOME INST; Berry, Alison M [UC DAVIS

    2008-01-01

    We present here the complete 2.4 MB genome of the actinobacterial thermophile, Acidothermus cellulolyticus lIB, that surprisingly reveals thermophilic amino acid usage in only the cytosolic subproteome rather than its whole proteome. Thermophilic amino acid usage in the partial proteome implies a recent, ongoing evolution of the A. cellulolyticus genome since its divergence about 200-250 million years ago from its closest phylogenetic neighbor Frankia, a mesophilic plant symbiont. Differential amino acid usage in the predicted subproteomes of A. cellulolyticus likely reflects a stepwise evolutionary process of modern thermophiles in general. An unusual occurrence of higher G+C in the non-coding DNA than in the transcribed genome reinforces a late evolution from a higher G+C common ancestor. Comparative analyses of the A. cellulolyticus genome with those of Frankia and other closely-related actinobacteria revealed that A. cellulolyticus genes exhibit reciprocal purine preferences at the first and third codon positions, perhaps reflecting a subtle preference for the dinucleotide AG in its mRNAs, a possible adaptation to a thermophilic environment. Other interesting features in the genome of this cellulolytic, hot-springs dwelling prokaryote reveal streamlining for adaptation to its specialized ecological niche. These include a low occurrence of pseudogenes or mobile genetic elements, a flagellar gene complement previously unknown in this organism, and presence of laterally-acquired genomic islands of likely ecophysiological value. New glycoside hydrolases relevant for lignocellulosic biomass deconstruction were identified in the genome, indicating a diverse biomass-degrading enzyme repertoire several-fold greater than previously characterized, and significantly elevating the industrial value of this organism.

  2. Complete genome of the cellulolytic thermophile Acidothermus cellulolyticus 11B provides insights into its ecophysiological and evolutionary adaptations

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Gary [Los Alamos National Laboratory; Detter, John C [Los Alamos National Laboratory; Bruce, David C [Los Alamos National Laboratory; Challacombe, Jean F [Los Alamos National Laboratory; Brettin, Thomas S [Los Alamos National Laboratory; Necsulea, Anamaria [UNIV LYON; Daubin, Vincent [UNIV LYON; Medigue, Claudine [GENOSCOPE; Adney, William S [NREL; Xu, Xin C [UC DAVIS; Lapidus, Alla [JGI; Pujic, Pierre [UNIV LYON; Berry, Alison M [UC DAVIS; Barabote, Ravi D [UC DAVIS; Leu, David [UC DAVIS; Normand, Phillipe [UNIV LYON

    2009-01-01

    We present here the complete 2.4 MB genome of the actinobacterial thermophile, Acidothermus cellulolyticus 11B, that surprisingly reveals thermophilic amino acid usage in only the cytosolic subproteome rather than its whole proteome. Thermophilic amino acid usage in the partial proteome implies a recent, ongoing evolution of the A. cellulolyticus genome since its divergence about 200-250 million years ago from its closest phylogenetic neighbor Frankia, a mesophilic plant symbiont. Differential amino acid usage in the predicted subproteomes of A. cellulolyticus likely reflects a stepwise evolutionary process of modern thermophiles in general. An unusual occurrence of higher G+C in the non-coding DNA than in the transcribed genome reinforces a late evolution from a higher G+C common ancestor. Comparative analyses of the A. cellulolyticus genome with those of Frankia and other closely-related actinobacteria revealed that A. cellulolyticus genes exhibit reciprocal purine preferences at the first and third codon positions, perhaps reflecting a subtle preference for the dinucleotide AG in its mRNAs, a possible adaptation to a thermophilic environment. Other interesting features in the genome of this cellulolytic, hot-springs dwelling prokaryote reveal streamlining for adaptation to its specialized ecological niche. These include a low occurrence of pseudo genes or mobile genetic elements, a flagellar gene complement previously unknown in this organism, and presence of laterally-acquired genomic islands of likely ecophysiological value. New glycoside hydrolases relevant for lignocellulosic biomass deconstruction were identified in the genome, indicating a diverse biomass-degrading enzyme repertoire several-fold greater than previously characterized, and significantly elevating the industrial value of this organism.

  3. Complete genome of the cellyloytic thermophile Acidothermus cellulolyticus 11B provides insights into its ecophysiological and evloutionary adaptations

    Energy Technology Data Exchange (ETDEWEB)

    Barabote, Ravi D.; Xie, Gary; Leu, David H.; Normand, Philippe; Necsulea, Anamaria; Daubin, Vincent; Medigue, Claudine; Adney, William S.; Xu,Xin Clare; Lapidus, Alla; Detter, Chris; Pujic, Petar; Bruce, David; Lavire, Celine; Challacombe, Jean F.; Brettin, Thomas S.; Berry, Alison M.

    2009-01-01

    We present here the complete 2.4 Mb genome of the cellulolytic actinobacterial thermophile, Acidothermus cellulolyticus 11B. New secreted glycoside hydrolases and carbohydrate esterases were identified in the genome, revealing a diverse biomass-degrading enzyme repertoire far greater than previously characterized, and significantly elevating the industrial value of this organism. A sizable fraction of these hydrolytic enzymes break down plant cell walls and the remaining either degrade components in fungal cell walls or metabolize storage carbohydrates such as glycogen and trehalose, implicating the relative importance of these different carbon sources. A novel feature of the A. cellulolyticus secreted cellulolytic and xylanolytic enzymes is that they are fused to multiple tandemly arranged carbohydrate binding modules (CBM), from families 2 and 3. Interestingly, CBM3 was found to be always N-terminal to CBM2, suggesting a functional constraint driving this organization. While the catalytic domains of these modular enzymes are either diverse or unrelated, the CBMs were found to be highly conserved in sequence and may suggest selective substrate-binding interactions. For the most part, thermophilic patterns in the genome and proteome of A. cellulolyticus were weak, which may be reflective of the recent evolutionary history of A. cellulolyticus since its divergence from its closest phylogenetic neighbor Frankia, a mesophilic plant endosymbiont and soil dweller. However, ribosomal proteins and non-coding RNAs (rRNA and tRNAs) in A. cellulolyticus showed thermophilic traits suggesting the importance of adaptation of cellular translational machinery to environmental temperature. Elevated occurrence of IVYWREL amino acids in A. cellulolyticus orthologs compared to mesophiles, and inverse preferences for G and A at the first and third codon positions also point to its ongoing thermoadaptation. Additional interesting features in the genome of this cellulolytic, hot

  4. Characterization of cellulolytic enzymes and bioH2 production from anaerobic thermophilic Clostridium sp. TCW1.

    Science.gov (United States)

    Lo, Yung-Chung; Huang, Chi-Yu; Cheng, Chieh-Lun; Lin, Chiu-Yue; Chang, Jo-Shu

    2011-09-01

    A thermophilic anaerobic bacterium Clostridium sp. TCW1 was isolated from dairy cow dung and was used to produce hydrogen from cellulosic feedstock. Extracellular cellulolytic enzymes produced from TCW1 strain were identified as endoglucanases (45, 53 and 70 kDa), exoglucanase (70 kDa), xylanases (53 and 60 kDa), and β-glucosidase (45 kDa). The endoglucanase and xylanase were more abundant. The optimal conditions for H2 production and enzyme production of the TCW1 strain were the same (60 °C, initial pH 7, agitation rate of 200 rpm). Ten cellulosic feedstock, including pure or natural cellulosic materials, were used as feedstock for hydrogen production by Clostridium strain TCW1 under optimal culture conditions. Using filter paper at 5.0 g/L resulted in the most effective hydrogen production performance, achieving a H2 production rate and yield of 57.7 ml/h/L and 2.03 mol H2/mol hexose, respectively. Production of cellulolytic enzyme activities was positively correlated with the efficiency of dark-H2 fermentation.

  5. Cloning, expression and characterization of glycoside hydrolases from the thermophilic cellulolytic anaerobic bacterium Caldicellulosiruptor kristjanssonii

    OpenAIRE

    Skalman, Lars Nygård

    2010-01-01

    Lignocellulosic biomass has great potential as a substrate for ethanol production as it is a renewable and rather abundant energy source. However, the rigid and complex structure of lignocellulose is a major bottleneck preventing the development of cost-effective production methods. By the use of thermostable cellulolytic enzymes, hydrolysis of cellulose and fermentation of glucose to ethanol could be performed at high temperatures and this would lower the production cost of ethanol significa...

  6. Caldicellulosiruptor obsidiansis sp. nov., an anaerobic, extremely thermophilic, cellulolytic bacterium isolated from Obsidian Pool, Yellowstone National Park

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton-Brehm, Scott [ORNL; Elkins, James G [ORNL; Phelps, Tommy Joe [ORNL; Keller, Martin [ORNL; Carroll, Sue L [ORNL; Allman, Steve L [ORNL; Podar, Mircea [ORNL; Mosher, Jennifer J [ORNL; Vishnivetskaya, Tatiana A [ORNL

    2010-01-01

    A novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated OB47T, was isolated from Obsidian Pool, Yellowstone National Park, WY, USA. The isolate was a non-motile, non-spore forming, Gram-positive rod approximately 2 m long by 0.2 m wide and grew at temperatures between 55-85oC with the optimum at 78oC. The pH range for growth was 6.0-8.0 with values of near 7.0 being optimal. Growth on cellobiose produced the fastest specific growth rates at 0.75 hr-1. The organism also displayed fermentative growth on glucose, maltose, arabinose, fructose, starch, lactose, mannose, sucrose, galactose, xylose, arabinogalactan, Avicel, xylan, filter paper, processed cardboard, pectin, dilute acid-pretreated switchgrass and Populus. OB47T was unable to grow on mannitol, fucose, lignin, Gelrite, acetate, glycerol, ribose, sorbital, carboxymethylcellulose and casein. Yeast extract stimulated growth and thiosulfate, sulfate, nitrate, and sulfur were not reduced. Fermentation end products were mainly acetate, H2, and CO2 although lactate and ethanol were produced in 5 l batch fermentations. The G+C content of the DNA was 35 mol% and sequence analysis of the small subunit ribosomal RNA gene placed OB47T within the genus Caldicellulosiruptor. Based on its phylogenetic and phenotypic properties, the isolate is proposed to be designated Caldicellulosiruptor obsidiansis sp. nov. and OB47T is the type stain (ATCC = ____, JCM = ____).

  7. Kallotenue papyrolyticum gen. nov., sp. nov., a cellulolytic and filamentous thermophile that represents a novel lineage (Kallotenuales ord. nov., Kallotenuaceae fam. nov.) within the class Chloroflexia

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Jesse; Gieler, Brandon; Heisler, Devon; Palisoc, Maryknoll; Williams, Amanda; Dohnalkova, Alice; Ming, Hong; Yu, Tian T.; Dodsworth, Jeremy A.; Li, Wen J.; Hedlund, Brian P.

    2013-08-15

    Several closely-related, thermophilic, and cellulolytic bacterial strains, designated JKG1T, JKG2, JKG3, JKG4, and JKG5, were isolated from a cellulolytic enrichment (corn stover) incubated in the water column of Great Boiling Spring, NV. Strain JKG1T had cells of a diameter of 0.7 - 0.9 μm and length of ~2.0 μm that formed non-branched multicellular filaments reaching >300 μm. Spores were not formed and dense liquid cultures were red. The temperature range for growth was 45-65 °C, with an optimum of 55 °C. The pH range for growth was 5.6-9.0, with an optimum of 7.5. JKG1T grew as an aerobic heterotroph, utilizing glucose, sucrose, xylose, arabinose, cellobiose, carboxymethylcellulose, filter paper, microcrystalline cellulose, xylan, starch, casamino acids, tryptone, peptone, yeast extract, acetate, citrate, lactate, pyruvate, and glycerol as sole carbon sources, and was not observed to photosynthesize. The cells stained Gram-negative. Phylogenetic analysis using 16S rRNA gene sequences placed the new isolates in the class Chloroflexia, but distant from other cultivated members, with the highest sequence identity of 82.5% to Roseiflexus castenholzii. The major quinone was menaquinone-9; no ubiquinones were detected. The major cellular fatty acids (>5%) were C18:0, anteiso-C17:0, iso-C18:0, and iso-C17:0. C16:0, iso-C16:0, and C17:0. The peptidoglycan amino acids were alanine, ornithine, glutamic acid, serine, and asparagine. Whole-cell sugars included mannose, rhamnose, glucose, galactose, ribose, arabinose, and xylose. Morphological, phylogenetic, and chemotaxonomic results suggest that JKG1T is representative of a new lineage within the class Chloroflexia, which we propose to designate Kallotenue papyrolyticum gen. nov., sp. nov., Kallotenuaceae fam. nov., Kallotenuales ord. nov.

  8. Heterologous Expression of Family 10 Xylanases from Acidothermus cellulolyticus Enhances the Exoproteome of Caldicellulosiruptor bescii and Growth on Xylan Substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun-Ki; Chung, Daehwan; Himmel, Michael E.; Bomble, Yannick J.; Westpheling, Janet

    2016-08-22

    The ability to deconstruct plant biomass without conventional pretreatment has made members of the genus Caldicellulosiruptor the target of investigation for the consolidated processing of lignocellulosic biomass to biofuels and bioproducts. These Gram-positive bacteria are hyperthermophilic anaerobes and the most thermophilic cellulolytic organisms so far described. They use both C5 and C6 sugars simultaneously and have the ability to grow well on xylan, a major component of plant cell walls. This is an important advantage for their use to efficiently convert biomass at yields sufficient for an industrial process. For commodity chemicals, yield from substrate is perhaps the most important economic factor. In an attempt to improve even further the ability of C. bescii to use xylan, we introduced two xylanases from Acidothermus cellulolyticus. Acel_0180 includes tandem carbohydrate-binding modules (CBM2 and CBM3) located at the C-terminus, one of which, CBM2, is not present in C. bescii. Also, the sequences of Xyn10A and Acel_0180 have very little homology with the GH10 domains present in C. bescii. For these reasons, we selected these xylanases as potential candidates for synergistic interaction with those in the C. bescii exoproteome. Heterologous expression of two xylanases from Acidothermus cellulolyticus in Caldicellulosiruptor bescii resulted in a modest, but significant increase in the activity of the exoproteome of C. bescii on xylan substrates. Even though the increase in extracellular activity was modest, the ability of C. bescii to grow on these substrates was dramatically improved suggesting that the xylan substrate/microbe interaction substantially increased deconstruction over the secreted free enzymes alone. We anticipate that the ability to efficiently use xylan, a major component of plant cell walls for conversion of plant biomass to products of interest, will allow the conversion of renewable, sustainable, and inexpensive plant feedstocks to

  9. Isolation, Screening and Identification of Thermophilic Cellulolytic Bacteria in Old Stalk of Asparagus Compost%芦笋老茎堆肥中高温纤维素分解菌的分离、筛选及鉴定

    Institute of Scientific and Technical Information of China (English)

    李欣欣; 王琳琳; 申挺挺; 宋志刚; 韩建荣

    2012-01-01

    采用纤维素刚果红培养基在45℃下从芦笋老茎堆肥中分离筛选出52株高温纤维素分解菌.通过水解圈直径与菌落直径比值的比较,进一步获得了6株纤维素分解能力较强的菌株.经菌落形态观察、革兰氏染色、芽孢染色和生理生化试验,6株高温纤维素分解菌初步鉴定为需氧芽孢杆菌(Bacillus spp.).%In this experiment, 52 strains of thermophilic cellulolytic bacteria were isolated and screened from the old stalk of asparagus compost using cellulose - congo red culture medium at 451. By comparing the ratio of hydrolytic circle diameter to colony diameter, 6 strains of cellulolytic bacteria with higher efficient were selected, and they were identified as Bacillus spp. through morphological observation, Gram' s staining, spore staining and physiological - biochemical experiments.

  10. 嗜热厌氧纤维素分解菌的分离、鉴定及其酶学特性%Isolation, identification and enzyme characterization of a thermophilic cellulolytic anaerobic bacterium

    Institute of Scientific and Technical Information of China (English)

    赵银瓶; 马诗淳; 孙颖杰; 黄艳; 邓宇

    2012-01-01

    [目的]分离高效降解纤维素的嗜热厌氧菌,通过与嗜热产乙醇菌株联合培养的方式,为生产纤维素乙醇提供微生物资源.[方法]利用厌氧分离技术从降解纤维素的马粪富集物中分离到一株嗜热厌氧细菌HCp.采用形态学观察、生理生化鉴定、结合16S rDNA序列的系统发育学分析确定该菌株的分类地位,利用DNS酶活分析方法测定此分离菌株的酶学性质.[结果]分离菌株HCp革兰氏染色阴性,直杆,细胞单个或成对出现,菌体大小为(0.35 -0.50) μm×(2.42 -6.40) μm,严格厌氧,形成芽胞,能运动,对新霉素有一定的抗性.此菌能利用滤纸纤维素、纤维素粉、微晶纤维素、脱脂棉和水稻秸秆、明胶等,还可以利用葡萄糖、纤维二糖、木糖、木聚糖、果糖、蔗糖、核糖、半乳糖、麦芽糖、山梨糖、海藻糖、蜜二糖、甘露糖等.该菌株在pH6.5 -8.5、温度35 - 70℃、盐浓度0% - 1.0%范围内利用纤维素生长,最适pH为6.85,最适温度为60℃,最适NaCl浓度为0.2%,最佳生长条件下,在10 d内滤纸纤维素降解率可达90.40%.在HCp的纤维小体中,滤纸酶、羧甲基纤维素酶、β-葡萄糖苷酶、木聚糖酶的最适作用温度分别为70℃、70℃、70℃、60℃,并且羧甲基纤维素酶具有较高的热稳定性.部分长度的16S rDNA序列分析表明,分离菌株HCp与Acetivibrio cellulolyticus、A.cellulosolvens相似性为97.5%.[结论]分离菌株HCp是从马粪富集物中分离到的一株嗜热厌氧细菌,该菌具有较强的降解纤维素能力,生长温度范围广,酶的热稳定性好,纤维素底物利用广泛等特性,为纤维素降解产乙醇提供了良好的材料.%[Objective ] To identify a thermophilic bacterium from horse manure to degrade cellulose efficiently, and to enrich microbial resources producing cellulolytic ethanol by co-culturing with thermophilic ethanol producing bacterium. [Methods] We used Hungate anaerobic

  11. Thermophilic, lignocellulolytic bacteria for ethanol production: current state and perspectives

    DEFF Research Database (Denmark)

    Chang, Tinghong; Yao, Shuo

    2011-01-01

    for efficient biomass hydrolysis. Secondly, thermophilic bacteria ferment a broad range of carbohydrates into ethanol, and some of them display potential for ethanologenic fermentation at high yield. Thirdly, the establishment of the genetic tools for thermophilic bacteria has allowed metabolic engineering...... of cellulolytic and saccharolytic thermophilic bacteria for lignocellulosic ethanol production because of their unique properties. First of all, thermophilic bacteria possess unique cellulolytic and hemicellulolytic systems and are considered as potential sources of highly active and thermostable enzymes......, in particular with emphasis on improving ethanol yield, and this facilitates their employment for ethanol production. Finally, different processes for second-generation ethanol production based on thermophilic bacteria have been proposed with the aim to achieve cost-competitive processes. However, thermophilic...

  12. Biodiversity characterization of cellulolytic bacteria present on native Chaco soil by comparison of ribosomal RNA genes.

    Science.gov (United States)

    Talia, Paola; Sede, Silvana M; Campos, Eleonora; Rorig, Marcela; Principi, Dario; Tosto, Daniela; Hopp, H Esteban; Grasso, Daniel; Cataldi, Angel

    2012-04-01

    Sequence analysis of the 16S ribosomal RNA gene was used to study bacterial diversity of a pristine forest soil and of two cultures of the same soil enriched with cellulolytic bacteria. Our analysis revealed high bacterial diversity in the native soil sample, evidencing at least 10 phyla, in which Actinobacteria, Proteobacteria and Acidobacteria accounted for more than 76% of all sequences. In both enriched samples, members of Proteobacteria were the most frequently represented. The majority of bacterial genera in both enriched samples were identified as Brevundimonas and Caulobacter, but members of Devosia, Sphingomonas, Variovorax, Acidovorax, Pseudomonas, Xanthomonas, Stenotrophomonas, Achromobacter and Delftia were also found. In addition, it was possible to identify cellulolytic taxa such as Acidothermus, Micromonospora, Streptomyces, Paenibacillus and Pseudomonas, which indicates that this ecosystem could be an attractive source for study of novel enzymes for cellulose degradation. PMID:22202170

  13. Expression and Characterization of Acidothermus celluloyticus E1 Endoglucanase in Transgenic Duckweed Lemna minor 8627

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y.; Cheng, J. J.; Himmel, M. E.; Skory, C. D.; Adney, W. S.; Thomas, S. R.; Tisserat, B.; Nishimura, Y.; Yamamoto, Y. T.

    2007-01-01

    Endoglucanase E1 from Acidothermus cellulolyticus was expressed cytosolically under control of the cauliflower mosaic virus 35S promoter in transgenic duckweed, Lemna minor 8627 without any obvious observable phenotypic effects on morphology or rate of growth. The recombinant enzyme co-migrated with the purified catalytic domain fraction of the native E1 protein on western blot analysis, revealing that the cellulose-binding domain was cleaved near or in the linker region. The duckweed-expressed enzyme was biologically active and the expression level was up to 0.24% of total soluble protein. The endoglucanase activity with carboxymethylcellulose averaged 0.2 units mg protein{sup -1} extracted from fresh duckweed. The optimal temperature and pH for E1 enzyme activity were about 80 C and pH 5, respectively. While extraction with HEPES (N-[2-hydroxyethyl]piperazine-N{prime}-[2-ethanesulfonic acid]) buffer (pH 8) resulted in the highest recovery of total soluble proteins and E1 enzyme, extraction with citrate buffer (pH 4.8) at 65 C enriched relative amounts of E1 enzyme in the extract. This study demonstrates that duckweed may offer new options for the expression of cellulolytic enzymes in transgenic plants.

  14. Ferrofluid and cellulolytic fungi

    Science.gov (United States)

    Manoliu, Al.; Oprica, Lacramioara; Creanga, Dorina-Emilia

    2005-03-01

    The study of petroleum ferrofluid influence upon the biology of the cellulolytic fungus Chaetomium globosum, with implications in cellulose biotechnology, was carried out. Taking into account previous results revealing the ferrofluid effects on the cellulose enzyme complex as well as on the dehydrogenases, the results of the investigation of catalase and peroxidase behavior are presented in this paper. The intensification of catalase biosynthesis in response to the increase of hydrogen peroxide after fungus cell interference with the petroleum ferrofluid was the main issue of the experiments.

  15. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives

    NARCIS (Netherlands)

    Bielen, A.A.M.; Verhaart, M.R.A.; Oost, van der J.; Kengen, S.W.M.

    2013-01-01

    Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit fo

  16. Anaerobic thermophiles.

    Science.gov (United States)

    Canganella, Francesco; Wiegel, Juergen

    2014-01-01

    The term "extremophile" was introduced to describe any organism capable of living and growing under extreme conditions. With the further development of studies on microbial ecology and taxonomy, a variety of "extreme" environments have been found and an increasing number of extremophiles are being described. Extremophiles have also been investigated as far as regarding the search for life on other planets and even evaluating the hypothesis that life on Earth originally came from space. The first extreme environments to be largely investigated were those characterized by elevated temperatures. The naturally "hot environments" on Earth range from solar heated surface soils and water with temperatures up to 65 °C, subterranean sites such as oil reserves and terrestrial geothermal with temperatures ranging from slightly above ambient to above 100 °C, to submarine hydrothermal systems with temperatures exceeding 300 °C. There are also human-made environments with elevated temperatures such as compost piles, slag heaps, industrial processes and water heaters. Thermophilic anaerobic microorganisms have been known for a long time, but scientists have often resisted the belief that some organisms do not only survive at high temperatures, but actually thrive under those hot conditions. They are perhaps one of the most interesting varieties of extremophilic organisms. These microorganisms can thrive at temperatures over 50 °C and, based on their optimal temperature, anaerobic thermophiles can be subdivided into three main groups: thermophiles with an optimal temperature between 50 °C and 64 °C and a maximum at 70 °C, extreme thermophiles with an optimal temperature between 65 °C and 80 °C, and finally hyperthermophiles with an optimal temperature above 80 °C and a maximum above 90 °C. The finding of novel extremely thermophilic and hyperthermophilic anaerobic bacteria in recent years, and the fact that a large fraction of them belong to the Archaea has definitely

  17. Anaerobic Thermophiles

    Directory of Open Access Journals (Sweden)

    Francesco Canganella

    2014-02-01

    Full Text Available The term “extremophile” was introduced to describe any organism capable of living and growing under extreme conditions. With the further development of studies on microbial ecology and taxonomy, a variety of “extreme” environments have been found and an increasing number of extremophiles are being described. Extremophiles have also been investigated as far as regarding the search for life on other planets and even evaluating the hypothesis that life on Earth originally came from space. The first extreme environments to be largely investigated were those characterized by elevated temperatures. The naturally “hot environments” on Earth range from solar heated surface soils and water with temperatures up to 65 °C, subterranean sites such as oil reserves and terrestrial geothermal with temperatures ranging from slightly above ambient to above 100 °C, to submarine hydrothermal systems with temperatures exceeding 300 °C. There are also human-made environments with elevated temperatures such as compost piles, slag heaps, industrial processes and water heaters. Thermophilic anaerobic microorganisms have been known for a long time, but scientists have often resisted the belief that some organisms do not only survive at high temperatures, but actually thrive under those hot conditions. They are perhaps one of the most interesting varieties of extremophilic organisms. These microorganisms can thrive at temperatures over 50 °C and, based on their optimal temperature, anaerobic thermophiles can be subdivided into three main groups: thermophiles with an optimal temperature between 50 °C and 64 °C and a maximum at 70 °C, extreme thermophiles with an optimal temperature between 65 °C and 80 °C, and finally hyperthermophiles with an optimal temperature above 80 °C and a maximum above 90 °C. The finding of novel extremely thermophilic and hyperthermophilic anaerobic bacteria in recent years, and the fact that a large fraction of them belong

  18. DECENTRALIZED THERMOPHILIC BIOHYDROGEN: A MORE EFFICIENT AND COST EFFECTIVE PROCESS

    Directory of Open Access Journals (Sweden)

    Rajesh K. Sani

    2011-11-01

    Full Text Available Nonfood lignocellulosic biomass is an ideal substrate for biohydrogen production. By avoiding pretreatment steps (acid, alkali, or enzymatic, there is potential to make the process economical. Utilization of regional untreated lignocellulosic biomass by cellulolytic and fermentative thermophiles in a consolidated mode using a single reactor is one of the ways to achieve economical and sustainable biohydrogen production. Employing these potential microorganisms along with decentralized biohydrogen energy production will lead us towards regional and national independence having a positive influence on the bioenergy sector.

  19. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives

    OpenAIRE

    Kengen, Servé W. M.; Verhaart, Marcel R. A.; John van der Oost; Abraham A. M. Bielen

    2013-01-01

    Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit for dark fermentation of 4 mol hydrogen per mol hexose, this organism has proven itself to be an excellent candidate for biological hydrogen production. This review provides an overview of the resear...

  20. EXTRACELLULAR CELLULOLYTIC COMPLEXES PRODUCTION BY MICROSCOPIC FUNGI

    Directory of Open Access Journals (Sweden)

    S. O. Syrchin

    2015-10-01

    Full Text Available The aim of this work was to screen and to study the effect of inducers on the synthesis of the cellulolytic enzyme complexes by microscopic fungi. Cellulolytic and xylanolytic activities were determined by reducing sugar with DNS reagent, and β-glucosidase activity by pNPG hydrolysis. The enzyme preparations were obtained by ammonium sulphate precipitation. Among 32 studied strains of microscopic fungi 14 produced cellulo- and xylanolytic enzyme complexes. Fusarium sp. 5 and Fennellia sp. 2806 demonstrated the highest levels of all studied enzyme activities. Enzyme preparations with high endo-, exoglucanase, xylanase and β-glucosidase activities were obtained from these strains. Fusarium sp. 5 and Fennellia sp. 2806 were active producers of cellulase enzyme complexes during growth on natural substrates. It was shown that inductors of cellulolytic enzymes in Fusarium sp. 5 and Fennellia sp. 2806 differed from the ones in Trichoderma reesei.

  1. Properties of thermophilic microorganisms

    International Nuclear Information System (INIS)

    Microorganisms are called thermophilic or extreme thermophilic (caldo-active) if they grow and reproduce over 470C and 700C, respectively. A survey of growth characteristics of thermophiles is presented and it includes those which also live at extreme pH. The prevalent but not completely emcompassing theory of the ability of thermophiles to grow at high temperatures is that they have macromolecules and cell organelles with high thermostability. Work on some proteins and cell organelles from thermophiles is reviewed. The thermostabilities of these components are compared with those of the living cells, and factors which may govern optimum as well as minimum growth temperatures of microorganisms are discussed. Examples are from the literature but also include enzymes involved in tetrahydrofolate metabolism and other proteins of acetogenic therhmophilic bacteria which are presently studied in the author's laboratory

  2. High level expression of Acidothermus cellulolyticus β-1, 4-endoglucanase in transgenic rice enhances the hydrolysis of its straw by cultured cow gastric fluid

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Hong L.; Dai, Ziyu; Hsieh, Chia W.; Ku, Maurice S.

    2011-12-10

    Large-scale production of effective cellulose hydrolytic enzymes is the key to the bioconversion of agricultural residues to ethanol. The goal of this study was to develop a rice plant as a bioreactor for the large-scale production of cellulose hydrolytic enzymes via genetic transformation, and to simultaneously improve rice straw as an efficient biomass feedstock for conversion of cellulose to glucose. In this study, the cellulose hydrolytic enzyme {beta}-1, 4-endoglucanase (E1) from the thermophilic bacterium Acidothermus cellulolyticus was overexpressed in rice through Agrobacterium-mediated transformation. The expression of the bacterial gene in rice was driven by the constitutive Mac promoter, a hybrid promoter of Ti plasmid mannopine synthetase promoter and cauliflower mosaic virus 35S promoter enhancer with the signal peptide of tobacco pathogenesis-related protein for targeting the protein to the apoplastic compartment for storage. A total of 52 transgenic rice plants from six independent lines expressing the bacterial enzyme were obtained, which expressed the gene at high levels with a normal phenotype. The specific activities of E1 in the leaves of the highest expressing transgenic rice lines were about 20 fold higher than those of various transgenic plants obtained in previous studies and the protein amounts accounted for up to 6.1% of the total leaf soluble protein. Zymogram and temperature-dependent activity analyses demonstrated the thermostability of the enzyme and its substrate specificity against cellulose, and a simple heat treatment can be used to purify the protein. In addition, hydrolysis of transgenic rice straw with cultured cow gastric fluid yielded almost twice more reducing sugars than wild type straw. Taken together, these data suggest that transgenic rice can effectively serve as a bioreactor for large-scale production of active, thermostable cellulose hydrolytic enzymes. As a feedstock, direct expression of large amount of cellulases in

  3. Pyrosequencing reveals high-temperature cellulolytic microbial consortia in Great Boiling Spring after in situ lignocellulose enrichment.

    Directory of Open Access Journals (Sweden)

    Joseph P Peacock

    Full Text Available To characterize high-temperature cellulolytic microbial communities, two lignocellulosic substrates, ammonia fiber-explosion-treated corn stover and aspen shavings, were incubated at average temperatures of 77 and 85°C in the sediment and water column of Great Boiling Spring, Nevada. Comparison of 109,941 quality-filtered 16S rRNA gene pyrosequences (pyrotags from eight enrichments to 37,057 quality-filtered pyrotags from corresponding natural samples revealed distinct enriched communities dominated by phylotypes related to cellulolytic and hemicellulolytic Thermotoga and Dictyoglomus, cellulolytic and sugar-fermenting Desulfurococcales, and sugar-fermenting and hydrogenotrophic Archaeoglobales. Minor enriched populations included close relatives of hydrogenotrophic Thermodesulfobacteria, the candidate bacterial phylum OP9, and candidate archaeal groups C2 and DHVE3. Enrichment temperature was the major factor influencing community composition, with a negative correlation between temperature and richness, followed by lignocellulosic substrate composition. This study establishes the importance of these groups in the natural degradation of lignocellulose at high temperatures and suggests that a substantial portion of the diversity of thermophiles contributing to consortial cellulolysis may be contained within lineages that have representatives in pure culture.

  4. Thermophilic Biohydrogen Production

    DEFF Research Database (Denmark)

    Karakashev, Dimitar Borisov; Angelidaki, Irini

    2011-01-01

    Dark fermentative hydrogen production at thermophilic conditions is attractive process for biofuel production. From thermodynamic point of view, higher temperatures favor biohydrogen production. Highest hydrogen yields are always associated with acetate, or with mixed acetate- butyrate type...... fermentation. On the contrary the hydrogen yield decreases, with increasing concentrations of lactate, ethanol or propionate. Major factors affecting dark fermentative biohydrogen production are organic loading rate (OLR), pH, hydraulic retention time (HRT), dissolved hydrogen and dissolved carbon dioxide...... concentrations, and soluble metabolic profile (SMP). A number of thermophilic and extreme thermophilic cultures (pure and mixed) have been studied for biohydrogen production from different feedstocks - pure substrates and waste/wastewaters. Variety of process technologies (operational conditions...

  5. Screening genus Penicillium for producers of cellulolytic and xylanolytic enzymes

    DEFF Research Database (Denmark)

    Krogh, Kristian Bertel Rømer; Mørkeberg, Astrid; Frisvad, Jens Christian;

    2004-01-01

    For enzymatic hydrolysis of lignocellulosic material, cellulolytic enzymes from Trichoderma reesei are most commenly used, but, there is a need for more efficient enzyme cocktails. In this study, the production of cellulolytic and xylanolytic enzymes was investigated in 12 filamentous fungi from...

  6. Thermophilic microorganisms in biomining.

    Science.gov (United States)

    Donati, Edgardo Rubén; Castro, Camila; Urbieta, María Sofía

    2016-11-01

    Biomining is an applied biotechnology for mineral processing and metal extraction from ores and concentrates. This alternative technology for recovering metals involves the hydrometallurgical processes known as bioleaching and biooxidation where the metal is directly solubilized or released from the matrix for further solubilization, respectively. Several commercial applications of biomining can be found around the world to recover mainly copper and gold but also other metals; most of them are operating at temperatures below 40-50 °C using mesophilic and moderate thermophilic microorganisms. Although biomining offers an economically viable and cleaner option, its share of the world´s production of metals has not grown as much as it was expected, mainly considering that due to environmental restrictions in many countries smelting and roasting technologies are being eliminated. The slow rate of biomining processes is for sure the main reason of their poor implementation. In this scenario the use of thermophiles could be advantageous because higher operational temperature would increase the rate of the process and in addition it would eliminate the energy input for cooling the system (bioleaching reactions are exothermic causing a serious temperature increase in bioreactors and inside heaps that adversely affects most of the mesophilic microorganisms) and it would decrease the passivation of mineral surfaces. In the last few years many thermophilic bacteria and archaea have been isolated, characterized, and even used for extracting metals. This paper reviews the current status of biomining using thermophiles, describes the main characteristics of thermophilic biominers and discusses the future for this biotechnology. PMID:27628339

  7. Evaluation of cellulolytic activity in insect digestive fluids.

    Science.gov (United States)

    Su, L-J; Zhang, H-F; Yin, X-M; Chen, M; Wang, F-Q; Xie, H; Zhang, G-Z; Song, A-D

    2013-01-01

    Efficient and low-cost cellulolytic enzymes are urgently needed to degrade recalcitrant plant biomass during the industrial production of lignocellulosic biofuels. Here, the cellulolytic activities in the gut fluids of 54 insect species that belong to 7 different taxonomic orders were determined using 2 different substrates, carboxymethyl cellulose (CMC) (approximating endo-β-1,4-glucanase) and filter paper (FP) (total cellulolytic activities). The use of CMC as the substrate in the zymogram analysis resulted in the detection of distinct cellulolytic protein bands. The cellulolytic activities in the digestive system of all the collected samples were detected using cellulolytic activity analysis. The highest CMC gut fluid activities were found in Coleoptera and Orthoptera, while FP analysis indicated that higher gut fluid activities were found in several species of Coleoptera and Lepidoptera. In most cases, gut fluid activities were higher with CMC than with FP substrate, except for individual Lepidoptera species. Our data indicate that the origin of cellulolytic enzymes probably reflects the phylogenetic relationship and feeding strategies of different insects. PMID:23315870

  8. An Efficient and Improved Methodology for the Screening of Industrially Valuable Xylano-Pectino-Cellulolytic Microbes

    OpenAIRE

    Avtar Singh; Amanjot Kaur; Anita Dua; Ritu Mahajan

    2015-01-01

    Xylano-pectino-cellulolytic enzymes are valuable enzymes of the industrial sector. In our earlier study, we have reported a novel and cost effective methodology for the qualitative screening of cellulase-free xylano-pectinolytic microorganisms by replacing the commercial, highly expensive substrates with agricultural residues, but the microorganisms with xylanolytic, pectinolytic, cellulolytic, xylano-pectinolytic, xylano-cellulolytic, pectino-cellulolytic, and xylano-pectino-cellulolytic pot...

  9. The Activity of Cellulase from Thermophilic Fungi Isolated from CaneBagasses

    International Nuclear Information System (INIS)

    The activity of cellulase from thermophilic fungi isolated from canebagasses has been measured. This wild strain, named fungal strain PJ-2,secreted a large amount of cellulolytic enzyme components consisting of 0.46units of avicelase, 0.8 units of carboxymethyl cellulose hydrolizing enzyme(CMCase) and 0.5 units of β-glucosidase per ml of culture broth oncultivation in Mandels Reese medium for 7 days at 500 oC. These cellulasesproduction was lower than that of Trichoderma reesei NRRL 3653 producing 0.5units/ml avicelase, 1.6 units/ml CMCase and 0.4 units/ml ofβ-glucosidase cultivated in the same medium at 30 oC. However,thermophilic fungi may be potential to be exploited in lignocellulosedegradation at the tropical areas as the process usually needs temperature ofabove 50 oC. (author)

  10. High level expression of Acidothermus cellulolyticus β-1, 4-endoglucanase in transgenic rice enhances the hydrolysis of its straw by cultured cow gastric fluid

    Directory of Open Access Journals (Sweden)

    Chou Hong

    2011-12-01

    Full Text Available Abstract Background Large-scale production of effective cellulose hydrolytic enzymes is the key to the bioconversion of agricultural residues to ethanol. The goal of this study was to develop a rice plant as a bioreactor for the large-scale production of cellulose hydrolytic enzymes via genetic transformation, and to simultaneously improve rice straw as an efficient biomass feedstock for conversion of cellulose to glucose. Results In this study, the cellulose hydrolytic enzyme β-1, 4-endoglucanase (E1 gene, from the thermophilic bacterium Acidothermus cellulolyticus, was overexpressed in rice through Agrobacterium-mediated transformation. The expression of the bacterial E1 gene in rice was driven by the constitutive Mac promoter, a hybrid promoter of Ti plasmid mannopine synthetase promoter and cauliflower mosaic virus 35S promoter enhancer, with the signal peptide of tobacco pathogenesis-related protein for targeting the E1 protein to the apoplastic compartment for storage. A total of 52 transgenic rice plants from six independent lines expressing the bacterial E1 enzyme were obtained that expressed the gene at high levels without severely impairing plant growth and development. However, some transgenic plants exhibited a shorter stature and flowered earlier than the wild type plants. The E1 specific activities in the leaves of the highest expressing transgenic rice lines were about 20-fold higher than those of various transgenic plants obtained in previous studies and the protein amounts accounted for up to 6.1% of the total leaf soluble protein. A zymogram and temperature-dependent activity analyses demonstrated the thermostability of the E1 enzyme and its substrate specificity against cellulose, and a simple heat treatment can be used to purify the protein. In addition, hydrolysis of transgenic rice straw with cultured cow gastric fluid for one hour at 39°C and another hour at 81°C yielded 43% more reducing sugars than wild type rice

  11. Production of cellulolytic enzymes from ascomycetes

    DEFF Research Database (Denmark)

    Hansen, Gustav Hammerich; Lübeck, Mette; Frisvad, Jens Christian;

    2015-01-01

    Optimizing production of cellulose degrading enzymes is of great interest in order to increase the feasibility of constructing biorefinery facilities for a sustainable supply of energy and chemical products. The ascomycete phylum has a large potential for the production of cellulolytic enzymes....... Although numerous enzymatic profiles have already been unraveled, the research has been covering only a limited number of species and genera, thus leaving many ascomycetes to be analyzed. Such analysis requires choosing appropriate media and cultivation methods that ensure enzyme profiles with high...... specificities and activities. However, the choice of media, cultivation methods and enzyme assays highly affect the enzyme activity profile observed. This review provides an overview of enzymatic profiles for several ascomycetes covering phylogenetically distinct genera and species. The profiles of cellulose...

  12. Hydrolytic bacteria in mesophilic and thermophilic degradation of plant biomass

    Energy Technology Data Exchange (ETDEWEB)

    Zverlov, Vladimir V.; Hiegl, Wolfgang; Koeck, Daniela E.; Koellmeier, Tanja; Schwarz, Wolfgang H. [Department of Microbiology, Technische Universitaet Muenchen, Freising-Weihenstephan (Germany); Kellermann, Josef [Max Planck Institute for Biochemistry, Am Klopferspitz, Martinsried (Germany)

    2010-12-15

    Adding plant biomass to a biogas reactor, hydrolysis is the first reaction step in the chain of biological events towards methane production. Maize silage was used to enrich efficient hydrolytic bacterial consortia from natural environments under conditions imitating those in a biogas plant. At 55-60 C a more efficient hydrolyzing culture could be isolated than at 37 C. The composition of the optimal thermophilic bacterial consortium was revealed by sequencing clones from a 16S rRNA gene library. A modified PCR-RFLP pre-screening method was used to group the clones. Pure anaerobic cultures were isolated. 70% of the isolates were related to Clostridium thermocellum. A new culture-independent method for identification of cellulolytic enzymes was developed using the isolation of cellulose-binding proteins. MALDI-TOF/TOF analysis and end-sequencing of peptides from prominent protein bands revealed cellulases from the cellulosome of C. thermocellum and from a major cellulase of Clostridium stercorarium. A combined culture of C. thermocellum and C. stercorarium was shown to excellently degrade maize silage. A spore preparation method suitable for inoculation of maize silage and optimal hydrolysis was developed for the thermophilic bacterial consortium. This method allows for concentration and long-term storage of the mixed culture for instance for inoculation of biogas fermenters. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Isolation and characterization of Caldicellulosiruptor lactoaceticus sp. nov., an extremely thermophilic, cellulolytic, anaerobic bacterium

    DEFF Research Database (Denmark)

    Mladenovska, Zuzana; Mathrani, Indra M.; Ahring, Birgitte Kiær

    1995-01-01

    and ethanol occurred as minor fermentation products. Only a restricted number of carbon sources (cellulose, xylan, starch, pectin, cellobiose, xylose, maltose and lactose) were used as substrates. During growth on Avicel, the bacterium produced free cellulases with carboxymethylcellulase and avicelase...

  14. Identification and molecular modeling of a family 5 endocellulase from Thermus caldophilus GK24, a cellulolytic strain of Thermus thermophilus

    Directory of Open Access Journals (Sweden)

    Dae-Sil Lee

    2006-12-01

    Full Text Available The genome of T. caldophilus GK24 was recently sequenced and annotated as 14contigs, equivalent to 2.3 mega basepairs (Mbp of DNA. In the current study, we identifieda unique 13.7 kbp DNA sequence, which included the endocellulase gene of T. caldophilusGK24, which did not appear to be present in the complete genomic sequence of the closelyrelated species T. thermophilus HB27 and HB8. Congo-red staining revealed a uniquephenotype of cellulose degradation by strain GK24 that was distinct from other closelyrelated Thermus strains. The results showed that strain GK24 is an aerobic, thermophilic,cellulolytic eubacterium which belongs to the group T. thermophilus. In order to understandthe mechanism of production of cellobiose in T. caldophilus GK24, a three-dimensionalmodel of the endocellulase, TcCel5A, was generated based on known crystal structures.Using this model, we carried out a flexible cellotetraose docking study.

  15. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu; Tang, Lan; Henriksen, Svend Hostgaard Bang

    2016-05-17

    The present invention provides isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also provides nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  16. Hydrogen Production by Thermophilic Fermentation

    NARCIS (Netherlands)

    Niel, van E.W.J.; Willquist, K.; Zeidan, A.A.; Vrije, de T.; Mars, A.E.; Claassen, P.A.M.

    2012-01-01

    Of the many ways hydrogen can be produced, this chapter focuses on biological hydrogen production by thermophilic bacteria and archaea in dark fermentations. The thermophiles are held as promising candidates for a cost-effective fermentation process, because of their relatively high yields and broad

  17. Cellulolytic Enzymes Production by Solid State Culture

    Directory of Open Access Journals (Sweden)

    Miguel A. Medina-Morales

    2011-01-01

    Full Text Available Problem statement: Great interest in the use of lignocellulosic biomass is increasing in order to diminish the accumulation of residues, such as pecan nut shells. One of the alternatives is the fungal degradation of these residues. Approach: The capacity of Trichoderma (coded as T1, T2 and T3 strains to produce cellulase and xylonite was evaluated. Results: Pecan nut shell fibers were used as sole carbon source. The fiber characterization study showed that cellulose levels were of 0.1% while hemicellulose was up to 25 %. Three Trichoderma strains were used on solid fungal cultures using the fibers as sole carbon and inductor source for the production of cellulolytic enzymes. The behavior of the sugars liberated by the fungi showed that the strain T2 is able to accumulate more monomeric reducing sugars than the other two strains, this could be attributed at this strain has a higher sugar liberation rate and slower sugar consumption rate. This strain also expressed more cellulase and xylanase activity. The low quantity of cellulose registered in the fibers can still be used to induce cellulase activity. Conclusion: The T2 strain had the highest level of enzymatic activity both cellulase and xylanase.

  18. Thermophilic degradation of cellulosic biomass

    Science.gov (United States)

    Ng, T.; Zeikus, J. G.

    1982-12-01

    The conversion of cellulosic biomass to chemical feedstocks and fuel by microbial fermentation is an important objective of developing biotechnology. Direct fermentation of cellulosic derivatives to ethanol by thermophilic bacteria offers a promising approach to this goal. Fermentations at elevated temperatures lowers the energy demand for cooling and also facilitates the recovery of volatile products. In addition, thermophilic microorganisms possess enzymes with greater stability than those from mesophilic microorganisms. Three anaerobic thermophilic cocultures that ferment cellulosic substrate mainly to ethanol have been described: Clostridium thermocellum/Clostriidium thermohydrosulfuricum, C. thermocellum/Clostridium thermosaccharolyticum, and C. thermocellum/Thermoanaerobacter ethanolicus sp. nov. The growth characteristics and metabolic features of these cocultures are reviewed.

  19. Thermophilic molds: Biology and applications.

    Science.gov (United States)

    Singh, Bijender; Poças-Fonseca, Marcio J; Johri, B N; Satyanarayana, Tulasi

    2016-11-01

    Thermophilic molds thrive in a variety of natural habitats including soils, composts, wood chip piles, nesting materials of birds and other animals, municipal refuse and others, and ubiquitous in their distribution. These molds grow in simple media containing carbon and nitrogen sources and mineral salts. Polyamines are synthesized in these molds and the composition of lipids varies considerably, predominantly containing palmitic, oleic and linoleic acids with low levels of lauric, palmiotoleic and stearic acids. Thermophilic molds are capable of efficiently degrading organic materials by secreting thermostable enzymes, which are useful in the bioremediation of industrial wastes and effluents that are rich in oil, heavy metals, anti-nutritional factors such as phytic acid and polysaccharides. Thermophilic molds synthesize several antimicrobial substances and biotechnologically useful miscellaneous enzymes. The analysis of genomes of thermophilic molds reveals high G:C contents, shorter introns and intergenic regions with lesser repetitive sequences, and further confirms their ability to degrade agro-residues efficiently. Genetic engineering has aided in ameliorating the characteristics of the enzymes of thermophilic molds. This review is aimed at focusing on the biology of thermophilic molds with emphasis on recent developments in the analysis of genomes, genetic engineering and potential applications. PMID:26777293

  20. Thermophilic bacteria in Moroccan hot springs, salt marshes and desert soils

    Directory of Open Access Journals (Sweden)

    Tarik Aanniz

    2015-06-01

    Full Text Available The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240 thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5% represented by B. licheniformis (119, B. aerius (44, B. sonorensis (33, B. subtilis (subsp. spizizenii (2 and subsp. inaquosurum (6, B. amyloliquefaciens (subsp. amyloliquefaciens (4 and subsp. plantarum (4, B. tequilensis (3, B. pumilus (3 and Bacillus sp. (19. Only six isolates (2.5% belonged to the genus Aeribacillus represented by A. pallidus (4 and Aeribacillus sp. (2. In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.

  1. Thermophilic bacteria in Moroccan hot springs, salt marshes and desert soils.

    Science.gov (United States)

    Aanniz, Tarik; Ouadghiri, Mouna; Melloul, Marouane; Swings, Jean; Elfahime, Elmostafa; Ibijbijen, Jamal; Ismaili, Mohamed; Amar, Mohamed

    2015-06-01

    The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240) thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5%) represented by B. licheniformis (119), B. aerius (44), B. sonorensis (33), B. subtilis (subsp. spizizenii (2) and subsp. inaquosurum (6)), B. amyloliquefaciens (subsp. amyloliquefaciens (4) and subsp. plantarum (4)), B. tequilensis (3), B. pumilus (3) and Bacillus sp. (19). Only six isolates (2.5%) belonged to the genus Aeribacillus represented by A. pallidus (4) and Aeribacillus sp. (2). In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.

  2. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu; Duan, Junxin; Tang, Lan; Wu, Wenping

    2016-06-14

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  3. Cellulolytic and xylanolytic activities of common indoor fungi

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Poulsen, Rehab; Hansen, Gustav Hammerich

    2016-01-01

    or no cellulolytic and xylanolytic activities using AZCL-assays. On the other hand, both Cladosporium sphaerospermum and Penicillium chrysogenum showed the highest cellulase, β-glucosidase, mannase, β-galactanase and arabinanase activities and would be good candidates for over-producers of enzymes needed...

  4. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

    Science.gov (United States)

    Schnorr, Kirk; Kramer, Randall

    2016-04-05

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  5. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Schnorr, Kirk; Kramer, Randall

    2016-08-09

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  6. Polypeptides having cellulolytic enhancing activity and nucleic acids encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kimberly; Harris, Paul; Zaretsky, Elizabeth; Re, Edward; Vlasenko, Elena; McFarland, Keith; Lopez de Leon, Alfredo

    2016-08-09

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

  7. Polypeptides having cellulolytic enhancing activity and nucleic acids encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kimberly; Harris, Paul; Zaretsky, Elizabeth; Re, Edward; Vlasenko, Elena; McFarland, Keith; Lopez de Leon, Alfredo

    2014-09-30

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

  8. Methanogenesis in Thermophilic Biogas Reactors

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær

    1995-01-01

    against Methanothrix soehngenii or Methanothrix CALS-I in any of the thermophilic biogas reactors examined. Studies using 2-14C-labeled acetate showed that at high concentrations (more than approx. 1 mM) acetate was metabolized via the aceticlastic pathway, transforming the methyl-group of acetate...... microorganism into methane. In thermophilic biogas reactors,, acetate oxidizing cultures occupied the niche of Methanothrix species, aceticlastic methanogens which dominate at low acetate concentrations in mesophilic systems. Normally, thermophilic biogas reactors are operated at temperatures from 52 to 560 C....... Experiments using biogas reactors fed with cow manure showed that the same biogas yield found at 550 C could be obtained at 610 C after a long adaptation period. However, propionate degradation was inhibited by increasing the temperature....

  9. A novel thermophilic endoglucanase from a mesophilic fungus Fusarium oxysporum

    Institute of Scientific and Technical Information of China (English)

    LIU Shuyan; DUAN Xinyuan; LU Xuemei; GAO Peiji

    2006-01-01

    A novel thermophilic endoglucanase (EGt) was extracted from a mesophilic fungus (Fusarium oxysporum L19). We invoked conventional kinetic enzyme reactions using the sodium salt of carboxymethyl cellulose (CMC-Na) as substrate. EGt displayed optimal activity at 75℃ when kept running 30 min in the temperature range of 30―85℃. Thermal stability curve measured at 70℃ suggested that its half-life time is 15.1 min. The activity was enhanced in the presence of Co2+ or Mg2+ but inhibited by Pb2+ and Fe3+. Moreover, N-bromosuccinimide (NBS) modification resulted in a complete loss of EGt activity, suggesting that tryptophan residues 5 be involved in the enzyme active site. Amino acid composition analysis demonstrated that EGt contains more proline residues. EGt lacks activity towards p-nitrophenyl cellobiose (pNPC). The N-terminal amino acid sequence of EGt is SYRVPAANGFPNP- DASQEKQ, and the gene of EGt was sequenced and analyzed. Extensive sequence alignments failed to show any homology between EGt and any known endoglucanases. This is the first report addressing the thermal adaptation of a cellulolytic enzyme from the mesophilic fungus F. oxysporum. 5be the expression of multiple isoenzyme in an organism helps it adapt to complex living environments.

  10. Malbranchea cinnamomea: A thermophilic fungal source of catalytically efficient lignocellulolytic glycosyl hydrolases and metal dependent enzymes.

    Science.gov (United States)

    Mahajan, Chhavi; Basotra, Neha; Singh, Surender; Di Falco, Marcos; Tsang, Adrian; Chadha, B S

    2016-01-01

    This study reports thermophilic fungus Malbranchea cinnamomea as an important source of lignocellulolytic enzymes. The secretome analysis using LC-MS/MS orbitrap showed that fungus produced a spectrum of glycosyl hydrolases (cellulase/hemicellulase), polysaccharide lyases (PL) and carbohydrate esterases (CE) in addition to cellobiose dehydrogenase (CDH) indicating the presence of functional classical and oxidative cellulolytic mechanisms. The protein fractions in the secretome resolved by ion exchange chromatography were analyzed for ability to hydrolyze alkali treated carrot grass (ATCG) in the presence of Mn(2+)/Cu(2+). This strategy in tandem with peptide mass fingerprinting led to identification of metal dependent protein hydrolases with no apparent hydrolytic activity, however, showed 5.7 folds higher saccharification in presence of Mn(2+). Furthermore, adding different protein fractions to commercial cellulase (Novozymes: Cellic CTec2) resulted in enhanced hydrolysis of ATCG ranging between 1.57 and 3.43 folds indicating the enzymes from M. cinnamomea as catalytically efficient. PMID:26476165

  11. Novel glycoside hydrolases from thermophilic fungi

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to isolated polypeptides having cellulolytic activity or hemicellulolytic activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of produ...

  12. BIOTECHNOLOGY OF TRICHODERMA-BASED FEED ADDITIVE WITH CELLULOLYTIC PROPERTIES

    Directory of Open Access Journals (Sweden)

    Koshchayev A. G.

    2013-11-01

    Full Text Available In the work, we have presented the information of elaboration of a manufacturing process of Mycocel feed additive with the cellulolytic activity for poul-try industry. Manufacturing process includes follow-ing steps: stock culture maintenance and storage of Trichoderma lignorum 81-17, growing fluid culture of microscopic fungus in sucrose yeast extract me-dium, feed additive with cellulolytic properties out-put and quality control, packaging, storage and disposal of waste. We have shown that the Mycocel is non-toxic feed additive for protozoa and warm-blooded animals (laboratory mice and quails. This study demonstrated total population livability in the experimental group with feed additive. Quail body-weight of experimental group was higher by 6% as compared to the control and feed consumption per 1 kg of live weight of bird was 3,58 kg, 7,5% lower than the control

  13. Cost-effective production of biotechnologically important hydrolytic enzymes by Sporotrichum thermophile.

    Science.gov (United States)

    Bala, Anju; Singh, Bijender

    2016-01-01

    Economical production of xylanase and three cellulases, endo-β-1,4-glucanase (CMCase), exo-β-1,4-glucanase (FPase), β-glucosidase (BGL) was studied in submerged fermentation using cane molasses medium. A statistical optimization approach involving Plackett-Burman design and response surface methodology (RSM) resulted in the production of 72,410, 36,420, 32,420 and 5180 U/l of xylanase, CMCase, FPase and β-glucosidase, respectively. Optimization resulted in more than fourfold improvements in production of xylanolytic and cellulolytic enzymes. Scale up of enzymes production in shake flasks of varied volumes was sustainable, suggesting a good scope for large scale enzyme production. Addition of microparticles engineered fungal morphology and enhanced enzymes production. Xylanase of S. thermophile is a neutral xylanase displaying its optimal activity at 60 °C while all the cellulases are optimally active at pH 5.0 and 60 °C. The efficacy of enzyme cocktail in waste tea cup paper and rice straw hydrolysis showed that maximum sugar yield of 578.12 and 421.79 mg/g substrate for waste tea cup and rice straw, respectively, were achieved after 24 h. Therefore, concomitant production of cellulolytic and xylanolytic enzymes will be beneficial for the saccharification of lignocellulosics in generating both monomeric and oligomeric sugars for biofuels and other biotechnological applications.

  14. Cost-effective production of biotechnologically important hydrolytic enzymes by Sporotrichum thermophile.

    Science.gov (United States)

    Bala, Anju; Singh, Bijender

    2016-01-01

    Economical production of xylanase and three cellulases, endo-β-1,4-glucanase (CMCase), exo-β-1,4-glucanase (FPase), β-glucosidase (BGL) was studied in submerged fermentation using cane molasses medium. A statistical optimization approach involving Plackett-Burman design and response surface methodology (RSM) resulted in the production of 72,410, 36,420, 32,420 and 5180 U/l of xylanase, CMCase, FPase and β-glucosidase, respectively. Optimization resulted in more than fourfold improvements in production of xylanolytic and cellulolytic enzymes. Scale up of enzymes production in shake flasks of varied volumes was sustainable, suggesting a good scope for large scale enzyme production. Addition of microparticles engineered fungal morphology and enhanced enzymes production. Xylanase of S. thermophile is a neutral xylanase displaying its optimal activity at 60 °C while all the cellulases are optimally active at pH 5.0 and 60 °C. The efficacy of enzyme cocktail in waste tea cup paper and rice straw hydrolysis showed that maximum sugar yield of 578.12 and 421.79 mg/g substrate for waste tea cup and rice straw, respectively, were achieved after 24 h. Therefore, concomitant production of cellulolytic and xylanolytic enzymes will be beneficial for the saccharification of lignocellulosics in generating both monomeric and oligomeric sugars for biofuels and other biotechnological applications. PMID:26581490

  15. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

    Directory of Open Access Journals (Sweden)

    Lizeth Manuela Avellaneda-Torres

    2014-12-01

    Full Text Available A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP, Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS of ribosomal DNA for fungi. Multivariate statistical analysis (MVA was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  16. Compositions comprising a polypeptide having cellulolytic enhancing activity and a dioxy compound and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, Matthew; Xu, Feng; Quinlan, Jason

    2016-07-19

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a dioxy compound. The present invention also relates to methods of using the compositions.

  17. Compositions comprising a polypeptide having cellulolytic enhancing activity and a bicyclic compound and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Quinlan, Jason; Xu, Feng; Sweeney, Matthew

    2016-10-04

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a bicyclic compound. The present invention also relates to methods of using the compositions.

  18. Compositions comprising a polypeptide having cellulolytic enhancing activity and a heterocyclic compound and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Feng; Sweeney, Matthew; Quinlan, Jason

    2016-08-02

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a heterocyclic compound. The present invention also relates to methods of using the compositions.

  19. Compositions comprising a polypeptide having cellulolytic enhancing activity and a bicycle compound and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Feng; Sweeney, Matthew; Quinlan, Jason

    2015-06-16

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a bicyclic compound. The present invention also relates to methods of using the compositions.

  20. Thermophilic anaerobic digestion for waste and wastewater treatment.

    NARCIS (Netherlands)

    Wiegant, W.M.

    1986-01-01

    This thesis deals with thermophilic anaerobic waste and wastewater treatment. A literature survey is presented, in which the thermophilic treatment processes are evaluated with respect to the loading rates and treatment efficiencies, and some relevant theoretical considerations concerning thermophil

  1. Ethanol production by engineered thermophiles.

    Science.gov (United States)

    Olson, Daniel G; Sparling, Richard; Lynd, Lee R

    2015-06-01

    We compare a number of different strategies that have been pursued to engineer thermophilic microorganisms for increased ethanol production. Ethanol production from pyruvate can proceed via one of four pathways, which are named by the key pyruvate dissimilating enzyme: pyruvate decarboxylase (PDC), pyruvate dehydrogenase (PDH), pyruvate formate lyase (PFL), and pyruvate ferredoxin oxidoreductase (PFOR). For each of these pathways except PFL, we see examples where ethanol production has been engineered with a yield of >90% of the theoretical maximum. In each of these cases, this engineering was achieved mainly by modulating expression of native genes. We have not found an example where a thermophilic ethanol production pathway has been transferred to a non-ethanol-producing organism to produce ethanol at high yield. A key reason for the lack of transferability of ethanol production pathways is the current lack of understanding of the enzymes involved. PMID:25745810

  2. Production and Optimization of Exo and Endocellulases from Thermophilic Fungi Scytalidium thermophilum SKESMBKU02

    Directory of Open Access Journals (Sweden)

    Sriyamjalla SANTOSHKUMAR

    2016-01-01

    Full Text Available The study aimed at isolation and screening of thermophilic cellulase producer, optimization and stability studies for maximum cellulase production. Fifteen thermophilic cellulase producing fungi were isolated from thermogenic habitats (vegetable market compost, mushroom compost, horse dung, municipal waste, nests of birds, decomposing litter, soils from furnace area, cattle dung, zoo dump, and industrial waste. of Telangana. All the fungal isolates were screened for their ability to produce cellulases. Scytalidium thermophilum SKESMBKU02 showed the highest cellulase activity in screening and was selected for further studies. The results showed that S. thermophilum SKESMBKU02 found to have high cellulolytic activity at 45 °C and pH 5.0 - 6.0. Optimization of enzyme production was studied in different carbon and nitrogen sources. The endo and exoglucanase activities were higher in media containing glucose as their carbon source followed by xylose. Yeast extract and peptone were good nitrogen sources for endoglucanase and exoglucanase activity respectively. The organism showed maximum dry weight in (NH42SO4 and NH4Cl. The exo and endocellulases produced by the S. thermophilum SKESMBKU02 were highly stable at pH 8.0 and temperature of 75 °C. The results indicate that the endo and exocellulases produced by the fungi were more stable at high temperature and alkaline pH.

  3. Cellulose hydrolysis by fungi. 1. Screening of cellulolytic strains

    Energy Technology Data Exchange (ETDEWEB)

    Roussos, S.; Raimbault, M. (Laboratoire de Microbiologie ORSTOM, Centre de Recherche IRCHA, 91 - Vert-le-Petit (France))

    Trichoderma harzianum was selected from 30 strains of cellulolytic fungi with the aim of producing cellulases by solid state fermentation of lignocellulosic substrates. Special attention was paid to cellulase production (i. e. carboxymethylcellulase and filter paper activity), apical growth and conidia production. Under the conditions of our experiments, T. harzianum exhibited the highest cellulasic activities with 1,315 IU/I of carboxymethyl cellulose and 80 IU/l of filter paper activity. Apical growth (1 mm/h) and yield of conidial production (3.25 X 10/sup 10/ conidia/g of substrate dry weight) were also valuable characteristics of this strain in the use of solid state fermentation.

  4. Ultrasound-mediated DNA transformation in thermophilic gram-positive anaerobes.

    Directory of Open Access Journals (Sweden)

    Lu Lin

    Full Text Available BACKGROUND: Thermophilic, Gram-positive, anaerobic bacteria (TGPAs are generally recalcitrant to chemical and electrotransformation due to their special cell-wall structure and the low intrinsic permeability of plasma membranes. METHODOLOGY/PRINCIPAL FINDINGS: Here we established for any Gram-positive or thermophiles an ultrasound-based sonoporation as a simple, rapid, and minimally invasive method to genetically transform TGPAs. We showed that by applying a 40 kHz ultrasound frequency over a 20-second exposure, Texas red-conjugated dextran was delivered with 27% efficiency into Thermoanaerobacter sp. X514, a TGPA that can utilize both pentose and hexose for ethanol production. Experiments that delivered plasmids showed that host-cell viability and plasmid DNA integrity were not compromised. Via sonoporation, shuttle vectors pHL015 harboring a jellyfish gfp gene and pIKM2 encoding a Clostridium thermocellum β-1,4-glucanase gene were delivered into X514 with an efficiency of 6x10(2 transformants/µg of methylated DNA. Delivery into X514 cells was confirmed via detecting the kanamycin-resistance gene for pIKM2, while confirmation of pHL015 was detected by visualization of fluorescence signals of secondary host-cells following a plasmid-rescue experiment. Furthermore, the foreign β-1,4-glucanase gene was functionally expressed in X514, converting the host into a prototypic thermophilic consolidated bioprocessing organism that is not only ethanologenic but cellulolytic. CONCLUSIONS/SIGNIFICANCE: In this study, we developed an ultrasound-based sonoporation method in TGPAs. This new DNA-delivery method could significantly improve the throughput in developing genetic systems for TGPAs, many of which are of industrial interest yet remain difficult to manipulate genetically.

  5. Biochemical characterization of thermophilic lignocellulose degrading enzymes and their potential for biomass bioprocessing

    Directory of Open Access Journals (Sweden)

    Vasudeo Zambare, Archana Zambare, Kasiviswanath Muthukumarappan, Lew P. Christopher

    2011-01-01

    Full Text Available A thermophilic microbial consortium (TMC producing hydrolytic (cellulolytic and xylanolytic enzymes was isolated from yard waste compost following enrichment with carboxymethyl cellulose and birchwood xylan. When grown on 5% lignocellulosic substrates (corn stover and prairie cord grass at 600C, the thermophilic consortium produced more xylanase (up to 489 U/l on corn stover than cellulase activity (up to 367 U/l on prairie cord grass. Except for the carboxymethyl cellulose-enriched consortium, thermo-mechanical extrusion pretreatment of these substrates had a positive effect on both activities with up to 13% and 21% increase in the xylanase and cellulase production, respectively. The optimum temperatures of the crude cellulase and xylanase were 600C and 700C with half-lives of 15 h and 18 h, respectively, suggesting higher thermostability for the TMC xylanase. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the crude enzyme exhibited protein bands of 25-77 kDa with multiple enzyme activities containing 3 cellulases and 3 xylanases. The substrate specificity declined in the following descending order: avicel>birchwood xylan>microcrystalline cellulose>filter paper>pine wood saw dust>carboxymethyl cellulose. The crude enzyme was 77% more active on insoluble than soluble cellulose. The Km and Vmax values were 36.49 mg/ml and 2.98 U/mg protein on avicel (cellulase, and 22.25 mg/ml and 2.09 U/mg protein, on birchwood xylan (xylanase. A total of 50 TMC isolates were screened for cellulase and xylanase secretion on agar plates. All single isolates showed significantly lower enzyme activities when compared to the thermophilic consortia. This is indicative of the strong synergistic interactions that exist within the thermophilic microbial consortium and enhance its hydrolytic capabilities. It was further demonstrated that the thermostable enzyme-generated lignocellulosic hydrolyzates can be fermented to bioethanol by a recombinant strain of

  6. Biochemical characterization of thermophilic lignocellulose degrading enzymes and their potential for biomass bioprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Zambare, Vasudeo; Zambare, Archana; Christopher, Lew P. [Center for Bioprocessing Research & Development, South Dakota School of Mines and Technology, Rapid City 57701, SD (United States); Muthukumarappan, Kasiviswanath [Center for Bioprocessing Research & Development, South Dakota State University, Brookings 57007, SD (United States)

    2011-07-01

    A thermophilic microbial consortium (TMC) producing hydrolytic (cellulolytic and xylanolytic) enzymes was isolated from yard waste compost following enrichment with carboxymethyl cellulose and birchwood xylan. When grown on 5% lignocellulosic substrates (corn stover and prairie cord grass) at 60C, the thermophilic consortium produced more xylanase (up to 489 U/l on corn stover) than cellulase activity (up to 367 U/l on prairie cord grass). Except for the carboxymethyl cellulose-enriched consortium, thermo-mechanical extrusion pretreatment of these substrates had a positive effect on both activities with up to 13% and 21% increase in the xylanase and cellulase production, respectively. The optimum temperatures of the crude cellulase and xylanase were 60C and 70C with half-lives of 15 h and 18 h, respectively, suggesting higher thermostability for the TMC xylanase. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the crude enzyme exhibited protein bands of 25-77 kDa with multiple enzyme activities containing 3 cellulases and 3 xylanases. The substrate specificity declined in the following descending order: avicel>birchwood xylan>microcrystalline cellulose>filter paper>pine wood saw dust>carboxymethyl cellulose. The crude enzyme was 77% more active on insoluble than soluble cellulose. The Km and Vmax values were 36.49 mg/ml and 2.98 U/mg protein on avicel (cellulase), and 22.25 mg/ml and 2.09 U/mg protein, on birchwood xylan (xylanase). A total of 50 TMC isolates were screened for cellulase and xylanase secretion on agar plates. All single isolates showed significantly lower enzyme activities when compared to the thermophilic consortia. This is indicative of the strong synergistic interactions that exist within the thermophilic microbial consortium and enhance its hydrolytic capabilities. It was further demonstrated that the thermostable enzyme-generated lignocellulosic hydrolyzates can be fermented to bioethanol by a recombinant strain of Escherichia coli

  7. An Efficient and Improved Methodology for the Screening of Industrially Valuable Xylano-Pectino-Cellulolytic Microbes

    Directory of Open Access Journals (Sweden)

    Avtar Singh

    2015-01-01

    Full Text Available Xylano-pectino-cellulolytic enzymes are valuable enzymes of the industrial sector. In our earlier study, we have reported a novel and cost effective methodology for the qualitative screening of cellulase-free xylano-pectinolytic microorganisms by replacing the commercial, highly expensive substrates with agricultural residues, but the microorganisms with xylanolytic, pectinolytic, cellulolytic, xylano-pectinolytic, xylano-cellulolytic, pectino-cellulolytic, and xylano-pectino-cellulolytic potential were obtained. The probability of getting the desired combination was low, so efforts were made to further improve this cost effective methodology for obtaining the high yield of the microbes capable of producing desired combination of enzymes. By inclusion of multiple enrichment steps in sequence, using only practically low cost substrates and without any nutrient media till primary screening stage, this improved novel protocol for screening gave only the desired microorganisms with xylano-pectino-cellulolytic activity. Using this rapid, efficient, cost effective, and improved methodology, microbes with required combination of enzymes can be obtained and the probability of getting the desired microorganisms is cent percent. This is the first report presenting the methodology for the isolation of xylano-pectino-cellulolytic positive microorganisms at low cost and consuming less time.

  8. An efficient and improved methodology for the screening of industrially valuable xylano-pectino-cellulolytic microbes.

    Science.gov (United States)

    Singh, Avtar; Kaur, Amanjot; Dua, Anita; Mahajan, Ritu

    2015-01-01

    Xylano-pectino-cellulolytic enzymes are valuable enzymes of the industrial sector. In our earlier study, we have reported a novel and cost effective methodology for the qualitative screening of cellulase-free xylano-pectinolytic microorganisms by replacing the commercial, highly expensive substrates with agricultural residues, but the microorganisms with xylanolytic, pectinolytic, cellulolytic, xylano-pectinolytic, xylano-cellulolytic, pectino-cellulolytic, and xylano-pectino-cellulolytic potential were obtained. The probability of getting the desired combination was low, so efforts were made to further improve this cost effective methodology for obtaining the high yield of the microbes capable of producing desired combination of enzymes. By inclusion of multiple enrichment steps in sequence, using only practically low cost substrates and without any nutrient media till primary screening stage, this improved novel protocol for screening gave only the desired microorganisms with xylano-pectino-cellulolytic activity. Using this rapid, efficient, cost effective, and improved methodology, microbes with required combination of enzymes can be obtained and the probability of getting the desired microorganisms is cent percent. This is the first report presenting the methodology for the isolation of xylano-pectino-cellulolytic positive microorganisms at low cost and consuming less time. PMID:25692034

  9. Compositions for enhancing hydroysis of cellulosic material by cellulolytic enzyme compositions

    Science.gov (United States)

    Quinlan, Jason; Xu, Feng; Sweeney, Matthew; Johansen, Katja Salomon

    2014-09-30

    The present invention relates to compositions comprising a GH61 polypeptide having cellulolytic enhancing activity and an organic compound comprising a carboxylic acid moiety, a lactone moiety, a phenolic moiety, a flavonoid moiety, or a combination thereof, wherein the combination of the GH61 polypeptide having cellulolytic enhancing activity and the organic compound enhances hydrolysis of a cellulosic material by a cellulolytic enzyme compared to the GH61 polypeptide alone or the organic compound alone. The present invention also relates to methods of using the compositions.

  10. NREL Explains the Higher Cellulolytic Activity of a Vital Microorganism

    Energy Technology Data Exchange (ETDEWEB)

    2016-06-01

    The discovery of a new mode of action by C. thermocellum to convert biomass to biofuels is significant because the bacterium is already recognized as one of the most effective in the biosphere. Researchers found that, in addition to using common cellulase degradation mechanisms attached to cells, C. thermocellum also uses a new category of cell-free scaffolded enzymes. The new discovery will influence the strategies used to improve the cellulolytic activity of biomass degrading microbes going forward. Better understanding of this bacterium could lead to cheaper production of ethanol and drop-in fuels. Also, this discovery demonstrates that nature's biomass conversion behaviors are not fully understood and remain as opportunities for future microbial/enzyme engineering efforts.

  11. SACCHARIFICATION OF CORNCOB USING CELLULOLYTIC BACTERIA FOR BIOETHANOL PRODUCTION

    Directory of Open Access Journals (Sweden)

    TITI CANDRA SUNARTI

    2010-08-01

    Full Text Available The use of cellulose degrading enzyme (cellulases for hydrolysis of lignocellulosic material is a part of bioethanol production process. In this experiment, delignified corncob, its cellulose fraction and alpha cellulose were used as substrates to produce fermentable sugar by using three local isolates of celluloytic bacteria (C5-1, C4-4, C11-1 and Cmix ; mixed cultures of three isolates, and Saccharomyces cereviseae to produce ethanol. The results showed that all isolates of cellulolytic bacteria can grow on cellulose fraction better than on delignified corncob, and alpha cellulose. The highest hydrolytic activity produced from cellulose fraction was by isolate C4-4, which liberated 3.50 g/l of total sugar. Ethanol can be produced by mixed culture of bacteria and yeast, but because of competitive growth, the fermentation only produced 0.39-0.47 g/l of ethanol.

  12. Characterization of cellulolytic activities of environmental bacterial consortia from an Argentinian native forest.

    Science.gov (United States)

    Romano, Nelson; Gioffré, Andrea; Sede, Silvana M; Campos, Eleonora; Cataldi, Angel; Talia, Paola

    2013-08-01

    Cellulolytic activities of three bacterial consortia derived from a forest soil sample from Chaco region, Argentina, were characterized. The phylogenetic analysis of consortia revealed two main highly supported groups including Achromobacter and Pseudomonas genera. All three consortia presented cellulolytic activity. The carboxymethylcellulase (CMCase) and total cellulase activities were studied both quantitatively and qualitatively and optimal enzymatic conditions were characterized and compared among the three consortia. Thermal and pH stability were analyzed. Based on its cellulolytic activity, one consortium was selected for further characterization by zymography. We detected a specific protein of 55 kDa with CMCase activity. In this study, we have shown that these consortia encode for cellulolytic enzymes. These enzymes could be useful for lignocellulosic biomass degradation into simple components and for different industrial applications. PMID:23471693

  13. Insight into Dominant Cellulolytic Bacteria from Two Biogas Digesters and Their Glycoside Hydrolase Genes

    OpenAIRE

    Yongjun Wei; Haokui Zhou; Jun Zhang; Lei Zhang; Alei Geng; Fanghua Liu; Guoping Zhao; Shengyue Wang; Zhihua Zhou; Xing Yan

    2015-01-01

    Diverse cellulolytic bacteria are essential for maintaining high lignocellulose degradation ability in biogas digesters. However, little was known about functional genes and gene clusters of dominant cellulolytic bacteria in biogas digesters. This is the foundation to understand lignocellulose degradation mechanisms of biogas digesters and apply these gene resource for optimizing biofuel production. A combination of metagenomic and 16S rRNA gene clone library methods was used to investigate t...

  14. Consolidated bioprocessing method using thermophilic microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Mielenz, Jonathan Richard

    2016-02-02

    The present invention is directed to a method of converting biomass to biofuel, and particularly to a consolidated bioprocessing method using a co-culture of thermophilic and extremely thermophilic microorganisms which collectively can ferment the hexose and pentose sugars produced by degradation of cellulose and hemicelluloses at high substrate conversion rates. A culture medium therefor is also provided as well as use of the methods to produce and recover cellulosic ethanol.

  15. The significance of cellulolytic enzymes produced by Trichoderma in opportunistic lifestyle of this fungus.

    Science.gov (United States)

    Strakowska, Judyta; Błaszczyk, Lidia; Chełkowski, Jerzy

    2014-07-01

    The degradation of native cellulose to glucose monomers is a complex process, which requires the synergistic action of the extracellular enzymes produced by cellulolytic microorganisms. Among fungi, the enzymatic systems that can degrade native cellulose have been extensively studied for species belonging to the genera of Trichoderma. The majority of the cellulolytic enzymes described so far have been examples of Trichoderma reesei, extremely specialized in the efficient degradation of plant cell wall cellulose. Other Trichoderma species, such as T. harzianum, T. koningii, T. longibrachiatum, and T. viride, known for their capacity to produce cellulolytic enzymes, have been isolated from various ecological niches, where they have proved successful in various heterotrophic interactions. As saprotrophs, these species are considered to make a contribution to the degradation of lignocellulosic plant material. Their cellulolytic potential is also used in interactions with plants, especially in plant root colonization. However, the role of cellulolytic enzymes in species forming endophytic associations with plants or in those existing in the substratum for mushroom cultivation remains unknown. The present review discusses the current state of knowledge about cellulolytic enzymes production by Trichoderma species and the encoding genes, as well as the involvement of these proteins in the lifestyle of Trichoderma.

  16. Variations of culturable thermophilic microbe numbers and bacterial communities during the thermophilic phase of composting.

    Science.gov (United States)

    Li, Rong; Li, Linzhi; Huang, Rong; Sun, Yifei; Mei, Xinlan; Shen, Biao; Shen, Qirong

    2014-06-01

    Composting is a process of stabilizing organic wastes through the degradation of biodegradable components by microbial communities under controlled conditions. In the present study, genera and species diversities, amylohydrolysis, protein and cellulose degradation abilities of culturable bacteria in the thermophilic phase of composting of cattle manure with plant ash and rice bran were investigated. The number of culturable thermophilic bacteria and actinomyces decreased with the increasing temperature. At the initiation and end of the thermophilic phase, genera and specie diversities and number of bacteria possessing degradation abilities were higher than during the middle phase. During the thermophilic composting phase, Bacillus, Geobacillus and Ureibacillus were the dominant genera, and Geobacillus thermodenitrificans was the dominant species. In later thermophilic phases, Geobacillus toebii and Ureibacillus terrenus were dominant. Bacillus, at the initiation, and Ureibacillus and Geobacillus, at the later phase, contributed the multiple degradation abilities. These data will facilitate the control of composting in the future. PMID:24415499

  17. Insight into Dominant Cellulolytic Bacteria from Two Biogas Digesters and Their Glycoside Hydrolase Genes.

    Directory of Open Access Journals (Sweden)

    Yongjun Wei

    Full Text Available Diverse cellulolytic bacteria are essential for maintaining high lignocellulose degradation ability in biogas digesters. However, little was known about functional genes and gene clusters of dominant cellulolytic bacteria in biogas digesters. This is the foundation to understand lignocellulose degradation mechanisms of biogas digesters and apply these gene resource for optimizing biofuel production. A combination of metagenomic and 16S rRNA gene clone library methods was used to investigate the dominant cellulolytic bacteria and their glycoside hydrolase (GH genes in two biogas digesters. The 16S rRNA gene analysis revealed that the dominant cellulolytic bacteria were strains closely related to Clostridium straminisolvens and an uncultured cellulolytic bacterium designated BG-1. To recover GH genes from cellulolytic bacteria in general, and BG-1 in particular, a refined assembly approach developed in this study was used to assemble GH genes from metagenomic reads; 163 GH-containing contigs ≥ 1 kb in length were obtained. Six recovered GH5 genes that were expressed in E. coli demonstrated multiple lignocellulase activities and one had high mannanase activity (1255 U/mg. Eleven fosmid clones harboring the recovered GH-containing contigs were sequenced and assembled into 10 fosmid contigs. The composition of GH genes in the 163 assembled metagenomic contigs and 10 fosmid contigs indicated that diverse GHs and lignocellulose degradation mechanisms were present in the biogas digesters. In particular, a small portion of BG-1 genome information was recovered by PhyloPythiaS analysis. The lignocellulase gene clusters in BG-1 suggested that it might use a possible novel lignocellulose degradation mechanism to efficiently degrade lignocellulose. Dominant cellulolytic bacteria of biogas digester possess diverse GH genes, not only in sequences but also in their functions, which may be applied for production of biofuel in the future.

  18. Insight into Dominant Cellulolytic Bacteria from Two Biogas Digesters and Their Glycoside Hydrolase Genes.

    Science.gov (United States)

    Wei, Yongjun; Zhou, Haokui; Zhang, Jun; Zhang, Lei; Geng, Alei; Liu, Fanghua; Zhao, Guoping; Wang, Shengyue; Zhou, Zhihua; Yan, Xing

    2015-01-01

    Diverse cellulolytic bacteria are essential for maintaining high lignocellulose degradation ability in biogas digesters. However, little was known about functional genes and gene clusters of dominant cellulolytic bacteria in biogas digesters. This is the foundation to understand lignocellulose degradation mechanisms of biogas digesters and apply these gene resource for optimizing biofuel production. A combination of metagenomic and 16S rRNA gene clone library methods was used to investigate the dominant cellulolytic bacteria and their glycoside hydrolase (GH) genes in two biogas digesters. The 16S rRNA gene analysis revealed that the dominant cellulolytic bacteria were strains closely related to Clostridium straminisolvens and an uncultured cellulolytic bacterium designated BG-1. To recover GH genes from cellulolytic bacteria in general, and BG-1 in particular, a refined assembly approach developed in this study was used to assemble GH genes from metagenomic reads; 163 GH-containing contigs ≥ 1 kb in length were obtained. Six recovered GH5 genes that were expressed in E. coli demonstrated multiple lignocellulase activities and one had high mannanase activity (1255 U/mg). Eleven fosmid clones harboring the recovered GH-containing contigs were sequenced and assembled into 10 fosmid contigs. The composition of GH genes in the 163 assembled metagenomic contigs and 10 fosmid contigs indicated that diverse GHs and lignocellulose degradation mechanisms were present in the biogas digesters. In particular, a small portion of BG-1 genome information was recovered by PhyloPythiaS analysis. The lignocellulase gene clusters in BG-1 suggested that it might use a possible novel lignocellulose degradation mechanism to efficiently degrade lignocellulose. Dominant cellulolytic bacteria of biogas digester possess diverse GH genes, not only in sequences but also in their functions, which may be applied for production of biofuel in the future.

  19. Bioleaching of marmatite using moderately thermophilic bacteria

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hong-bo; LIU Fei-fei; ZOU Ying-qin; ZENG Xiao-xi; QIU Guan-zhou

    2008-01-01

    The process of bioleaching marmatite using moderately thermophilic bacteria was studied by comparing marmatite leaching performance of mesophiles and moderate thermophiles and valuating the effect of venting capacity as well as pulp density on marmatite leaching performance of moderate thermophiles. The results show that moderate thermophiles have more advantages over mesophilies in bioleaching marmatite at 45℃ and the pulp density of 50g/L, and the zinc extraction efficiency reaches 93.1% in 20d. Aeration agitation can improve the transfer of O2 and CO2 in solution and promote the growth of bacteria and therefore, enhance the leaching efficiency. Under the venting levels of 50, 200 and 800mL/min, the zinc extraction efficiencies by moderate thermophiles are 57.8%, 92.5% and 96.0%, respectively. With the increase of pulp density, the total leaching amount of valuable metals increases, however, the extraction efficiency decreases due to many reasons, such as increasing shear force leading to poorly growth condition for bacteria, etc. The zinc extraction decreases remarkably to 58.9% while the pulp density mounts up 20%.

  20. Status on Science and Application of Thermophilic Anaerobic Digestion

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær

    1994-01-01

    Thermophilic anaerobic processes are often regarded as less stable than mesophilic processes. In the paper this postulate is examined and disproved based on real operational data from of full-scale mesophilic and thermophilic biogas plants. The start-up produce for the thermophilic plants was, ho...

  1. Bioprospecting thermophiles for cellulase production: a review

    Directory of Open Access Journals (Sweden)

    Somen Acharya

    2012-09-01

    Full Text Available Most of the potential bioprospecting is currently related to the study of the extremophiles and their potential use in industrial processes. Recently microbial cellulases find applications in various industries and constitute a major group of industrial enzymes. Considerable amount of work has been done on microbial cellulases, especially with resurgence of interest in biomass ethanol production employing cellulases and use of cellulases in textile and paper industry. Most efficient method of lignocellulosic biomass hydrolysis is through enzymatic saccharification using cellulases. Significant information has also been gained about the physiology of thermophilic cellulases producers and process development for enzyme production and biomass saccharification. The review discusses the current knowledge on cellulase producing thermophilic microorganisms, their physiological adaptations and control of cellulase gene expression. It discusses the industrial applications of thermophilic cellulases, their cost of production and challenges in cellulase research especially in the area of improving process economics of enzyme production.

  2. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives.

    Science.gov (United States)

    Bielen, Abraham A M; Verhaart, Marcel R A; van der Oost, John; Kengen, Servé W M

    2013-01-17

    Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit for dark fermentation of 4 mol hydrogen per mol hexose, this organism has proven itself to be an excellent candidate for biological hydrogen production. This review provides an overview of the research on C. saccharolyticus with respect to the hydrolytic capability, sugar metabolism, hydrogen formation, mechanisms involved in hydrogen inhibition, and the regulation of the redox and carbon metabolism. Analysis of currently available fermentation data reveal decreased hydrogen yields under non-ideal cultivation conditions, which are mainly associated with the accumulation of hydrogen in the liquid phase. Thermodynamic considerations concerning the reactions involved in hydrogen formation are discussed with respect to the dissolved hydrogen concentration. Novel cultivation data demonstrate the sensitivity of C. saccharolyticus to increased hydrogen levels regarding substrate load and nitrogen limitation. In addition, special attention is given to the rhamnose metabolism, which represents an unusual type of redox balancing. Finally, several approaches are suggested to improve biohydrogen production by C. saccharolyticus.

  3. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives

    Directory of Open Access Journals (Sweden)

    Servé W. M. Kengen

    2013-01-01

    Full Text Available Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit for dark fermentation of 4 mol hydrogen per mol hexose, this organism has proven itself to be an excellent candidate for biological hydrogen production. This review provides an overview of the research on C. saccharolyticus with respect to the hydrolytic capability, sugar metabolism, hydrogen formation, mechanisms involved in hydrogen inhibition, and the regulation of the redox and carbon metabolism. Analysis of currently available fermentation data reveal decreased hydrogen yields under non-ideal cultivation conditions, which are mainly associated with the accumulation of hydrogen in the liquid phase. Thermodynamic considerations concerning the reactions involved in hydrogen formation are discussed with respect to the dissolved hydrogen concentration. Novel cultivation data demonstrate the sensitivity of C. saccharolyticus to increased hydrogen levels regarding substrate load and nitrogen limitation. In addition, special attention is given to the rhamnose metabolism, which represents an unusual type of redox balancing. Finally, several approaches are suggested to improve biohydrogen production by C. saccharolyticus.

  4. Isolation and Identification of Cellulolytic Bacteria from the Gut of Three Phytophagus Insect Species

    Directory of Open Access Journals (Sweden)

    Rajib Kumar Shil

    2014-12-01

    Full Text Available The cellulolytic bacteria from the gut of three different phytophagous insects were studied to isolate novel cellulolytic organism for biofuel industry. Among the threse, gut of P. quatuordecimpunctata larvae contained both highest no of total bacterial count (6.8x107CFU/gut and cellulolytic bacteria (5.42x103CFU/gut. Fifteen different isolates were obtained from the gut of O. velox, A. miliarisand P. quatuordecimpunctata. All the isolates produced clear zone in CMC medium staining with Congo red. The isolates included Gram positive Enterococcus, Microbacterium and Gram negative Aeromonas, Erwinia, Serretia, Flavobacterium, Acenitobacter, Klebsiella, Yersinia, Xenorhabdus, Psedomonas and Photorhabdus. Out of the fifteen isolated and identified bacterial species, twelve bacterial species were novel being reported for first time as having cellulase activity.

  5. PGASO: A synthetic biology tool for engineering a cellulolytic yeast

    Directory of Open Access Journals (Sweden)

    Chang Jui-Jen

    2012-07-01

    Full Text Available Abstract Background To achieve an economical cellulosic ethanol production, a host that can do both cellulosic saccharification and ethanol fermentation is desirable. However, to engineer a non-cellulolytic yeast to be such a host requires synthetic biology techniques to transform multiple enzyme genes into its genome. Results A technique, named Promoter-based Gene Assembly and Simultaneous Overexpression (PGASO, that employs overlapping oligonucleotides for recombinatorial assembly of gene cassettes with individual promoters, was developed. PGASO was applied to engineer Kluyveromycesmarxianus KY3, which is a thermo- and toxin-tolerant yeast. We obtained a recombinant strain, called KR5, that is capable of simultaneously expressing exoglucanase and endoglucanase (both of Trichodermareesei, a beta-glucosidase (from a cow rumen fungus, a neomycin phosphotransferase, and a green fluorescent protein. High transformation efficiency and accuracy were achieved as ~63% of the transformants was confirmed to be correct. KR5 can utilize beta-glycan, cellobiose or CMC as the sole carbon source for growth and can directly convert cellobiose and beta-glycan to ethanol. Conclusions This study provides the first example of multi-gene assembly in a single step in a yeast species other than Saccharomyces cerevisiae. We successfully engineered a yeast host with a five-gene cassette assembly and the new host is capable of co-expressing three types of cellulase genes. Our study shows that PGASO is an efficient tool for simultaneous expression of multiple enzymes in the kefir yeast KY3 and that KY3 can serve as a host for developing synthetic biology tools.

  6. Technique for preparation of anaerobic microbes: Rodshaped cellulolytic bacteria

    Directory of Open Access Journals (Sweden)

    Amlius Thalib

    2001-10-01

    Full Text Available Preparation of anaerobic-rod cellulolytic bacteria with coating technique has been conducted. Steps of the processes involved were cultivation, coating, evaporation, and drying. Coating agent used was Gum Arabic, and drying techniquesconducted were freeze drying and sun drying. pH of culture media was firstly optimized to obtain the maximal population ofbacteria. Both coated and uncoated preparates were subjected to drying. Morphological and Gram type identifications showed that uncoated preparate dried with freeze drying is not contaminated (ie. all bacteria are rod shape with Gram-negative type while the one dried with sun drying is not morphologically pure (ie. containing of both rod and coccus shapes with Gram negative and positive. The coated preparates dried by both freeze and sun drying, were not contaminated (ie. all are rods with Gram-negative. The coating and drying processes decreased viability of preparates significantly. However, the decreasing of viability of coated preparate are lower than uncoated preparate (ie. 89 vs. 97%. Total count of bacteria in sun-drying coated preparate are higher (P<0.05 than the uncoated preparate (ie. 3.38 x 1010 vs. 1.97 x 1010 colony/g DM. Activity of sun-drying coated preparate to digest elephant grass and rice straw was higher (P<0.01 than the sun-drying uncoated preparate with the in vitro DMD values were 42.7 vs. 35.5% for elephant grass substrate and 29.3 vs. 24.6% for rice straw substrate. Therefore, it is concluded that coating technique has a positive effects on the preparation of rumen bacteria.

  7. Relationship between soil cellulolytic activity and suppression of seedling blight of barley in arable soils

    DEFF Research Database (Denmark)

    Rasmussen, Peter Have; Knudsen, I.; Elmholt, S.;

    2002-01-01

    The objective was to investigate the relationship between soil suppression of seedling blight of barley caused by Fusarium culmorum (W.G. Smith) Sacc. and the soil cellulolytic activity of beta-glucosidase, cellobiohydrolase and endocellulase. Disease suppression was investigated in bioassays....... From the preliminary results obtained, it is proposed that the cellulolytic activity can be used as an enzymatic approach to study the microbial turnover of organic matter in soils and as indicator of seedling blight of barley caused by F. culmorum. (C) 2002 Elsevier Science B.V. All rights reserved....

  8. Are thermophilic microorganisms active in cold environments?

    Science.gov (United States)

    Cockell, Charles S.; Cousins, Claire; Wilkinson, Paul T.; Olsson-Francis, Karen; Rozitis, Ben

    2015-07-01

    The mean air temperature of the Icelandic interior is below 10 °C. However, we have previously observed 16S rDNA sequences associated with thermophilic lineages in Icelandic basalts. Measurements of the temperatures of igneous rocks in Iceland showed that solar insolation of these low albedo substrates achieved a peak surface temperature of 44.5 °C. We isolated seven thermophilic Geobacillus species from basalt with optimal growth temperatures of ~65 °C. The minimum growth temperature of these organisms was ~36 °C, suggesting that they could be active in the rock environment. Basalt dissolution rates at 40 °C were increased in the presence of one of the isolates compared to abiotic controls, showing its potential to be involved in active biogeochemistry at environmental temperatures. These data raise the possibility of transient active thermophilic growth in macroclimatically cold rocky environments, implying that the biogeographical distribution of active thermophiles might be greater than previously understood. These data show that temperatures measured or predicted over large scales on a planet are not in themselves adequate to assess niches available to extremophiles at micron scales.

  9. Thermophilic starter cultures: another set of problems

    OpenAIRE

    Oberg, C. J.; Broadbent, Jeffery R.

    1993-01-01

    Increased consumer demand for yogurt and Italian cheeses, particularly Mozzarella, over the past decade has intensified production demands on thermophilic starter cultures. Dramatically elevated production rates within existing facilities have created problems analogous to those experienced years ago by the dairy industry for mesophilic lactococci when Cheddar cheese production increased dramatically. In contrast to mesophilic lactococci, however, diversity among lactic genera that contain th...

  10. A thermophilic microbial fuel cell design

    Science.gov (United States)

    Carver, Sarah M.; Vuoriranta, Pertti; Tuovinen, Olli H.

    Microbial fuel cells (MFCs) are reactors able to generate electricity by capturing electrons from the anaerobic respiratory processes of microorganisms. While the majority of MFCs have been tested at ambient or mesophilic temperatures, thermophilic systems warrant evaluation because of the potential for increased microbial activity rates on the anode. MFC studies at elevated temperatures have been scattered, using designs that are already established, specifically air-cathode single chambers and two-chamber designs. This study was prompted by our previous attempts that showed an increased amount of evaporation in thermophilic MFCs, adding unnecessary technical difficulties and causing excessive maintenance. In this paper, we describe a thermophilic MFC design that prevents evaporation. The design was tested at 57 °C with an anaerobic, thermophilic consortium that respired with glucose to generate a power density of 375 mW m -2 after 590 h. Polarization and voltage data showed that the design works in the batch mode but the design allows for adoption to continuous operation.

  11. Sample handling factors affecting the enumeration of lactobacilli and cellulolytic bacteria in equine feces

    Science.gov (United States)

    The objectives were to compare media types and evaluate the effects of fecal storage time and temperature on the enumeration of cellulolytic bacteria and lactobacilli from horses. Fecal samples were collected from horses (n = 3) and transported to the lab (CO2, 37 ºC, 0.5 h). The samples were assign...

  12. [Biosynthesis of cellulolytic enzymes and xylanase during submerged cultivation of the fungus Aspergillus terreus 17P].

    Science.gov (United States)

    Loginova, L G; Guzhova, E P; Ismanlova, D Iu; Burdenko, L G

    1978-01-01

    The fungus Aspergillus terreus 17P--producer of cellulolytic enzymes--was cultivated in the Biotec 10 l fermenter on the medium containing minced and heated (at 200 degrees) wheat straw aerated with a different rate. At the mixing rate of 350 rpm and aeration rate of 0.7 r/rpm on the fourth day the culture liquid was obtained whose filtrate contained an active complex of cellulolytic enzymes and xylanase: CI--3.4; APB--1.1, Cx--35.7, cellobiase--0.23, xylanase--73.8 units/ml. The fractionation of the culture liquid filtrate with ammonium sulphate showed that the fraction precipitated at an interval of saturation of 0.3--0.7 contained the largest portion of cellulolytic enzymes and xylanase. The isolated enzymic preparations had a cellulolytic and xylanase activity and contained lipase, pectinase, laminarinase. They also contained low quantities of amylase, protease, beta-1,4- and beta-1,6-glucanase. Enzymic hylrolysis by the Asp. terreus 17P preparation of straw yielded glucose and xylose, of cotton, Na-KMC, cellobiose--glucose, Xylane hydrolyzate contained xylose and arabinose.

  13. Determination of the cellulolytic activities of microorganisms isolated from poultry litter for sawdust degradation

    Directory of Open Access Journals (Sweden)

    Akpomie O.OF

    2013-03-01

    Full Text Available Cellulolytic activities of bacterial and fungal isolates obtained from poultry droppings were determined using the ability of each isolate to produce clear zones on Carboxyl Methyl Cellulose Agar plates. The bacterial isolates were Klebsiella, Streptococcus, Celulomonas, Escherichia coli and Micrococus species. The cellulolytic counts ranged from 5.02 x 104 + 3.42 to 7.20 x 109 + 6.12 cfu/g. The cellulolytic activities of the bacterial isolates ranged from 0.04 to 0.26 iu/m with Cellulomonas having the highest cellulose activity. The fungal isolates were Aspergillus niger, Mucor mucedo, Trichoderma sp. and Penicllium chrysogenum with cellulose activities of 0.24 + 0.021 0.19 + 0.031, 0.23 + 0.05 and 0.23 + 0.028iu/ml respectively. All the isolates were able to degrade the sawdust to varying extent. The percentage degradation was highest with Micrococcus sp. (78.20% and least with Trichoderma sp. (65.83%. The study shows that is a potential source of cellulolytic microorganisms which could be employed in the degradation of sawdust.

  14. The occurrence and distribution of cellulolytic fungi and Fusarium in seven Montagu’s Harrier (Circus pygargus

    Directory of Open Access Journals (Sweden)

    Teresa Korniłłowicz-Kowalska

    2013-12-01

    Full Text Available A total of 45 species of cellulolytic fungi and ten Fusarium species were identified. Three genera (Chaetomium, Trichoderma, Fusarium represented 80% of the frequency of cellulolytic fungi. Of them, Chaetomium globosum, Trichoderma viride and T. koningii were some of the most frequent species. A high differentiation of the richness and frequency of species of cellulolytic fungi depending on the nest and its individual layers was observed. Reasons for the differences in the frequency and species composition of the fungi were discussed.

  15. Discrimination of thermophilic and mesophilic proteins

    Directory of Open Access Journals (Sweden)

    Vaisman Iosif I

    2010-05-01

    Full Text Available Abstract Background There is a considerable literature on the source of the thermostability of proteins from thermophilic organisms. Understanding the mechanisms for this thermostability would provide insights into proteins generally and permit the design of synthetic hyperstable biocatalysts. Results We have systematically tested a large number of sequence and structure derived quantities for their ability to discriminate thermostable proteins from their non-thermostable orthologs using sets of mesophile-thermophile ortholog pairs. Most of the quantities tested correspond to properties previously reported to be associated with thermostability. Many of the structure related properties were derived from the Delaunay tessellation of protein structures. Conclusions Carefully selected sequence based indices discriminate better than purely structure based indices. Combined sequence and structure based indices improve performance somewhat further. Based on our analysis, the strongest contributors to thermostability are an increase in ion pairs on the protein surface and a more strongly hydrophobic interior.

  16. Thermophilic biohydrogen production: how far are we?

    Science.gov (United States)

    Pawar, Sudhanshu S; van Niel, Ed W J

    2013-09-01

    Apart from being applied as an energy carrier, hydrogen is in increasing demand as a commodity. Currently, the majority of hydrogen (H2) is produced from fossil fuels, but from an environmental perspective, sustainable H2 production should be considered. One of the possible ways of hydrogen production is through fermentation, in particular, at elevated temperature, i.e. thermophilic biohydrogen production. This short review recapitulates the current status in thermophilic biohydrogen production through fermentation of commercially viable substrates produced from readily available renewable resources, such as agricultural residues. The route to commercially viable biohydrogen production is a multidisciplinary enterprise. Microbiological studies have pointed out certain desirable physiological characteristics in H2-producing microorganisms. More process-oriented research has identified best applicable reactor types and cultivation conditions. Techno-economic and life cycle analyses have identified key process bottlenecks with respect to economic feasibility and its environmental impact. The review has further identified current limitations and gaps in the knowledge, and also deliberates directions for future research and development of thermophilic biohydrogen production. PMID:23948723

  17. Thermophilic methane production and oxidation in compost.

    Science.gov (United States)

    Jäckel, Udo; Thummes, Kathrin; Kämpfer, Peter

    2005-04-01

    Methane cycling within compost heaps has not yet been investigated in detail. We show that thermophilic methane oxidation occurred after a lag phase of up to one day in 4-week old, 8-week old and mature (>10-week old) compost material. The potential rate of methane oxidation was between 2.6 and 4.1 micromol CH4(gdw)(-1)h(-1). Profiles of methane concentrations within heaps of different ages indicated that 46-98% of the methane produced was oxidised by methanotrophic bacteria. The population size of thermophilic methanotrophs was estimated at 10(9) cells (gdw)(-1), based on methane oxidation rates. A methanotroph (strain KTM-1) was isolated from the highest positive step of a serial dilution series. This strain belonged to the genus Methylocaldum, which contains thermotolerant and thermophilic methanotrophs. The closest relative organism on the basis of 16S rRNA gene sequence identity was M. szegediense (>99%), a species originally isolated from hot springs. The temperature optimum (45-55 degrees C) for methane oxidation within the compost material was identical to that of strain KTM-1, suggesting that this strain was well adapted to the conditions in the compost material. The temperatures measured in the upper layer (0-40 cm) of the compost heaps were also in this range, so we assume that these organisms are capable of effectively reducing the potential methane emissions from compost.

  18. Thermophilic biohydrogen production: how far are we?

    Science.gov (United States)

    Pawar, Sudhanshu S; van Niel, Ed W J

    2013-09-01

    Apart from being applied as an energy carrier, hydrogen is in increasing demand as a commodity. Currently, the majority of hydrogen (H2) is produced from fossil fuels, but from an environmental perspective, sustainable H2 production should be considered. One of the possible ways of hydrogen production is through fermentation, in particular, at elevated temperature, i.e. thermophilic biohydrogen production. This short review recapitulates the current status in thermophilic biohydrogen production through fermentation of commercially viable substrates produced from readily available renewable resources, such as agricultural residues. The route to commercially viable biohydrogen production is a multidisciplinary enterprise. Microbiological studies have pointed out certain desirable physiological characteristics in H2-producing microorganisms. More process-oriented research has identified best applicable reactor types and cultivation conditions. Techno-economic and life cycle analyses have identified key process bottlenecks with respect to economic feasibility and its environmental impact. The review has further identified current limitations and gaps in the knowledge, and also deliberates directions for future research and development of thermophilic biohydrogen production.

  19. Compositions comprising a polypeptide having cellulolytic enhancing activity and a nitrogen-containing compound and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Quinlan, Jason; Xu, Feng; Sweeney, Matthew

    2016-05-31

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a nitrogen-containing compound. The present invention also relates to methods of using the compositions.

  20. Heterologous Acidothermus cellulolyticus 1,4-β-Endoglucanase E1 Produced Within the Corn Biomass Converts Corn Stover Into Glucose

    Science.gov (United States)

    Ransom, Callista; Balan, Venkatesh; Biswas, Gadab; Dale, Bruce; Crockett, Elaine; Sticklen, Mariam

    Commercial conversion of lignocellulosic biomass to fermentable sugars requires inexpensive bulk production of biologically active cellulase enzymes, which might be achieved through direct production of these enzymes within the biomass crops. Transgenic corn plants containing the catalytic domain of Acidothermus cellulolyticus E1 endo-1,4-β glucanase and the bar bialaphos resistance coding sequences were generated after Biolistic® (BioRad Hercules, CA) bombardment of immature embryo-derived cells. E1 sequences were regulated under the control of the cauliflower mosaic virus 35S promoter and tobacco mosaic virus translational enhancer, and E1 protein was targeted to the apoplast using the signal peptide of tobacco pathogenesis-related protein to achieve accumulation of this enzyme. The integration, expression, and segregation of E1 and bar transgenes were demonstrated, respectively, through Southern and Western blotting, and progeny analyses. Accumulation of up to 1.13% of transgenic plant total soluble proteins was detected as biologically active E1 by enzymatic activity assay. The corn-produced, heterologous E1 could successfully convert ammonia fiber explosion-pretreated corn stover polysaccharides into glucose as a fermentable sugar for ethanol production, confirming that the E1 enzyme is produced in its active from.

  1. Thermophilic anaerobic waste water treatment, temperature aspects and process stability.

    NARCIS (Netherlands)

    Lier, van J.B.

    1995-01-01

    The main objective of this thesis was to assess the thermostability of thermophilic anaerobic wastewater treatment processes and the possibility to optimize the performance of thermophilic high-rate systems.Experiments were conducted to study the suitability of two types of seed material to start a

  2. Thermophillic Sidestream Anaerobic Membrane Bioreactors: The Shear Rate Dilemma

    NARCIS (Netherlands)

    Jeison, D.A.; Telkamp, P.; Lier, van J.B.

    2009-01-01

    Anaerobic biomass retention under thermophilic conditions has proven difficult. Membrane filtration can be used as alternative way to achieve high sludge concentrations. This research studied the feasibility of anaerobic membrane bioreactors (AnMBRs) under thermophilic conditions. A sidestream MBR w

  3. Deciphering the molecular mechanisms behind cellulase production in Trichoderma reesei, the hyper-cellulolytic filamentous fungus.

    Science.gov (United States)

    Shida, Yosuke; Furukawa, Takanori; Ogasawara, Wataru

    2016-09-01

    The filamentous fungus Trichoderma reesei is a potent cellulase producer and the best-studied cellulolytic fungus. A lot of investigations not only on glycoside hydrolases produced by T. reesei, but also on the machinery controlling gene expression of these enzyme have made this fungus a model organism for cellulolytic fungi. We have investigated the T. reesei strain including mutants developed in Japan in detail to understand the molecular mechanisms that control the cellulase gene expression, the biochemical and morphological aspects that could favor this phenotype, and have attempted to generate novel strains that may be appropriate for industrial use. Subsequently, we developed recombinant strains by combination of these insights and the heterologous-efficient saccharifing enzymes. Resulting enzyme preparations were highly effective for saccharification of various biomass. In this review, we present some of the salient findings from the recent biochemical, morphological, and molecular analyses of this remarkable cellulase hyper-producing fungus. PMID:27075508

  4. Thermophilic anaerobic digestion: the best option for waste treatment.

    Science.gov (United States)

    Suryawanshi, P C; Chaudhari, A B; Kothari, R M

    2010-03-01

    After introducing thermophilic anaerobic digestion (AD), characteristics of thermophilic methanogens are provided. Accordingly, (a) site of occurrence, (b) morphological characteristics (shape and motility), (c) biochemical characteristics (Gram character and % G+C profile), (d) nutritional characteristics (NaCl requirement and substrate specificity), and (e) growth characteristics (pH and temperature) of thermophilic methanogens are described. Some studies of the thermophilic AD are cited with their operational management problems. Subsequently, strategies to maximize net energy production are given, including mode of heating the bioreactors, role of agitation to promote AD performance and mode/intensity of mixing. Finally, advantages as well as drawbacks of AD under thermophilic conditions are given, concluding with its applications. PMID:20148754

  5. Paenibacillus curdlanolyticus Strain B-6 Xylanolytic-Cellulolytic Enzyme System That Degrades Insoluble Polysaccharides

    OpenAIRE

    Pason, Patthra; Kyu, Khin Lay; Ratanakhanokchai, Khanok

    2006-01-01

    A facultatively anaerobic bacterium, Paenibacillus curdlanolyticus B-6, isolated from an anaerobic digester produces an extracellular xylanolytic-cellulolytic enzyme system containing xylanase, β-xylosidase, arabinofuranosidase, acetyl esterase, mannanase, carboxymethyl cellulase (CMCase), avicelase, cellobiohydrolase, β-glucosidase, amylase, and chitinase when grown on xylan under aerobic conditions. During growth on xylan, the bacterial cells were found to adhere to xylan from the early exp...

  6. Cellulolytic enzymes on lignocellulosic substrates in solid state fermentation by Aspergillus niger

    OpenAIRE

    Chandra, M. Subhosh; Viswanath, Buddolla; Reddy, B. Rajasekhar

    2007-01-01

    The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days. The peak production of the...

  7. Enrichment and characterization of an anaerobic cellulolytic microbial consortium SQD-1.1 from mangrove soil.

    Science.gov (United States)

    Gao, Zhao-Ming; Xu, Xun; Ruan, Ling-Wei

    2014-01-01

    Enrichment of microbial consortia provides an approach to simulate and investigate microbial communities in natural environments. In this study, a cellulolytic microbial consortium SQD-1.1 was enriched from mangrove soil of Qinglan port (Hainan, China) by 27 times continuous subcultivation under anaerobic static conditions. The consortium could completely degrade 0.2% (w/v) filter paper within 3 days and utilized it as the sole carbon source. PCR-denaturing gradient gel electrophoresis analysis revealed a stable microbial community structure in the incubation process of 10 days and in the procedure of subcultivation. Twenty-four operational taxonomic units belonging to seven phyla were obtained from the full-length 16S rRNA gene library. Five clones, closest related to the genera Alkaliflexus, Clostridium, Alistipes, Spirochaeta, and Trichococcus, were the predominant ones. Among them, M117, phylogeneticly showing high similarity (16S rRNA gene identity, 95.3%) with the cellulolytic anaerobic bacterium Clostridium straminisolvens CSK1(T), was the potential key cellulolytic bacterium. Using the plate cultivation method, 12 strains, including one potential new species and four potential new species of new genera, were isolated. The strain P2, corresponding to the most frequently detected clone (M05) in the 16S rRNA gene library, showed both CMCase and xylanase activity and may be another important cellulolytic bacterium. The findings of cellulase activity in cell pellet and cohesion and dockerin domains in metagenome data further suggested the potential of utilization of cellulosomes by the consortium to degrade cellulose. Consortium SQD-1.1 provides a candidate for investigating the mechanism of cellulose degradation under anoxic conditions in natural environments. PMID:23529681

  8. Hydrophobic nature and effects of culture conditions on biofilm formation by the cellulolytic actinomycete Thermobifida fusca

    Directory of Open Access Journals (Sweden)

    Almaris N. Alonso

    2015-09-01

    Full Text Available Thermobifida fusca produces a firmly attached biofilm on nutritive and non-nutritive surfaces, such as cellulose, glass, plastic, metal and Teflon®. The ability to bind to surfaces has been suggested as a competitive advantage for microbes in soil environments. Results of previous investigations indicated that a Gram-positive cellulolytic soil bacteria, Cellulomonas uda, a facultative aerobe, specifically adhered to nutritive surfaces forming biofilms, but cells did not colonize non-nutritive surfaces. Cell surface hydrophobicity has been implicated in the interactions between bacteria and the adhesion to surfaces. It was recently described that the cellulolytic actinomycete T. fusca cells hydrophobicity was measured and compared to the cellulolytic soil bacteria C. uda. Also, T. fusca biofilm formation on non-nutritive surface, such as polyvinyl chloride, was examined by testing various culture ingredients to determine a possible trigger mechanism for biofilm formation. Experimental results showed that partitioning of bacterial cells to various hydrocarbons was higher in T. fusca cells than in C. uda. The results of this study suggest that the attachment to multiple surfaces by T. fusca could depend on nutrient availability, pH, salt concentrations, and the higher hydrophobic nature of bacterial cells. Possibly, these characteristics may confer T. fusca a selective advantage to compete and survive among the many environments it thrives.

  9. Enhancing the cellulose-degrading activity of cellulolytic bacteria CTL-6 (Clostridium thermocellum) by co-culture with non-cellulolytic bacteria W2-10 (Geobacillus sp.).

    Science.gov (United States)

    Lü, Yucai; Li, Ning; Yuan, Xufeng; Hua, Binbin; Wang, Jungang; Ishii, Masaharu; Igarashi, Yasuo; Cui, Zongjun

    2013-12-01

    The effect of a non-cellulolytic bacterium W2-10 (Geobacillus sp.) on the cellulose-degrading activity of a cellulolytic bacterium CTL-6 (Clostridium thermocellum) was determined using cellulose materials (paper and straw) in peptone cellulose solution (PCS) medium under aerobic conditions. The results indicated that in the co-culture, addition of W2-10 resulted in a balanced medium pH, and may provide the required anaerobic environment for CTL-6. Overall, addition of W2-10 was beneficial to CTL-6 growth in the adverse environment of the PCS medium. In co-culture with W2-10, the CTL-6 cellulose degradation efficiency of filter paper and alkaline-treated wheat straw significantly increased up to 72.45 and 37.79 %, respectively. The CMCase activity and biomass of CTL-6 also increased from 0.23 U ml(-1) and 45.1 μg ml(-1) (DNA content) up to 0.47 U ml(-1) and 112.2 μg ml(-1), respectively. In addition, co-culture resulted in accumulation of acetate and propionate up to 4.26 and 2.76 mg ml(-1). This was a respective increase of 2.58 and 4.45 times, in comparison to the monoculture with CTL-6.

  10. Bio-hydrogen production in an EGSB reactor under mesophilic, thermophilic and hyperthermophilic conditions

    OpenAIRE

    Abreu, A. A.; Danko, Anthony S.; Alves, M. M.

    2007-01-01

    Mesophilic, thermophilic and hyperthermophilic bio-hydrogen production with an expanded granular sludge blanket (EGSB) fed with glucose and arabinose, without methane production, was demonstrated. Homoacetogenesis was observed on reactor when operated under mesophilic (37ºC) conditions but not under thermophilic (55ºC) and hyper-thermophilic conditions (70ºC). It was also found that under thermophilic and hyper-thermophilic conditions glucose is preferentially consumed than ara...

  11. Aerobic Thermophilic Composting of Municipal Solid Waste

    Directory of Open Access Journals (Sweden)

    D V Wadkar

    2013-03-01

    Full Text Available Composting is a natural process that turns organic material into a dark rich substance called compost. Aerobic Composting is the creation of compost that depends on bacteria that thrive in an oxygen rich environment. Aerobic bacteria manage the chemical process by converting the inputs (i.e. air, water and carbon and nitrogen rich materials into heat, carbon dioxide and ammonium. The ammonium is further converted by bacteria into plant nourishing nitrites and nitrates through the process of nitrification. Thermophilic Composting is breaking down biological waste with thermophilic (heat loving bacteria. A cylindrical reactor was made. Organic wasteincluded dry vegetable waste collected from MSW ramp, Koregaon park, Pune. The characteristics of compost like pH, moisture content, temperature, C/N ratio and volume reduction were studied for the period of maturation (42days. It can be concluded that the values are within the desired limits and compost is suitable for ornamental plants. The setup of reactor is affordable and thus the compost obtained is effective and economical.

  12. Optimization of Acidothermus Celluloyticus Endoglucanase (E1) Production in Transgenic Tobacco Plants by Transcriptional, Post-transcription and Post-Translational Modification

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Hooker, Brian S.; Quesenberry, Ryan D.; Thomas, S. R.

    2005-10-01

    Biochemical characteristics of Acidothermus cellulolyticus endoglucanase (E1) and its physiological effects in transgenic tobacco (Nicotiana tabacum) has been studied previously. In an attempt to obtain a high level of production of intact E1 in transgenic plants, the E1 gene was expressed under the control of strong Mac promoter (a hybrid promoter of manopine synthase promoter and cauliflower mosaic virus 35S promoter enhancer region) or tomato Rubisco small subunit (RbcS-3C) promoter with different 5’ untranslated leader (UTL) sequence and targeted to different subcellular comartmentations with various transit peptides. The expression of E1 protein in transgenic tobacco plants was determined via E1 activity, protein immunobloting, and RNA gel-blotting analyses. Effects of different transit peptides on E1 protein production and its stability were examined in transgenic tobacco plants carrying one of six transgene expression vectors with the same (Mac) promoter and transcription terminator (Tmas). Transgenic tobacco plants with apoplast transit peptide (Mm-apo) had the highest average E1 activity and protein accumulation , while E1 protein was more stable in transgenic plants with no transit peptide (Mm) than others. The E1 expression under tomato RbcS-3C promoter was higher than that under Mac promoter based on the average E1 activity, E1 protein accumulation, and RNA gel-blotting. The E1 expression was increased more than two fold when the 5’-UTL of alfalfa mosaic virus RNA4 gene replaced the UTL of RbcS-3C promoter, while the UTL of alfalfa mosaic virus RNA4 gene was less effective than the UTL of Mac promoter. The optimal combination of promoter, 5’-UTL, and subcellular compartmentation (transit peptide) for E1 protein production in transgenic tobacco plants are discussed.

  13. Comparison of the thermostability of cellulases from various thermophilic fungi

    Energy Technology Data Exchange (ETDEWEB)

    Wojtczak, G.; Breuil, C.; Yamada, J.; Saddler, J.N.

    1987-10-01

    The cellulase activities of six thermophilic fungi were compared. Although the thermophilic fungi grew at relatively high temperatures (> 45/sup 0/C) the optimum temperatures for assaying the various cellulase activities were only slightly higher than the optimum temperatures for the mesophilic fungi, Trichoderma harzianum. Over prolonged incubation (> 24 h) the thermophilic strains demonstrated a higher hydrolytic potential as a result of the greater thermostability of the cellulase components. Although the extracellular cellulase activities had similar pH and temperature optima, in some cases the thermostability of the extracellular components were considerably lower.

  14. Thermophilic Sulfate-Reducing Bacteria in Cold Marine Sediment

    DEFF Research Database (Denmark)

    ISAKSEN, MF; BAK, F.; JØRGENSEN, BB

    1994-01-01

    P60, were isolated and characterized as Desulfotomaculum kuznetsovii. The temperature response of growth and respiration of strain P60 agreed well with the measured sulfate reduction at 50 degrees-70 degrees C. Bacteria similar to strain P60 could thus be responsible for the measured thermophilic...... C to search for presence of psychrophilic, mesophilic and thermophilic sulfate-reducing bacteria. Detectable activity was initially only in the mesophilic range, but after a lag phase sulfate reduction by thermophilic sulfate-reducing bacteria were observed. No distinct activity of psychrophilic...... sulfate-reducing bacteria was detected. Time course experiments showed constant sulfate reduction rates at 4 degrees C and 30 degrees C, whereas the activity at 60 degrees C increased exponentially after a lag period of one day. Thermophilic, endospore-forming sulfate-reducing bacteria, designated strain...

  15. Global Association between Thermophilicity and Vancomycin Susceptibility in Bacteria.

    Science.gov (United States)

    Roy, Chayan; Alam, Masrure; Mandal, Subhrangshu; Haldar, Prabir K; Bhattacharya, Sabyasachi; Mukherjee, Trinetra; Roy, Rimi; Rameez, Moidu J; Misra, Anup K; Chakraborty, Ranadhir; Nanda, Ashish K; Mukhopadhyay, Subhra K; Ghosh, Wriddhiman

    2016-01-01

    Exploration of the aquatic microbiota of several circum-neutral (6.0-8.5 pH) mid-temperature (55-85°C) springs revealed rich diversities of phylogenetic relatives of mesophilic bacteria, which surpassed the diversity of the truly-thermophilic taxa. To gain insight into the potentially-thermophilic adaptations of the phylogenetic relatives of Gram-negative mesophilic bacteria detected in culture-independent investigations we attempted pure-culture isolation by supplementing the enrichment media with 50 μg ml(-1) vancomycin. Surprisingly, this Gram-positive-specific antibiotic eliminated the entire culturable-diversity of chemoorganotrophic and sulfur-chemolithotrophic bacteria present in the tested hot water inocula. Moreover, it also killed all the Gram-negative hot-spring isolates that were obtained in vancomycin-free media. Concurrent literature search for the description of Gram-negative thermophilic bacteria revealed that at least 16 of them were reportedly vancomycin-susceptible. While these data suggested that vancomycin-susceptibility could be a global trait of thermophilic bacteria (irrespective of their taxonomy, biogeography and Gram-character), MALDI Mass Spectroscopy of the peptidoglycans of a few Gram-negative thermophilic bacteria revealed that tandem alanines were present in the fourth and fifth positions of their muropeptide precursors (MPPs). Subsequent phylogenetic analyses revealed a close affinity between the D-alanine-D-alanine ligases (Ddl) of taxonomically-diverse Gram-negative thermophiles and the thermostable Ddl protein of Thermotoga maritima, which is well-known for its high specificity for alanine over other amino acids. The Ddl tree further illustrated a divergence between the homologs of Gram-negative thermophiles and mesophiles, which broadly coincided with vancomycin-susceptibility and vancomycin-resistance respectively. It was thus hypothesized that thermophilic Ddls have been evolutionarily selected to favor a D-ala-D-ala bonding

  16. Global association between thermophilicity and vancomycin susceptibility in bacteria

    Directory of Open Access Journals (Sweden)

    Chayan eRoy

    2016-03-01

    Full Text Available Exploration of the aquatic microbiota of several circum-neutral (6.0-8.5 pH mid-temperature (55-85 OC springs revealed rich diversities of phylogenetic relatives of mesophilic bacteria, which surpassed the diversity of the truly-thermophilic taxa. To gain insight into the potentially-thermophilic adaptations of the phylogenetic relatives of Gram-negative mesophilic bacteria detected in culture-independent investigations we attempted pure-culture isolation by supplementing the enrichment media with 50 µg ml-1 vancomycin. Surprisingly, this Gram-positive-specific antibiotic eliminated the entire culturable-diversity of chemoorganotrophic and sulfur-chemolithotrophic bacteria present in the tested hot water inocula. Moreover, it also killed all the Gram-negative hot-spring isolates that were obtained in vancomycin-free media. Concurrent literature search for the description of Gram-negative thermophilic bacteria revealed that at least 16 of them were reportedly vancomycin-susceptible. While these data suggested that vancomycin-susceptibility could be a global trait of thermophilic bacteria (irrespective of their taxonomy, biogeography and Gram-character, MALDI Mass Spectroscopy of the peptidoglycans of a few Gram-negative thermophilic bacteria revealed that tandem alanines were present in the fourth and fifth positions of their muropeptide precursors (MPPs. Subsequent phylogenetic analyses revealed a close affinity between the D-alanine-D-alanine ligases (Ddl of taxonomically-diverse Gram-negative thermophiles and the thermostable Ddl protein of Thermotoga maritima, which is well-known for its high specificity for alanine over other amino acids. The Ddl tree further illustrated a divergence between the homologs of Gram-negative thermophiles and mesophiles, which broadly coincided with vancomycin-susceptibility and vancomycin-resistance respectively. It was thus hypothesized that thermophilic Ddls have been evolutionarily selected to favor a D

  17. Enzymatic activity of the cellulolytic complex produced by Trichoderma reesei. Enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    The enzymatic activity characterization of the cellulolytic complex obtained from Trichoderma reesei QM 9414 and the influence of the enzymatic hydrolysis conditions on the hydrolysis yield are studied. Pure cellulose and native or alkali pretreated biomass Onopordum nervosum have been used as substrates. The values of pH, temperature, substrate concentration and enzyme-substrate ratio for the optimum activity of that complex, evaluated as glucose and reducing sugars production, have been selected. Previous studies on enzymatic hydrolysis of 0. nervosum have shown a remarkable effect of the alkaline pretreatments on the final hydrolysis yield. (Author) 10 refs

  18. Enzymatic activity of the cellulolytic complex produced by trichoderma reesei. Enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    The enzymatic activity characterization of the cellulolytic complex obtained from Trichoderma reese QM 9414 and the influence of the enzymatic hydrolysis conditions on the hydrolysis yield are studied. Pure cellulose and native or alkali pretreated biomass from Onopordum nervosum have been used as substrates. The values of pH, temperature, substrate concentration and enzyme-substrate ratio for the optimum activity of that complex, evaluated as glucose and reducing sugars productions, have been selected. Previous studies on enzymatic hydrolysis of O. nervosum have shown a remarkable effect of the alkaline pretreatments on the final hydrolysis yield. (author). 10 figs.; 10 refs

  19. Performance of mesophilic biohydrogen-producing cultures at thermophilic conditions.

    Science.gov (United States)

    Gupta, Medhavi; Gomez-Flores, Maritza; Nasr, Noha; Elbeshbishy, Elsayed; Hafez, Hisham; Hesham El Naggar, M; Nakhla, George

    2015-09-01

    In this study, batch tests were conducted to investigate the performance of mesophilic anaerobic digester sludge (ADS) at thermophilic conditions and estimate kinetic parameters for co-substrate fermentation. Starch and cellulose were used as mono-substrate and in combination as co-substrates (1:1 mass ratio) to conduct a comparative assessment between mesophilic (37 °C) and thermophilic (60 °C) biohydrogen production. Unacclimatized mesophilic ADS responded well to the temperature change. The highest hydrogen yield of 1.13 mol H2/mol hexose was observed in starch-only batches at thermophilic conditions. The thermophilic cellulose-only yield (0.42 mol H2/mol hexose) was three times the mesophilic yield (0.13 mol H2/mol hexose). Interestingly, co-fermentation of starch-cellulose at mesophilic conditions enhanced the hydrogen yield by 26% with respect to estimated mono-substrate yields, while under thermophilic conditions no enhancement in the overall yield was observed. Interestingly, the estimated overall Monod kinetic parameters showed higher rates at mesophilic than thermophilic conditions.

  20. Optimization of Acidothermus cellulolyticus endoglucanase (E1) production in transgenic tobacco plants by transcriptional, post-transcription and post-translational modification.

    Science.gov (United States)

    Dai, Ziyu; Hooker, Brian S; Quesenberry, Ryan D; Thomas, Steven R

    2005-10-01

    An attempt was made to obtain a high-level production of intact Acidothermus cellulolyticus endoglucanase (E1) in transgenic tobacco plants. The E1 expression was examined under the control of the constitutive and strong Mac promoter or light-inducible tomato Rubisco small sub-unit (RbcS-3C) promoter with its original or Alfalfa Mosaic Virus (AMV) RNA4 5'-untranslated leader (UTL) and targeted to different sub-cellular compartments via transit peptides. The transit peptides included native E1, endoplasmic reticulum, vacuole, apoplast, and chloroplast. E1 expression and its stability in transgenic plants were determined via E1 activity, protein immunoblotting, and RNA gel-blotting analyses. Effects of sub-cellular compartments on E1 production and its stability were determined in transgenic tobacco plants carrying one of six transgene expression vectors, where the E1 was under the control of Mac promoter, mannopine synthase transcription terminator, and one of the five transit peptides. Transgenic tobacco plants with an apoplastic transit peptide had the highest average E1 activity and protein accumulation, which was about 0.25% of total leaf soluble proteins estimated via E1 specific activity and protein gel blots. Intercellular fluid analyses confirmed that E1 signal peptide functioned properly in tobacco cells to secret E1 protein into the apoplast. By replacing RbcS-3C UTL with AMV RNA4 UTL E1 production was enhanced more than twofold, while it was less effective than the mannopine synthase UTL. It was observed that RbcS-3C promoter was more favorable for E1 expression in transgenic plants than the Mac promoter. E1 activity in dried tobacco seeds stored one year at room temperature was 45% higher than that observed immediately after harvesting, suggesting that E1 protein can be stored at room temperature for a long period. E1 stability in different sub-cellular compartments and the optimal combination of promoter, 5'-UTL, and sub-cellular compartmentation for

  1. A potential source for cellulolytic enzyme discovery and environmental aspects revealed through metagenomics of Brazilian mangroves.

    Science.gov (United States)

    Thompson, Claudia Elizabeth; Beys-da-Silva, Walter Orlando; Santi, Lucélia; Berger, Markus; Vainstein, Marilene Henning; Guima Rães, Jorge Almeida; Vasconcelos, Ana Tereza Ribeiro

    2013-01-01

    The mangroves are among the most productive and biologically important environments. The possible presence of cellulolytic enzymes and microorganisms useful for biomass degradation as well as taxonomic and functional aspects of two Brazilian mangroves were evaluated using cultivation and metagenomic approaches. From a total of 296 microorganisms with visual differences in colony morphology and growth (including bacteria, yeast and filamentous fungus), 179 (60.5%) and 117 (39.5%) were isolated from the Rio de Janeiro (RJ) and Bahia (BA) samples, respectively. RJ metagenome showed the higher number of microbial isolates, which is consistent with its most conserved state and higher diversity. The metagenomic sequencing data showed similar predominant bacterial phyla in the BA and RJ mangroves with an abundance of Proteobacteria (57.8% and 44.6%), Firmicutes (11% and 12.3%) and Actinobacteria (8.4% and 7.5%). A higher number of enzymes involved in the degradation of polycyclic aromatic compounds were found in the BA mangrove. Specific sequences involved in the cellulolytic degradation, belonging to cellulases, hemicellulases, carbohydrate binding domains, dockerins and cohesins were identified, and it was possible to isolate cultivable fungi and bacteria related to biomass decomposition and with potential applications for the production of biofuels. These results showed that the mangroves possess all fundamental molecular tools required for building the cellulosome, which is required for the efficient degradation of cellulose material and sugar release.

  2. Cellulolytic enzymes, nucleic acids encoding them and methods for making and using them

    Science.gov (United States)

    Gray, Kevin A.; Zhao, Lishan; Cayouette, Michelle H.

    2012-01-24

    The invention provides polypeptides having any cellulolytic activity, e.g., a cellulase activity, a endoglucanase, a cellobiohydrolase, a beta-glucosidase, a xylanase, a mannanse, a .beta.-xylosidase, an arabinofuranosidase, and/or an oligomerase activity, polynucleotides encoding these polypeptides, and methods of making and using these polynucleotides and polypeptides. In one aspect, the invention is directed to polypeptides having any cellulolytic activity, e.g., a cellulase activity, e.g., endoglucanase, cellobiohydrolase, beta-glucosidase, xylanase, mannanse, .beta.-xylosidase, arabinofuranosidase, and/or oligomerase activity, including thermostable and thermotolerant activity, and polynucleotides encoding these enzymes, and making and using these polynucleotides and polypeptides. In one aspect, the invention provides polypeptides having an oligomerase activity, e.g., enzymes that convert recalcitrant soluble oligomers to fermentable sugars in the saccharification of biomass. The polypeptides of the invention can be used in a variety of pharmaceutical, agricultural, food and feed processing and industrial contexts. The invention also provides compositions or products of manufacture comprising mixtures of enzymes comprising at least one enzyme of this invention.

  3. Flow cytometry community fingerprinting and amplicon sequencing for the assessment of landfill leachate cellulolytic bioaugmentation.

    Science.gov (United States)

    Kinet, R; Dzaomuho, P; Baert, J; Taminiau, B; Daube, G; Nezer, C; Brostaux, Y; Nguyen, F; Dumont, G; Thonart, P; Delvigne, F

    2016-08-01

    Flow cytometry (FCM) is a high throughput single cell technology that is actually becoming widely used for studying phenotypic and genotypic diversity among microbial communities. This technology is considered in this work for the assessment of a bioaugmentation treatment in order to enhance cellulolytic potential of landfill leachate. The experimental results reveal the relevant increase of leachate cellulolytic potential due to bioaugmentation. Cytometric monitoring of microbial dynamics along these assays is then realized. The flow FP package is used to establish microbial samples fingerprint from initial 2D cytometry histograms. This procedure allows highlighting microbial communities' variation along the assays. Cytometric and 16S rRNA gene sequencing fingerprinting methods are then compared. The two approaches give same evidence about microbial dynamics throughout digestion assay. There are however a lack of significant correlation between cytometric and amplicon sequencing fingerprint at genus or species level. Same phenotypical profiles of microbiota during assays matched to several 16S rRNA gene sequencing ones. Flow cytometry fingerprinting can thus be considered as a promising routine on-site method suitable for the detection of stability/variation/disturbance of complex microbial communities involved in bioprocesses. PMID:27160955

  4. Comparative investigations on wood decay and cellulolytic and xylanolytic activity of some basidiomycete fungi

    Energy Technology Data Exchange (ETDEWEB)

    Hegarty, B.; Steinfurth, A.; Liese, W.; Schmidt, O.

    1987-10-01

    To evaluate physiological differences between various wood-decay fungi and especially different strains per species, comparative investigations were performed with 13 brown-rot and 6 white-rot fungi with respect to their wood decay as well as cellulolytic and xylanolytic capacities. Pine wood samples were considerably decayed by the brown-rot fungi with the two Poria placenta strains showing highest and the two Serpula himantioides isolates lowest mass losses. Most white-rot fungi degraded beech wood samples stronger than pine. Schizophyllum commune was inactive on both substrates. Whereas cellulolytic activity measurement using the clearing of Walseth cellulose gave negative results for some brownrotters, all white-rotters, especially Merulius tremellosus produced cellulase. The decay of Remazol Brilliant Blue stained Avicel in liquid medium proved to be an unsuitable test method for most Serpula lacrymans strains, one P. placenta isolate and for Coriolus versicolor and M. tremellosus. The new method of quantitative photometrical determination of dye release from stained cellulose in agar provided a suitable cellulase assay for most fungi, although the whiterotters C. versicolor, Heterobasidion annosum and M. tremellosus could metabolise the stain. In shake culture, carboxymethylcellulase was not produced by S. lacrymans, P. placenta, Laetiporus sulphureus of Gloeophyllum abietinum, whereas all fungi were xylanolytic. There was only a slight relation between wood decay and enzymatic capacity and, altogether, a great physiological diversity within the fungi was evident.

  5. In vitro Cellulose Rich Organic Material Degradation by Cellulolytic Streptomyces albospinus (MTCC 8768

    Directory of Open Access Journals (Sweden)

    Pinky Prasad

    2012-09-01

    Full Text Available Aims: Cellulosic biomass is the only foreseeable sustainable source of fuels and is also one of the dominating waste materials in nature resulting from human activities. Keeping in view the environmental problems like disposal of large volumes of cellulosic wastes and shortage of fossil fuel in the world, the main aim of the present investigation was to characterize and study the cellulolytic activity of Streptomyces albospinus (MTCC 8768, isolated from municipal wastes, on natural cellulosic substrates viz. straw powder, wood powder and finely grated vegetable peels.Methodology and Result: Stanier’s Basal broth with 100 mg of each of the substrates was inoculated separately with S. albospinus (MTCC No. 8768 and incubated at 37 °C for 8 days. The cellulosic substrates were re-weighed at an interval of 2 days and the difference between the initial weight and the final weight gave the amount of substratesdegraded by the isolate. It was observed that maximum degradation was observed in the grated vegetable peels (64 mg followed by straw powder (38 mg and wood powder (28 mg over a period of 8 days.Conclusion, significance and impact of study: By the selection of efficient cellulolytic microorganisms and cost-effective operational techniques, the production of useful end products from the biodegradation of the low cost enormous stock of cellulose in nature can be very beneficial.

  6. Biodegradation of Palm Kernel Cake by Cellulolytic and Hemicellulolytic Bacterial Cultures through Solid State Fermentation

    Directory of Open Access Journals (Sweden)

    Mohamed Idris Alshelmani

    2014-01-01

    Full Text Available Four cellulolytic and hemicellulolytic bacterial cultures were purchased from the Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Culture (DSMZ and the American Type Culture Collection (ATCC. Two experiments were conducted; the objective of the first experiment was to determine the optimum time period required for solid state fermentation (SSF of palm kernel cake (PKC, whereas the objective of the second experiment was to investigate the effect of combinations of these cellulolytic and hemicellulolytic bacteria on the nutritive quality of the PKC. In the first experiment, the SSF was lasted for 12 days with inoculum size of 10% (v/w on different PKC to moisture ratios. In the second experiment, fifteen combinations were created among the four microbes with one untreated PKC as a control. The SSF lasted for 9 days, and the samples were autoclaved, dried, and analyzed for proximate analysis. Results showed that bacterial cultures produced high enzymes activities at the 4th day of SSF, whereas their abilities to produce enzymes tended to be decreased to reach zero at the 8th day of SSF. Findings in the second experiment showed that hemicellulose and cellulose was significantly P<0.05 decreased, whereas the amount of reducing sugars were significantly P<0.05 increased in the fermented PKC (FPKC compared with untreated PKC.

  7. Complete genome sequence of Desulfurococcus fermentans, a hyperthermophilic cellulolytic crenarchaeon isolated from a freshwater hot spring in Kamchatka, Russia.

    Science.gov (United States)

    Susanti, Dwi; Johnson, Eric F; Rodriguez, Jason R; Anderson, Iain; Perevalova, Anna A; Kyrpides, Nikos; Lucas, Susan; Han, James; Lapidus, Alla; Cheng, Jan-Fang; Goodwin, Lynne; Pitluck, Sam; Mavrommatis, Konstantinos; Peters, Lin; Land, Miriam L; Hauser, Loren; Gopalan, Venkat; Chan, Patricia P; Lowe, Todd M; Atomi, Haruyuki; Bonch-Osmolovskaya, Elizaveta A; Woyke, Tanja; Mukhopadhyay, Biswarup

    2012-10-01

    Desulfurococcus fermentans is the first known cellulolytic archaeon. This hyperthermophilic and strictly anaerobic crenarchaeon produces hydrogen from fermentation of various carbohydrates and peptides without inhibition by accumulating hydrogen. The complete genome sequence reported here suggested that D. fermentans employs membrane-bound hydrogenases and novel glycohydrolases for hydrogen production from cellulose.

  8. Complete Genome Sequence of Desulfurococcus fermentans, a Hyperthermophilic Cellulolytic Crenarchaeon Isolated from a Freshwater Hot Spring in Kamchatka, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Susanti, Dwi [Virginia Polytechnic Institute and State University (Virginia Tech); Johnson, Eric F [Virginia Polytechnic Institute and State University (Virginia Tech); Rodriquez, Jason [Virginia Polytechnic Institute and State University (Virginia Tech); Anderson, Iain [U.S. Department of Energy, Joint Genome Institute; Perevalova, Anna [Virginia Polytechnic Institute and State University (Virginia Tech); Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Han, James [U.S. Department of Energy, Joint Genome Institute; Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Cheng, Jan-Fang [U.S. Department of Energy, Joint Genome Institute; Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Mavromatis, K [U.S. Department of Energy, Joint Genome Institute; Peters, Lin [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Gopapan, Venkay [Ohio State University; Chan, Patricia [University of California, Santa Cruz; Atomi, Haruyuki [Kyoto University, Japan; Bonch-Osmolovskaya, Elizaveta [Russian Academy of Sciences, Moscow; Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Mukhopadhyay, Biswarup [Virginia Polytechnic Institute and State University (Virginia Tech)

    2012-01-01

    Desulfurococcus fermentans is the first known cellulolytic archaeon. This hyperthermophilic and strictly anaerobic crenarchaeon produces hydrogen from fermentation of various carbohydrates and peptides without inhibition by accumulating hydrogen. The complete genome sequence reported here suggested that D. fermentans employs membrane-bound hydrogenases and novel glycohydrolases for hydrogen production from cellulose.

  9. Enzymatic Screening and Molecular Characterization of Thermophilic Bacterial Strains Isolated from Hotspring of Tatopani, Bhurung, Nepal

    OpenAIRE

    Hriush Adhikari; Sangam Ghimire; Binod Khatri; Yuvraj K.C.

    2015-01-01

    Background and Aim: In Nepal not much of study of Thermophilic area and Thermophiles have been done. Thermophilic bacteria are less studied but are important group of microorganisms due to their ability to produce industrially important enzymes. Methods: In this study, thermophilic bacteria were isolated from hot spring of Bhurung, Nepal. Wide range of bacteria that could grow at high temperatures and tolerate extreme temperature were characterized by morphology, biochemistry and sequencing o...

  10. Microbial influenced corrosion by thermophilic bacteria

    Science.gov (United States)

    Lata, Suman; Sharma, Chhaya; Singh, Ajay

    2012-03-01

    The present study was undertaken to investigate microbial influenced corrosion (MIC) on stainless steels due to thermophilic bacteria Desulfotomaculum nigrificans. The objective of the study was to measure the extent of corrosion and correlate it with the growth of the biofilm by monitoring the composition of its extracellular polymeric substances (EPS). The toxic effect of heavy metals on MIC was also observed. For this purpose, stainless steels 304L, 316L and 2205 were subjected to electrochemical polarization and immersion tests in the modified Baar's media, control and inoculated, in anaerobic conditions at room temperature. Scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS) were used to identify the chemicals present in/outside the pit. The results show maximum corrosive conditions when bacterial activity is highest, which in turn minimizes the amount of carbohydrate and protein along with the increase in the fraction of uronic acid in carbohydrate in EPS of the biofilm. However, although bacterial activity and corrosion rate decreases, the amount of biofilm components continue to increase. It is also observed that the toxicity of metals ions affect the bacterial activity and EPS production. It was observed that Desulfotomaculum sp. has the ability to biodegrade its own EPS.

  11. An Immunological Assay for Detection and Enumeration of Thermophilic Biomining Microorganisms

    OpenAIRE

    Amaro, Ana M.; Hallberg, Kevin B.; Lindström, E. Börje; Jerez, Carlos A.

    1994-01-01

    A specific, fast, and sensitive nonradioactive immunobinding assay for the detection and enumeration of the moderate thermophile Thiobacillus caldus and the thermophilic archaeon Sulfolobus acidocaldarius was developed. It employs enhanced chemiluminescence or peroxidase-conjugated immunoglobulins in a dot or slot blotting system and is very convenient for monitoring thermophilic bioleaching microorganisms in effluents from industrial bioleaching processes.

  12. Habitat, applications and genomics of the aerobic, thermophilic genus Geobacillus.

    Science.gov (United States)

    McMullan, G; Christie, J M; Rahman, T J; Banat, I M; Ternan, N G; Marchant, R

    2004-04-01

    Thermophilic bacteria belonging to Bacillus genetic group 5 have been reclassified as being members of Geobacillus gen. nov., with G. stearothermophilus as the type strain. Geobacillus species, literally meaning earth or soil Bacillus, are widely distributed and readily isolated from natural and man-made thermophilic biotopes. Work within our group has however shown that an abundance of genetically distinct Geobacillus isolates can be obtained from temperate Irish soils. As with many thermophiles there is considerable interest in potential industrial application of these bacteria and their gene products. This review describes two novel applications for Geobacillus isolates, firstly in the metabolism of the herbicide glyphosate and secondly in the metabolism of quorum-sensing signal molecules from Gram-negative bacteria. Finally the current state of the art is described for Bacillus genomics, with details given of three independent genome-sequencing projects of Geobacillus isolates.

  13. Production of cellulolytic enzymes by Pleurotus species on lignocellulosic wastes using novel pretreatments.

    Science.gov (United States)

    Singh, M P; Pandey, A K; Vishwakarma, S K; Srivastava, A K; Pandey, V K; Singh, V K

    2014-01-01

    In the present investigation three species of Pleurotus i.e. P. sajor—caju (P1), P. florida (P2) and P. flabellatus (P3) along with two lignocellulosic substrates namely paddy straw and wheat straw were selected for evaluation of production of extracellular cellulolytic enzymes. During the cultivation of three species of Pleurotus under in vivo condition, the two lignocellulosic substrates were treated with plants extracts (aqueous extracts of ashoka leaves (A) and neem oil (B)), hot water (H) and chemicals (C).Among all treatments, neem oil treated substrates supported better enzyme production followed by aqueous extract of ashoka leaves, hot water and chemical treatment. Between the two substrates paddy straw supported better enzyme production than wheat straw. P. flabellatus showed maximum activity of exoglucanase, endoglucanase and β—glucosidase followed by P. florida and P. sajor—caju. PMID:25535714

  14. Biological pre-treatment: Enhancing biogas production using the highly cellulolytic fungus Trichoderma viride.

    Science.gov (United States)

    Mutschlechner, Mira; Illmer, Paul; Wagner, Andreas Otto

    2015-09-01

    With regard to renewable sources of energy, bioconversion of lignocellulosic biomass has long been recognized as a desirable endeavor. However, the highly heterogeneous structure of lignocellulose restricts the exploitation of its promising potential in biogas plants. Hence, effective pre-treatment methods are decisive prerequisites to overcome these challenges in order to improve the utilization ratio of (ligno) cellulosic substrates during fermentation. In the present study, the application of Trichoderma viride in an aerobic upstream process prior to anaerobic digestion led up to a threefold increase in the yield of methane and total gas in a lab-scale investigation. Due to its highly efficient cellulolytic activities, T. viride seemed to be responsible for an improved nutrient availability that positively influenced the anaerobic microbiocenosis. Aerobic pre-treatment of organic matter with T. viride is therefore a promising solution to achieve higher methane yields and degradation performances without any additional energy demand, nor undesired by-product inhibition. PMID:26013693

  15. Study of cellulolytic soil fungi and two nova species and new medium

    Institute of Scientific and Technical Information of China (English)

    KHALID Mahmood; YANG Wei-jun; KISHWAR Nazir; RAJPUT Zahid Iqbal; ARIJO Abdullah G.

    2006-01-01

    This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including 2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.

  16. Microbial Consortium with High Cellulolytic Activity (MCHCA for enhanced biogas production.

    Directory of Open Access Journals (Sweden)

    Krzysztof ePoszytek

    2016-03-01

    Full Text Available The use of lignocellulosic biomass as a substrate in agricultural biogas plants is very popular and yields good results. However, the efficiency of anaerobic digestion, and thus biogas production, is not always satisfactory due to the slow or incomplete degradation (hydrolysis of plant matter. To enhance the solubilization of the lignocellulosic biomass various physical, chemical and biological pretreatment methods are used.The aim of this study was to select and characterize cellulose-degrading bacteria, and to construct a microbial consortium, dedicated for degradation of maize silage and enhancing biogas production from this substrate.Over one hundred strains of cellulose-degrading bacteria were isolated from: sewage sludge, hydrolyzer from an agricultural biogas plant, cattle slurry and manure. After physiological characterization of the isolates, sixteen strains (representatives of Bacillus, Providencia and Ochrobactrum genera were chosen for the construction of a Microbial Consortium with High Cellulolytic Activity, called MCHCA. The selected strains had a high endoglucanase activity (exceeding 0.21 IU/mL CMCase activity and a wide range of tolerance to various physical and chemical conditions. Lab-scale simulation of biogas production using the selected strains for degradation of maize silage was carried out in a two-bioreactor system, similar to those used in agricultural biogas plants.The obtained results showed that the constructed MCHCA consortium is capable of efficient hydrolysis of maize silage, and increases biogas production by even 38%, depending on the inoculum used for methane fermentation. The results in this work indicate that the mesophilic Microbial Consortium with High Cellulolytic Activity has a great potential for application on industrial scale in agricultural biogas plants.

  17. Cellulolytic and xylanolytic potential of high β-glucosidase-producing Trichoderma from decaying biomass.

    Science.gov (United States)

    Okeke, Benedict C

    2014-10-01

    Availability, cost, and efficiency of microbial enzymes for lignocellulose bioconversion are central to sustainable biomass ethanol technology. Fungi enriched from decaying biomass and surface soil mixture displayed an array of strong cellulolytic and xylanolytic activities. Strains SG2 and SG4 produced a promising array of cellulolytic and xylanolytic enzymes including β-glucosidase, usually low in cultures of Trichoderma species. Nucleotide sequence analysis of internal transcribed spacer 2 (ITS2) region of rRNA gene revealed that strains SG2 and SG4 are closely related to Trichoderma inhamatum, Trichoderma piluliferum, and Trichoderma aureoviride. Trichoderma sp. SG2 crude culture supernatant correspondingly displayed as much as 9.84 ± 1.12, 48.02 ± 2.53, and 30.10 ± 1.11 units mL(-1) of cellulase, xylanase, and β-glucosidase in 30 min assay. Ten times dilution of culture supernatant of strain SG2 revealed that total activities were about 5.34, 8.45, and 2.05 orders of magnitude higher than observed in crude culture filtrate for cellulase, xylanase, and β-glucosidase, respectively, indicating that more enzymes are present to contact with substrates in biomass saccharification. In parallel experiments, Trichoderma species SG2 and SG4 produced more β-glucosidase than the industrial strain Trichoderma reesei RUT-C30. Results indicate that strains SG2 and SG4 have potential for low cost in-house production of primary lignocellulose-hydrolyzing enzymes for production of biomass saccharides and biofuel in the field.

  18. Genes regulated by AoXlnR, the xylanolytic and cellulolytic transcriptional regulator, in Aspergillus oryzae.

    Science.gov (United States)

    Noguchi, Yuji; Sano, Motoaki; Kanamaru, Kyoko; Ko, Taro; Takeuchi, Michio; Kato, Masashi; Kobayashi, Tetsuo

    2009-11-01

    XlnR is a Zn(II)2Cys6 transcriptional activator of xylanolytic and cellulolytic genes in Aspergillus. Overexpression of the aoxlnR gene in Aspergillus oryzae (A. oryzae xlnR gene) resulted in elevated xylanolytic and cellulolytic activities in the culture supernatant, in which nearly 40 secreted proteins were detected by two-dimensional electrophoresis. DNA microarray analysis to identify the transcriptional targets of AoXlnR led to the identification of 75 genes that showed more than fivefold increase in their expression in the AoXlnR overproducer than in the disruptant. Of these, 32 genes were predicted to encode a glycoside hydrolase, highlighting the biotechnological importance of AoXlnR in biomass degradation. The 75 genes included the genes previously identified as AoXlnR targets (xynF1, xynF3, xynG2, xylA, celA, celB, celC, and celD). Thirty-six genes were predicted to be extracellular, which was consistent with the number of proteins secreted, and 61 genes possessed putative XlnR-binding sites (5'-GGCTAA-3', 5'-GGCTAG-3', and 5'-GGCTGA-3') in their promoter regions. Functional annotation of the genes revealed that AoXlnR regulated the expression of hydrolytic genes for degradation of beta-1,4-xylan, arabinoxylan, cellulose, and xyloglucan and of catabolic genes for the conversion of D-xylose to xylulose-5-phosphate. In addition, genes encoding glucose-6-phosphate 1-dehydrogenase and L-arabinitol-4- dehydrogenase involved in D-glucose and L-arabinose catabolism also appeared to be targets of AoXlnR.

  19. THERMOPHILE ENDOSPORES HAVE RESPONSIVE EXOSPORIUM FOR ATTACHMENT

    Energy Technology Data Exchange (ETDEWEB)

    PANESSA-WARREN,B.; TORTORA,G.T.; WARREN,J.; SABATINI,R.

    1999-08-01

    Recently studies examining the colonization of Clostridial pathogens on agar and human tissue culture cells, demonstrated that (C. sporogenes ATCC 3584, C. difficile ATCC 43594 [patient isolate], C. difficile ATCC 9689 [non-clinical], C. clostridioforme [patient isolate]) bacterial spores (endospores) of the genus Clostridia have an outer membrane that becomes responsive at activation and exhibits extensions of the exosporial membrane that facilitate and maintain spore attachment to a nutritive substrate during germination and initial outgrowth of the newly developed bacterial cell. Therefore this attachment phenomenon plays an important role in insuring bacterial colonization of a surface and the initial stages of the infective process. To see if other non-clinical members of this genus also have this ability to attach to a substrate or food-source during spore germination, and how this attachment process in environmental thermophiles compares to the clinical paradigm (in relation to time sequence, exosporial membrane structure, type of attachment structures, composition of the membrane etc...), sediment samples were collected in sterile transport containers at 4 geothermal sites at Yellowstone National Park in Wyoming. Because spore forming bacteria will produce spores when conditions are unfavorable for growth, the samples were sealed and stored at 4 C. After 8 months the samples were screened for the presence of spores by light microscope examination using malachite green/safranin, and traditional endospores were identified in significant quantities from the Terrace Spring site (a 46 C lake with bacterial mats and a rapidly moving run-off channel leading to a traditional hot spring). The highest spore population was found in the top sediment and benthic water of the run-off channel, pH 8.1.

  20. [Biodegradation of organic pollutants by thermophiles and their applications: a review].

    Science.gov (United States)

    Cui, Jing-Lan; Chen, Chen; Qin, Zhi-Hui; Yu, Chun-Na; Shen, Hui; Shen, Chao-Feng; Chen, Ying-Xu

    2012-11-01

    Persistent organic pollutants have increasingly become a critical environmental concern, while thermophiles have the high potential of degrading various kinds of environmental organic pollutants. At high temperatures, thermophiles have higher metabolic activity, and the competition by mesophiles is reduced, meanwhile, the solubility and bioavailability of some persistent organic pollutants are greatly increased, and thus, the degradation of the pollutants by thermophiles is more rapid and complete. Therefore, thermophils are of great significance for the bio-treatment of organic wastewater and the bioremediation of organic pollutants-contaminated sites. This paper introduced the research progress on the degradation of organic pollutants by thermophiles in terms of the characteristics of thermophiles in degrading organic pollutants, the effects of temperature on the degradation, the degradation pathways, the degradation enzymes, their coding genes, and practical engineering applications. The future research directions including the degradation mechanisms of thermophiles, their resources reserve, related technology strategies and their applications were also prospected. PMID:23431811

  1. Design of A solar Thermophilic Anaerobic Reactor for Small Farms

    NARCIS (Netherlands)

    Mashad, El H.; Loon, van W.K.P.; Zeeman, G.; Bot, G.P.A.; Lettinga, G.

    2004-01-01

    A 10 m(3) completely stirred tank reactor has been designed for anaerobic treatment of liquid cow manure under thermophilic conditions (50degreesC), using a solar heating system mounted on the reactor roof. Simulation models for two systems have been developed. The first system consists of loose com

  2. Abiotic and microbiotic factors controlling biofilm formation by thermophilic sporeformers

    NARCIS (Netherlands)

    Zhao, Y.; Caspers, M.P.M.; Metselaar, K.I.; Boer, de P.; Roeselers, G.; Moezelaar, R.; Nierop Groot, M.N.; Montijn, R.C.; Abee, T.; Kort, R.

    2013-01-01

    One of the major concerns in the production of dairy concentrates is the risk of contamination by heat-resistant spores from thermophilic bacteria. In order to acquire more insight in the composition of microbial communities occurring in the dairy concentrate industry, a bar-coded 16S amplicon seque

  3. Abiotic and Microbiotic Factors Controlling Biofilm Formation by Thermophilic Sporeformers

    NARCIS (Netherlands)

    Zhao, Y.; Caspers, M.P.M.; Metselaar, K.I.; Boer, P. de; Roeselers, G.; Moezelaar, R.; Groot, M.N.; Montijn, R.C.; Abee, T.; Korta, R.

    2013-01-01

    One of the major concerns in the production of dairy concentrates is the risk of contamination by heat-resistant spores from thermophilic bacteria. In order to acquire more insight in the composition of microbial communities occurring in the dairy concentrate industry, a bar-coded 16S amplicon seque

  4. Diversity and ecophysiological features of thermophilic carboxydotrophic anaerobes

    NARCIS (Netherlands)

    Sokolova, T.G.; Henstra, A.M.; Sipma, J.; Parshina, S.N.; Stams, A.J.M.; Lebedinsky, A.V.

    2009-01-01

    Both natural and anthropogenic hot environments contain appreciable levels of carbon monoxide (CO). Anaerobic microbial communities play an important role in CO conversion in such environments. CO is involved in a number of redox reactions. It is biotransformed by thermophilic methanogens, acetogens

  5. Hydrophobic and Electrostatic Cell Surface Properties of Thermophilic Dairy Streptococci

    NARCIS (Netherlands)

    Van der Mei, HC; de Vries, Jacob; Busscher, HJ

    1993-01-01

    Microbial adhesion to hydrocarbons (MATH) and microelectrophoresis were done in 10 mM potassium phosphate solutions to characterize the surfaces of thermophilic dairy streptococci, isolated from pasteurizers. Regardless of whether they were grown (in M17 broth) with lactose, sucrose, or glucose adde

  6. Kinetic comparisons of mesophilic and thermophilic aerobic biomass

    NARCIS (Netherlands)

    Vogelaar, J.C.T.; Klapwijk, A.; Temmink, H.; Lier, van J.B.

    2003-01-01

    Kinetic parameters describing growth and decay of mesophilic (30degreesC) and thermophilic (55degreesC) aerobic biomass were determined in continuous and batch experiments by using oxygen uptake rate measurements
    Kinetic parameters describing growth and decay of mesophilic (30degreesC) and therm

  7. Thermophilic aerobic post treatment of anaerobically pretreated paper process water

    NARCIS (Netherlands)

    Vogelaar, J.C.T.

    2002-01-01

    Thermophilic waste- or process water treatment increases in importance as industries shift from end-of-pipe treatment towards integrated process water treatment. The need for process water treatment becomes evident as the levels of pollutants in industrial water circuits need to be co

  8. Effect of cobalt on the Anaerobic Thermophilic Conversion of Methanol

    NARCIS (Netherlands)

    Paulo, P.L.; Jiang, B.; Cysneiros, D.; Stams, A.J.M.

    2004-01-01

    The importance of cobalt on the anaerobic conversion of methanol under thermophilic conditions was studied in three parallel lab-scale UASB-reactors and in cobalt-limited enriched cultures. Reactors R1, R2, and R3 were fed with methanol in a bicarbonate-buffered medium, supplied with iron and macron

  9. Evolution of High Cellulolytic Activity in Symbiotic Streptomyces through Selection of Expanded Gene Content and Coordinated Gene Expression.

    Science.gov (United States)

    Book, Adam J; Lewin, Gina R; McDonald, Bradon R; Takasuka, Taichi E; Wendt-Pienkowski, Evelyn; Doering, Drew T; Suh, Steven; Raffa, Kenneth F; Fox, Brian G; Currie, Cameron R

    2016-06-01

    The evolution of cellulose degradation was a defining event in the history of life. Without efficient decomposition and recycling, dead plant biomass would quickly accumulate and become inaccessible to terrestrial food webs and the global carbon cycle. On land, the primary drivers of plant biomass deconstruction are fungi and bacteria in the soil or associated with herbivorous eukaryotes. While the ecological importance of plant-decomposing microbes is well established, little is known about the distribution or evolution of cellulolytic activity in any bacterial genus. Here we show that in Streptomyces, a genus of Actinobacteria abundant in soil and symbiotic niches, the ability to rapidly degrade cellulose is largely restricted to two clades of host-associated strains and is not a conserved characteristic of the Streptomyces genus or host-associated strains. Our comparative genomics identify that while plant biomass degrading genes (CAZy) are widespread in Streptomyces, key enzyme families are enriched in highly cellulolytic strains. Transcriptomic analyses demonstrate that cellulolytic strains express a suite of multi-domain CAZy enzymes that are coregulated by the CebR transcriptional regulator. Using targeted gene deletions, we verify the importance of a highly expressed cellulase (GH6 family cellobiohydrolase) and the CebR transcriptional repressor to the cellulolytic phenotype. Evolutionary analyses identify complex genomic modifications that drive plant biomass deconstruction in Streptomyces, including acquisition and selective retention of CAZy genes and transcriptional regulators. Our results suggest that host-associated niches have selected some symbiotic Streptomyces for increased cellulose degrading activity and that symbiotic bacteria are a rich biochemical and enzymatic resource for biotechnology. PMID:27276034

  10. Selection and molecular characterization of cellulolytic-xylanolytic fungi from surface soil-biomass mixtures from Black Belt sites.

    Science.gov (United States)

    Okeke, Benedict C; Hall, Rosine W; Nanjundaswamy, Ananda; Thomson, M Sue; Deravi, Yasaman; Sawyer, Leah; Prescott, Andrew

    2015-06-01

    Plant biomass is an abundant renewable natural resource that can be transformed into chemical feedstocks. Enzymes used in saccharification of lignocellulosic biomass are a major part of biofuel production costs. A cocktail of cellulolytic and xylanolytic enzymes are required for optimal saccharification of biomass. Accordingly, thirty-two fungal pure cultures were obtained from surface soil-biomass mixtures collected from Black Belt sites in Alabama by culturing on lignocellulosic biomass medium. The fungal strains were screened for the coproduction of cellulolytic and xylanolytic enzymes. Strains that displayed promising levels of cellulolytic and xylanolytic enzymes were characterized by molecular analysis of DNA sequences from the large subunit and internal transcribed spacer (ITS) of their ribosomal RNA gene. Nucleotide sequence analysis revealed that two most promising isolates FS22A and FS5A were most similar to Penicillium janthinellum and Trichoderma virens. Production dynamics of cellulolytic and xylanolytic enzymes from these two strains were explored in submerged fermentation. Volumetric productivity after 120 h incubation was 121.08 units/L/h and 348 units/L/h for the filter paper cellulase and xylanase of strain FS22A, and 90.83 units/L/h and 359 units/L/h, respectively for strain FS5A. Assays with 10 times dilution of enzymes revealed that the activities were much higher than that observed in the crude culture supernatant. Additionally, both FS22A and FS5A also produced amylase in lignocellulose medium. The enzyme profiles of these strains and their activities suggest potential applications in cost effective biomass conversion and biodegradation. PMID:25817459

  11. Evolution of High Cellulolytic Activity in Symbiotic Streptomyces through Selection of Expanded Gene Content and Coordinated Gene Expression.

    Science.gov (United States)

    Book, Adam J; Lewin, Gina R; McDonald, Bradon R; Takasuka, Taichi E; Wendt-Pienkowski, Evelyn; Doering, Drew T; Suh, Steven; Raffa, Kenneth F; Fox, Brian G; Currie, Cameron R

    2016-06-01

    The evolution of cellulose degradation was a defining event in the history of life. Without efficient decomposition and recycling, dead plant biomass would quickly accumulate and become inaccessible to terrestrial food webs and the global carbon cycle. On land, the primary drivers of plant biomass deconstruction are fungi and bacteria in the soil or associated with herbivorous eukaryotes. While the ecological importance of plant-decomposing microbes is well established, little is known about the distribution or evolution of cellulolytic activity in any bacterial genus. Here we show that in Streptomyces, a genus of Actinobacteria abundant in soil and symbiotic niches, the ability to rapidly degrade cellulose is largely restricted to two clades of host-associated strains and is not a conserved characteristic of the Streptomyces genus or host-associated strains. Our comparative genomics identify that while plant biomass degrading genes (CAZy) are widespread in Streptomyces, key enzyme families are enriched in highly cellulolytic strains. Transcriptomic analyses demonstrate that cellulolytic strains express a suite of multi-domain CAZy enzymes that are coregulated by the CebR transcriptional regulator. Using targeted gene deletions, we verify the importance of a highly expressed cellulase (GH6 family cellobiohydrolase) and the CebR transcriptional repressor to the cellulolytic phenotype. Evolutionary analyses identify complex genomic modifications that drive plant biomass deconstruction in Streptomyces, including acquisition and selective retention of CAZy genes and transcriptional regulators. Our results suggest that host-associated niches have selected some symbiotic Streptomyces for increased cellulose degrading activity and that symbiotic bacteria are a rich biochemical and enzymatic resource for biotechnology.

  12. Evolution of High Cellulolytic Activity in Symbiotic Streptomyces through Selection of Expanded Gene Content and Coordinated Gene Expression.

    Directory of Open Access Journals (Sweden)

    Adam J Book

    2016-06-01

    Full Text Available The evolution of cellulose degradation was a defining event in the history of life. Without efficient decomposition and recycling, dead plant biomass would quickly accumulate and become inaccessible to terrestrial food webs and the global carbon cycle. On land, the primary drivers of plant biomass deconstruction are fungi and bacteria in the soil or associated with herbivorous eukaryotes. While the ecological importance of plant-decomposing microbes is well established, little is known about the distribution or evolution of cellulolytic activity in any bacterial genus. Here we show that in Streptomyces, a genus of Actinobacteria abundant in soil and symbiotic niches, the ability to rapidly degrade cellulose is largely restricted to two clades of host-associated strains and is not a conserved characteristic of the Streptomyces genus or host-associated strains. Our comparative genomics identify that while plant biomass degrading genes (CAZy are widespread in Streptomyces, key enzyme families are enriched in highly cellulolytic strains. Transcriptomic analyses demonstrate that cellulolytic strains express a suite of multi-domain CAZy enzymes that are coregulated by the CebR transcriptional regulator. Using targeted gene deletions, we verify the importance of a highly expressed cellulase (GH6 family cellobiohydrolase and the CebR transcriptional repressor to the cellulolytic phenotype. Evolutionary analyses identify complex genomic modifications that drive plant biomass deconstruction in Streptomyces, including acquisition and selective retention of CAZy genes and transcriptional regulators. Our results suggest that host-associated niches have selected some symbiotic Streptomyces for increased cellulose degrading activity and that symbiotic bacteria are a rich biochemical and enzymatic resource for biotechnology.

  13. Survival of thermophilic and hyper-thermophilic microorganisms after exposure to UV-C, ionizing radiation and desiccation

    International Nuclear Information System (INIS)

    In this study, we investigated the ability of several (hyper-) thermophilic Archaea and phylo-genetically deep-branching thermophilic Bacteria to survive high fluences of monochromatic UV-C (254 nm) and high doses of ionizing radiation, respectively. Nine out of fourteen tested microorganisms showed a surprisingly high tolerance against ionizing radiation, and two species (Aquifex pyrophilus and Ignicoccus hospitalis) were even able to survive 20 kGy. Therefore, these species had a comparable survivability after exposure to ionizing radiation such as Deinococcus radiodurans. In contrast, there was nearly no difference in survival of the tested strains after exposure to UV-C under anoxic conditions. If the cells had been dried in advance of UV-C irradiation, they were more sensitive to UV-C radiation compared with cells irradiated in liquid suspension; this effect could be reversed by the addition of protective material like sulfidic ores before irradiation. By exposure to UV-C, photoproducts were formed in the DNA of irradiated Archaea and Bacteria. The distribution of the main photoproducts was species specific, but the amount of the photoproducts was only partly dependent on the applied fluence. Overall, our results show that tolerance to radiation seems to be a common phenomenon among thermophilic and hyper-thermophilic microorganisms. (authors)

  14. Thermophilic hydrogen production from sludge pretreated by thermophilic bacteria: analysis of the advantages of microbial community and metabolism.

    Science.gov (United States)

    Zheng, He-Shan; Guo, Wan-Qian; Yang, Shan-Shan; Feng, Xiao-Chi; Du, Juan-Shan; Zhou, Xian-Jiao; Chang, Jo-Shu; Ren, Nan-Qi

    2014-11-01

    In this study, the effects of thermophilic bacteria pretreatment and elevated fermentation temperature on hydrogen production from sludge were examined. The highest hydrogen yield of 19.9mlH2g(-1) VSS was achieved at 55°C by using pretreated sludge, which was 48.6% higher than raw sludge without pretreatment, and 28.39% higher than when fermented at 35°C. To explore the internal factors of this superior hydrogen production performance, the microbial community and the metabolism analysis were performed by using high-throughput sequencing and excitation-emission matrix. The pretreated sludge showed better utilization of dissolved organic matter and less inhibition of metabolism, especially at thermophilic condition. The 454 sequencing data indicated that microbial abundance was distinctly reduced and extremely high proportion of hydrogen-producing bacteria was found in the thermophilic community (Thermoanaerobacterium accounted for 93.75%). Thus, the pretreated sludge and thermophilic condition showed significant advantages in the hydrogen production using waste sludge as substrate.

  15. Thermophilic (55 - 65°C) and extreme thermophilic (70 - 80°C) sulfate reduction in methanol and formate-fed UASB reactors

    NARCIS (Netherlands)

    Vallero, M.V.G.; Camarero, E.; Lettinga, G.; Lens, P.N.L.

    2004-01-01

    The feasibility of thermophilic (55-65 degreesC) and extreme thermophilic (70-80 degreesC) sulfate-reducing processes was investigated in three lab-scale upflow anaerobic sludge bed (UASB) reactors fed with either methanol or formate as the sole substrates and inoculated with mesophilic granular slu

  16. Performance and microbial community analysis of two-stage process with extreme thermophilic hydrogen and thermophilic methane production from hydrolysate in UASB reactors

    DEFF Research Database (Denmark)

    Kongjan, Prawit; O-Thong, Sompong; Angelidaki, Irini

    2011-01-01

    The two-stage process for extreme thermophilic hydrogen and thermophilic methane production from wheat straw hydrolysate was investigated in up-flow anaerobic sludge bed (UASB) reactors. Specific hydrogen and methane yields of 89ml-H2/g-VS (190ml-H2/g-sugars) and 307ml-CH4/g-VS, respectively were...

  17. Cellulosic Ethanol Production by Recombinant Cellulolytic Bacteria Harbouring pdc and adh II Genes of Zymomonas mobilis.

    Science.gov (United States)

    Piriya, P Sobana; Vasan, P Thirumalai; Padma, V S; Vidhyadevi, U; Archana, K; Vennison, S John

    2012-01-01

    The ethanol fermenting genes such as pyruvate decarboxylase (pdc) and alcohol dehydrogenase II (adh II) were cloned from Zymomonas mobilis and transformed into three different cellulolytic bacteria, namely Enterobacter cloacae JV, Proteus mirabilis JV and Erwinia chrysanthemi and their cellulosic ethanol production capability was studied. Recombinant E. cloacae JV was found to produce 4.5% and 3.5% (v/v) ethanol, respectively, when CMC and 4% NaOH pretreated bagasse were used as substrates, whereas recombinant P. mirabilis and E. chrysanthemi with the same substrates could only produce 4%, 3.5%, 1%, and 1.5 % of ethanol, respectively. The recombinant E. cloacae strain produced twofold higher percentage of ethanol than the wild type. The recombinant E. cloacae strain could be improved further by increasing its ethanol tolerance capability through media optimization and also by combining multigene cellulase expression for enhancing ethanol production from various types of lignocellulosic biomass so that it can be used for industrial level ethanol production.

  18. Streptomyces abietis sp. nov., a cellulolytic bacterium isolated from soil of a pine forest.

    Science.gov (United States)

    Fujii, Katsuhiko; Satomi, Masataka; Fukui, Youhei; Matsunobu, Shun; Morifuku, Youji; Enokida, Yuya

    2013-12-01

    Cellulolytic bacteria A191(T), A192 and A193 isolated from the soil of Sakhalin fir forest in Hokkaido, Japan were studied phenotypically, genotypically and phylogenetically. Analysis of their 16S rRNA gene and gyrB sequences and DNA base composition suggested that these isolates were conspecific and members of the genus Streptomyces. However, levels of 16S rRNA gene and gyrB sequence similarity between the isolates and the type strains of their closest relatives in the genus Streptomyces were no higher than 97.9 and 95.0 %, respectively, implying that these isolates were distinctive. Moreover, the results of DNA-DNA hybridization experiments and physiological characterization clearly differentiated these isolates from their closest neighbours. It is therefore concluded that these isolates represent a novel species of the genus Streptomyces, for which the name Streptomyces abietis is proposed. The type strain is A191(T) ( = NBRC 109094(T) = DSM 42080(T)). PMID:23990653

  19. Cellulosic Ethanol Production by Recombinant Cellulolytic Bacteria Harbouring pdc and adh II Genes of Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    P. Sobana Piriya

    2012-01-01

    Full Text Available The ethanol fermenting genes such as pyruvate decarboxylase (pdc and alcohol dehydrogenase II (adh II were cloned from Zymomonas mobilis and transformed into three different cellulolytic bacteria, namely Enterobacter cloacae JV, Proteus mirabilis JV and Erwinia chrysanthemi and their cellulosic ethanol production capability was studied. Recombinant E. cloacae JV was found to produce 4.5% and 3.5% (v/v ethanol, respectively, when CMC and 4% NaOH pretreated bagasse were used as substrates, whereas recombinant P. mirabilis and E. chrysanthemi with the same substrates could only produce 4%, 3.5%, 1%, and 1.5 % of ethanol, respectively. The recombinant E. cloacae strain produced twofold higher percentage of ethanol than the wild type. The recombinant E. cloacae strain could be improved further by increasing its ethanol tolerance capability through media optimization and also by combining multigene cellulase expression for enhancing ethanol production from various types of lignocellulosic biomass so that it can be used for industrial level ethanol production.

  20. Thermophile-specific proteins: the gene product of aq_1292 from Aquifex aeolicus is an NTPase

    OpenAIRE

    Klinger, Claudia; Roßbach, Michael; Howe, Rebecca; Kaufmann, Michael

    2003-01-01

    Background To identify thermophile-specific proteins, we performed phylogenetic patterns searches of 66 completely sequenced microbial genomes. This analysis revealed a cluster of orthologous groups (COG1618) which contains a protein from every thermophile and no sequence from 52 out of 53 mesophilic genomes. Thus, COG1618 proteins belong to the group of thermophile-specific proteins (THEPs) and therefore we here designate COG1618 proteins as THEP1s. Since no THEP1 had been analyzed biochemic...

  1. Isolation of anaerobic bacterial strains from cellulolytic bacterial com- munity WSC-9%纤维素分解复合菌系WSC-9中厌氧细菌的分离

    Institute of Scientific and Technical Information of China (English)

    温雪; 付博锐; 王彦杰; 高亚梅; 刘权; 晏磊; 王伟东

    2013-01-01

    The microbial community WSC-9 capable of degrading lignocellulose with high efficiency was enriched from composting of cattle manure and rice straw. The aims of this study were to isolate and identify the anaerobic bacterial strains from the cellulose-degrading bacterial community. An anaerobic, thermophilic and cellulolytic bacterium was isolated, which was named WSC-9-7. More than 47% of rice straw was degraded within 10 days of inoculation at 50 ° C by WSC-9-7. WSC-9-7 is a spore-forming and straight rod. Cellobiose, cellulose, filter paper and rice straw can be utilized as sole carbon and energy sources by WSC-9-7 in medium. On the basis of 16S rDNA gene sequence similarity, WSC-9-7 was mapped to the genus Clostridium. It is closely related to HAW-RM37-2-B-1600d-W (99%), and Clostridium islandicum AK1(98%). Clostridium islandicum AK1 was a new anaerobic, saccharolytic, thermophilic bacterium, isolated from hot spring in Iceland. HAW-RM37-2-B-1600d-W was uncultured clone from compost environmental samples. All of them were thermophilic and anaerobic bacterium. Hence, WSC-9-7 represents a novel species is proposed.%  复合菌系WSC-9是一组具高效稳定分解纤维素能力的细菌复合群体.为了研究其微生物组成,以纤维素分解情况为依据,分离复合菌系中具有纤维素分解能力的厌氧纯培养菌株,通过16S rDNA基因序列初步分析确定系统发育地位.从WSC-9中获得1株可有效降解纤维素的严格厌氧细菌WSC-9-7,50℃培养10 d,稻秆的总干重减少了47%.WSC-9-7为杆菌,产孢,能够利用纤维二糖、纤维素、滤纸、稻秆等.经数据库比对,与菌株HAW-RM37-2-B-1600d-W(FN563295)的相似性达到99%,与Clostridium islandicum AK1(EF088328)的相似性为98%.其中,Clostridium islandicum AK1厌氧且可以分解多糖类物质,获于冰岛的热泉;HAW-RM37-2-B-1600d-W在堆肥样品的克隆结果中获得,未获得纯培养.菌株WSC-9-7与这两株细菌均为嗜高温的严格

  2. Proteomic analysis of acetylation in thermophilic Geobacillus kaustophilus.

    Science.gov (United States)

    Lee, Dong-Woo; Kim, Dooil; Lee, Yong-Jik; Kim, Jung-Ae; Choi, Ji Young; Kang, Sunghyun; Pan, Jae-Gu

    2013-08-01

    Recent analysis of prokaryotic N(ε)-lysine-acetylated proteins highlights the posttranslational regulation of a broad spectrum of cellular proteins. However, the exact role of acetylation remains unclear due to a lack of acetylated proteome data in prokaryotes. Here, we present the N(ε)-lysine-acetylated proteome of gram-positive thermophilic Geobacillus kaustophilus. Affinity enrichment using acetyl-lysine-specific antibodies followed by LC-MS/MS analysis revealed 253 acetylated peptides representing 114 proteins. These acetylated proteins include not only common orthologs from mesophilic Bacillus counterparts, but also unique G. kaustophilus proteins, indicating that lysine acetylation is pronounced in thermophilic bacteria. These data complement current knowledge of the bacterial acetylproteome and provide an expanded platform for better understanding of the function of acetylation in cellular metabolism.

  3. Startup and stability of thermophilic anaerobic digestion of OFMSW

    KAUST Repository

    El-Fadel, Mutasem E.

    2013-01-01

    Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is promoted as an energy source and more recently as a greenhouse gas (GHG) mitigation measure. In this context, AD systems operating at thermophilic temperatures (55-60°C)-compared to mesophilic temperatures (35-40°C)-have the unique feature of producing hygienic soil conditioners with greater process efficiency, higher energy yield, and more GHG savings. Startup of AD systems is often constrained by the lack of acclimated seeds, leading to process instability and failure. The authors focus on strategies to startup thermophilic digesters treating OFMSW in the absence of acclimated seeds and examines constraints associated with process stability and ways to overcome them. Relevant gaps in the literature and future research needs are delineated. © 2013 Taylor & Francis Group, LLC.

  4. Bioleaching of multiple metals from contaminated sediment by moderate thermophiles.

    Science.gov (United States)

    Gan, Min; Jie, Shiqi; Li, Mingming; Zhu, Jianyu; Liu, Xinxing

    2015-08-15

    A moderately thermophilic consortium was applied in bioleaching multiple metals from contaminated sediment. The consortium got higher acidification and metals soubilization efficiency than that of the pure strains. The synergistic effect of the thermophilic consortium accelerated substrates utilization. The utilization of substrate started with sulfur in the early stage, and then the pH declined, giving rise to making use of the pyrite. Community dynamic showed that A. caldus was the predominant bacteria during the whole bioleaching process while the abundance of S. thermotolerans increased together with pyrite utilization. Solubilization efficiency of Zn, Cu, Mn and Cd reached 98%, 94%, 95%, and 89% respectively, while As, Hg, Pb was only 45%, 34%, 22%. Logistic model was used to simulate the bioleaching process, whose fitting degree was higher than 90%. Correlation analysis revealed that metal leaching was mainly an acid solubilization process. Fraction analysis revealed that metals decreased in mobility and bioavailability. PMID:26140749

  5. Widespread Disulfide Bonding in Proteins from Thermophilic Archaea

    Directory of Open Access Journals (Sweden)

    Julien Jorda

    2011-01-01

    Full Text Available Disulfide bonds are generally not used to stabilize proteins in the cytosolic compartments of bacteria or eukaryotic cells, owing to the chemically reducing nature of those environments. In contrast, certain thermophilic archaea use disulfide bonding as a major mechanism for protein stabilization. Here, we provide a current survey of completely sequenced genomes, applying computational methods to estimate the use of disulfide bonding across the Archaea. Microbes belonging to the Crenarchaeal branch, which are essentially all hyperthermophilic, are universally rich in disulfide bonding while lesser degrees of disulfide bonding are found among the thermophilic Euryarchaea, excluding those that are methanogenic. The results help clarify which parts of the archaeal lineage are likely to yield more examples and additional specific data on protein disulfide bonding, as increasing genomic sequencing efforts are brought to bear.

  6. Use of bacteriophage for the selective isolation of thermophilic actinomycetes from composted eucalyptus bark.

    Science.gov (United States)

    Kurtböke, D I; Murphy, N E; Sivasithamparam, K

    1993-01-01

    A method was developed to reduce the numbers of thermophilic bacteria on isolation plates, which in turn facilitated the detection and isolation of thermophilic actinomycetes. The method involves exposing the test material to bacteriophage suspensions prior to inoculation on isolation plates. This method was applied to composted eucalyptus bark samples, which were then inoculated on R8 and 1/2 TSA + 0.2% casein hydrolysate agar plates. The phage susceptibility of thermophilic bacteria provided a selective means of reducing their numbers on isolation plates and hence increased the numbers of Thermomonospora, Saccharopolyspora rectivirgula, and thermophilic Streptomyces spp. on these media in comparison with the numbers recorded from control plates.

  7. State of the art and future perspectives of thermophilic anaerobic digestion

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær; Mladenovska, Zuzana; Iranpour, R.;

    2002-01-01

    The slate of the art of thermophilic digestion is discussed. Thermophilic digestion is a well established technology in Europe for treatment of mixtures of waste in common large scale biogas plants or for treatment of the organic fraction of municipal solid waste. Due to a large number of failures......-up strategy based on the actual activity of key microbes can be used to ensure proper and fast transfer of mesophilic digesters into thermophilic operation. Extreme thermophilic temperatures of 65degreesC or more may be necessary in the future to meet the demands for full sanitation of the waste material...

  8. Solar Thermophilic Anaerobic Reactor (STAR) for Renewable Energy Production

    OpenAIRE

    Mashad, El, H.

    2003-01-01

    Liquid and solid cattle manures are major waste streams inEgypt. The main objective of this research was maximising the net energy production from these wastes by using a solar energy heating system. High concentration of ammonia can strongly affect the gross methane production via inhibition of methanogenesis and reduced hydrolysis. The latter is only limited addressed so far in literature and therefore taken as a second objective of this study.To be able to design a solar thermophilic anaer...

  9. Thermophilic biological nitrogen removal in industrial wastewater treatment.

    OpenAIRE

    Lopez-Vazquez, CM; Kubare, M.; Saroj, DP; Chikamba, C; Schwarz, J.; Daims, H.; Brdjanovic, D.

    2013-01-01

    Nitrification is an integral part of biological nitrogen removal processes and usually the limiting step in wastewater treatment systems. Since nitrification is often considered not feasible at temperatures higher than 40 °C, warm industrial effluents (with operating temperatures higher than 40 °C) need to be cooled down prior to biological treatment, which increases the energy and operating costs of the plants for cooling purposes. This study describes the occurrence of thermophilic biologic...

  10. Sulfur Reduction by the Extremely Thermophilic Archaebacterium Pyrodictium occultum

    OpenAIRE

    Parameswaran, A. K.; Provan, C. N.; Sturm, F. J.; Kelly, R.M.

    1987-01-01

    The relationship between growth and biological sulfur reduction for the extremely thermophilic archaebacterium Pyrodictium occultum was studied over a temperature range of 98 to 105°C. The addition of yeast extract (0.2 g/liter) to the medium was found to increase hydrogen sulfide production significantly, especially at higher temperatures. Sulfide production in uninoculated controls with and without yeast extract was noticeable but substantially below the levels observed in samples containin...

  11. Vertical zonation and seed germination indices of chromium resistant cellulolytic and nitrogen fixing bacteria from a chronically metal exposed land area

    International Nuclear Information System (INIS)

    Twenty eight cellulolytic and 25 nitrogen fixing bacteria were isolated from 20, 40 and 60 cm depths of the chromium contaminated land area. The cellulolytic as well as nitrogen fixing microbial communities in soil profiles were dominated by genus Bacillus. More diverse nitrogen fixing bacterial isolates belonging to different genera Paenibacillus, Corynebacterium and Pseudomonas were observed as compared to cellulolytic bacterial community. Majority of the cellulolytic bacteria were found inhabitants of 20 cm soil layer while 40 cm depth was the preferred zone for the nitrogen fixing bacteria. Screening of the bacterial isolates for chromium resistance showed that isolates designated as ASK15 and ASK16 were able to resist up to 1800 mg/l of chromium while the nitrogen fixing isolates which offered a maximum resistant level up to 1650 mg/l of chromium were ASNt10 and ASNS13. Nitrogen fixing isolates enhanced seed germination by 33% and expressed efficient nitrogenase activity up to 0.80 (C/sub 2/H/sub 2/ nmol/ml/hr). Growth promoting assay proved ASNt10 a potential isolate which produced 90 meu g/ml of indoleacetic acid (IAA). Though cellulolytic isolates did not affect seed germination, a significant influence on root length similar to that of ASNt10 and ASNS13 with nearly 5-fold increase in comparison with uninoculated control was observed. The isolates ASK15, ASK16 were identified as Bacillus cereus while ASNt10 and ASNS13 as Paenibacillus barcinonensis and Bacillus megaterium, respectively. (author)

  12. Purification and characterization of a type B feruloyl esterase (StFAE-A) from the thermophilic fungus Sporotrichum thermophile

    DEFF Research Database (Denmark)

    Topakas, E.; Stamatis, H.; Biely, P.;

    2004-01-01

    . thermophile (a maximum of 34% total ferulic acid released after 1 h incubation). StFAE-A by itself could release FA, but at a level almost 47-fold lower than that obtained in the presence of xylanase. The potential of StFAE-A for the synthesis of various phenolic acid esters was tested using a ternary water......-organic mixture consisting of n-hexane, 1-butanol and water as a reaction system....

  13. Hemicellulases from the ethanologenic thermophile Thermoanaerobacter ethanolicus and related anaerobic thermophiles. Final report, September 1992--June 1996

    Energy Technology Data Exchange (ETDEWEB)

    Wiegel, J.

    1998-05-01

    The SHORT TERM GOALS of this application were to characterize hemicellulases from anaerobic thermophiles on the biochemical and molecular level to extend the presently limited knowledge of hemicellulases in anaerobic thermophilic bacteria. This objective includes the following TASKS: (1) Traditional purification and biochemical/biophysical characterization of xylanases from the newly isolated, slightly alkalitolerant strain NDF190, and the slightly acid-tolerant strain YS485, both with high xylanolytic activities, and of the 4-0-methyl glucuronidase and arabinosidase from strain NDF190 and the acetyl (xylan) esterase from T. ethanolicus. This also includes determining the N-terminal sequences and obtaining gene probes. (2) Elucidation of the regulation of hemicellulolytic enzymes in anaerobic thermophiles. (3) To clone into E. coli and identify the multiplicity of the enzymes involved in hemicellulose degradation by T. ethanolicus and other suitable organisms. (4) To purify and characterize the recombinant enzymes with the goal of identifying the best enzymes for cloning into the ethanologenic T. ethanolicus to obtain an optimized hemicellulose utilization by this bacterium (one of our long term goals).

  14. Hemicellulases from the ethanologenic thermophile, Thermoanaerobacter ethanolicus and related anaerobic thermophiles. Final report, September 1992--June 1996

    Energy Technology Data Exchange (ETDEWEB)

    Wiegel, J.

    1998-09-01

    The short term goals of this application were to characterize hemicellulases from anaerobic thermophiles on the biochemical and molecular level to extend the presently limited knowledge of hemicellulases in anaerobic thermophilic bacteria. This objective includes the following tasks: (1) Traditional purification and biochemical/biophysical characterization of xylanases from the newly isolated, slightly alkalitolerant strain NDF190, and the slightly acid-tolerant strain YS485, both with high xylanolytic activities, and of the 4-O-methyl glucuronidase and arabinosidase from strain NDF190 and the acetyl (xylan) esterase from T. ethanolicus. This also includes determining the N-terminal sequences and obtaining gene probes. (2) Elucidation of the regulation of hemicellulolytic enzymes in anaerobic thermophiles. (3) To clone into E. coli and identify the multiplicity of the enzymes involved in hemicellulose degradation by T. ethanolicus and other suitable organisms. (4) To purify and characterize the recombinant enzymes with the goal of identifying the best enzymes for cloning into the ethanologenic T. ethanolicus to obtain an optimized hemicellulose utilization by this bacterium.

  15. Microbial Consortium with High Cellulolytic Activity (MCHCA) for Enhanced Biogas Production.

    Science.gov (United States)

    Poszytek, Krzysztof; Ciezkowska, Martyna; Sklodowska, Aleksandra; Drewniak, Lukasz

    2016-01-01

    The use of lignocellulosic biomass as a substrate in agricultural biogas plants is very popular and yields good results. However, the efficiency of anaerobic digestion, and thus biogas production, is not always satisfactory due to the slow or incomplete degradation (hydrolysis) of plant matter. To enhance the solubilization of the lignocellulosic biomass various physical, chemical and biological pretreatment methods are used. The aim of this study was to select and characterize cellulose-degrading bacteria, and to construct a microbial consortium, dedicated for degradation of maize silage and enhancing biogas production from this substrate. Over 100 strains of cellulose-degrading bacteria were isolated from: sewage sludge, hydrolyzer from an agricultural biogas plant, cattle slurry and manure. After physiological characterization of the isolates, 16 strains (representatives of Bacillus, Providencia, and Ochrobactrum genera) were chosen for the construction of a Microbial Consortium with High Cellulolytic Activity, called MCHCA. The selected strains had a high endoglucanase activity (exceeding 0.21 IU/mL CMCase activity) and a wide range of tolerance to various physical and chemical conditions. Lab-scale simulation of biogas production using the selected strains for degradation of maize silage was carried out in a two-bioreactor system, similar to those used in agricultural biogas plants. The obtained results showed that the constructed MCHCA consortium is capable of efficient hydrolysis of maize silage, and increases biogas production by even 38%, depending on the inoculum used for methane fermentation. The results in this work indicate that the mesophilic MCHCA has a great potential for application on industrial scale in agricultural biogas plants.

  16. Microbial Consortium with High Cellulolytic Activity (MCHCA) for Enhanced Biogas Production.

    Science.gov (United States)

    Poszytek, Krzysztof; Ciezkowska, Martyna; Sklodowska, Aleksandra; Drewniak, Lukasz

    2016-01-01

    The use of lignocellulosic biomass as a substrate in agricultural biogas plants is very popular and yields good results. However, the efficiency of anaerobic digestion, and thus biogas production, is not always satisfactory due to the slow or incomplete degradation (hydrolysis) of plant matter. To enhance the solubilization of the lignocellulosic biomass various physical, chemical and biological pretreatment methods are used. The aim of this study was to select and characterize cellulose-degrading bacteria, and to construct a microbial consortium, dedicated for degradation of maize silage and enhancing biogas production from this substrate. Over 100 strains of cellulose-degrading bacteria were isolated from: sewage sludge, hydrolyzer from an agricultural biogas plant, cattle slurry and manure. After physiological characterization of the isolates, 16 strains (representatives of Bacillus, Providencia, and Ochrobactrum genera) were chosen for the construction of a Microbial Consortium with High Cellulolytic Activity, called MCHCA. The selected strains had a high endoglucanase activity (exceeding 0.21 IU/mL CMCase activity) and a wide range of tolerance to various physical and chemical conditions. Lab-scale simulation of biogas production using the selected strains for degradation of maize silage was carried out in a two-bioreactor system, similar to those used in agricultural biogas plants. The obtained results showed that the constructed MCHCA consortium is capable of efficient hydrolysis of maize silage, and increases biogas production by even 38%, depending on the inoculum used for methane fermentation. The results in this work indicate that the mesophilic MCHCA has a great potential for application on industrial scale in agricultural biogas plants. PMID:27014244

  17. The complete genome sequence of Fibrobacter succinogenes S85 reveals a cellulolytic and metabolic specialist.

    Directory of Open Access Journals (Sweden)

    Garret Suen

    Full Text Available Fibrobacter succinogenes is an important member of the rumen microbial community that converts plant biomass into nutrients usable by its host. This bacterium, which is also one of only two cultivated species in its phylum, is an efficient and prolific degrader of cellulose. Specifically, it has a particularly high activity against crystalline cellulose that requires close physical contact with this substrate. However, unlike other known cellulolytic microbes, it does not degrade cellulose using a cellulosome or by producing high extracellular titers of cellulase enzymes. To better understand the biology of F. succinogenes, we sequenced the genome of the type strain S85 to completion. A total of 3,085 open reading frames were predicted from its 3.84 Mbp genome. Analysis of sequences predicted to encode for carbohydrate-degrading enzymes revealed an unusually high number of genes that were classified into 49 different families of glycoside hydrolases, carbohydrate binding modules (CBMs, carbohydrate esterases, and polysaccharide lyases. Of the 31 identified cellulases, none contain CBMs in families 1, 2, and 3, typically associated with crystalline cellulose degradation. Polysaccharide hydrolysis and utilization assays showed that F. succinogenes was able to hydrolyze a number of polysaccharides, but could only utilize the hydrolytic products of cellulose. This suggests that F. succinogenes uses its array of hemicellulose-degrading enzymes to remove hemicelluloses to gain access to cellulose. This is reflected in its genome, as F. succinogenes lacks many of the genes necessary to transport and metabolize the hydrolytic products of non-cellulose polysaccharides. The F. succinogenes genome reveals a bacterium that specializes in cellulose as its sole energy source, and provides insight into a novel strategy for cellulose degradation.

  18. Interactions between Cellulolytic Enzymes with Native, Autohydrolysis, and Technical Lignins and the Effect of a Polysorbate Amphiphile in Reducing Nonproductive Binding.

    Science.gov (United States)

    Fritz, Consuelo; Ferrer, Ana; Salas, Carlos; Jameel, Hasan; Rojas, Orlando J

    2015-12-14

    Understanding enzyme-substrate interactions is critical in designing strategies for bioconversion of lignocellulosic biomass. In this study we monitored molecular events, in situ and in real time, including the adsorption and desorption of cellulolytic enzymes on lignins and cellulose, by using quartz crystal microgravimetry and surface plasmon resonance. The effect of a nonionic surface active molecule was also elucidated. Three lignin substrates relevant to the sugar platform in biorefinery efforts were considered, namely, hardwood autohydrolysis cellulolytic (HWAH), hardwood native cellulolytic (MPCEL), and nonwood native cellulolytic (WSCEL) lignin. In addition, Kraft lignins derived from softwoods (SWK) and hardwoods (HWK) were used as references. The results indicated a high affinity between the lignins with both, monocomponent and multicomponent enzymes. More importantly, the addition of nonionic surfactants at concentrations above their critical micelle concentration reduced remarkably (by over 90%) the nonproductive interactions between the cellulolytic enzymes and the lignins. This effect was hypothesized to be a consequence of the balance of hydrophobic and hydrogen bonding interactions. Moreover, the reduction of surface roughness and increased wettability of lignin surfaces upon surfactant treatment contributed to a lower affinity with the enzymes. Conformational changes of cellulases were observed upon their adsorption on lignin carrying preadsorbed surfactant. Weak electrostatic interactions were determined in aqueous media at pH between 4.8 and 5.5 for the native cellulolytic lignins (MPCEL and WSCEL), whereby a ∼20% reduction in the enzyme affinity was observed. This was mainly explained by electrostatic interactions (osmotic pressure effects) between charged lignins and cellulases. Noteworthy, adsorption of nonionic surfactants onto cellulose, in the form cellulose nanofibrils, did not affect its hydrolytic conversion. Overall, our results

  19. Temporal variations in microbial biomass C and cellulolytic enzyme activity in arable soils: effects of organic matter input

    DEFF Research Database (Denmark)

    Debosz, K.; Rasmussen, Peter Have; Pedersen, A. R.

    1999-01-01

    -OM). The cultivation systems differed in whether their source of fertiliser was mainly mineral or organic, in whether a winter cover crop was grown, and whether straw was mulched or removed. Sampling occurred at approximately monthly intervals, over a period of two years. Distinct temporal variations in microbial...... biomass C concentration and activity of extracellular enzymes of the cellulolytic complex were observed. The temporal pattern was generally similar in the low-OM and high-OM cultivation systems. Temporal variations may have been driven by environmental factors (e.g., temperature and moisture) and crop...

  20. Biosynthesis of fructo-oligosaccharides by Sporotrichum thermophile during submerged batch cultivation in high sucrose media

    DEFF Research Database (Denmark)

    Katapodis, P.; Kalogeris, E.; Kekos, D.;

    2004-01-01

    Biosynthesis of fructo-oligosaccharides (FOS) was observed during growth of the thermophilic fungus Sporotrichum thermophile on media containing high sucrose concentrations. Submerged batch cultivation with the optimum initial sucrose concentration of 250 g/l allowed the production of 12.5 g FOS...

  1. Comparative genomic analysis of the thermophilic biomass-degrading fungi Myceliophthora thermophila and Thielavia terrestris.

    Science.gov (United States)

    Berka, Randy M; Grigoriev, Igor V; Otillar, Robert; Salamov, Asaf; Grimwood, Jane; Reid, Ian; Ishmael, Nadeeza; John, Tricia; Darmond, Corinne; Moisan, Marie-Claude; Henrissat, Bernard; Coutinho, Pedro M; Lombard, Vincent; Natvig, Donald O; Lindquist, Erika; Schmutz, Jeremy; Lucas, Susan; Harris, Paul; Powlowski, Justin; Bellemare, Annie; Taylor, David; Butler, Gregory; de Vries, Ronald P; Allijn, Iris E; van den Brink, Joost; Ushinsky, Sophia; Storms, Reginald; Powell, Amy J; Paulsen, Ian T; Elbourne, Liam D H; Baker, Scott E; Magnuson, Jon; Laboissiere, Sylvie; Clutterbuck, A John; Martinez, Diego; Wogulis, Mark; de Leon, Alfredo Lopez; Rey, Michael W; Tsang, Adrian

    2011-10-02

    Thermostable enzymes and thermophilic cell factories may afford economic advantages in the production of many chemicals and biomass-based fuels. Here we describe and compare the genomes of two thermophilic fungi, Myceliophthora thermophila and Thielavia terrestris. To our knowledge, these genomes are the first described for thermophilic eukaryotes and the first complete telomere-to-telomere genomes for filamentous fungi. Genome analyses and experimental data suggest that both thermophiles are capable of hydrolyzing all major polysaccharides found in biomass. Examination of transcriptome data and secreted proteins suggests that the two fungi use shared approaches in the hydrolysis of cellulose and xylan but distinct mechanisms in pectin degradation. Characterization of the biomass-hydrolyzing activity of recombinant enzymes suggests that these organisms are highly efficient in biomass decomposition at both moderate and high temperatures. Furthermore, we present evidence suggesting that aside from representing a potential reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using classical and molecular genetics.

  2. Comparative genomic analysis of the thermophilic biomass-degrading fungi Myceliophthora thermophila and thielavia terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Berka, Randy; Grigoriev, Igor V.; Otillar, Robert P.; Salamov, Asaf; Grimwood, Jane; Reid, Ian; Ishmael, Nadeeza; john, tricia; Darmond, Corinne; Moisan, Marie-Claude; Henrissat, Bernard; Coutinho, Pedro M.; Lombard, Vincent; Natvig, Donald O.; Lindquist, Erika; Schmutz, Jeremy; Lucas, Susan; Harris, Paul; Powlowski, Justin; Bellemare, Annie; Taylor, David; Butler, Gregory; de Vries, Ronald P.; Allijn, Iris E.; van den Brink, Joost; Ushinsky, Sophia; Storms, Reginald; Powell, Amy J.; Paulsen, Ian T.; Elbourne, Liam D. H.; Baker, Scott E.; Magnuson, Jon K.; LaBoissiere, Sylvie; Martinez, Diego; Wogulis, Mark; Lopez de Leon, Alfredo; Rey, Michael; Tsang, Adrian

    2011-10-02

    Thermostable enzymes and thermophilic cell factories may afford economic advantages in the production of many chemicals and biomass-based fuels. Here we describe and compare the genomes of two thermophilic fungi, Myceliophthora thermophila and Thielavia terrestris. To our knowledge, these genomes are the first described for thermophilic eukaryotes and the first complete telomere-to-telomere genomes for filamentous fungi. Genome analyses and experimental data suggest that both thermophiles are capable of hydrolyzing all major polysaccharides found in biomass. Examination of transcriptome data and secreted proteins suggests that the two fungi use shared approaches in the hydrolysis of cellulose and xylan but distinct mechanisms in pectin degradation. Characterization of the biomass-hydrolyzing activity of recombinant enzymes suggests that these organisms are highly efficient in biomass decomposition at both moderate and high temperatures. Furthermore, we present evidence suggesting that aside from representing a potential reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using classical and molecular genetics.

  3. Comparative genomic analysis of the thermophilic biomass-degrading fungi Myceliophthora thermophila and Thielavia terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Berka, Randy M.; Grigoriev, Igor V.; Otillar, Robert; Salamov, Asaf; Grimwood, Jane; Reid, Ian; Ishmael, Nadeeza; John, Tricia; Darmond, Corinne; Moisan, Marie-Claude; Henrissat, Bernard; Coutinho, Pedro M.; Lombard, Vincent; Natvig, Donald O.; Lindquist, Erika; Schmutz, Jeremy; Lucas, Susan; Harris, Paul; Powlowski, Justin; Bellemare, Annie; Taylor, David; Butler, Gregory; de Vries, Ronald P.; Allijn, Iris E.; van den Brink, Joost; Ushinsky, Sophia; Storms, Reginald; Powell, Amy J.; Paulsen, Ian T.; Elbourne, Liam D. H.; Baker, Scott. E.; Magnuson, Jon; LaBoissiere, Sylvie; Clutterbuck, A. John; Martinez, Diego; Wogulis, Mark; Lopez de Leon, Alfredo; Rey, Michael W.; Tsang, Adrian

    2011-05-16

    Thermostable enzymes and thermophilic cell factories may afford economic advantages in the production of many chemicals and biomass-based fuels. Here we describe and compare the genomes of two thermophilic fungi, Myceliophthora thermophila and Thielavia terrestris. To our knowledge, these genomes are the first described for thermophilic eukaryotes and the first complete telomere-to-telomere genomes for filamentous fungi. Genome analyses and experimental data suggest that both thermophiles are capable of hydrolyzing all major polysaccharides found in biomass. Examination of transcriptome data and secreted proteins suggests that the two fungi use shared approaches in the hydrolysis of cellulose and xylan but distinct mechanisms in pectin degradation. Characterization of the biomass-hydrolyzing activity of recombinant enzymes suggests that these organisms are highly efficient in biomass decomposition at both moderate and high temperatures. Furthermore, we present evidence suggesting that aside from representing a potential reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using classical and molecular genetics.

  4. Use of a Mixture of Thermophilic Enzymes Produced by the Fungus Thermoascus aurantiacus to Enhance the Enzymatic Hydrolysis of the Sugarcane Bagasse Cellulose

    Directory of Open Access Journals (Sweden)

    J. R. Monte

    2010-01-01

    Full Text Available Problem statement: The production of hydrolytic enzymes by T. aurantiacus has been performed under solid-state fermentations using lignocellulosic materials. The influences of the inoculum size and of the fermentation medium on the production of hemicellulases and cellulases were studied. Filtrates from the cultures were used to hydrolyze a pulp of sugarcane bagasse and the produced enzymes were shown to be candidates for use as co-adjuvants in plant saccharification. Aproach: The present study focuses on the effect of different culture conditions on production of cellulases and hemicellulases by T. aurantiacus. It is also provides a possible application of T. aurantiacus enzymes in the degradation of sugarcane bagasse pulp, considering that this thermophilic fungus is a potential source of thermostable enzymes. Results: T. aurantiacus was cultivated on four different agricultural residues: sugarcane bagasse, sugarcane straw, wheat straw and corn cob. Xylanase was produced with much more expressive activity than cellulases. The highest titre of xylanase was obtained on sugarcane straw at 9 days (1679.8 IU g−1; the same was observed for β- glucosidase (29.9 IU g−1 at 6 days. With an inoculum load of 108 spores g−1, the amount of exoglucanase produced by the fungus considerably exceeds that produced with 104 spores g−1. Xylanases and cellulases purified from filtrates of the cultures were investigated to hydrolyze a bagasse pulp prepared with alkaline peroxide. Xylanase or sulphuric acid were used as pretreatments for xylan removal, increasing the cellulase performance on pulp bagasse. However, results revealed that the removal of hemicellulose is not the only main factor limiting the cellulose hydrolysis. Conclusion: Results indicate that the xylanase action on alkaline-pretreated sugar cane bagasse enhances the cellulolytic effect promoted by a commercial cellulase. This study thus presents an evaluation of the

  5. Biodegradation of Aliphatic-aromatic Coplyester under Thermophilic Conditions

    Directory of Open Access Journals (Sweden)

    Elsayed B. Belal

    2013-11-01

    Full Text Available The biodegradation of poly (tetramethylene adipate-co-tetramethylene terephthalate (BTA-copolyester as synthetic polyester was investigated under thermophilic conditions. Two efficient BTA degrading actinomycetes were isolated from compost at thermophilic phase. These strains were identified as Thermobifida fusca and Thermobispora bispora. The degradation rate for BTA films within 7 days was 17.12 and 16.96 mg/week.cm2 by T. fusca and T. bispora, respectively. The optimum BTA40:60 degradation conditions are obtained as pH7 and 55°C. The both strains exhibited a wider substrate spectrum as they are able to degrade synthetic polyesters (BTA40:60, PCL-S MaterBi ZF03U/A and natural polymers (poly-&beta-hydroxybutyric acid (PHB and carboxymethyl cellulose. It was shown that the extracellular hydrolyases activity from the both strains was induced in the presence of BTA-copolyester, while the presence of additional carbon sources such as glucose or a complex medium suppressed enzyme formation. Tributyrin as triglycerides was degraded by the both crude concentrated BTA-hydrolases. In contrast the enzyme was not capable to depolymerize the natural polymers PHB and carboxymethyl cellulose, although the organism itself degraded both types of polymers. The obtained results showed that the degradation rate with T. fusca BTA40:60-hydrolase was 3.67 mg/day.cm2 and was 3.5 mg/day.cm2 with T. bispora BTA40:60-hydrolase. The pH optimum for BTA-hydrolases was 7 with 20 and 100 mM phosphate buffer and it was 6 with 150 mM citrate buffer. Finally, it could be concluded that actinomycetes and their hydrolases play an outstanding role in recycling of biodegradable plastics under thermophilic phase during composting process.

  6. Abiotic and microbiotic factors controlling biofilm formation by thermophilic sporeformers.

    Science.gov (United States)

    Zhao, Yu; Caspers, Martien P M; Metselaar, Karin I; de Boer, Paulo; Roeselers, Guus; Moezelaar, Roy; Nierop Groot, Masja; Montijn, Roy C; Abee, Tjakko; Kort, Remco

    2013-09-01

    One of the major concerns in the production of dairy concentrates is the risk of contamination by heat-resistant spores from thermophilic bacteria. In order to acquire more insight in the composition of microbial communities occurring in the dairy concentrate industry, a bar-coded 16S amplicon sequencing analysis was carried out on milk, final products, and fouling samples taken from dairy concentrate production lines. The analysis of these samples revealed the presence of DNA from a broad range of bacterial taxa, including a majority of mesophiles and a minority of (thermophilic) spore-forming bacteria. Enrichments of fouling samples at 55°C showed the accumulation of predominantly Brevibacillus and Bacillus, whereas enrichments at 65°C led to the accumulation of Anoxybacillus and Geobacillus species. Bacterial population analysis of biofilms grown using fouling samples as an inoculum indicated that both Anoxybacillus and Geobacillus preferentially form biofilms on surfaces at air-liquid interfaces rather than on submerged surfaces. Three of the most potent biofilm-forming strains isolated from the dairy factory industrial samples, including Geobacillus thermoglucosidans, Geobacillus stearothermophilus, and Anoxybacillus flavithermus, have been characterized in detail with respect to their growth conditions and spore resistance. Strikingly, Geobacillus thermoglucosidans, which forms the most thermostable spores of these three species, is not able to grow in dairy intermediates as a pure culture but appears to be dependent for growth on other spoilage organisms present, probably as a result of their proteolytic activity. These results underscore the importance of abiotic and microbiotic factors in niche colonization in dairy factories, where the presence of thermophilic sporeformers can affect the quality of end products. PMID:23851093

  7. Comparative genotyping of Clostridium thermocellum strains isolated from biogas plants: genetic markers and characterization of cellulolytic potential.

    Science.gov (United States)

    Koeck, Daniela E; Zverlov, Vladimir V; Liebl, Wolfgang; Schwarz, Wolfgang H

    2014-07-01

    Clostridium thermocellum is among the most prevalent of known anaerobic cellulolytic bacteria. In this study, genetic and phenotypic variations among C. thermocellum strains isolated from different biogas plants were determined and different genotyping methods were evaluated on these isolates. At least two C. thermocellum strains were isolated independently from each of nine different biogas plants via enrichment on cellulose. Various DNA-based genotyping methods such as ribotyping, RAPD (Random Amplified Polymorphic DNA) and VNTR (Variable Number of Tandem Repeats) were applied to these isolates. One novel approach - the amplification of unknown target sequences between copies of a previously discovered Random Inserted Mobile Element (RIME) - was also tested. The genotyping method with the highest discriminatory power was found to be the amplification of the sequences between the insertion elements, where isolates from each biogas plant yielded a different band pattern. Cellulolytic potentials, optimal growth conditions and substrate spectra of all isolates were characterized to help identify phenotypic variations. Irrespective of the genotyping method used, the isolates from each individual biogas plant always exhibited identical patterns. This is suggestive of a single C. thermocellum strain exhibiting dominance in each biogas plant. The genotypic groups reflect the results of the physiological characterization of the isolates like substrate diversity and cellulase activity. Conversely, strains isolated across a range of biogas plants differed in their genotyping results and physiological properties. Both strains isolated from one biogas plant had the best specific cellulose-degrading properties and might therefore achieve superior substrate utilization yields in biogas fermenters.

  8. Extremely thermophilic microorganisms and their polymer-hidrolytic enzymes

    Directory of Open Access Journals (Sweden)

    Andrade Carolina M.M.C.

    1999-01-01

    Full Text Available Thermophilic and hyperthermophilic microorganisms are found as normal inhabitants of continental and submarine volcanic areas, geothermally heated sea-sediments and hydrothermal vents and thus are considered extremophiles. Several present or potential applications of extremophilic enzymes are reviewed, especially polymer-hydrolysing enzymes, such as amylolytic and hemicellulolytic enzymes. The purpose of this review is to present the range of morphological and metabolic features among those microorganisms growing from 70oC to 100°C and to indicate potential opportunities for useful applications derived from these features.

  9. Genome Sequence and Analysis of the Soil Cellulolytic ActinomyceteThermobifida fusca

    Energy Technology Data Exchange (ETDEWEB)

    Lykidis, Athanasios; Mavromatis, Konstantinos; Ivanova, Natalia; Anderson, Iain; Land, Miriam; DiBartolo, Genevieve; Martinez, Michele; Lapidus, Alla; Lucas, Susan; Copeland, Alex; Richardson, Paul; Wilson,David B.; Kyrpides, Nikos

    2007-02-01

    Thermobifida fusca is a moderately thermophilic soilbacterium that belongs to Actinobacteria. 3 It is a major degrader ofplant cell walls and has been used as a model organism for the study of 4secreted, thermostable cellulases. The complete genome sequence showedthat T. fusca has a 5 single circular chromosome of 3642249 bp predictedto encode 3117 proteins and 65 RNA6 species with a coding densityof 85percent. Genome analysis revealed the existence of 29 putative 7glycoside hydrolases in addition to the previously identified cellulasesand xylanases. The 8 glycosyl hydrolases include enzymes predicted toexhibit mainly dextran/starch and xylan 9 degrading functions. T. fuscapossesses two protein secretion systems: the sec general secretion 10system and the twin-arginine translocation system. Several of thesecreted cellulases have 11 sequence signatures indicating theirsecretion may be mediated by the twin-arginine12 translocation system. T.fusca has extensive transport systems for import of carbohydrates 13coupled to transcriptional regulators controlling the expression of thetransporters and14 glycosylhydrolases. In addition to providing anoverview of the physiology of a soil 15 actinomycete, this study presentsinsights on the transcriptional regulation and secretion of16 cellulaseswhich may facilitate the industrial exploitation of thesesystems.

  10. RICHNESS, CELLULOLYTIC ACTIVITY, AND FUNGICIDE SUSCEPTIBILITY OF FUNGI FROM A BIRD BIOLOGICAL COLLECTION

    Directory of Open Access Journals (Sweden)

    Henry Arenas-Castro

    2015-11-01

    Full Text Available ABSTRACTBiological collections in natural history museums serve important purposes to the scientific community and the general public, however, their value and utility might be diminished by biodeterioration. We studied a biological collection that represents more than sixty years of avifauna sampling of Colombia, the country with the highest bird diversity. An initial inspection of the collection showed that the general appearance of some specimens was compromised by mold-like growth on their surfaces. We aimed at (i identifying the taxonomic affiliation of these fungi, (ii evaluating their cellulolytic activity, and (iii probing chemical agents that could be utilized to control their growth. The most common fungi genera were Aspergillus, Penicillium, Chaetomium, and Trichophyton, most of which can degrade cellulose. Zinc chloride and salicylic acid showed to be effective fungicides. Based on this, we propose some actions to control the fungi-pest in this biological collection of birds.RESUMENLas colecciones biológicas en los museos de historia natural juegan un papel importante tanto para la comunidad científica como para el público en general. Sin embargo, su valor y utilidad pueden verse afectados por la biodeterioración de sus ejemplares. Se estudio una colección biológica de aves que representa más de sesenta años de esfuerzo de muestreo de la avifauna del país más rico en aves. Una inspección inicial mostró que la apariencia general de algunos de los especímenes de la colección se encontraba afectada por hongos. Los objetivos de este estudio fueron (i identificar la afiliación taxonómica de los hongos, (ii determinar la actividad celulolítica y (iii probar agentes químicos que puedan ser utilizados para controlar su desarrollo. Los géneros de hongos más comunes fueron Aspergillus, Penicillium, Chaetomium y Trichophyton, de los cuales la mayoría presentan la capacidad de degradar celulosa. Adicionalmente, el cloruro de

  11. Bioleaching of chalcopyrite by mixed culture of moderately thermophilic microorganisms

    Institute of Scientific and Technical Information of China (English)

    WU Chang-bin; ZENG Wei-min; ZHOU Hong-bo; FU Bo; HUANG Ju-fang; QIU Guan-zhou; WANG Dian-zuo

    2007-01-01

    A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs) samples collected from several sulphide mines in China, and the bioleaching of chalcopyrite was conducted both in shake flask and bioreactor.The results show that in the shake flask, the mixture can tolerate 50 g/L chalcopyrite after being acclimated to gradually increased concentrations of chalcopyrite. The copper extraction increases obviously in bioleaching of chalcopyrite with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min, 74% copper can be extracted in the pulp of 50 g/L chalcopyrite after 20 d. Compared with copper extractions of mesophilic culture, unacclimated culture and acclimated culture without addition of yeast extract, that of accliniated culture with addition of yeast extract is increased by 53%, 44% and 16%,respectively. In a completely stirred tank reactor, the mass fraction of copper and total iron extraction reach up to 81% and 56%,respectively. The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from chalcopyrite effectively.

  12. Report: antibiotic production by thermophilic Bacillus specie SAT-4.

    Science.gov (United States)

    Muhammad, Syed Aun; Ahmad, Safia; Hameed, Abdul

    2009-07-01

    Production of antimicrobial compounds seems to be a general phenomenon for most bacteria. The prevalence of antimicrobial resistance among key microbial pathogens is increasing at an alarming rate worldwide. Current solutions involve development of a more rationale approach to antibiotic use and discover of new antimicrobials. Bacillus species produce a large number of biological compounds active against bacteria, fungi, protozoa and viruses. The process of production usually involves screening of wide range of microorganisms, testing and modification. Production is carried out using fermentation. Thermophilic spore-forming, gram positive, motile rod bacterial strains were isolated from the Thar Desserts, Sindh Province, Pakistan. These strains were screened and checked for antibacterial activity. The best activity was observed by SAT4 against Micrococcus luteus, Staphylococcus aureus and Pseudomonas aeroginosa. The activity was only observed against gram positive bacteria and no activity was seen against Pseudomonas aeroginosa. Thermophilic Bacillus specie SAT4 was found to be active in the fermentation process to produce the antimicrobial agents. Further optimizations of different conditions (time of incubation, media, pH, glucose concentrations, nitrogen concentrations, and temperature) for antimicrobial production by the selected bacterial strain was performed. Agar diffusion assay was performed to evaluate the antibacterial activity. Optimum conditions for the production of antimicrobials by selected isolate were observed to be 48 hour, pH 5, temperature 55 degrees C, 2% glucose and 1.5% nitrogen concentration. This newly isolated bacterial strain has great potential for antimicrobial production at industrial scale. PMID:19553186

  13. Biomass production and energy source of thermophiles in a Japanese alkaline geothermal pool.

    Science.gov (United States)

    Kimura, Hiroyuki; Mori, Kousuke; Nashimoto, Hiroaki; Hattori, Shohei; Yamada, Keita; Koba, Keisuke; Yoshida, Naohiro; Kato, Kenji

    2010-02-01

    Microbial biomass production has been measured to investigate the contribution of planktonic bacteria to fluxations in dissolved organic matter in marine and freshwater environments, but little is known about biomass production of thermophiles inhabiting geothermal and hydrothermal regions. The biomass production of thermophiles inhabiting an 85 degrees C geothermal pool was measured by in situ cultivation using diffusion chambers. The thermophiles' growth rates ranged from 0.43 to 0.82 day(-1), similar to those of planktonic bacteria in marine and freshwater habitats. Biomass production was estimated based on cellular carbon content measured directly from the thermophiles inhabiting the geothermal pool, which ranged from 5.0 to 6.1 microg C l(-1) h(-1). This production was 2-75 times higher than that of planktonic bacteria in other habitats, because the cellular carbon content of the thermophiles was much higher. Quantitative PCR and phylogenetic analysis targeting 16S rRNA genes revealed that thermophilic H2-oxidizing bacteria closely related to Calderobacterium and Geothermobacterium were dominant in the geothermal pool. Chemical analysis showed the presence of H2 in gases bubbling from the bottom of the geothermal pool. These results strongly suggested that H2 plays an important role as a primary energy source of thermophiles in the geothermal pool.

  14. Knowledge-based discovery for designing CRISPR-CAS systems against invading mobilomes in thermophiles.

    Science.gov (United States)

    Chellapandi, P; Ranjani, J

    2015-09-01

    Clustered regularly interspaced short palindromic repeats (CRISPRs) are direct features of the prokaryotic genomes involved in resistance to their bacterial viruses and phages. Herein, we have identified CRISPR loci together with CRISPR-associated sequences (CAS) genes to reveal their immunity against genome invaders in the thermophilic archaea and bacteria. Genomic survey of this study implied that genomic distribution of CRISPR-CAS systems was varied from strain to strain, which was determined by the degree of invading mobiloms. Direct repeats found to be equal in some extent in many thermopiles, but their spacers were differed in each strain. Phylogenetic analyses of CAS superfamily revealed that genes cmr, csh, csx11, HD domain, devR were belonged to the subtypes of cas gene family. The members in cas gene family of thermophiles were functionally diverged within closely related genomes and may contribute to develop several defense strategies. Nevertheless, genome dynamics, geological variation and host defense mechanism were contributed to share their molecular functions across the thermophiles. A thermophilic archaean, Thermococcus gammotolerans and thermophilic bacteria, Petrotoga mobilis and Thermotoga lettingae have shown superoperons-like appearance to cluster cas genes, which were typically evolved for their defense pathways. A cmr operon was identified with a specific promoter in a thermophilic archaean, Caldivirga maquilingensis. Overall, we concluded that knowledge-based genomic survey and phylogeny-based functional assignment have suggested for designing a reliable genetic regulatory circuit naturally from CRISPR-CAS systems, acquired defense pathways, to thermophiles in future synthetic biology.

  15. A strict anaerobic extreme thermophilic hydrogen-producing culture enriched from digested household waste

    DEFF Research Database (Denmark)

    Karakashev, Dimitar Borisov; Kotay, Shireen Meher; Trably, Eric;

    2009-01-01

    The aim of this study was to enrich, characterize and identify strict anaerobic extreme thermophilic hydrogen (H-2) producers from digested household solid wastes. A strict anaerobic extreme thermophilic H-2 producing bacterial culture was enriched from a lab-scale digester treating household...... to the genera Bacillus and Clostridium. Relative abundance of the culture members, assessed by fluorescence in situ hybridization, were 87 +/- 5% and 13 +/- 5% for Bacillus and Clostridium, respectively. An extreme thermophilic, strict anaerobic, mixed microbial culture with H-2-producing potential was enriched...

  16. Microbial community dynamics in thermophilic undefined milk starter cultures.

    Science.gov (United States)

    Parente, Eugenio; Guidone, Angela; Matera, Attilio; De Filippis, Francesca; Mauriello, Gianluigi; Ricciardi, Annamaria

    2016-01-18

    Model undefined thermophilic starter cultures were produced from raw milk of nine pasta-filata cheesemaking plants using a selective procedure based on pasteurization and incubation at high temperature with the objective of studying the microbial community dynamics and the variability in performances under repeated (7-13) reproduction cycles with backslopping. The traditional culture-dependent approach, based on random isolation and molecular characterization of isolates was coupled to the determination of pH and the evaluation of the ability to produce acid and fermentation metabolites. Moreover, a culture-independent approach based on amplicon-targeted next-generation sequencing was employed. The microbial diversity was evaluated by 16S rRNA gene sequencing (V1-V3 regions), while the microdiversity of Streptococcus thermophilus populations was explored by using novel approach based on sequencing of partial amplicons of the phosphoserine phosphatase gene (serB). In addition, the occurrence of bacteriophages was evaluated by qPCR and by multiplex PCR. Although it was relatively easy to select for a community dominated by thermophilic lactic acid bacteria (LAB) within a single reproduction cycle, final pH, LAB populations and acid production activity fluctuated over reproduction cycles. Both culture-dependent and -independent methods showed that the cultures were dominated by either S. thermophilus or Lactobacillus delbrueckii subsp. lactis or by both species. Nevertheless, subdominant mesophilic species, including lactococci and spoilage organisms, persisted at low levels. A limited number of serB sequence types (ST) were present in S. thermophilus populations. L. delbrueckii and Lactococcus lactis bacteriophages were below the detection limit of the method used and high titres of cos type S. thermophilus bacteriophages were detected in only two cases. In one case a high titre of bacteriophages was concurrent with a S. thermophilus biotype shift in the culture

  17. Enhanced cell-surface display and secretory production of cellulolytic enzymes with Saccharomyces cerevisiae Sed1 signal peptide.

    Science.gov (United States)

    Inokuma, Kentaro; Bamba, Takahiro; Ishii, Jun; Ito, Yoichiro; Hasunuma, Tomohisa; Kondo, Akihiko

    2016-11-01

    Recombinant yeast strains displaying aheterologous cellulolytic enzymes on their cell surfaces using a glycosylphosphatidylinositol (GPI) anchoring system are a promising strategy for bioethanol production from lignocellulosic materials. A crucial step for cell wall localization of the enzymes is the intracellular transport of proteins in yeast cells. Therefore, the addition of a highly efficient secretion signal sequence is important to increase the amount of the enzymes on the yeast cell surface. In this study, we demonstrated the effectiveness of a novel signal peptide (SP) sequence derived from the Saccharomyces cerevisiae SED1 gene for cell-surface display and secretory production of cellulolytic enzymes. Gene cassettes with SP sequences derived from S. cerevisiae SED1 (SED1SP), Rhizopus oryzae glucoamylase (GLUASP), and S. cerevisiae α-mating pheromone (MFα1SP) were constructed for cell-surface display of Aspergillus aculeatus β-glucosidase (BGL1) and Trichoderma reesei endoglucanase II (EGII). These gene cassettes were integrated into the S. cerevisiae genome. The recombinant strains with the SED1SP showed higher cell-surface BGL and EG activities than those with the conventional SP sequences (GLUASP and MFα1SP). The novel SP sequence also improved the secretory production of BGL and EG in S. cerevisiae. The extracellular BGL activity of the recombinant strains with the SED1SP was 1.3- and 1.9-fold higher than the GLUASP and MFα1SP strains, respectively. Moreover, the utilization of SED1SP successfully enhanced the secretory production of BGL in Pichia pastoris. The utilization of the novel SP sequence is a promising option for highly efficient cell-surface display and secretory production of heterologous proteins in various yeast species. Biotechnol. Bioeng. 2016;113: 2358-2366. © 2016 Wiley Periodicals, Inc. PMID:27183011

  18. Structural insights into cellulolytic and chitinolytic enzymes revealing crucial residues of insect β-N-acetyl-D-hexosaminidase.

    Directory of Open Access Journals (Sweden)

    Tian Liu

    Full Text Available The chemical similarity of cellulose and chitin supports the idea that their corresponding hydrolytic enzymes would bind β-1,4-linked glucose residues in a similar manner. A structural and mutational analysis was performed for the plant cellulolytic enzyme BGlu1 from Oryza sativa and the insect chitinolytic enzyme OfHex1 from Ostrinia furnacalis. Although BGlu1 shows little amino-acid sequence or topological similarity with OfHex1, three residues (Trp(490, Glu(328, Val(327 in OfHex1, and Trp(358, Tyr(131 and Ile(179 in BGlu1 were identified as being conserved in the +1 sugar binding site. OfHex1 Glu(328 together with Trp(490 was confirmed to be necessary for substrate binding. The mutant E328A exhibited a 8-fold increment in K(m for (GlcNAc(2 and a 42-fold increment in K(i for TMG-chitotriomycin. A crystal structure of E328A in complex with TMG-chitotriomycin was resolved at 2.5 Å, revealing the obvious conformational changes of the catalytic residues (Glu(368 and Asp(367 and the absence of the hydrogen bond between E328A and the C3-OH of the +1 sugar. V327G exhibited the same activity as the wild-type, but acquired the ability to efficiently hydrolyse β-1,2-linked GlcNAc in contrast to the wild-type. Thus, Glu(328 and Val(327 were identified as important for substrate-binding and as glycosidic-bond determinants. A structure-based sequence alignment confirmed the spatial conservation of these three residues in most plant cellulolytic, insect and bacterial chitinolytic enzymes.

  19. Carbohydrate utilization patterns for the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus reveal broad growth substrate preferences

    NARCIS (Netherlands)

    Vanfossen, A.L.; Verhaart, M.R.A.; Kengen, S.W.M.; Kelly, R.M.

    2009-01-01

    Co-utilization of hexoses and pentoses derived from lignocellulose is an attractive trait in microorganisms considered for consolidated biomass processing to biofuels. This issue was examined for the H2-producing, extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus growing on indiv

  20. Pyrophosphate as a central energy carrier in the hydrogen-producing extremely thermophilic Caldicellulosiruptor saccharolyticus

    NARCIS (Netherlands)

    Bielen, A.A.M.; Willquist, K.; Engman, J.; Oost, van der J.; Niel, van E.W.J.; Kengen, S.W.M.

    2010-01-01

    The role of inorganic pyrophosphate (PPi) as an energy carrier in the central metabolism of the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus was investigated. In agreement with its annotated genome sequence, cell extracts were shown to exhibit PPi-dependent phosphofructokina

  1. Bioleaching of metals from electronic scrap by moderately thermophilic acidophilic bacteria

    NARCIS (Netherlands)

    Ilyas, Sadia; Anwar, Munir A.; Niazi, Shahida B.; Ghauri, M. Afzal

    2007-01-01

    The present work was aimed at studying the bioleachability of metals from electronic scrap by the selected moderately thermophilic strains of acidophilic chemolithotrophic and acidophilic heterotrophic bacteria. These included Sulfobacillus thermosulfidooxidans and an unidentified acidophilic hetero

  2. Solid-Phase Thermophilic Aerobic Reactor (STAR) Processing of Fecal, Food, and Plant Residues

    OpenAIRE

    2006-01-01

    A description of the Solid Waste Resource Recovery ALS-NSCORT projects: Solid Phase Thermophilic Aerobic Reactor (STAR), Nitrogen Cycling in Advanced Life Support Systems, and Plant-based Anaerobic-Aerobic Bioreactor Linked Operation (PAABLO). 26 pages.

  3. A novel membrane distillation-thermophilic bioreactor system: biological stability and trace organic compound removal.

    Science.gov (United States)

    Wijekoon, Kaushalya C; Hai, Faisal I; Kang, Jinguo; Price, William E; Guo, Wenshan; Ngo, Hao H; Cath, Tzahi Y; Nghiem, Long D

    2014-05-01

    The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs was high and was not significantly affected by the conditions of the bioreactor. All TrOCs investigated here were highly removed (>95%) by the MDBR system. Biodegradation, sludge adsorption, and rejection by MD contribute to the removal of TrOCs by MDBR treatment. PMID:24658107

  4. Hydrogen production by hyperthermophilic and extremely thermophilic bacteria and archaea: mechanisms for reductant disposal

    NARCIS (Netherlands)

    Verhaart, M.R.A.; Bielen, A.A.M.; Oost, van der J.; Stams, A.J.M.; Kengen, S.W.M.

    2010-01-01

    Hydrogen produced from biomass by bacteria and archaea is an attractive renewable energy source. However, to make its application more feasible, microorganisms are needed with high hydrogen productivities. For several reasons, hyperthermophilic and extremely thermophilic bacteria and archaea are pro

  5. Genetics of thermophilic bacteria. [Bacillus stearothermophilus:a2

    Energy Technology Data Exchange (ETDEWEB)

    Welker, N.E.

    1991-01-01

    Organisms adapted to high temperature have evolved a variety of unique solutions to the biochemical problems imposed by this environment. Adaptation is commonly used to describe the biochemical properties of organisms which have become adapted to their environment (genetic adaptation). It can also mean the direct response-at the cellular level-of an organism to changes in temperature (physiological adaptation). Thermophilic bacilli (strains of Bacillus stearothermophilus) can exhibit a variety of biochemical adaptations in response to changes in temperature. These include changes in the composition and stability of the membrane, metabolic potential, the transport of amino acids, regulatory mechanisms, ribose methylation of tRNA, protein thermostability, and nutritional requirements. The objectives of the research were to develop efficient and reliable genetic systems to analyze and manipulate B. Stearothermophilus, and to use these systems initiate a biochemical, molecular, and genetic investigations of genes that are required for growth at high temperature.

  6. Characterization of a thermophilic bacteriophage of Geobacillus kaustophilus.

    Science.gov (United States)

    Marks, Timothy J; Hamilton, Paul T

    2014-10-01

    GBK2 is a bacteriophage, isolated from a backyard compost pile, that infects the thermophile Geobacillus kaustophilus. GBK2 has a circularly permuted genome of 39,078 bp with a G+C content of 43 %. Annotation of the genome reveals 62 putative open reading frames (ORFs), 25 of which (40.3 %) show homology to known proteins and 37 of which (59.7 %) are proteins with unknown functions. Twelve of the identified ORFs had the greatest homology to genes from the phage SPP1, a phage that infects the mesophile Bacillus subtilis. The overall genomic arrangement of GBK2 is similar to that of SPP1, with the majority of GBK2 SPP1-like genes coding for proteins involved in DNA replication and metabolism.

  7. Biocorrosive Thermophilic Microbial Communities in Alaskan North Slope Oil Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, Kathleen E.; Gieg, Lisa M.; Parisi, Victoria A.; Tanner, Ralph S.; Green Tringe, Susannah; Bristow, Jim; Suflita, Joseph M.

    2009-09-16

    Corrosion of metallic oilfield pipelines by microorganisms is a costly but poorly understood phenomenon, with standard treatment methods targeting mesophilic sulfatereducing bacteria. In assessing biocorrosion potential at an Alaskan North Slope oil field, we identified thermophilic hydrogen-using methanogens, syntrophic bacteria, peptideand amino acid-fermenting bacteria, iron reducers, sulfur/thiosulfate-reducing bacteria and sulfate-reducing archaea. These microbes can stimulate metal corrosion through production of organic acids, CO2, sulfur species, and via hydrogen oxidation and iron reduction, implicating many more types of organisms than are currently targeted. Micromolar quantities of putative anaerobic metabolites of C1-C4 n-alkanes in pipeline fluids were detected, implying that these low molecular weight hydrocarbons, routinely injected into reservoirs for oil recovery purposes, are biodegraded and provide biocorrosive microbial communities with an important source of nutrients.

  8. Ribotyping Identification of Thermophilic Bacterium from Papandayan Crater

    Directory of Open Access Journals (Sweden)

    Akhmaloka

    2006-05-01

    Full Text Available A few thermophilic bacteria were isolated from a hot spring located in Papandayan Crater, Garut. One of the organisms showed a well growth at temperature of up to 80oC. Chromosomal DNA from the organism was isolated and used to amplify 16S rRNA gene fragment. The gene was amplified by a set of universal primers (27F and 1492R resulting in a 1.5 kb DNA fragment. The gene was cloned and sequenced. The phylogenetic tree, homological analysis, and detailed comparison of the sequences showed that 16S rRNA gene sequence of the Papandayan isolate is unique compared to other known strains, however the sequence had closest similarities with Bacillus caldolyticus and Bacillus caldotenax.

  9. Pathway engineering to improve ethanol production by thermophilic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Lynd, L.R.

    1998-12-31

    Continuation of a research project jointly funded by the NSF and DOE is proposed. The primary project goal is to develop and characterize strains of C. thermocellum and C. thermosaccharolyticum having ethanol selectivity similar to more convenient ethanol-producing organisms. An additional goal is to document the maximum concentration of ethanol that can be produced by thermophiles. These goals build on results from the previous project, including development of most of the genetic tools required for pathway engineering in the target organisms. As well, we demonstrated that the tolerance of C. thermosaccharolyticum to added ethanol is sufficiently high to allow practical utilization should similar tolerance to produced ethanol be demonstrated, and that inhibition by neutralizing agents may explain the limited concentrations of ethanol produced in studies to date. Task 1 involves optimization of electrotransformation, using either modified conditions or alternative plasmids to improve upon the low but reproducible transformation, frequencies we have obtained thus far.

  10. Bioleaching of pollymetallic sulphide concentrate using thermophilic bacteria

    Directory of Open Access Journals (Sweden)

    Vuković Milovan

    2014-01-01

    Full Text Available An extreme thermophilic, iron-sulphur oxidising bacterial culture was isolated and adapted to tolerate high metal and solids concentrations at 70°C. Following isolation and adaptation, the culture was used in a batch bioleach test employing a 5-l glass standard magnetic agitated and aerated reactor, for the bioleaching of a copper-lead-zinc collective concentrate. The culture exhibited stable leach performance over the period of leach operation and overall copper and zinc extractions higher than 97%. Lead sulphide is transformed into lead sulphate remaining in the bioleach residue due to the low solubility in sulphate media. Brine leaching of bioleach residue yields 95% lead extraction. [Projekat Ministarstva nauke Republike Srbije, br. 34023

  11. The bioleaching of different sulfide concentrates using thermophilic bacteria

    Science.gov (United States)

    Torres, F.; Blázquez, M. L.; González, F.; Ballester, A.; Mier, J. L.

    1995-05-01

    The bioleaching of different mineral sulfide concentrates with thermophilic bacteria (genus Sulfolobus @#@) was studied. Since the use of this type of bacteria in leaching systems involves stirring and the control of temperature, the influence of the type of stirring and the pulp density on dissolution rates was studied in order to ascertain the optimum conditions for metal recovery. At low pulp densities, the dissolution kinetic was favored by pneumatic stirring, but for higher pulp densities, orbital stirring produced the best results. A comparative study of three differential concentrates, one mixed concentrate, and one global concentrate was made. Copper and iron extraction is directly influenced by bacterial activity, while zinc dissolution is basically due to an indirect mechanism that is activated in the presence of copper ions. Galvanic interactions between the different sulfides favors the selective bioleaching of some phases (sphalerite and chalcopyrite) and leads to high metal recovery rates. However, the formation of galvanic couples depends on the type of concentrate.

  12. Draft Genome Sequences of Four Thermophilic Spore Formers Isolated from a Dairy-Processing Environment

    Science.gov (United States)

    Caspers, Martien P. M.; Boekhorst, Jos; de Jong, Anne; Kort, Remco; Nierop Groot, Masja

    2016-01-01

    Spores of thermophilic spore-forming bacteria are a common cause of contamination in dairy products. Here, we report draft genome sequences of four thermophilic strains from a milk-processing plant or standard milk, namely, a Geobacillus thermoglucosidans isolate (TNO-09.023), Geobacillus stearothermophilus TNO-09.027, and two Anoxybacillus flavithermus isolates (TNO-09.014 and TNO-09.016). PMID:27516503

  13. Draft Genome Sequences of Four Thermophilic Spore Formers Isolated from a Dairy-Processing Environment.

    Science.gov (United States)

    Caspers, Martien P M; Boekhorst, Jos; de Jong, Anne; Kort, Remco; Nierop Groot, Masja; Abee, Tjakko

    2016-01-01

    Spores of thermophilic spore-forming bacteria are a common cause of contamination in dairy products. Here, we report draft genome sequences of four thermophilic strains from a milk-processing plant or standard milk, namely, a Geobacillus thermoglucosidans isolate (TNO-09.023), Geobacillus stearothermophilus TNO-09.027, and two Anoxybacillus flavithermus isolates (TNO-09.014 and TNO-09.016). PMID:27516503

  14. Cloning and sequencing of the gene encoding thermophilic beta-amylase of Clostridium thermosulfurogenes.

    OpenAIRE

    Kitamoto, N; Yamagata, H; Kato, T; Tsukagoshi, N; Udaka, S

    1988-01-01

    A gene coding for thermophilic beta-amylase of Clostridium thermosulfurogenes was cloned into Bacillus subtilis, and its nucleotide sequence was determined. The nucleotide sequence suggested that the thermophilic beta-amylase is translated from monocistronic mRNA as a secretory precursor with a signal peptide of 32 amino acid residues. The deduced amino acid sequence of the mature beta-amylase contained 519 residues with a molecular weight of 57,167. The amino acid sequence of the C. thermosu...

  15. [The thermophilic streptomycetes flora in milk powders and condensed milk products (author's transl)].

    Science.gov (United States)

    Falkowski, J

    1978-08-01

    247 specimens of powdered milk and 165 of condensed milk were tested for their contamination with thermophile Streptomycetes. Colonies of these contaminants were isolated from all specimens of powdered milk and from 73 samples of condensed sweeted milk. The isolated strains corresponded with the following species of thermophilic Streptomycetes: Thermoactinomyces vulgaris, Tsiklinsky 1899, Thermoactinomyces vulgaris, Tsiklinsky 1899 "giant colonies", Micromonospora sp. (Agre et al., 1).

  16. Presence and potential role of thermophilic bacteria in temperate terrestrial environments

    Science.gov (United States)

    Portillo, M. C.; Santana, M.; Gonzalez, J. M.

    2012-01-01

    Organic sulfur and nitrogen are major reservoirs of these elements in terrestrial systems, although their cycling remains to be fully understood. Both sulfur and nitrogen mineralization are directly related to microbial metabolism. Mesophiles and thermophiles were isolated from temperate environments. Thermophilic isolates were classified within the Firmicutes, belonging to the Geobacillus, Brevibacillus, and Ureibacillus genera, and showed optimum growth temperatures between 50°C and 60°C. Sulfate and ammonium produced were higher during growth of thermophiles both for isolated strains and natural bacterial assemblages. They were positively related to organic nutrient load. Temperature also affected the release of sulfate and ammonium by thermophiles. Quantitative, real-time reverse-transcription polymerase chain reaction on environmental samples indicated that the examined thermophilic Firmicutes represented up to 3.4% of the total bacterial community RNA. Temperature measurements during summer days showed values above 40°C for more than 10 h a day in soils from southern Spain. These results support a potential role of thermophilic bacteria in temperate terrestrial environments by mineralizing organic sulfur and nitrogen ruled by the existence and length of warm periods.

  17. Start-up and HRT Influence in Thermophilic and Mesophilic Anaerobic Digesters Seeded with Waste Activated Sludge

    OpenAIRE

    Benabdallah, El-Hadj T.; Dosta, J.; Mata-Alvarez, J.

    2007-01-01

    Since thermophilic anaerobic digestion represents an efficient alternative to mesophilic anaerobic digestion, multiple studies have been developed to compare their performance and viability. One of the problems related to thermophilic anaerobic digestion is the availability of an adequate seed to start-up the process. The goal of this study is to evaluate the possibility of using waste activated sludge (WAS) as a seed for both mesophilic (35 °C) and thermophilic (55 °C) anaerobic digesters...

  18. Conjugative plasmid transfer from Escherichia coli is a versatile approach for genetic transformation of thermophilic Bacillus and Geobacillus species.

    Science.gov (United States)

    Tominaga, Yurie; Ohshiro, Takashi; Suzuki, Hirokazu

    2016-05-01

    We previously demonstrated efficient transformation of the thermophile Geobacillus kaustophilus HTA426 using conjugative plasmid transfer from Escherichia coli BR408. To evaluate the versatility of this approach to thermophile transformation, this study examined genetic transformation of various thermophilic Bacillus and Geobacillus spp. using conjugative plasmid transfer from E. coli strains. E. coli BR408 successfully transferred the E. coli-Geobacillus shuttle plasmid pUCG18T to 16 of 18 thermophiles with transformation efficiencies between 4.1 × 10(-7) and 3.8 × 10(-2)/recipient. Other E. coli strains that are different from E. coli BR408 in intracellular DNA methylation also generated transformants from 9 to 15 of the 18 thermophiles, including one that E. coli BR408 could not transform, although the transformation efficiencies of these strains were generally lower than those of E. coli BR408. The conjugation was performed by simple incubation of an E. coli donor and a thermophile recipient without optimization of experimental conditions. Moreover, thermophile transformants were distinguished from abundant E. coli donor only by high temperature incubation. These observations suggest that conjugative plasmid transfer, particularly using E. coli BR408, is a facile and versatile approach for plasmid introduction into thermophilic Bacillus and Geobacillus spp., and potentially a variety of other thermophiles.

  19. Effect of Feeding Palm Oil By-Products Based Diets on Total Bacteria, Cellulolytic Bacteria and Methanogenic Archaea in the Rumen of Goats

    OpenAIRE

    Abubakr, Abdelrahim; Alimon, Abdul Razak; Yaakub, Halimatun; Abdullah, Norhani; Ivan, Michael

    2014-01-01

    Rumen microorganisms are responsible for digestion and utilization of dietary feeds by host ruminants. Unconventional feed resources could be used as alternatives in tropical areas where feed resources are insufficient in terms of quality and quantity. The objective of the present experiment was to evaluate the effect of diets based on palm oil (PO), decanter cake (DC) or palm kernel cake (PKC) on rumen total bacteria, selected cellulolytic bacteria, and methanogenic archaea. Four diets: cont...

  20. A culture-dependent survey of thermophilic bacteria from hot springs in Xiamen area in China

    Institute of Scientific and Technical Information of China (English)

    YANG Bo; OUYANG Jianping; AO Jingqun; CHEN Xinhua

    2009-01-01

    Microbes are believed to play important roles in ecosystem function in many environments. The hot springs of Xiamen Island are close to the Xiamen Sea, and may have some characteristics different from those of inland hot springs. Microbes living in the hot springs of Xiamen may have new characteristics. However, little is known about microbial communities of hot springs close to the Xiamen Sea. A cuhure-dependent survey of microbial population in the Xiamen hot springs was pcrformed by using an approach combining total cellular protein profile identification and 16S rRNA gene sequencing. A total of 328 isolates of bacteria were obtained from liquid and sediment samples from the Xiamen hot springs, including neutrophilie thermophilic bacteria and moderately thermophilic acidophiles. Neutrophilic thermophilic bacteria, which grow at a temperature range of 55-90℃ including Rhodothermus marinus (Strain 1) , Thermus thermophilus (Strain 2), Thermus thiopara (Strain 3) , Geobacillus stearothermophilus(Strain 4) , Geobacillus thermoleovorans (Strain 5) , and Pseudomonas pseudoal-caligenes (Strain 6), were recovered by 2216E plates. Moderately thermophilic acidophiles, which can grow at temperatures above 50℃ and a pH range of 1. 8-3.5 such as Alicyclobacillus acidoterrestris (Strain 8) , Sul-fobacillus acidophilus (Strain 9), and Sulfobacillus thermosulfidooxidans (Strain 10), were isolated on selective solid medium containing sulfur and Fe2+. Among these strains, Rhodothermus marinus, Thermus thermophilus and Geobacillus stearothermophilus are not only thermophilcs, but also halophiles. One bacterium strain (Strain 6) shared 99% nucleotide sequence homology with Pseudomonas pseudoalcaligenes on the 16S rRNA gene se-quence, but was quite different from Pseudomonas pseudoalcaligenes in biological characteristics, suggesting that it may represent a novel thermophilic species. Results indicated that various species of neutrophilic thermophiles and moderately thermophilic

  1. Extremely thermophilic microorganisms as metabolic engineering platforms for production of fuels and industrial chemicals.

    Science.gov (United States)

    Zeldes, Benjamin M; Keller, Matthew W; Loder, Andrew J; Straub, Christopher T; Adams, Michael W W; Kelly, Robert M

    2015-01-01

    Enzymes from extremely thermophilic microorganisms have been of technological interest for some time because of their ability to catalyze reactions of industrial significance at elevated temperatures. Thermophilic enzymes are now routinely produced in recombinant mesophilic hosts for use as discrete biocatalysts. Genome and metagenome sequence data for extreme thermophiles provide useful information for putative biocatalysts for a wide range of biotransformations, albeit involving at most a few enzymatic steps. However, in the past several years, unprecedented progress has been made in establishing molecular genetics tools for extreme thermophiles to the point that the use of these microorganisms as metabolic engineering platforms has become possible. While in its early days, complex metabolic pathways have been altered or engineered into recombinant extreme thermophiles, such that the production of fuels and chemicals at elevated temperatures has become possible. Not only does this expand the thermal range for industrial biotechnology, it also potentially provides biodiverse options for specific biotransformations unique to these microorganisms. The list of extreme thermophiles growing optimally between 70 and 100°C with genetic toolkits currently available includes archaea and bacteria, aerobes and anaerobes, coming from genera such as Caldicellulosiruptor, Sulfolobus, Thermotoga, Thermococcus, and Pyrococcus. These organisms exhibit unusual and potentially useful native metabolic capabilities, including cellulose degradation, metal solubilization, and RuBisCO-free carbon fixation. Those looking to design a thermal bioprocess now have a host of potential candidates to choose from, each with its own advantages and challenges that will influence its appropriateness for specific applications. Here, the issues and opportunities for extremely thermophilic metabolic engineering platforms are considered with an eye toward potential technological advantages for high

  2. Reduction of hexavalent chromium by the thermophilic methanogen Methanothermobacter thermautotrophicus

    Science.gov (United States)

    Singh, Rajesh; Dong, Hailiang; Liu, Deng; Zhao, Linduo; Marts, Amy R.; Farquhar, Erik; Tierney, David L.; Almquist, Catherine B.; Briggs, Brandon R.

    2015-01-01

    Despite significant progress on iron reduction by thermophilic microorganisms, studies on their ability to reduce toxic metals are still limited, despite their common co-existence in high temperature environments (up to 70 °C). In this study, Methanothermobacter thermautotrophicus, an obligate thermophilic methanogen, was used to reduce hexavalent chromium. Experiments were conducted in a growth medium with H2/CO2 as substrate with various Cr6+ concentrations (0.2, 0.4, 1, 3, and 5 mM) in the form of potassium dichromate (K2Cr2O7). Time-course measurements of aqueous Cr6+ concentrations using 1,5-diphenylcarbazide colorimetric method showed complete reduction of the 0.2 and 0.4 mM Cr6+ solutions by this methanogen. However, much lower reduction extents of 43.6%, 13.0%, and 3.7% were observed at higher Cr6+ concentrations of 1, 3 and 5 mM, respectively. These lower extents of bioreduction suggest a toxic effect of aqueous Cr6+ to cells at this concentration range. At these higher Cr6+ concentrations, methanogenesis was inhibited and cell growth was impaired as evidenced by decreased total cellular protein production and live/dead cell ratio. Likewise, Cr6+ bioreduction rates decreased with increased initial concentrations of Cr6+ from 13.3 to 1.9 μM h-1. X-ray absorption near-edge structure (XANES) spectroscopy revealed a progressive reduction of soluble Cr6+ to insoluble Cr3+ precipitates, which was confirmed as amorphous chromium hydroxide by selected area electron diffraction pattern. However, a small fraction of reduced Cr occurred as aqueous Cr3+. Scanning and transmission electron microscope observations of M. thermautotrophicus cells after Cr6+ exposure suggest both extra- and intracellular chromium reduction mechanisms. Results of this study demonstrate the ability of M. thermautotrophicus cells to reduce toxic Cr6+ to less toxic Cr3+ and its potential application in metal bioremediation, especially at high temperature subsurface radioactive waste disposal

  3. Biological hydrogen production from biomass by thermophilic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Claassen, P.A.M.; Mars, A.E.; Budde, M.A.W.; Lai, M.; de Vrije, T. [Wageningen UR, Agrotechnology and Food Sciences Group (AFSG), Business Unit Biobased Products, P.O. Box 17, 6700 AA Wageningen, (Netherlands); van Niel, E.W.J. [Lund University, Applied microbiology, P.O. Box 124, 221 000 Lund, (Sweden)

    2006-07-01

    To meet the reduction of the emission of CO{sub 2} imposed by the Kyoto protocol, hydrogen should be produced from renewable primary energy. Besides the indirect production of hydrogen by electrolysis using electricity from renewable resources, such as sunlight, wind and hydropower, hydrogen can be directly produced from biomass. At present, there are two strategies for the production of hydrogen from biomass: the thermochemical technology, such as gasification, and the biotechnological approach using micro-organisms. Biological hydrogen production delivers clean hydrogen with an environmental-friendly technology and is very suitable for the conversion of wet biomass in small-scale applications, thus having a high chance of becoming an economically feasible technology. Many micro-organisms are able to produce hydrogen from mono- and disaccharides, starch and (hemi)cellulose under anaerobic conditions. The anaerobic production of hydrogen is a common phenomenon, occurring during the process of anaerobic digestion. Here, hydrogen producing micro-organisms are in syn-trophy with methanogenic bacteria which consume the hydrogen as soon as it is produced. In this way, hydrogen production remains obscure and methane is the end-product. By uncoupling hydrogen production from methane production, hydrogen becomes available for recovery and exploitation. This study describes the use of extreme thermophilic bacteria, selected because of a higher hydrogen production efficiency as compared to mesophilic bacteria, for the production of hydrogen from renewable resources. As feedstock energy crops like Miscanthus and Sorghum bicolor and waste streams like domestic organic waste, paper sludge and potato steam peels were used. The feedstock was pretreated and/or enzymatically hydrolyzed prior to fermentation to make a fermentable substrate. Hydrogen production by Caldicellulosiruptor saccharolyticus, Thermotoga elfii and T. neapolitana on all substrates was observed. Nutrient

  4. Biological hydrogen production from biomass by thermophilic bacteria

    International Nuclear Information System (INIS)

    To meet the reduction of the emission of CO2 imposed by the Kyoto protocol, hydrogen should be produced from renewable primary energy. Besides the indirect production of hydrogen by electrolysis using electricity from renewable resources, such as sunlight, wind and hydropower, hydrogen can be directly produced from biomass. At present, there are two strategies for the production of hydrogen from biomass: the thermochemical technology, such as gasification, and the biotechnological approach using micro-organisms. Biological hydrogen production delivers clean hydrogen with an environmental-friendly technology and is very suitable for the conversion of wet biomass in small-scale applications, thus having a high chance of becoming an economically feasible technology. Many micro-organisms are able to produce hydrogen from mono- and disaccharides, starch and (hemi)cellulose under anaerobic conditions. The anaerobic production of hydrogen is a common phenomenon, occurring during the process of anaerobic digestion. Here, hydrogen producing micro-organisms are in syn-trophy with methanogenic bacteria which consume the hydrogen as soon as it is produced. In this way, hydrogen production remains obscure and methane is the end-product. By uncoupling hydrogen production from methane production, hydrogen becomes available for recovery and exploitation. This study describes the use of extreme thermophilic bacteria, selected because of a higher hydrogen production efficiency as compared to mesophilic bacteria, for the production of hydrogen from renewable resources. As feedstock energy crops like Miscanthus and Sorghum bicolor and waste streams like domestic organic waste, paper sludge and potato steam peels were used. The feedstock was pretreated and/or enzymatically hydrolyzed prior to fermentation to make a fermentable substrate. Hydrogen production by Caldicellulosiruptor saccharolyticus, Thermotoga elfii and T. neapolitana on all substrates was observed. Nutrient requirements

  5. Effect of different redox mediators during thermophilic azo dye reduction by anaerobic granular sludge and comparative study between mesophilic (30C) and thermophilic (55C) treatments for decolourisation of textile wastewaters

    NARCIS (Netherlands)

    Bezerra Dos Santos, A.; Bisschops, I.A.E.; Cervantes, F.J.; Lier, van J.B.

    2004-01-01

    The impact of different redox mediators on colour removal of azo dye model compounds and textile wastewater by thermophilic anaerobic granular sludge (55 C) was investigated in batch assays. Additionally, a comparative study between mesophilic (30 C) and thermophilic (55 C) colour removal was perfor

  6. Enzymatic Screening and Molecular Characterization of Thermophilic Bacterial Strains Isolated from Hotspring of Tatopani, Bhurung, Nepal

    Directory of Open Access Journals (Sweden)

    Hriush Adhikari

    2015-09-01

    Full Text Available Background and Aim: In Nepal not much of study of Thermophilic area and Thermophiles have been done. Thermophilic bacteria are less studied but are important group of microorganisms due to their ability to produce industrially important enzymes. Methods: In this study, thermophilic bacteria were isolated from hot spring of Bhurung, Nepal. Wide range of bacteria that could grow at high temperatures and tolerate extreme temperature were characterized by morphology, biochemistry and sequencing of its 16S rRNA gene sequence. The isolates were screened for production of extracellular enzymes like protease, amylase, lipase, cellulase, caseinase, pectinase and xylanase activity. Phylogenetic tree construction and G+C content evaluation of the isolate was also studied. Results: 15 isolates with ability to tolerate high temperatures were identified as Bacillus sp. by morphology, biochemistry and sequencing of its 16S rRNA gene sequence. BLAST search analysis of the sequence was performed and result showed maximum identity (99% similarity with Bacillus licheniformis, Bacillus subtilis and Bacillus pumilus. Isolated strains exhibited considerable amount of extracellular exozymes activity. Phylogenetic analysis of the isolates revealed the relatedness among the species. The G+C content of each species was also evaluated and was found to be in range of 54.87 to 55.54%. Conclusion: The study of isolates confirmed that the isolated Bacillus sp. to be a true thermophile and could be a source of various thermostable exozymes which can be exploited for pharmaceutical and industrials applications. Much detailed study of the isolates can

  7. Effect of salinity and acidity on bioleaching activity of mesophilic and extremely thermophilic bacteria

    Institute of Scientific and Technical Information of China (English)

    H.DEVECI; M.A.JORDAN; N.POWELL; I.ALP

    2008-01-01

    The effects of bacterial strain,salinity and pH on the bioleaching of a complex ore using mesophilic and extremely thermophilic bacteria were investigated and the statistical analysis of the results was performed using ERGUN's test.The extreme thermophiles were shown to display superior kinetics of dissolution of zinc compared with the mesophiles as confirmed by the statistical analysis.Bioleaching performance of the extreme thermophiles is found to improve in response to the increase in acidity (pH from 2.0 to 1.0) whilst the activity of the mesophiles is adversely affected by decreasing pH.Statistical analysis of the bioleaching data indicates that the effect of pH is insignificant in the range of pH 1.0-1.2 for the extreme thermophiles and pH 1.4-2.0 for the mesophiles.Salinity is shown to have a suppressing effect on the mesophiles.However,the extreme thermophiles appear to be halophilic in character as they could operate efficiently under saline conditions (1%-4%C1- (w/v)).

  8. Community dynamics and glycoside hydrolase activities of thermophilic bacterial consortia adapted to switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, J.M.; Allgaier, M.; Miller, C.S.; Hazen, T.C.; VanderGheynst, J.S.; Hugenholtz, P.; Simmons, B.A.; Singer, S.W.

    2011-05-01

    Industrial-scale biofuel production requires robust enzymatic cocktails to produce fermentable sugars from lignocellulosic biomass. Thermophilic bacterial consortia are a potential source of cellulases and hemicellulases adapted to harsher reaction conditions than commercial fungal enzymes. Compost-derived microbial consortia were adapted to switchgrass at 60 C to develop thermophilic biomass-degrading consortia for detailed studies. Microbial community analysis using small-subunit rRNA gene amplicon pyrosequencing and short-read metagenomic sequencing demonstrated that thermophilic adaptation to switchgrass resulted in low-diversity bacterial consortia with a high abundance of bacteria related to thermophilic paenibacilli, Rhodothermus marinus, and Thermus thermophilus. At lower abundance, thermophilic Chloroflexi and an uncultivated lineage of the Gemmatimonadetes phylum were observed. Supernatants isolated from these consortia had high levels of xylanase and endoglucanase activities. Compared to commercial enzyme preparations, the endoglucanase enzymes had a higher thermotolerance and were more stable in the presence of 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), an ionic liquid used for biomass pretreatment. The supernatants were used to saccharify [C2mim][OAc]-pretreated switchgrass at elevated temperatures (up to 80 C), demonstrating that these consortia are an excellent source of enzymes for the development of enzymatic cocktails tailored to more extreme reaction conditions.

  9. Isobutanol production at elevated temperatures in thermophilic Geobacillus thermoglucosidasius.

    Science.gov (United States)

    Lin, Paul P; Rabe, Kersten S; Takasumi, Jennifer L; Kadisch, Marvin; Arnold, Frances H; Liao, James C

    2014-07-01

    The potential advantages of biological production of chemicals or fuels from biomass at high temperatures include reduced enzyme loading for cellulose degradation, decreased chance of contamination, and lower product separation cost. In general, high temperature production of compounds that are not native to the thermophilic hosts is limited by enzyme stability and the lack of suitable expression systems. Further complications can arise when the pathway includes a volatile intermediate. Here we report the engineering of Geobacillus thermoglucosidasius to produce isobutanol at 50°C. We prospected various enzymes in the isobutanol synthesis pathway and characterized their thermostabilities. We also constructed an expression system based on the lactate dehydrogenase promoter from Geobacillus thermodenitrificans. With the best enzyme combination and the expression system, 3.3g/l of isobutanol was produced from glucose and 0.6g/l of isobutanol from cellobiose in G. thermoglucosidasius within 48h at 50°C. This is the first demonstration of isobutanol production in recombinant bacteria at an elevated temperature.

  10. Biogeography of thermophilic phototrophic bacteria belonging to Roseiflexus genus.

    Science.gov (United States)

    Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2016-03-01

    Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range.

  11. Isolation and characterization of novel thermophilic lipase-secreting bacteria

    Directory of Open Access Journals (Sweden)

    Mohammed Rabbani

    2013-12-01

    Full Text Available The purpose of the present study was to screen and identify the lipase-producing microorganisms from various regions of Iran. Samples collected from hot spring, Persian Gulf, desert area and oil-contaminated soil, were analyzed for thermophilic extracellular-lipase producing organisms. Six strains with high activity on rhodamine B plates were selected for chemical identification and further study. Among these isolated bacteria, four strains show higher activity in pH-Stat method at 55 °C. These strains were identified by PCR amplification of 16s rRNA genes using universal primers. Fermentation increased the activity up to 50%. The growth medium, designed for lipase production, increased the activity up to 4.55 folds. The crude supernatant of ZR-5 after fermentation and separation the cells, was lyophilized and the activity was measured. Total activity of this strain was 12 kU/g that shows its potential for industrial uses. Further study is required for purification of enzyme and calculation its specific activity. Immobilization is another approach should be considered.

  12. Isolation and characterization of novel thermophilic lipase-secreting bacteria.

    Science.gov (United States)

    Rabbani, Mohammed; Bagherinejad, Mohammad Reza; Sadeghi, Hamid MirMohammad; Shariat, Ziaedin Samsam; Etemadifar, Zahra; Moazen, Fatemeh; Rahbari, Manizheh; Mafakher, Ladan; Zaghian, Saeideh

    2013-12-01

    The purpose of the present study was to screen and identify the lipase-producing microorganisms from various regions of Iran. Samples collected from hot spring, Persian Gulf, desert area and oil-contaminated soil, were analyzed for thermophilic extracellular-lipase producing organisms. Six strains with high activity on rhodamine B plates were selected for chemical identification and further study. Among these isolated bacteria, four strains show higher activity in pH-Stat method at 55 °C. These strains were identified by PCR amplification of 16s rRNA genes using universal primers. Fermentation increased the activity up to 50%. The growth medium, designed for lipase production, increased the activity up to 4.55 folds. The crude supernatant of ZR-5 after fermentation and separation the cells, was lyophilized and the activity was measured. Total activity of this strain was 12 kU/g that shows its potential for industrial uses. Further study is required for purification of enzyme and calculation its specific activity. Immobilization is another approach should be considered. PMID:24688500

  13. Single gene insertion drives bioalcohol production by a thermophilic archaeon

    Energy Technology Data Exchange (ETDEWEB)

    Basen, M; Schut, GJ; Nguyen, DM; Lipscomb, GL; Benn, RA; Prybol, CJ; Vaccaro, BJ; Poole, FL; Kelly, RM; Adams, MWW

    2014-12-09

    Bioethanol production is achieved by only two metabolic pathways and only at moderate temperatures. Herein a fundamentally different synthetic pathway for bioalcohol production at 70 degrees C was constructed by insertion of the gene for bacterial alcohol dehydrogenase (AdhA) into the archaeon Pyrococcus furiosus. The engineered strain converted glucose to ethanol via acetate and acetaldehyde, catalyzed by the host-encoded aldehyde ferredoxin oxidoreductase (AOR) and heterologously expressed AdhA, in an energy-conserving, redox-balanced pathway. Furthermore, the AOR/AdhA pathway also converted exogenously added aliphatic and aromatic carboxylic acids to the corresponding alcohol using glucose, pyruvate, and/or hydrogen as the source of reductant. By heterologous coexpression of a membrane-bound carbon monoxide dehydrogenase, CO was used as a reductant for converting carboxylic acids to alcohols. Redirecting the fermentative metabolism of P. furiosus through strategic insertion of foreign genes creates unprecedented opportunities for thermophilic bioalcohol production. Moreover, the AOR/AdhA pathway is a potentially game-changing strategy for syngas fermentation, especially in combination with carbon chain elongation pathways.

  14. Biogeography of thermophilic phototrophic bacteria belonging to Roseiflexus genus.

    Science.gov (United States)

    Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2016-03-01

    Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range. PMID:26826142

  15. Kinetics of inactivation of indicator pathogens during thermophilic anaerobic digestion.

    Science.gov (United States)

    Popat, Sudeep C; Yates, Marylynn V; Deshusses, Marc A

    2010-12-01

    Thermophilic anaerobic sludge digestion is a promising process to divert waste to beneficial use, but an important question is the required temperature and holding time to achieve a given degree of pathogen inactivation. In this study, the kinetics of inactivation of Ascaris suum and vaccine strain poliovirus type 1 (PVS-1), selected as indicators for helminth ova and enteric viruses respectively, were determined during anaerobic digestion at temperatures ranging from 51 to 56 °C. Inactivation of both indicator organisms was fast with greater than two log reductions achieved within 2 h for A. suum and three log reductions for PVS-1, suggesting that the current U.S. regulations are largely conservative. The first-order inactivation rate constants k followed Arrhenius relationship with activation energies of 105 and 39 KJ mol(-1) for A. suum and PVS-1, respectively indicating that A. suum was more sensitive to temperature. Although inactivation was fast, the presence of compounds in the sludge that are known to be protective of pathogen inactivation was observed, suggesting that composition-dependent time-temperature relationships are necessary. PMID:20692678

  16. Characterization of thermophilic consortia from two souring oil reservoirs.

    Science.gov (United States)

    Mueller, R F; Nielsen, P H

    1996-09-01

    The microbial consortia from produced water at two different oil fields in Alaska (Kuparuk) and the North Sea (Ninian) were investigated for sulfate-reducing and methanogenic activity over a range of temperatures and for a variety of substrates. The consortia were sampled on site, and samples were either incubated on site at 60(deg)C with various substrates or frozen for later incubation and analyses. Temperature influenced the rates of sulfate reduction, hydrogen sulfide production, and substrate oxidation, as well as the cell morphology. The highest rates of sulfate reduction and substrate oxidation were found between 50 and 60(deg)C. Formate and n-butyrate were the most favorable electron donors at any tested temperature. Acetate was utilized at 35(deg)C but not at 50 or 70(deg)C and was produced at 60(deg)C. This indicates that the high levels of acetate found in produced water from souring oil formations are due mainly to an incomplete oxidation of volatile fatty acids to acetate. The cell size distribution of the microbial consortium indicated a nonuniform microbial composition in the original sample from the Kuparuk field. At different temperatures, different microbial morphologies and physiologies were observed. Methane-producing activity at thermophilic temperatures (60(deg)C) was found only for the Kuparuk consortium when hydrogen and carbon dioxide were present. No methane production from acetate was observed. Suppression of methanogenic activity in the presence of sulfate indicated a competition with sulfate-reducing bacteria for hydrogen.

  17. Involvement of thermophilic archaea in the biocorrosion of oil pipelines.

    Science.gov (United States)

    Davidova, Irene A; Duncan, Kathleen E; Perez-Ibarra, B Monica; Suflita, Joseph M

    2012-07-01

    Two thermophilic archaea, strain PK and strain MG, were isolated from a culture enriched at 80°C from the inner surface material of a hot oil pipeline. Strain PK could ferment complex organic nitrogen sources (e.g. yeast extract, peptone, tryptone) and was able to reduce elemental sulfur (S°), Fe(3+) and Mn(4+) . Phylogenetic analysis revealed that the organism belonged to the order Thermococcales. Incubations of this strain with elemental iron (Fe°) resulted in the abiotic formation of ferrous iron and the accumulation of volatile fatty acids during yeast extract fermentation. The other isolate, strain MG, was a H(2) :CO(2) -utilizing methanogen, phylogenetically affiliated with the genus Methanothermobacter family. Co-cultures of the strains grew as aggregates that produced CH(4) without exogenous H(2) amendment. The co-culture produced the same suite but greater concentrations of fatty acids from yeast extract than did strain PK alone. Thus, the physiological characteristics of organisms both alone and in combination could conceivably contribute to pipeline corrosion. The Thermococcus strain PK could reduce elemental sulfur to sulfide, produce fatty acids and reduce ferric iron. The hydrogenotrophic methanogen strain MG enhanced fatty acid production by fermentative organisms but could not couple the dissolution Fe° with the consumption of water-derived H(2) like other methanogens.

  18. Thermophilic hydrogen fermentation from Korean rice straw by Thermotoga neapolitana

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Tam-Anh D.; Kim, Kyoung-Rok; Sim, Sang Jun [Department of Chemical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Mi Sun [Bioenergy Research Center, Korea Institute of Energy Research, Daejeon 305-343 (Korea, Republic of)

    2010-12-15

    Rice straw, a low-cost lignocellulosic biomass was used as feedstock for thermophilic hydrogen fermentation by Thermotoga neapolitana. Hydrogen production, the growth and cellulose digestibility of the hyperthermophile in batch mode from untreated as well as chemically pretreated (ammonia and dilute sulfuric acid) Korean rice straws were investigated. Pretreatment method using combination of 10% ammonia and 1.0% dilute sulfuric acid was developed to increase the digestibility of rice straw for the hyperthermophilic H{sub 2} fermentation and to decrease the time consumption. In a typical fermentation using raw rice straw, 29% of the substrate was digested and 2.3 mmol H{sub 2}/g straw of hydrogen yield was consistently obtained. Compared with the pretreatments using only ammonia or dilute sulfuric acid, the combined pretreatment method using both chemical agents significantly increases the digestibility of rice straw with 85.4% of substrate consumption. H{sub 2} production on rice straw from this combined pretreatment showed the highest yield (2.7 mmol H{sub 2}/g straw) and the highest sugar conversions (72.9% of glucose and 95.7% of xylose). (author)

  19. Modeling temperature variations in a pilot plant thermophilic anaerobic digester.

    Science.gov (United States)

    Valle-Guadarrama, Salvador; Espinosa-Solares, Teodoro; López-Cruz, Irineo L; Domaschko, Max

    2011-05-01

    A model that predicts temperature changes in a pilot plant thermophilic anaerobic digester was developed based on fundamental thermodynamic laws. The methodology utilized two simulation strategies. In the first, model equations were solved through a searching routine based on a minimal square optimization criterion, from which the overall heat transfer coefficient values, for both biodigester and heat exchanger, were determined. In the second, the simulation was performed with variable values of these overall coefficients. The prediction with both strategies allowed reproducing experimental data within 5% of the temperature span permitted in the equipment by the system control, which validated the model. The temperature variation was affected by the heterogeneity of the feeding and extraction processes, by the heterogeneity of the digestate recirculation through the heating system and by the lack of a perfect mixing inside the biodigester tank. The use of variable overall heat transfer coefficients improved the temperature change prediction and reduced the effect of a non-ideal performance of the pilot plant modeled.

  20. Selecting the best inoculation for anaerobic thermophilic treatment in sewage plants; Seleccion de inoculo para el tratamiento anaerobio termofilico de lodos de depuradora

    Energy Technology Data Exchange (ETDEWEB)

    Riau, V.; Rubia, M. A. de la; Forster, T.; Perez, M.

    2009-07-01

    The objective of the present work is to propose a suitable method to obtain an thermophilic inoculum source able for the anaerobic thermophilic digestion of sludge raw. Also, the acclimatization period to the temperature and the substrate is study as well as the thermophilic process at different solids retention of solids is analyzed. (Author) 18 refs.

  1. Complete genome sequence of Geobacillus thermoglucosidans TNO-09.020, a thermophilic sporeformer associated with a dairy-processing environment

    NARCIS (Netherlands)

    Zhao, Y.; Caspers, M.P.; Abee, T.; Siezen, R.J.; Kort, R.

    2012-01-01

    Thermophilic spore-forming bacteria are a common cause of contamination in dairy products. We isolated the thermophilic strain Geobacillus thermoglucosidans TNO-09.020 from a milk processing plant and report the complete genome of a dairy plant isolate consisting of a single chromosome of 3.75 Mb.

  2. Complete Genome Sequence of Geobacillus thermoglucosidans TNO-09.020, a Thermophilic Sporeformer Associated with a Dairy-Processing Environment.

    NARCIS (Netherlands)

    Zhao, Y.; Caspers, M.P.; Abee, T.; Siezen, R.J.; Kort, R.

    2012-01-01

    Thermophilic spore-forming bacteria are a common cause of contamination in dairy products. We isolated the thermophilic strain Geobacillus thermoglucosidans TNO-09.020 from a milk processing plant and report the complete genome of a dairy plant isolate consisting of a single chromosome of 3.75 Mb.

  3. Complete genome sequence of Geobacillus thermoglucosidans TNO-09.020, a thermophilic sporeformer associated with a dairy-processing environment

    NARCIS (Netherlands)

    Zhao, Y.; Caspers, M.P.; Abee, T.; Siezen, R.J.; Kort, R.

    2012-01-01

    Thermophilic spore-forming bacteria are a common cause of contamination in dairy products. We isolated the thermophilic strain Geobacillus thermoglucosidans TNO-09.020 from a milk processing plant and report the complete genome of a dairy plant isolate consisting of a single chromosome of 3.75 Mb. ©

  4. Group-specific 16S rRNA-targeted oligonucleotide probes to identify thermophilic bacteria in marine hydrothermal vents

    NARCIS (Netherlands)

    Harmsen, HJM; Prieur, D; Jeanthon, C

    1997-01-01

    Four 16S rRNA-targeted oligonucleotide probes were designed for the detection of thermophilic members of the domain Bacteria known to thrive in marine hydrothermal systems, We developed and characterized probes encompassing most of the thermophilic members of the genus Bacillus, most species of the

  5. Effect of NaCl on thermophilic (55°C) methanol degradation in sulfate reducing granular sludge reactors

    NARCIS (Netherlands)

    Vallero, M.V.G.; Hulshoff Pol, L.W.; Lettinga, G.; Lens, P.N.L.

    2003-01-01

    The effect of NaCl on thermophilic (55degreesC) methanol conversion in the presence of excess of sulfate (COD/SO42-=0.5) was investigated in two 6.5L lab-scale upflow anaerobic sludge bed reactors inoculated with granular sludge previously not adapted to NaCl
    The effect of NaCl on thermophilic (

  6. Methanol coneversion by a novel thermophilic homoacetogenic bacterium Moorella mulderi sp.nov. isolated from a bioreactor

    NARCIS (Netherlands)

    Balk, M.; Weijma, J.; Friedrich, M.W.; Stams, A.J.M.

    2003-01-01

    A thermophilic, anaerobic, spore-forming bacterium (strain TMS) was isolated from a thermophilic bioreactor operated at 65 degreesC with methanol as the energy source. Cells were gram-positive straight rods, 0.4-0.6 mum x 2-8 mum, growing as single cells or in pairs. The temperature range for growth

  7. Insight into structure and assembly of the nuclear pore complex by utilizing the genome of a eukaryotic thermophile

    DEFF Research Database (Denmark)

    Amlacher, Stefan; Sarges, Phillip; Flemming, Dirk;

    2011-01-01

    Despite decades of research, the structure and assembly of the nuclear pore complex (NPC), which is composed of ~30 nucleoporins (Nups), remain elusive. Here, we report the genome of the thermophilic fungus Chaetomium thermophilum (ct) and identify the complete repertoire of Nups therein. The the...... of a thermophilic eukaryote for studying complex molecular machines....

  8. Dominant ectosymbiotic bacteria of cellulolytic protists in the termite gut also have the potential to digest lignocellulose.

    Science.gov (United States)

    Yuki, Masahiro; Kuwahara, Hirokazu; Shintani, Masaki; Izawa, Kazuki; Sato, Tomoyuki; Starns, David; Hongoh, Yuichi; Ohkuma, Moriya

    2015-12-01

    Wood-feeding lower termites harbour symbiotic gut protists that support the termite nutritionally by degrading recalcitrant lignocellulose. These protists themselves host specific endo- and ectosymbiotic bacteria, functions of which remain largely unknown. Here, we present draft genomes of a dominant, uncultured ectosymbiont belonging to the order Bacteroidales, 'Candidatus Symbiothrix dinenymphae', which colonizes the cell surface of the cellulolytic gut protists Dinenympha spp. We analysed four single-cell genomes of Ca. S. dinenymphae, the highest genome completeness was estimated to be 81.6-82.3% with a predicted genome size of 4.28-4.31 Mb. The genome retains genes encoding large parts of the amino acid, cofactor and nucleotide biosynthetic pathways. In addition, the genome contains genes encoding various glycoside hydrolases such as endoglucanases and hemicellulases. The genome indicates that Ca. S. dinenymphae ferments lignocellulose-derived monosaccharides to acetate, a major carbon and energy source of the host termite. We suggest that the ectosymbiont digests lignocellulose and provides nutrients to the host termites, and hypothesize that the hydrolytic activity might also function as a pretreatment for the host protist to effectively decompose the crystalline cellulose components. PMID:26079531

  9. Development of a real-time PCR assay for monitoring anaerobic fungal and cellulolytic bacterial populations within the rumen.

    Science.gov (United States)

    Denman, Stuart E; McSweeney, Christopher S

    2006-12-01

    Traditional methods for enumerating and identifying microbial populations within the rumen can be time consuming and cumbersome. Methods that involve culturing and microscopy can also be inconclusive, particularly when studying anaerobic rumen fungi. A real-time PCR SYBR Green assay, using PCR primers to target total rumen fungi and the cellulolytic bacteria Ruminococcus flavefaciens and Fibrobacter succinogenes, is described, including design and validation. The DNA and crude protein contents with respect to the fungal biomass of both polycentric and monocentric fungal isolates were investigated across the fungal growth stages to aid in standard curve generation. The primer sets used were found to be target specific with no detectable cross-reactivity. Subsequently, the real-time PCR assay was employed in a study to detect these populations within cattle rumen. The anaerobic fungal target was observed to increase 3.6-fold from 0 to 12 h after feeding. The results also indicated a 5.4-fold increase in F. succinogenes target between 0 and 12 h after feeding, whereas R. flavefaciens was observed to maintain more or less consistent levels. This is the first report of a real-time PCR assay to estimate the rumen anaerobic fungal population. PMID:17117998

  10. ISOLATION AND PHYSICO-CHEMICAL CHARACTERIZATION OF EXTRACELLULAR LIGNO-CELLULOLYTIC ENZYMES OF PLEUROTUS PULMONARIUS IN SUBMERGED FERMENTATION

    Directory of Open Access Journals (Sweden)

    Nirmalendu Das

    2015-07-01

    Full Text Available Pleurotus pulmonarius, a member of oyster mushroom can produced lignocellulosic enzymes laccase, peroxidise and cellulase in liquid potato-dextrose medium in submerged stationary condition. The lignocellulolytic activities were assayed using the extracellular culture filtrate which was partially purified using 0- 80% ammonium sulphate saturation. Different physico-chemical studies were performed using the partially purified culture filtrate. The fungus produced more laccase and peroxidase than the cellulase. The optimum laccase production was found on 17th day whereas cellulase & peroxidase productions were found on 9th& 10th day, respectively. Km of laccase is 4.1mM against guaiacol and 1.25 mM against o-dianisidine whereas Km of peroxidase was 0.72mM and cellulase was 0.06 mM. Optimum pH of laccase was 6.0 but for peroxidase and cellulase it was 7.0. The temperature optima of cellulase (50?C was more than laccase (40?C and peroxidase (30?C. All the lignocellulosic enzymes showed a wide range of temperature and pH stabilities. Laccase and peroxidase were fully inhibited by NaCl but it was not so effective against cellulase. P. pulmonarius showed higher ligninolytic (Laccase and peroxidase activity than cellulolytic (cellulase activity. The lignocellulosic enzymes isolated from submerged fermentation of P. pulmonarius might be industrially significant as they showed a wide range of temperature and pH stabilities.

  11. Characteristics of Recombinant Phytase (rSt-Phy) of the Thermophilic mold Sporotrichum thermophile and its applicability in dephytinizing foods.

    Science.gov (United States)

    Ranjan, Bibhuti; Singh, Bijender; Satyanarayana, T

    2015-12-01

    Sporotrichum thermophile produces very low titres of phytase (St-Phy) extracellularly, which is acidstable, thermostable, and protease insensitive with broad substrate specificity, and therefore, the gene encoding phytase (St-Phy) has been cloned and expressed in E. coli. The purified recombinant phytase (rSt-Phy) has the molecular mass of 55 kDa with Km and Vmax (calcium phytate), kcat and kcat/Km of 0.143 mM, 185.05 nmoles mg(-1)  s(-1), 5.1 × 10(3) s(-1), and 3.5 × 10(7) M(-1) s(-1), respectively. Mg(2+) and Ba(2+) display slight stimulatory effect on the enzyme, while it is inhibited by other ions to a varied extent. The enzyme is also inhibited by chaotropic agents (guanidinium hydrochloride, potassium iodide, and urea), Woodward's reagent K, and 2,3-butanedione but resistant to both pepsin and trypsin. The rSt-Phy is useful in dephytinization of tandoori and naan (unleavened flat Indian breads), and bread, liberating soluble inorganic phosphate that mitigates anti-nutrient effects of phytic acid. PMID:26433599

  12. Influence of temperature fluctuation on thermophilic anaerobic digestion of municipal organic solid waste

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A laboratory-scale experiment was carried out to assess the influence of temperature fluctuation on thermophilic anaerobic digestion of municipal organic solid waste (MOSW). Heating failure was simulated by decreasing temperature suddenly from 55 ℃ to 20 ℃ suddenly; 2 h time is needed for temperature decrease and recovery. Under the conditions ofS.0 g/(L·d) and 15 d respectively for MOSW load and retention time, following results were noted: (1) biogas production almost stopped and VFA (volatile fatty acid) accumulated rapidly, accompanied by pH decrease; (2) with low temperature (20 ℃) duration of 1, 5, 12 and 24 h, it took 3, 11, 56 and 72 h for the thermophilic anaerobic digestion system to reproduce methane after temperature fluctuation;(3) the longer the low temperature interval lasted, the more the methanogenic bacteria would decay; hydrolysis, acidification and methanogenesis were all influenced by temperature fluctuation; (4) the thermophilic microorganisms were highly resilient to temperature fluctuation.

  13. Over-expression of carboxypeptidase of extreme thermophile pyrococcus furiosus in escherichia coli

    International Nuclear Information System (INIS)

    Thermophiles and extreme thermophiles are potential source of thermostable proteases for economical application. This study deals with cloning and over-expression of a carboxypeptidase (CBP) from the extreme thermophile archaeon Pyrococcus furiosus in E. coli. Using the forward and the reverse primers designed according to the putative CBP gene sequence analysed from the published genome sequence of P. furiosus, 1.5 kb fragment of CBP gene was PCR amplified. After TA-cloning in pTZ57R/T vector, the gene was ligated into pET-22b(+) and the recombinant plasmid thus obtained was used to transform E. coli BL21 (DE3)RIPL. On induction with IPTG for 6-8 hours CBP was expressed up to 30% of the total cell proteins. The enzyme, however, was expressed in an insoluble form which was refolded to an active state by treatment with urea. (author)

  14. Thermophilic Sulfate Reduction in Hydrothermal Sediment of Lake Tanganyika, East-Africa

    DEFF Research Database (Denmark)

    ELSGAARD, L.; PRIEUR, D.; MUKWAYA, GM;

    1994-01-01

    In environments with temperatures above 60 degrees C, thermophilic prokaryotes are the only metabolically active life-forms. By using the (SO42-)-S-35 tracer technique, we studied the activity of sulfate-reducing microorganisms (SRM) in hot sediment from a hydrothermal vent site in the northern...... population of SRM in the hydrothermal sediment. Thermophilic sulfate reduction had a pH optimum of about 7 and was completely inhibited at pH 8.8 to 9.2. SRM could be enriched from hydrothermal chimney and sediment samples at 60 and 75 degrees C. In lactate-grown enrichments, sulfide production occurred...... at up to 70 and 75 degrees C, with optima at 63 and 71 degrees C, respectively. Several sporulating thermophilic enrichments were morphologically similar to Desulfotomaculum spp. Dissimilatory sulfate reduction in the studied hydrothermal area of Lake Tanganyika apparently has an upper temperature limit...

  15. Metagenomics of Thermophiles with a Focus on Discovery of Novel Thermozymes

    Science.gov (United States)

    DeCastro, María-Eugenia; Rodríguez-Belmonte, Esther; González-Siso, María-Isabel

    2016-01-01

    Microbial populations living in environments with temperatures above 50°C (thermophiles) have been widely studied, increasing our knowledge in the composition and function of these ecological communities. Since these populations express a broad number of heat-resistant enzymes (thermozymes), they also represent an important source for novel biocatalysts that can be potentially used in industrial processes. The integrated study of the whole-community DNA from an environment, known as metagenomics, coupled with the development of next generation sequencing (NGS) technologies, has allowed the generation of large amounts of data from thermophiles. In this review, we summarize the main approaches commonly utilized for assessing the taxonomic and functional diversity of thermophiles through metagenomics, including several bioinformatics tools and some metagenome-derived methods to isolate their thermozymes. PMID:27729905

  16. Biogas production and methanogenic archaeal community in mesophilic and thermophilic anaerobic co-digestion processes.

    Science.gov (United States)

    Yu, D; Kurola, J M; Lähde, K; Kymäläinen, M; Sinkkonen, A; Romantschuk, M

    2014-10-01

    Over 258 Mt of solid waste are generated annually in Europe, a large fraction of which is biowaste. Sewage sludge is another major waste fraction. In this study, biowaste and sewage sludge were co-digested in an anaerobic digestion reactor (30% and 70% of total wet weight, respectively). The purpose was to investigate the biogas production and methanogenic archaeal community composition in the anaerobic digestion reactor under meso- (35-37 °C) and thermophilic (55-57 °C) processes and an increasing organic loading rate (OLR, 1-10 kg VS m(-3) d(-1)), and also to find a feasible compromise between waste treatment capacity and biogas production without causing process instability. In summary, more biogas was produced with all OLRs by the thermophilic process. Both processes showed a limited diversity of the methanogenic archaeal community which was dominated by Methanobacteriales and Methanosarcinales (e.g. Methanosarcina) in both meso- and thermophilic processes. Methanothermobacter was detected as an additional dominant genus in the thermophilic process. In addition to operating temperatures, the OLRs, the acetate concentration, and the presence of key substrates like propionate also affected the methanogenic archaeal community composition. A bacterial cell count 6.25 times higher than archaeal cell count was observed throughout the thermophilic process, while the cell count ratio varied between 0.2 and 8.5 in the mesophilic process. This suggests that the thermophilic process is more stable, but also that the relative abundance between bacteria and archaea can vary without seriously affecting biogas production.

  17. Interconversion of functional motions between mesophilic and thermophilic adenylate kinases.

    Directory of Open Access Journals (Sweden)

    Michael D Daily

    2011-07-01

    Full Text Available Dynamic properties are functionally important in many proteins, including the enzyme adenylate kinase (AK, for which the open/closed transition limits the rate of catalytic turnover. Here, we compare our previously published coarse-grained (double-well Gō simulation of mesophilic AK from E. coli (AKmeso to simulations of thermophilic AK from Aquifex aeolicus (AKthermo. In AKthermo, as with AKmeso, the LID domain prefers to close before the NMP domain in the presence of ligand, but LID rigid-body flexibility in the open (O ensemble decreases significantly. Backbone foldedness in O and/or transition state (TS ensembles increases significantly relative to AKmeso in some interdomain backbone hinges and within LID. In contact space, the TS of AKthermo has fewer contacts at the CORE-LID interface but a stronger contact network surrounding the CORE-NMP interface than the TS of AKmeso. A "heated" simulation of AKthermo at 375K slightly increases LID rigid-body flexibility in accordance with the "corresponding states" hypothesis. Furthermore, while computational mutation of 7 prolines in AKthermo to their AKmeso counterparts produces similar small perturbations, mutation of these sites, especially positions 8 and 155, to glycine is required to achieve LID rigid-body flexibility and hinge flexibilities comparable to AKmeso. Mutating the 7 sites to proline in AKmeso reduces some hinges' flexibilities, especially hinge 2, but does not reduce LID rigid-body flexibility, suggesting that these two types of motion are decoupled in AKmeso. In conclusion, our results suggest that hinge flexibility and global functional motions alike are correlated with but not exclusively determined by the hinge residues. This mutational framework can inform the rational design of functionally important flexibility and allostery in other proteins toward engineering novel biochemical pathways.

  18. Interaction of gaseous aromatic and aliphatic compounds in thermophilic biofilters.

    Science.gov (United States)

    Hu, Qing-yuan; Wang, Can

    2015-12-30

    Two thermophilic biofilters were applied in treating a mixture of gaseous aromatic (benzene) and aliphatic compounds (hexane) to evaluate the interaction of the compounds. The performance of the biofilters was investigated in terms of removal efficiencies, elimination capacity, kinetic analysis, interaction indices, and microbial metabolic characteristics. Results showed that the removal performance of benzene was unaffected by the addition of hexane. The removal efficiencies of benzene were maintained at approximately 80% and the biodegradation rate constant was maintained at 120 h(-1). However, the removal efficiencies of hexane decreased significantly from 60% to 20% and the biodegradation rate constant exhibited a distinct decrease from 93.59 h(-1) to 56.32 h(-1). The interaction index of benzene with the addition of hexane was -0.029, which indicated that hexane had little effect on the degradation of benzene. By contrast, the interaction index of hexane by benzene was -0.557, which showed that benzene inhibited the degradation of hexane significantly. Similar conclusions were obtained about the substrate utilization. Moreover, the utilization degree of carbon sources and the microbial metabolic activities in the biofilter treating hexane were significantly improved with the addition of benzene, whereas the addition of hexane had a slight effect on the microbial communities in the biofilter treating benzene. Conclusions could be obtained that when mixtures of benzene and hexane were treated using biofilters, the degradation of benzene, which was more easily degradable, was dominant and unaffected; whereas the degradation of hexane, which was less easily degradable, was inhibited because of the changing of microbes.

  19. Isolation and identification of the thermophilic alkaline desulphuricant strain

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A desulfurization strain that belongs to the thermophilic alkaline desulphuricant is designated as strain GDJ-3 and isolated from Inner Mongolia, China. The colony of the strain shows tiny, yellow, or white-yellow, and it becomes henna with the protracting of cultivated time. The cells are bacilliform (0.3 -0.6 × 1.0-1.2 μm), motive, and Gram negative. The strain GDJ-3 is able to utilize respectively the thiosulphate, sulfate, sulfite, or sulfide as sulfur source, utilize the carbon dioxide as the carbon source, and utilize the ammonium or nitrate as the nitrogen source. According to GenBank data, 16s RNA results of GDJ-3 are in good agreement with Alpha proteobacterrium sp. (97%) and Ochrobactrum sp. (98%). For GDJ-3, the optimum growth temperature is at 45℃, the optimum pH is at 8.5-8.8, and the optimum rocking speed of sorting table is at 150 r/min. Under the optimum culture condition, the cells of the strain can live for about 18 h. In the desulfurization solution, which is prepared according to the composition of DDS solution, the objectionable constituents of sodium thiosulphate and sodium sulfide were added factitiously, and the bacterial cell concentration was set at 107/mL. After the regeneration of the above desulfurization solution by the strain cells, the concentration of sodium thiosulphate was decreased by 14.75 g/L (percentage loss of content 13.21%), the concentration of sodium sulfide was decreased by 0.76 g/L (percentage loss of content 87.36%) in the desulfurization solution in 9.5 hours, and sulfur appeared. Maybe, this kind of strain can be used as the regeneration’s bacterial source of DDS solution.

  20. Isolation of cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and molecular comparison with dairy-related Lactobacillus helveticus strains

    DEFF Research Database (Denmark)

    Jensen, Marie Elisabeth Penderup; Ardö, Ylva Margareta; Vogensen, Finn Kvist

    2009-01-01

    Aims: To isolate cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and compare them with dairy-related Lactobacillus helveticus strains using molecular typing methods. Methods and Results: The number of thermophilic bacteria in seven commercial cheeses manufac...... and thermophilic adjunct cultures by using an enumeration step. Significance and Impact of the Study: Isolation of cultivable thermophilic bacteria from ripened cheeses made with mesophilic starters offers an original source for new dairy-relevant cultures.......Aims: To isolate cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and compare them with dairy-related Lactobacillus helveticus strains using molecular typing methods. Methods and Results: The number of thermophilic bacteria in seven commercial cheeses...... manufactured with mesophilic starters was estimated to be enumeration step in the isolation method made it possible to isolate one thermophilic strain from each of five of seven cheeses. Comparing repetitive sequence PCR (rep-PCR) profiles of the isolates with dairy...

  1. Enzymatic activity of the cellulolytic complex produced by Trichoderma reesei. Enzymatic hydrolysis of cellulose; Actividad enzimatica del complejo celulolitico producido por Trichoderma reesei. Hidrolisis enzimatica de la celulosa

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsel, M.; Negro, M. J.; Saez, R.; Martin, C.

    1986-07-01

    The enzymatic activity characterization of the cellulolytic complex obtained from Trichoderma reesei QM 9414 and the influence of the enzymatic hydrolysis conditions on the hydrolysis yield are studied. Pure cellulose and native or alkali pretreated biomass Onopordum nervosum have been used as substrates. The values of pH, temperature, substrate concentration and enzyme-substrate ratio for the optimum activity of that complex, evaluated as glucose and reducing sugars production, have been selected. Previous studies on enzymatic hydrolysis of 0. nervosum have shown a remarkable effect of the alkaline pretreatments on the final hydrolysis yield. (Author) 10 refs.

  2. Dissecting and engineering metabolic and regulatory networks of thermophilic bacteria for biofuel production.

    Science.gov (United States)

    Lin, Lu; Xu, Jian

    2013-11-01

    Interest in thermophilic bacteria as live-cell catalysts in biofuel and biochemical industry has surged in recent years, due to their tolerance of high temperature and wide spectrum of carbon-sources that include cellulose. However their direct employment as microbial cellular factories in the highly demanding industrial conditions has been hindered by uncompetitive biofuel productivity, relatively low tolerance to solvent and osmic stresses, and limitation in genome engineering tools. In this work we review recent advances in dissecting and engineering the metabolic and regulatory networks of thermophilic bacteria for improving the traits of key interest in biofuel industry: cellulose degradation, pentose-hexose co-utilization, and tolerance of thermal, osmotic, and solvent stresses. Moreover, new technologies enabling more efficient genetic engineering of thermophiles were discussed, such as improved electroporation, ultrasound-mediated DNA delivery, as well as thermo-stable plasmids and functional selection systems. Expanded applications of such technological advancements in thermophilic microbes promise to substantiate a synthetic biology perspective, where functional parts, module, chassis, cells and consortia were modularly designed and rationally assembled for the many missions at industry and nature that demand the extraordinary talents of these extremophiles.

  3. Draft Genome Sequence of a Thermophilic Desulfurization Bacterium, Geobacillus thermoglucosidasius Strain W-2

    Science.gov (United States)

    Zhu, Lin; Li, Mingchang; Guo, Shuyi

    2016-01-01

    Geobacillus thermoglucosidasius strain W-2 is a thermophilic bacterium isolated from a deep-subsurface oil reservoir in northern China, which is capable of degrading organosulfur compounds. Here, we report the draft genome sequence of G. thermoglucosidasius strain W-2, which may help to elucidate the genetic basis of biodegradation of organosulfur pollutants under heated conditions. PMID:27491977

  4. Cloning, sequencing, and sequence analysis of two novel plasmids from the thermophilic anaerobic bacterium Anaerocellum thermophilum

    DEFF Research Database (Denmark)

    Clausen, Anders; Mikkelsen, Marie Just; Schrøder, I.;

    2004-01-01

    The nucleotide sequence of two novel plasmids isolated from the extreme thermophilic anaerobic bacterium Anaerocellum thermophilum DSM6725 (A. thermophilum), growing optimally at 70degreesC, has been determined. pBAS2 was found to be a 3653 bp plasmid with a GC content of 43%, and the sequence...

  5. Thermaerobacter litoralis sp. nov., a strictly aerobic and thermophilic bacterium isolated from a coastal hydrothermal field

    DEFF Research Database (Denmark)

    Tanaka, Reiji; Kawaichi, Satoshi; Nishimura, Hiroshi;

    2006-01-01

    A novel thermophilic bacterium, strain KW1T, was isolated from a coastal hydrothermal field on the Satsuma Peninsula, Kagoshima Prefecture, Japan. The variably Gram-stained cells were motile rods with flagella, did not form spores and proliferated at 52-78°C (optimum, 70°C), pH 5-8 (optimum, pH 7...

  6. Dissecting and engineering metabolic and regulatory networks of thermophilic bacteria for biofuel production.

    Science.gov (United States)

    Lin, Lu; Xu, Jian

    2013-11-01

    Interest in thermophilic bacteria as live-cell catalysts in biofuel and biochemical industry has surged in recent years, due to their tolerance of high temperature and wide spectrum of carbon-sources that include cellulose. However their direct employment as microbial cellular factories in the highly demanding industrial conditions has been hindered by uncompetitive biofuel productivity, relatively low tolerance to solvent and osmic stresses, and limitation in genome engineering tools. In this work we review recent advances in dissecting and engineering the metabolic and regulatory networks of thermophilic bacteria for improving the traits of key interest in biofuel industry: cellulose degradation, pentose-hexose co-utilization, and tolerance of thermal, osmotic, and solvent stresses. Moreover, new technologies enabling more efficient genetic engineering of thermophiles were discussed, such as improved electroporation, ultrasound-mediated DNA delivery, as well as thermo-stable plasmids and functional selection systems. Expanded applications of such technological advancements in thermophilic microbes promise to substantiate a synthetic biology perspective, where functional parts, module, chassis, cells and consortia were modularly designed and rationally assembled for the many missions at industry and nature that demand the extraordinary talents of these extremophiles. PMID:23510903

  7. Start-up of a thermophilic upflow anaerobic sludge bed (UASB) reactor with mesophilic granular sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lier, J.B. van; Grolle, K.C.F.; Lettinga, G. (Wageningen Agricultural Univ. (Netherlands). Dept. of Environmental Technology); Stams, A.J.M. (Wageningen Agricultural Univ. (Netherlands). Dept. of Microbiology); Conway de Macario, E. (New York State Dept. of Health, Albany, NY (United States). Wadsworth Center for Laboratories and Research State Univ. of New York, Albany, NY (United States). School of Public Health)

    1992-04-01

    Fast start-up of thermophilic upflow anaerobic sludge bed (UASB) reactors was achieved at process temperatures of 46, 55 and 64deg C, using mesophilic granular sludge as inoculum and fatty acid mixtures as feed. The start-up was brought about by increasing the temperature of mesophilic UASB reactors in a single step, which initially led to a sharp drop in the methane-production rate. Thereafter, stable thermophilic methanogenesis was achieved within a period of 1 or 2 weeks depending on the temperature of operation. Mesophilic granules functioned initially as effective carrier material for thermophilic organisms. However, long-term operation led to disintegration of the granules, resulting in wash-out of thermophilic biomass. The temperature optima for acetotrophic methanogenic activity of the sludges cultivated at 46, 55 and 64deg C, were similar, but differed significantly from the temperature optimum of the mesophilic inoculum. All the sludges examined were dominated by Methanothrix-like rods. These could be distinguished by antigenic fingerprinting into two subpopulations, one predominant at 36deg C and the other predominant at 46deg C and above. (orig.).

  8. Draft Genome Sequence of the Moderately Thermophilic Bacterium Schleiferia thermophila Strain Yellowstone (Bacteroidetes)

    OpenAIRE

    Thiel, Vera; Hamilton, Trinity L.; Tomsho, Lynn P.; Burhans, Richard; Gay, Scott E.; Ramaley, Robert F.; Stephan C Schuster; Steinke, Laurey; Bryant, Donald A.

    2014-01-01

    The draft genome sequence of the moderately thermophilic bacterium Schleiferia thermophila strain Yellowstone (Bacteroidetes), isolated from Octopus Spring (Yellowstone National Park, WY, USA) was sequenced and comprises 2,617,694 bp in 35 contigs. The draft genome is predicted to encode 2,457 protein coding genes and 37 tRNA encoding genes and two rRNA operons.

  9. Strain and bioprocess improvement of a thermophilic anaerobe for the production of ethanol from wood

    OpenAIRE

    Herring, Christopher D; Kenealy, William R.; Joe Shaw, A.; Covalla, Sean F.; Olson, Daniel G; Zhang, Jiayi; Ryan Sillers, W.; Tsakraklides, Vasiliki; Bardsley, John S.; Rogers, Stephen R.; Thorne, Philip G.; Johnson, Jessica P.; Foster, Abigail; Shikhare, Indraneel D.; Klingeman, Dawn M

    2016-01-01

    Background The thermophilic, anaerobic bacterium Thermoanaerobacterium saccharolyticum digests hemicellulose and utilizes the major sugars present in biomass. It was previously engineered to produce ethanol at yields equivalent to yeast. While saccharolytic anaerobes have been long studied as potential biomass-fermenting organisms, development efforts for commercial ethanol production have not been reported. Results Here, we describe the highest ethanol titers achieved from T. saccharolyticum...

  10. Thermophilic anaerobes in arctic marine sediments induced to mineralize complex organic matter at high temperature

    DEFF Research Database (Denmark)

    Hubert, Casey; Arnosti, Carol; Brüchert, Volker;

    2010-01-01

    Marine sediments harbour diverse populations of dormant thermophilic bacterial spores that become active in sediment incubation experiments at much higher than in situ temperature. This response was investigated in the presence of natural complex organic matter in sediments of two Arctic fjords, ...

  11. Treatment of sewage sludge in a thermophilic membrane reactor (TMR) with alternate aeration cycles.

    Science.gov (United States)

    Collivignarelli, Maria Cristina; Castagnola, Federico; Sordi, Marco; Bertanza, Giorgio

    2015-10-01

    The management of sewage sludge is becoming a more and more important issue, both at national and international level, in particular due to the uncertain recovery/disposal future options. Therefore, it is clear that the development of new technologies that can mitigate the problem at the source by reducing sludge production is necessary, such as the European Directive 2008/98/EC prescribes. This work shows the results obtained with a thermophilic membrane reactor, for processing a biological sludge derived from a wastewater treatment plant (WWTP) that treats urban and industrial wastewater. Sewage sludge was treated in a thermophilic membrane reactor (TMR), at pilot-scale (1 m(3) volume), with alternate aeration cycles. The experimentation was divided into two phases: a "startup phase" during which, starting with a psychrophilic/mesophilic biomass, thermophilic conditions were progressively reached, while feeding a highly biodegradable substrate; the obtained thermophilic biomass was then used, in the "regime phase", to digest biological sludge which was fed to the plant. Good removal yields were observed: 64% and 57% for volatile solids (VS) and total COD (CODtot), respectively, with an average hydraulic retention time (HRT) equal to 20 d, an organic loading rate (OLR) of about 1.4-1.8 kg COD m(-3) d(-1) and aeration/non aeration cycles alternated every 4 h.

  12. First Insights into the Genome of the Moderately Thermophilic Bacterium Clostridium tepidiprofundi SG 508T.

    Science.gov (United States)

    Poehlein, Anja; Friedrich, Ines; Krüger, Larissa; Daniel, Rolf

    2016-01-01

    The moderately thermophilic bacterium Clostridium tepidiprofundi is Gram-positive and belongs to clostridial cluster I. It was isolated from a hydrothermal vent chimney. Substrates utilized by C. tepidiprofundi include casein, peptone, tryptone, yeast extract, beef extract, starch, maltose, and glucose. The genome consists of one replicon (3.06 Mb). PMID:27174286

  13. First Insights into the Genome of the Moderately Thermophilic Bacterium Clostridium tepidiprofundi SG 508T

    OpenAIRE

    Poehlein, Anja; Friedrich, Ines; Krüger, Larissa; Daniel, Rolf

    2016-01-01

    The moderately thermophilic bacterium Clostridium tepidiprofundi is Gram-positive and belongs to clostridial cluster I. It was isolated from a hydrothermal vent chimney. Substrates utilized by C. tepidiprofundi include casein, peptone, tryptone, yeast extract, beef extract, starch, maltose, and glucose. The genome consists of one replicon (3.06 Mb).

  14. Growth characteristics of the thermophilic fungus Scytalidium thermophilum in relation to production of mushroom compost.

    NARCIS (Netherlands)

    Wiegant, W.M.

    1992-01-01

    Scytalidium thermophilum is an important thermophilic fungus in the production of mushroom compost. I investigated the characteristics of this organism and present a simple model with which fungal growth in compost can be described. The model is used to predict better circumstances for rapid indoor

  15. Mesophilic and thermophilic alkaline fermentation of waste activated sludge for hydrogen production: Focusing on homoacetogenesis

    DEFF Research Database (Denmark)

    Wan, Jingjing; Jing, Yuhang; Zhang, Shicheng;

    2016-01-01

    The present study compared the mesophilic and thermophilic alkaline fermentation of waste activated sludge (WAS) for hydrogen production with focus on homoacetogenesis, which mediated the consumption of H2 and CO2 for acetate production. Batch experiments showed that hydrogen yield of WAS increased...

  16. Pretreatment of wheat straw and conversion of xylose and xylan to ethanol by thermophilic anaerobic bacteria

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær; Jensen, K.; Nielsen, P.;

    1996-01-01

    . Of five different thermophilic bacteria used in this study only two strains produced ethanol with xylan as substrate, one of them being the strain A3 isolated from an Icelandic hot-spring. Probably other degradation products formed in the presence of oxygen might act as inhibitors. Adaptation...

  17. Electron transfer kinetics of caa(3) oxidase from Bacillus stearothermophilus : A hypothesis for thermophilicity

    NARCIS (Netherlands)

    Giuffre, A; Watmough, NJ; Giannini, S; Brunori, M; Konings, WN; Greenwood, C

    1999-01-01

    The O-2 reaction and the reverse electron transfer of the thermophilic caa, terminal oxidase of Bacillus stearothermophilus have been studied by laser flash-photolysis. The results show that both reactions, although studied at a temperature of 20 degrees C, far from the optimal temperature of > 60 d

  18. Production and partial characterisation of feruloyl esterase by Sporotrichum thermophile in solid-state fermentation

    DEFF Research Database (Denmark)

    Topakas, E.; Kalogeris, E.; Kekos, D.;

    2003-01-01

    A number of factors affecting production of feruloyl esterase an enzyme that hydrolyse ester linkages of ferulic acid (FA) in plant cell walls, by the thermophylic fungus Sporotrichum thermophile under solid state fermentation (SSF) were investigated. Initial moisture content and type of carbon...

  19. Sexual crossing of thermophilic fungus Myceliophthora heterothallica improved enzymatic degradation of sugar beet pulp

    NARCIS (Netherlands)

    Aguilar-Pontes, Maria Victoria; Zhou, Miaomiao; van der Horst, Sjors; Theelen, Bart; de Vries, Ronald P.; van den Brink, Joost

    2016-01-01

    Background Enzymatic degradation of plant biomass requires a complex mixture of many different enzymes. Like most fungi, thermophilic Myceliophthora species therefore have a large set of enzymes targeting different linkages in plant polysaccharides. The majority of these enzymes have not been functi

  20. Thermophilic Campylobacter spp. in turkey samples: evaluation of two automated enzyme immunoassays and conventional microbiological techniques

    DEFF Research Database (Denmark)

    Borck, Birgitte; Stryhn, H.; Ersboll, A.K.;

    2002-01-01

    Aims: To determine the sensitivity and specificity of two automated enzyme immunoassays (EIA), EiaFoss and Minividas, and a conventional microbiological culture technique for detecting thermophilic Campylobacter spp. in turkey samples. Methods and Results: A total of 286 samples (faecal, meat...

  1. Thermophilic fermentative hydrogen production by the newly isolated Thermoanaerobacterium thermosaccharolyticum PSU-2

    DEFF Research Database (Denmark)

    O-Thong, Sompong; Prasertsan, P.; Karakashev, Dimitar Borisov;

    2008-01-01

    A thermophilic H(2)-producing bacterial strain was isolated from a biohydrogen reactor fed with palm oil mill effluent (POME) and identified as Thermoanaerobacterium thermosaccharolyticum using 16S rRNA gene analysis. The isolated bacterium, designated as T thermosaccharolyticum PSU-2, showed...

  2. Glycolytic pathway and hydrogen yield studies of the extreme thermophile Caldicellulosiruptor saccharolyticus

    NARCIS (Netherlands)

    Vrije, de G.J.; Mars, A.E.; Budde, M.A.W.; Lai, M.H.; Dijkema, C.; Waard, de P.; Claassen, P.A.M.

    2007-01-01

    NMR analysis of 13C-labelling patterns showed that the Embden¿Meyerhof (EM) pathway is the main route for glycolysis in the extreme thermophile Caldicellulosiruptor saccharolyticus. Glucose fermentation via the EM pathway to acetate results in a theoretical yield of 4 mol of hydrogen and 2 mol of ac

  3. Optimisation of sulphate reduction in a methanol-fed thermophilic bioreactor

    NARCIS (Netherlands)

    Weijma, J.; Bots, E.A.A.; Tandlinger, G.; Stams, A.J.M.; Hulshoff Pol, L.W.; Lettinga, G.

    2002-01-01

    Several methods were tested to optimise sulphate reduction and minimise methane formation in thermophilic (65°) expanded granular sludge bed reactors fed with a medium containing sulphate and methanol. Lowering the pH from 7.5 to 6.75 resulted in a rapid decrease of methane formation and a concomita

  4. Biogas Upgrading via Hydrogenotrophic Methanogenesis in Two-Stage Continuous Stirred Tank Reactors at Mesophilic and Thermophilic Conditions

    DEFF Research Database (Denmark)

    Bassani, Ilaria; Kougias, Panagiotis; Treu, Laura;

    2015-01-01

    This study proposes an innovative setup composed by two stage reactors to achieve biogas upgrading coupling the CO2 in the biogas with external H2 and subsequent conversion into CH4 by hydrogenotrophic methanogenesis. In this configuration, the biogas produced in the first reactor was transferred...... to the second one, where H2 was injected. This configuration was tested at both mesophilic and thermophilic conditions. After H2 addition, the produced biogas was upgraded to average CH4 content of 89% in the mesophilic reactor and 85% in the thermophilic. At thermophilic conditions, a higher efficiency of CH4...

  5. Influence of an aerobic fungus grown on solid culture on ruminal degradability and on a mixture culture of anaerobic cellulolytic bacteria.

    Science.gov (United States)

    Hernández-Díaz, R; Pimentel-González, D J; Figueira, A C; Viniegra-González, G; Campos-Montiel, R G

    2010-06-01

    In this work, the effect of a solid fungal culture of Aspergillus niger (An) grown on coffee pulp on the in situ ruminal degradability (RD) of corn stover was evaluated. In addition, the effect of its extracts on the in vitro dry matter disappearance (IVDMD) and on a mixed culture of anaerobic cellulolytic bacteria (MCACB) was also investigated. The solid ferment was a crude culture of An, grown on coffee pulp. Regarding in situ RD, a significant difference (p < 0.05) was found between treatment with 200 g/day of the solid culture and control (no solid culture added) on dry matter, crude protein and neutral detergent fibre on RD. All the water extracts (pH 4, 7 and 10) enhanced IVDMD and stimulated the cellulolytic activity on a MCACB. Ultrafiltration results showed that active compounds with a molecular weight lower than 30 kDa were responsible for the effect on MCACB. Such results suggest that the effects of the solid An culture in RD are related to the presence of water soluble compounds having a molecular weight lower than 30 kDa.

  6. Production and assay of cellulolytic enzyme activity of Enterobacter cloacae WPL 214 isolated from bovine rumen fluid waste of Surabaya abbatoir, Indonesia

    Directory of Open Access Journals (Sweden)

    W. P. Lokapirnasari

    2015-03-01

    Full Text Available Aim: This study aims to produce and assay cellulolytic enzyme activity (endo-(1,4-β-D-glucanase, exo-(1,4-β-Dglucanase, and β-glucosidase, at optimum temperature and optimum pH of Enterobacter cloacae WPL 214 isolated from bovine rumen fluid waste of Surabaya Abbatoir, Indonesia. Materials and Methods: To produce enzyme from a single colony of E. cloacae WPL 214, 98 × 1010 CFU/ml of isolates was put into 20 ml of liquid medium and incubated in a shaker incubator for 16 h at 35°C in accordance with growth time and optimum temperature of E. cloacae WPL 214. Further on, culture was centrifuged at 6000 rpm at 4°C for 15 min. Pellet was discarded while supernatant containing cellulose enzyme activity was withdrawn to assay endo-(1,4-β-D-glucanase, exo-(1,4-β-D-glucanase, and β-glucosidase. Results: Cellulase enzyme of E. cloacae WPL 214 isolates had endoglucanase activity of 0.09 U/ml, exoglucanase of 0.13 U/ml, and cellobiase of 0.10 U/ml at optimum temperature 35°C and optimum pH 5. Conclusion: E. cloacae WPL 214 isolated from bovine rumen fluid waste produced cellulose enzyme with activity as cellulolytic enzyme of endo-(1,4-β-D-glucanase, exo-(1,4-β-D-glucanase and β-glucosidase.

  7. A semi-continuous culture system for production of cellulolytic and xylanolytic enzymes by the anaerobic fungus Piromyces sp. strain E2

    Energy Technology Data Exchange (ETDEWEB)

    Teunissen, M.J.; Baerends, R.J.S.; Knelissen, R.A.G.; Camp, H.J.M. op den; Vogels, G.D. (Katholieke Univ., Nijmegen (Netherlands). Dept. of Microbiology)

    1992-10-01

    A system was developed for the semi-continous cultivation of an anaerobic fungus, Piromyces sp. strain E2 (isolated from an Indian elephant), on Avicel (microcrystalline cellulose). The fungus was grown in a semi-continuous culture system: Solids and fungal biomass was retained by means of a simple filter construction whereas the culture fluid was removed continuously. The production of fermentation products (acetate, ethanol, formate, lactate, hydrogen or methane), cellulolytic and xylanolytic enzymes, and protein by the fungus in monoculture or co-culture with Methanobacterium formicicum during growth on Avicel was monitored up to 45 days. These productions stabilized after an adaptation period of 24 and 30 days in the semi-continuous co-culture and monoculture, respectively. After this period the average ([+-]SD) avicelase, [beta]-glucosidase, endoglucanase, and xylanase production in the semicontinuous monoculture were 27[+-]6, 140[+-]16, 1057[+-]120 and 5012[+-]583 IUxl[sup -1]xday[sup -1], respectively. Co-culture with the methanogen caused a shift in fermentation products to more acetate, and less ethanol and lactate. Furthermore, the production of all cellulolytic enzymes increased (40%) and xylanolytic enzyme production decreased (35%). (orig.).

  8. Effect of feeding palm oil by-products based diets on total bacteria, cellulolytic bacteria and methanogenic archaea in the rumen of goats.

    Directory of Open Access Journals (Sweden)

    Abdelrahim Abubakr

    Full Text Available Rumen microorganisms are responsible for digestion and utilization of dietary feeds by host ruminants. Unconventional feed resources could be used as alternatives in tropical areas where feed resources are insufficient in terms of quality and quantity. The objective of the present experiment was to evaluate the effect of diets based on palm oil (PO, decanter cake (DC or palm kernel cake (PKC on rumen total bacteria, selected cellulolytic bacteria, and methanogenic archaea. Four diets: control diet (CD, decanter cake diet (DCD, palm kernel cake diet (PKCD and CD plus 5% PO diet (CPOD were fed to rumen cannulated goats and rumen samples were collected at the start of the experimental diets (day 0 and on days 4, 6, 8, 12, 18, 24 and 30 post dietary treatments. Feeding DCD and PKCD resulted in significantly higher (P<0.05 DNA copy number of total bacteria, Fibrobacter succinogenes, Ruminococcus flavefeciens, and Ruminococcus albus. Rumen methanogenic archaea was significantly lower (P<0.05 in goats fed PKCD and CPOD and the trend showed a severe reduction on days 4 and 6 post experimental diets. In conclusion, results indicated that feeding DCD and PKC increased the populations of cellulolytic bacteria and decreased the density of methanogenic archaea in the rumen of goats.

  9. Deep Conversion of Carbon Monoxide to Hydrogen and Formation of Acetate by the Anaerobic Thermophile Carboxydothermus hydrogenoformans

    NARCIS (Netherlands)

    Henstra, A.M.; Stams, A.J.M.

    2011-01-01

    Carboxydothermus hydrogenoformans is a thermophilic strictly anaerobic bacterium that catalyses the water gas shift reaction, the conversion of carbon monoxide with water to molecular hydrogen and carbon dioxide. The thermodynamically favorable growth temperature, compared to existing industrial cat

  10. Tryptophan Oxidative Metabolism Catalyzed by Geobacillus Stearothermophilus: A Thermophile Isolated from Kuwait Soil Contaminated with Petroleum Hydrocarbons

    OpenAIRE

    Al-Hassan, Jassim M.; Samira Al-Awadi; Sosamma Oommen; Abdulaziz Alkhamis; Mohammad Afzal

    2011-01-01

    Tryptophan metabolism has been extensively studied in humans as well as in soil. Its metabolism takes place mainly through kynurenine pathway yielding hydroxylated, deaminated and many other products of physiological significance. However, tryptophan metabolism has not been studied in an isolated thermophilic bacterium. Geobacillus stearothermophilus is a local thermophile isolated from Kuwait desert soil contaminated with petroleum hydrocarbons. The bacterium grows well at 65 °C in 0.05 M ph...

  11. Ecology of Thermophilic Fungi in Mushroom Compost, with Emphasis on Scytalidium thermophilum and Growth Stimulation of Agaricus bisporus Mycelium

    OpenAIRE

    Straatsma, Gerben; Samson, Robert A.; Olijnsma, Tineke W.; Op den Camp, Huub J. M.; Gerrits, Jan P. G.; Van Griensven, Leo J. L. D.

    1994-01-01

    Twenty-two species of thermophilic fungi were isolated from mushroom compost. Scytalidium thermophilum was present in the compost ingredients, fresh straw, horse droppings, and drainage from compost and dominated the fungal biota of compost after preparation. Of 34 species of thermophilic fungi tested, 9 promoted mycelial growth of Agaricus bisporus on sterilized compost: Chaetomium thermophilum, an unidentified Chaetomium sp., Malbranchea sulfurea, Myriococcum thermophilum, S. thermophilum, ...

  12. Thermophilic anaerobic digestion of sewage sludge: focus on the influence of the start-up. A review.

    Science.gov (United States)

    De la Rubia, M A; Riau, V; Raposo, F; Borja, R

    2013-12-01

    The thermophilic anaerobic digestion (TAD) of sewage sludge has often been found to be less stable than mesophilic treatment. In comparison to mesophilic digesters, thermophilic reactors treating sludge are generally characterized by relatively high concentrations of volatile fatty acids (VFA) in the effluent along with poor effluent quality, indicating a lower level of process stability. However, reviewing the literature related to the procedure for obtaining a thermophilic inoculum, it seems that most of the problems associated with the instability and the accumulation of organic intermediates are the result of the manner in which the thermophilic sludge has been obtained. In this paper, the different options available for obtaining an anaerobic digester operating at thermophilic temperature (55°C) have been reviewed. In this light, rapid heating to the target temperature followed by the development of thermophilic microorganisms, which can be determined by VFA dropping to ≤ 500 mg acetic acid L(-1) before increasing the organic loading rate (OLR), has been determined the most suitable means of establishing TAD.

  13. Decontamination of heavy metal laden sewage sludge with simultaneous solids reduction using thermophilic sulfur and ferrous oxidizing species.

    Science.gov (United States)

    Mehrotra, A; Kundu, K; Sreekrishnan, T R

    2016-02-01

    A possibility of using simultaneous sewage sludge digestion and metal leaching (SSDML) process at the thermophilic temperature to remove heavy metals and suspended solids from sewage sludge is explored in this study. Though thermophilic sludge digestion efficiently produces a stable sludge, its inability to remove heavy metals requires it to be used in tandem with another process like bioleaching for metal reduction. Previously, different temperature optima were known for the heterotrophs (thermophilic) responsible for the sludge digestion and the autotrophs involved in bioleaching (mesophilic), because of which the metal concentration was brought down separately in a different reactor. In our study, SSDML process was carried out at 50 °C (thermophilic) by using ferrous sulfate (batch-1) and sulfur (batch-2) as the energy source in two reactors. The concentration of volatile suspended solids reduced by >40% in both batches, while that of heavy metals zinc, copper, chromium, cadmium and nickel decreased by >50% in both batch-1 and batch-2. Lead got leached out only in batch-1. Using 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis analysis, Alicyclobacillus tolerans was found to be the microorganism responsible for lowering the pH in both the reactors at thermophilic temperature. The indicator organism count was also below the maximum permissible limit making sludge suitable for agricultural use. Our results indicate that SSDML at thermophilic temperature can be effectively used for reduction of heavy metals and suspended solids from sewage sludge. PMID:26686075

  14. Decontamination of heavy metal laden sewage sludge with simultaneous solids reduction using thermophilic sulfur and ferrous oxidizing species.

    Science.gov (United States)

    Mehrotra, A; Kundu, K; Sreekrishnan, T R

    2016-02-01

    A possibility of using simultaneous sewage sludge digestion and metal leaching (SSDML) process at the thermophilic temperature to remove heavy metals and suspended solids from sewage sludge is explored in this study. Though thermophilic sludge digestion efficiently produces a stable sludge, its inability to remove heavy metals requires it to be used in tandem with another process like bioleaching for metal reduction. Previously, different temperature optima were known for the heterotrophs (thermophilic) responsible for the sludge digestion and the autotrophs involved in bioleaching (mesophilic), because of which the metal concentration was brought down separately in a different reactor. In our study, SSDML process was carried out at 50 °C (thermophilic) by using ferrous sulfate (batch-1) and sulfur (batch-2) as the energy source in two reactors. The concentration of volatile suspended solids reduced by >40% in both batches, while that of heavy metals zinc, copper, chromium, cadmium and nickel decreased by >50% in both batch-1 and batch-2. Lead got leached out only in batch-1. Using 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis analysis, Alicyclobacillus tolerans was found to be the microorganism responsible for lowering the pH in both the reactors at thermophilic temperature. The indicator organism count was also below the maximum permissible limit making sludge suitable for agricultural use. Our results indicate that SSDML at thermophilic temperature can be effectively used for reduction of heavy metals and suspended solids from sewage sludge.

  15. Draft genome sequence of Herbinix hemicellulosilytica T3/55 T, a new thermophilic cellulose degrading bacterium isolated from a thermophilic biogas reactor.

    Science.gov (United States)

    Koeck, Daniela E; Maus, Irena; Wibberg, Daniel; Winkler, Anika; Zverlov, Vladimir V; Liebl, Wolfgang; Pühler, Alfred; Schwarz, Wolfgang H; Schlüter, Andreas

    2015-11-20

    A novel bacterial species was isolated from an industrial-scale biogas plant. The isolate Herbinix hemicellulosilytica T3/55(T) is able to degrade crystalline cellulose. Comparative 16S rRNA gene sequencing demonstrated that the isolate is closely related to environmental samples forming a hitherto unknown sub-cluster within the family Lachnospiraceae. The draft genome sequence of strain T3/55(T) was established and now provides the genetic basis for application of this microorganism in thermophilic degradation of lignocellulosic biomass.

  16. Thermophile-specific proteins: the gene product of aq_1292 from Aquifex aeolicus is an NTPase

    OpenAIRE

    Howe Rebecca; Roßbach Michael; Klinger Claudia; Kaufmann Michael

    2003-01-01

    Abstract Background To identify thermophile-specific proteins, we performed phylogenetic patterns searches of 66 completely sequenced microbial genomes. This analysis revealed a cluster of orthologous groups (COG1618) which contains a protein from every thermophile and no sequence from 52 out of 53 mesophilic genomes. Thus, COG1618 proteins belong to the group of thermophile-specific proteins (THEPs) and therefore we here designate COG1618 proteins as THEP1s. Since no THEP1 had been analyzed ...

  17. The genome sequences of Cellulomonas fimi and "Cellvibrio gilvus" reveal the cellulolytic strategies of two facultative anaerobes, transfer of "Cellvibrio gilvus" to the genus Cellulomonas, and proposal of Cellulomonas gilvus sp. nov.

    Directory of Open Access Journals (Sweden)

    Melissa R Christopherson

    Full Text Available Actinobacteria in the genus Cellulomonas are the only known and reported cellulolytic facultative anaerobes. To better understand the cellulolytic strategy employed by these bacteria, we sequenced the genome of the Cellulomonas fimi ATCC 484(T. For comparative purposes, we also sequenced the genome of the aerobic cellulolytic "Cellvibrio gilvus" ATCC 13127(T. An initial analysis of these genomes using phylogenetic and whole-genome comparison revealed that "Cellvibrio gilvus" belongs to the genus Cellulomonas. We thus propose to assign "Cellvibrio gilvus" to the genus Cellulomonas. A comparative genomics analysis between these two Cellulomonas genome sequences and the recently completed genome for Cellulomonas flavigena ATCC 482(T showed that these cellulomonads do not encode cellulosomes but appear to degrade cellulose by secreting multi-domain glycoside hydrolases. Despite the minimal number of carbohydrate-active enzymes encoded by these genomes, as compared to other known cellulolytic organisms, these bacteria were found to be proficient at degrading and utilizing a diverse set of carbohydrates, including crystalline cellulose. Moreover, they also encode for proteins required for the fermentation of hexose and xylose sugars into products such as ethanol. Finally, we found relatively few significant differences between the predicted carbohydrate-active enzymes encoded by these Cellulomonas genomes, in contrast to previous studies reporting differences in physiological approaches for carbohydrate degradation. Our sequencing and analysis of these genomes sheds light onto the mechanism through which these facultative anaerobes degrade cellulose, suggesting that the sequenced cellulomonads use secreted, multidomain enzymes to degrade cellulose in a way that is distinct from known anaerobic cellulolytic strategies.

  18. Identification and characterization of diverse xylanases from thermophilic and thermotolerant fungi

    Directory of Open Access Journals (Sweden)

    Bhat, M. K.

    2006-07-01

    Full Text Available Thirteen fungal isolates included in this study expressed multiple xylanase isoforms as observed by xylan zymograms of polyacrylamide gel electrophoresis (PAGE and isoelectrofocussing (IEF fractionated proteins. Eighty-three xylanases produced by these thermophilic and thermotolerant strains were detected using the IEF profiling technique. Xylanases identified on the basis of their isoelectric points (pI were functionally diverse and exhibited differential catalytic activities against various xylan types (birch wood xylan, larch wood xylan, oat spelt xylan, rye arabino xylan and wheat arabino xylan as well as debranched arabinan. Thermophilic isolates, Chaetomium thermophilum, Humicola insolens, Melanocarpus sp., Malbranchea sp. and Thermoascus aurantiacus, were found to produce alkaline active xylanases that showed a bleach boosting effect on Decker pulp resulting in increased brightness (1.60-2.04 ISO units.

  19. Effects of total solids content on waste activated sludge thermophilic anaerobic digestion and its sludge dewaterability.

    Science.gov (United States)

    Wang, Tianfeng; Chen, Jie; Shen, Honglang; An, Dong

    2016-10-01

    The role of total solids content on sludge thermophilic anaerobic digestion was investigated in batch reactors. A range of total solids content from 2% to 10% was evaluated with two replicates. The lowest inhibitory concentration for free ammonia and total ammonia of sludge thermophilic anaerobic digestion was 110.9-171.4mg/L and 1313.1-1806.7mg/L, respectively. The volumetric biogas production rate increased with increasing of total solids content, but the corresponding biogas yield per gram volatile solid decreased. The result of normalized capillary suction time indicated that the dewaterability of digested sludge at high total solids content was poor, while solid content of sediment obtained by centrifuging sludge at 2000g for 10min increased with increasing of total solids content of sludge. The results suggest that thickened sludge mixed with dewatered sludge at an appropriate ratio could get high organic loading rate, high biogas yield and adequate dewatering effort. PMID:26897469

  20. An integrated approach for genome annotation of the eukaryotic thermophile Chaetomium thermophilum.

    Science.gov (United States)

    Bock, Thomas; Chen, Wei-Hua; Ori, Alessandro; Malik, Nayab; Silva-Martin, Noella; Huerta-Cepas, Jaime; Powell, Sean T; Kastritis, Panagiotis L; Smyshlyaev, Georgy; Vonkova, Ivana; Kirkpatrick, Joanna; Doerks, Tobias; Nesme, Leo; Baßler, Jochen; Kos, Martin; Hurt, Ed; Carlomagno, Teresa; Gavin, Anne-Claude; Barabas, Orsolya; Müller, Christoph W; van Noort, Vera; Beck, Martin; Bork, Peer

    2014-12-16

    The thermophilic fungus Chaetomium thermophilum holds great promise for structural biology. To increase the efficiency of its biochemical and structural characterization and to explore its thermophilic properties beyond those of individual proteins, we obtained transcriptomics and proteomics data, and integrated them with computational annotation methods and a multitude of biochemical experiments conducted by the structural biology community. We considerably improved the genome annotation of Chaetomium thermophilum and characterized the transcripts and expression of thousands of genes. We furthermore show that the composition and structure of the expressed proteome of Chaetomium thermophilum is similar to its mesophilic relatives. Data were deposited in a publicly available repository and provide a rich source to the structural biology community. PMID:25398899

  1. Ammonia inhibition on hydrogen enriched anaerobic digestion of manure under mesophilic and thermophilic conditions

    DEFF Research Database (Denmark)

    Wang, Han; Zhang, Yifeng; Angelidaki, Irini

    2016-01-01

    Capturing of carbon dioxide by hydrogen derived from excess renewable energy (e.g., wind mills) to methane in a microbially catalyzed process offers an attractive technology for biogas production and upgrading. This bioconversion process is catalyzed by hydrogenotrophic methanogens, which are known...... to be sensitive to ammonia. In this study, the tolerance of the biogas process under supply of hydrogen, to ammonia toxicity was studied under mesophilic and thermophilic conditions. When the initial hydrogen partial pressure was 0.5 atm, the methane yield at high ammonia load (7 g NH4+-N L−1) was 41.0% and 22...... methanogens in the hydrogen enriched biogas production and upgrading processes. The highest methane production yield was achieved under 0.5 atm hydrogen partial pressure in batch reactors at all the tested ammonia levels. Furthermore, the thermophilic methanogens at 0.5 atm of hydrogen partial pressure were...

  2. A Highly Stable d-Amino Acid Oxidase of the Thermophilic Bacterium Rubrobacter xylanophilus

    OpenAIRE

    Takahashi, Shouji; Furukawara, Makoto; Omae, Keishi; Tadokoro, Namiho; Saito, Yayoi; Abe, Katsumasa; Kera, Yoshio

    2014-01-01

    d-Amino acid oxidase (DAO) is a biotechnologically attractive enzyme that can be used in a variety of applications, but its utility is limited by its relatively poor stability. A search of a bacterial genome database revealed a gene encoding a protein homologous to DAO in the thermophilic bacterium Rubrobacter xylanophilus (RxDAO). The recombinant protein expressed in Escherichia coli was a monomeric protein containing noncovalently bound flavin adenine dinucleotide as a cofactor. This protei...

  3. Regularities of polymer substances transformation into methane by thermophilic anaerobic bacteria

    OpenAIRE

    V. І. Karpenko; L. S. Yastremska; І. G. Burun; Y. V. Lembey; O. S. Tatarchenko

    2006-01-01

    The paper shows the regularities of polymer substances transformation into methane by extracted thermophilic anaerobic bacteria. The sequence of substrate use by the methane generating bacteria corresponds to the energy efficiency of the methane genesis reactions as in the first place hydrogen is used and then acetate is. Combined cultivation of extracted different anaerobic cultures gives the opportunity to increase ethanol and hydrogen yield as well as the effectiveness of methane formation.

  4. Evaluation of dairy powder products implicates thermophilic sporeformers as the primary organisms of interest.

    Science.gov (United States)

    Watterson, M J; Kent, D J; Boor, K J; Wiedmann, M; Martin, N H

    2014-01-01

    Dairy powder products (e.g., sweet whey, nonfat dry milk, acid whey, and whey protein concentrate-80) are of economic interest to the dairy industry. According to the US Dairy Export Council, customers have set strict tolerances (dairy powders; therefore, understanding proliferation and survival of sporeforming organisms within dairy powder processing plants is necessary to control and reduce sporeformer counts. Raw, work-in-process, and finished product samples were collected from 4 dairy powder processing facilities in the northeastern United States over a 1-yr period. Two separate spore treatments: (1) 80°C for 12min (to detect sporeformers) and (2) 100°C for 30min (to detect highly heat resistant sporeformers) were applied to samples before microbiological analyses. Raw material, work-in-process, and finished product samples were analyzed for thermophilic, mesophilic, and psychrotolerant sporeformers, with 77.5, 71.0, and 4.6% of samples being positive for those organisms, respectively. Work-in-process and finished product samples were also analyzed for highly heat resistant thermophilic and mesophilic sporeformers, with 63.7 and 42.6% of samples being positive, respectively. Sporeformer prevalence and counts varied considerably by product and plant; sweet whey and nonfat dry milk showed a higher prevalence of thermophilic and mesophilic sporeformers compared with acid whey and whey protein concentrate-80. Unlike previous reports, we found limited evidence for increased spore counts toward the end of processing runs. Our data provide important insight into spore contamination patterns associated with production of different types of dairy powders and support that thermophilic sporeformers are the primary organism of concern in dairy powders.

  5. Thermophile-specific proteins: the gene product of aq_1292 from Aquifex aeolicus is an NTPase

    Directory of Open Access Journals (Sweden)

    Howe Rebecca

    2003-09-01

    Full Text Available Abstract Background To identify thermophile-specific proteins, we performed phylogenetic patterns searches of 66 completely sequenced microbial genomes. This analysis revealed a cluster of orthologous groups (COG1618 which contains a protein from every thermophile and no sequence from 52 out of 53 mesophilic genomes. Thus, COG1618 proteins belong to the group of thermophile-specific proteins (THEPs and therefore we here designate COG1618 proteins as THEP1s. Since no THEP1 had been analyzed biochemically thus far, we characterized the gene product of aq_1292 which is THEP1 from the hyperthermophilic bacterium Aquifex aeolicus (aaTHEP1. Results aaTHEP1 was cloned in E. coli, expressed and purified to homogeneity. At a temperature optimum between 70 and 80°C, aaTHEP1 shows enzymatic activity in hydrolyzing ATP to ADP + Pi with kcat = 5 × 10-3 s-1 and Km = 5.5 × 10-6 M. In addition, the enzyme exhibits GTPase activity (kcat = 9 × 10-3 s-1 and Km= 45 × 10-6 M. aaTHEP1 is inhibited competitively by CTP, UTP, dATP, dGTP, dCTP, and dTTP. As shown by gel filtration, aaTHEP1 in its purified state appears as a monomer. The enzyme is resistant to limited proteolysis suggesting that it consists of a single domain. Although THEP1s are annotated as "predicted nucleotide kinases" we could not confirm such an activity experimentally. Conclusion Since aaTHEP1 is the first member of COG1618 that is characterized biochemically and functional information about one member of a COG may be transferred to the entire COG, we conclude that COG1618 proteins are a family of thermophilic NTPases.

  6. Engineering pyruvate decarboxylase-mediated ethanol production in the thermophilic host Geobacillus thermoglucosidasius.

    Science.gov (United States)

    Van Zyl, L J; Taylor, M P; Eley, K; Tuffin, M; Cowan, D A

    2014-02-01

    This study reports the expression, purification, and kinetic characterization of a pyruvate decarboxylase (PDC) from Gluconobacter oxydans. Kinetic analyses showed the enzyme to have high affinity for pyruvate (120 μM at pH 5), high catalytic efficiency (4.75 × 10(5) M(-1) s(-1) at pH 5), a pHopt of approximately 4.5 and an in vitro temperature optimum at approximately 55 °C. Due to in vitro thermostablity (approximately 40 % enzyme activity retained after 30 min at 65 °C), this PDC was considered to be a suitable candidate for heterologous expression in the thermophile Geobacillus thermoglucosidasius for ethanol production. Initial studies using a variety of methods failed to detect activity at any growth temperature (45-55 °C). However, the application of codon harmonization (i.e., mimicry of the heterogeneous host's transcription and translational rhythm) yielded a protein that was fully functional in the thermophilic strain at 45 °C (as determined by enzyme activity, Western blot, mRNA detection, and ethanol productivity). Here, we describe the first successful expression of PDC in a true thermophile. Yields as high as 0.35 ± 0.04 g/g ethanol per gram of glucose consumed were detected, highly competitive to those reported in ethanologenic thermophilic mutants. Although activities could not be detected at temperatures approaching the growth optimum for the strain, this study highlights the possibility that previously unsuccessful expression of pdcs in Geobacillus spp. may be the result of ineffective transcription/translation coupling.

  7. Survey of thermophilic Campylobacter species in cats and dogs in north-western Nigeria

    OpenAIRE

    Adewale Kolawale; Junaidu U. Abdulkadir; Abdullahi A. Magaji; Mohammed D. Salihu

    2010-01-01

    This study was conducted in north-western Nigeria to investigate the role of cats and dogs as potential reservoirs of thermophilic Campylobacter species. Faecal samples were analysed from 104 cats and 141 dogs between March 2007 and March 2009. The samples were collected from animals in households, those presented to veterinary premises and feline colonies. Campylobacter spp. were isolated from 39 (27.7%) and 19 (18.3%) dogs and cats, respectively. There was no significant difference in isola...

  8. A constant flux of diverse thermophilic bacteria into the cold arctic seabed

    DEFF Research Database (Denmark)

    Hubert, Casey; Loy, Alexander; Nickel, Maren;

    2009-01-01

    Microorganisms have been repeatedly discovered in environments that do not support their metabolic activity. Identifying and quantifying these misplaced organisms can reveal dispersal mechanisms that shape natural microbial diversity. Using endospore germination experiments, we estimated a stable...... supply of thermophilic bacteria into permanently cold Arctic marine sediment at a rate exceeding 108 spores per square meter per year. These metabolically and phylogenetically diverse Firmicutes show no detectable activity at cold in situ temperatures but rapidly mineralize organic matter by hydrolysis...

  9. A study of the oxygen and carbon dioxide requirements of thermophilic campylobacters.

    OpenAIRE

    Bolton, F J; Coates, D.

    1983-01-01

    The oxygen and carbon dioxide requirements of different biotypes of thermophilic campylobacters were investigated by means of (a) quantitative studies, and (b) total growth studies. Oxygen tolerance of the five test organisms differed markedly and varied with the carbon dioxide concentration. At most carbon dioxide concentrations tested, Campylobacter jejuni strains NCTC 11168 and NCTC 11392 tolerated 21% oxygen (growth reduced), C coli NCTC 11353 tolerated 15% oxygen (growth reduced), and C ...

  10. Growth-promoting effect of thermophilic fungi on the mycelium of the edible mushroom Agaricus bisporus.

    OpenAIRE

    Wiegant, W.M.; Wery, J.; E. T. Buitenhuis; de Bont, J A

    1992-01-01

    The growth-promoting effect of the thermophilic fungus Scytalidium thermophilum in mushroom compost on the mycelium of the edible mushroom Agaricus bisporus was investigated. Results obtained by others were confirmed by showing that S. thermophilum leads to an increased hyphal extension rate of the mushroom mycelium. However, it was demonstrated that hyphal extension rates were not clearly related to mushroom biomass increase rates. A number of experiments pointed strongly towards CO2 as the ...

  11. Comparing mesophilic and thermophilic anaerobic digestion of chicken manure: Microbial community dynamics and process resilience

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Qigui; Takemura, Yasuyuki; Kubota, Kengo [Department of Civil and Environmental Engineering, Graduate School of Engineering Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Li, Yu-You, E-mail: yyli@epl1.civil.tohoku.ac.jp [Department of Civil and Environmental Engineering, Graduate School of Engineering Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an (China)

    2015-09-15

    Highlights: • Microbial community dynamics and process functional resilience were investigated. • The threshold of TAN in mesophilic reactor was higher than the thermophilic reactor. • The recoverable archaeal community dynamic sustained the process resilience. • Methanosarcina was more sensitive than Methanoculleus on ammonia inhibition. • TAN and FA effects the dynamic of hydrolytic and acidogenic bacteria obviously. - Abstract: While methane fermentation is considered as the most successful bioenergy treatment for chicken manure, the relationship between operational performance and the dynamic transition of archaeal and bacterial communities remains poorly understood. Two continuous stirred-tank reactors were investigated under thermophilic and mesophilic conditions feeding with 10%TS. The tolerance of thermophilic reactor on total ammonia nitrogen (TAN) was found to be 8000 mg/L with free ammonia (FA) 2000 mg/L compared to 16,000 mg/L (FA1500 mg/L) of mesophilic reactor. Biomethane production was 0.29 L/gV S{sub in} in the steady stage and decreased following TAN increase. After serious inhibition, the mesophilic reactor was recovered successfully by dilution and washing stratagem compared to the unrecoverable of thermophilic reactor. The relationship between the microbial community structure, the bioreactor performance and inhibitors such as TAN, FA, and volatile fatty acid was evaluated by canonical correspondence analysis. The performance of methanogenic activity and substrate removal efficiency were changed significantly correlating with the community evenness and phylogenetic structure. The resilient archaeal community was found even after serious inhibition in both reactors. Obvious dynamics of bacterial communities were observed in acidogenic and hydrolytic functional bacteria following TAN variation in the different stages.

  12. Production, purification and characterization of xylanase using alkalo-thermophilic Bacillus halodurans KR-1

    OpenAIRE

    Krityanand Kumar Mahatman; Neha Garg; Ranjeeta Chauhan; Anil Kumar

    2010-01-01

    Xylanase (EC. 3.2.1.8) has been isolated from an alkalo-thermophilic bacteria, Bacillus halodurans strain KR-1 isolated from the soil near river bed at Indore. The bacteria secreted xylanase in the growth medium in the presence of xylan. The production of the enzyme was induced in the presence of glucose, mannose, lactose and maltose whereas presence of starch, cellulose and sucrose retarded in enzyme production. The presence of casein, peptone, sodium nitrate and potassium nitrate as nitroge...

  13. Autohydrolysis of plant xylans by apoplastic expression of thermophilic bacterial endo-xylanases

    DEFF Research Database (Denmark)

    Borkhardt, Bernhard; Harholt, Jesper; Ulvskov, Peter Bjarne;

    2010-01-01

    The genes encoding the two endo-xylanases XynA and XynB from the thermophilic bacterium Dictyoglomus thermophilum were codon optimized for expression in plants. Both xylanases were designed to be constitutively expressed under the control of the CaMV 35S promoter and targeted to the apoplast. Tra...... treatment of wildtype and transgenic extracts from dry stems showed a decrease in the molecular weight of xylans from transgenic stems....

  14. Bioleaching of electronic scrap by mixed culture of moderately thermophilic microorganisms

    OpenAIRE

    Ivănuş D.; Ivănuş R.C.; Călmuc F.

    2010-01-01

    A process for the metal recovery from electronic scrap using bacterial leaching was investigated. A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages (AMDs) samples collected from several sulphide mines in Romania, and the bioleaching of electronic scrap was conducted both in shake flask and bioreactor. The results show that in the shake flask, the mixture can tolerate 50 g/L scrap after being acclimated to gradually increased concentrations o...

  15. Optimization of key factors affecting hydrogen production from sugarcane bagasse by a thermophilic anaerobic pure culture

    OpenAIRE

    Lai, Zhicheng; Zhu, Muzi; Yang, Xiaofeng; Wang, JuFang; Li, Shuang

    2014-01-01

    Background Hydrogen is regarded as an attractive future energy carrier for its high energy content and zero CO2 emission. Currently, the majority of hydrogen is generated from fossil fuels. However, from an environmental perspective, sustainable hydrogen production from low-cost lignocellulosic biomass should be considered. Thermophilic hydrogen production is attractive, since it can potentially convert a variety of biomass-based substrates into hydrogen at high yields. Results Sugarcane baga...

  16. Physiological characteristics of the extreme thermophile Caldicellulosiruptor saccharolyticus: an efficient hydrogen cell factory

    OpenAIRE

    Zeidan Ahmad A; Willquist Karin; van Niel Ed WJ

    2010-01-01

    Abstract Global concerns about climate changes and their association with the use of fossil fuels have accelerated research on biological fuel production. Biological hydrogen production from hemicellulose-containing waste is considered one of the promising avenues. A major economical issue for such a process, however, is the low substrate conversion efficiency. Interestingly, the extreme thermophilic bacterium Caldicellulosiruptor saccharolyticus can produce hydrogen from carbohydrate-rich su...

  17. Comparing mesophilic and thermophilic anaerobic digestion of chicken manure: Microbial community dynamics and process resilience

    International Nuclear Information System (INIS)

    Highlights: • Microbial community dynamics and process functional resilience were investigated. • The threshold of TAN in mesophilic reactor was higher than the thermophilic reactor. • The recoverable archaeal community dynamic sustained the process resilience. • Methanosarcina was more sensitive than Methanoculleus on ammonia inhibition. • TAN and FA effects the dynamic of hydrolytic and acidogenic bacteria obviously. - Abstract: While methane fermentation is considered as the most successful bioenergy treatment for chicken manure, the relationship between operational performance and the dynamic transition of archaeal and bacterial communities remains poorly understood. Two continuous stirred-tank reactors were investigated under thermophilic and mesophilic conditions feeding with 10%TS. The tolerance of thermophilic reactor on total ammonia nitrogen (TAN) was found to be 8000 mg/L with free ammonia (FA) 2000 mg/L compared to 16,000 mg/L (FA1500 mg/L) of mesophilic reactor. Biomethane production was 0.29 L/gV Sin in the steady stage and decreased following TAN increase. After serious inhibition, the mesophilic reactor was recovered successfully by dilution and washing stratagem compared to the unrecoverable of thermophilic reactor. The relationship between the microbial community structure, the bioreactor performance and inhibitors such as TAN, FA, and volatile fatty acid was evaluated by canonical correspondence analysis. The performance of methanogenic activity and substrate removal efficiency were changed significantly correlating with the community evenness and phylogenetic structure. The resilient archaeal community was found even after serious inhibition in both reactors. Obvious dynamics of bacterial communities were observed in acidogenic and hydrolytic functional bacteria following TAN variation in the different stages

  18. Trends in occurrence of thermophilous dragonfly species in North Rhine-Westphalia (NRW

    Directory of Open Access Journals (Sweden)

    Klaus-Jürgen Conze

    2010-12-01

    Full Text Available Since 1996 the “Workgroup Odonata in North Rhine-Westphalia” (“AK Libellen NRW” has built up a data base including about 150.000 data sets concerning the occurrence of dragonflies in North Rhine-Westphalia (NRW. This data confirms an increase and spread of some thermophilous dragonfly species in NRW, and the effects of climate change evidenced by an increasing average temperature, are considered to be important reasons for this process.

  19. High stability of apo-cytochrome c' from thermophilic Hydrogenophilus thermoluteolus.

    Science.gov (United States)

    Fujii, Sotaro; Masanari, Misa; Yamanaka, Masaru; Wakai, Satoshi; Sambongi, Yoshihiro

    2014-01-01

    Apo-cytochomes c without heme are usually unstructured. Here we showed that apo-form of thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) was a monomeric protein with high helix content. Apo-PHCP was thermally stable, possibly due to the hydrophobic residues and ion pairs. PHCP is the first example of a structured apo-cytochrome c', which will expand our view of hemoprotein structure formation.

  20. Upflow anaerobic solid-state (UASS) digestion of horse manure: Thermophilic vs. mesophilic performance.

    Science.gov (United States)

    Böske, Janina; Wirth, Benjamin; Garlipp, Felix; Mumme, Jan; Van den Weghe, Herman

    2015-01-01

    Energetic use of complex lignocellulosic wastes has gained global interest. Thermophilic digestion of horse manure based on straw was investigated using the upflow anaerobic solid-state (UASS) process. Increasing the organic loading rate from 2.5 to 5.5gvsL(-)(1)d(-)(1) enhanced the average methane production rate from 0.387 to 0.687LCH4L(-)(1)d(-)(1), whereas the yield decreased from 154.8 to 124.8LCH4kgvs(-)(1). A single-stage and two-stage process design showed almost the same performance. Compared to prior experiments at mesophilic conditions, thermophilic conditions showed a significantly higher efficiency with an increase of 59.8% in methane yield and 58.1% in methane production rate. Additional biochemical methane potential (BMP) tests with two types of horse manure and four different bedding materials showed that wheat straw obtained the highest BMP. The results show that the thermophilic UASS process can be the key to an efficient energy recovery from straw-based manures.

  1. Genetics of thermophilic bacteria: Progress report, May 1, 1986--June 30, 1988

    Energy Technology Data Exchange (ETDEWEB)

    Welker, N.E.

    1988-01-01

    Efficient and reliable protoplasting, regeneration and fusion techniques have been established for a prototrophic strain of Bacillus stearothermophilus. A variety of auxotrophic mutants and a restriction-deficient mutant were isolated and protoplast fusion was used to construct isogenic strains and for chromosomal mapping. Two linkage groups (hom thr and his gly pur-1) were established using this system. The order of the markers is similar to analagous markers on the Bacillus subtilis chromosome. We have evidence that this genetic exchange system can be used for linear chromosomal DNA transformation of protoplasts. Investigations have recently been initiated to develop a transducing system in this strain. Attempts to introduce a thermophile plasmid into strain NUB36 by transformation of protoplasts or protoplast fusion were unsuccessful. We think that the lack of success encountered in these studies is because this plasmid is not stably maintained at high temperature and/or is incompatible with the cryptic plasmids contained in this strain. This is the first report of a reliable genetic exchange system in B. stearothermophilus. This system can be used for the genetic analysis of this organism and for molecular cloning. The development of a host-vector system for cloning in B. stearothermophilus will make it possible to clone genes encoding cellulose hydrolysis, alcohol formation, or methane production. In addition, information gained from the genetic analysis of thermophilic bacilli may be of value in developing genetic systems in thermophilic eubacteria and archaebacteria. 3 tabs.

  2. Comparing mesophilic and thermophilic anaerobic digestion of chicken manure: Microbial community dynamics and process resilience.

    Science.gov (United States)

    Niu, Qigui; Takemura, Yasuyuki; Kubota, Kengo; Li, Yu-You

    2015-09-01

    While methane fermentation is considered as the most successful bioenergy treatment for chicken manure, the relationship between operational performance and the dynamic transition of archaeal and bacterial communities remains poorly understood. Two continuous stirred-tank reactors were investigated under thermophilic and mesophilic conditions feeding with 10%TS. The tolerance of thermophilic reactor on total ammonia nitrogen (TAN) was found to be 8000mg/L with free ammonia (FA) 2000mg/L compared to 16,000mg/L (FA1500mg/L) of mesophilic reactor. Biomethane production was 0.29 L/gVSin in the steady stage and decreased following TAN increase. After serious inhibition, the mesophilic reactor was recovered successfully by dilution and washing stratagem compared to the unrecoverable of thermophilic reactor. The relationship between the microbial community structure, the bioreactor performance and inhibitors such as TAN, FA, and volatile fatty acid was evaluated by canonical correspondence analysis. The performance of methanogenic activity and substrate removal efficiency were changed significantly correlating with the community evenness and phylogenetic structure. The resilient archaeal community was found even after serious inhibition in both reactors. Obvious dynamics of bacterial communities were observed in acidogenic and hydrolytic functional bacteria following TAN variation in the different stages. PMID:26054964

  3. Enhancing ethanol production from thermophilic and mesophilic solid digestate using ozone combined with aqueous ammonia pretreatment.

    Science.gov (United States)

    Wang, Dianlong; Xi, Jiang; Ai, Ping; Yu, Liang; Zhai, Hong; Yan, Shuiping; Zhang, Yanlin

    2016-05-01

    Pretreatment with ozone combined with aqueous ammonia was used to recover residual organic carbon from recalcitrant solid digestate for ethanol production after anaerobic digestion (AD) of rice straw. Methane yield of AD at mesophilic and thermophilic conditions, and ethanol production of solid digestate were investigated. The results showed that the methane yield at thermophilic temperature was 72.2% higher than that at mesophilic temperature under the same conditions of 24days and 17% solid concentration. And also the ethanol production efficiency of solid digestate after thermophilic process was 24.3% higher than that of solid digestate after mesophilic process. In this study, the optimal conditions for integrated methane and ethanol processes were determined as 55°C, 17% solid concentration and 24days. 58.6% of glucose conversion, 142.8g/kg of methane yield and 65.2g/kg of ethanol yield were achieved, and the highest net energy balance was calculated as 6416kJ/kg.

  4. Mineralization of a Proterozoic Sulfide Black Smoker Chimney and Thermophilous Microorganisms in Eastern Hebei, China

    Institute of Scientific and Technical Information of China (English)

    XIA Xuehui; LIAN Wei; YUAN Congjian; YAN Fei; YUAN Jiazhong

    2008-01-01

    A sulfide black smoker chimney exists in the Gaobanhe seabed exhalation massive sulfidedeposit in the Xinglong-Kuancheng secondary fault basin of the Proterozoic Yanliao rift trough inHebei Province, taking the shape of mounds, individually about 2-3 cm high. Abundant fossils ofthermophilous bacteria and algae in perfect preservation are found in the ore surrounding the blacksmoker chimney. Scanning electron microscopy (SEM) and molecular biomarker studies on themicroorganismal ore fabric show that the microorganism in the sulfide ore is in fact a sedimentaryproduct of probiotic bacteria and algae. In the special food chain based on black smoker chimney atancient seabed- thermophilous bacteria, the thermophilons bacteria and algae reproduce in largequantity. Intermittently erupting of fluid from the chimney creats conditions for formation of sulfidedeposit. In the process of exhalation action of hot fluid, thermophilous bacteria and algae grow andreproduce around the sulfide black smoker chimney, absorbing mineralizing substances brought bythe fluid. Massive sulfide deposits are formed in this process of absorption of seabed black smokerchimney exhalation-mineralizing fluid puisation.thermophilous microorganism.

  5. Investigating the potential of thermophilic species for ethanol production from industrial spent sulfite liquor

    Directory of Open Access Journals (Sweden)

    Michaela Weissgram

    2015-10-01

    Full Text Available Thermophilic microorganisms hold a great potential for bioethanol production on waste biomass, due to their ability to utilize pentoses and hexoses alike. However, to date hardly any data on thermophiles growing directly on industrial substrates like spent sulfite liquor (SSL are available. This contribution investigates the ability of Thermoanaerobacter species to utilize the main sugars in the used SSL (mannose, glucose and xylose and the effect of process parameters (pH, temperature and sugar concentration on their growth. Based on these results the strain T. mathranii was chosen for further studies. The ability of T. mathranii to grow directly on SSL was investigated and the effect of several inhibiting substances on growth was elucidated. Furthermore it was tested whether pretreatment with activated charcoal can increase the fermentability of SSL. The fermentations were evaluated based on yields and specific rates. It could be shown that T. mathranii was able to ferment all sugars in the investigated softwood SSL and fermented diluted, untreated SSL (up to 2.7% (w/w dry matter. Pretreatment with activated charcoal could slightly reduce the amount of phenols in the substrate and thus facilitate growth and ethanol production on higher SSL concentrations (up to 4.7% (w/v dry matter. Ethanol yields of 0.29-0.44 Cmmol of ethanol per Cmmol sugar were obtained on untreated and pretreated spent sulfite liquor, respectively. These results on an industrial substrate strengthen the claim that thermophilic microorganisms might be the optimal candidates for forest biorefinery.

  6. Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria

    Science.gov (United States)

    Kanazawa, S.; Ishikawa, Y.; Tomita-Yokotani, K.; Hashimoto, H.; Kitaya, Y.; Yamashita, M.; Nagatomo, M.; Oshima, T.; Wada, H.; Space Agriculture Task Force, J.

    Manned Mars exploration requires recycle of materials to support human life A conceptual design is developed for space agriculture which is driven by the biologically regenerative function Hyper-thermophilic aerobic composting bacterial ecology is the core of materials recycling system to process human metabolic waste and inedible biomass and convert them to fertilizer for plants cultivation A photosynthetic reaction of plants will be driven by solar energy Water will be recycled by cultivation of plants and passing it through plant bodies Sub-surface water and atmospheric carbon dioxide are the natural resource available on Mars and these resources will be converted to oxygen and foods We envision that the agricultural system will be scaled up by importing materials from Martian environment Excess oxygen will be obtained from growing trees for structural and other components Minor elements including N P K and other traces will be introduced as fertilizers or nutrients into the agricultural materials circulation Nitrogen will be collected from Martian atmosphere We will assess biological fixation of nitrogen using micro-organisms responsible in Earth biosphere Hyper-thermophilic aerobic bacterial ecology is effective to convert waste materials into useful forms to plants This microbial technology has been well established on ground for processing sewage and waste materials For instance the hyper-thermophilic bacterial system is applied to a composting machine in a size of a trash box in home kitchen Since such a home electronics

  7. Comparative microbiological-hygienic studies in mesophilic and thermophilic fouling of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Pohlig-Schmitt, M.; Philipp, W.; Wekerle, J.; Strauch, D.

    Investigations concerning the inactivation of microbial pathogens (bacteria, viruses and parasites) during anaerobic, alkaline dignestion of sludge are described. A thermophilic (54/sup 0/C) and a mesophilic (34/sup 0/C) operated biogas model plant were compared from the point of view of hygiene. Is was found that in the thermophilic process Salmonella senftenberg survived 13,5 h, Streptococcus faecium 55 h, Streptococcus faecalis 42 h and Klebsiella pneumoniae 0,5 h. Within 30 min eggs of Ascaris suum lost their infectivity Bovine Parvovirus was inactivated after 1 d to 2 d treatment. Survival times under mesophilic conditions of 13 d for Salmonella senftenberg and more than 8 mouth for Streptococcus faecium were found. Poliovirus Type 1 was inactivated in 8 d while Bovine Parvovirus survived no longer than 15 d. The results obtained in the thermophilic process were compared to those after heat treatment of the test microorganisms in ampules exposed in a wather-bath under defined conditions to 54/sup 0/C. It was found, that the bacteria survived only about half the time in this case. Poliovirus Type 1 was inactivated after 0,75 h and Bovine Parvovirus after 7 d exposure. (orig.RB)

  8. Characterization of a novel non-specific nuclease from thermophilic bacteriophage GBSV1

    Directory of Open Access Journals (Sweden)

    Zhang Xiaobo

    2008-04-01

    Full Text Available Abstract Background Thermostable enzymes from thermophiles have attracted extensive studies. In this investigation, a nuclease-encoding gene (designated as GBSV1-NSN was obtained from a thermophilic bacteriophage GBSV1 for the first time. Results After recombinant expression in Escherichia coli, the purified GBSV1-NSN exhibited non-specific nuclease activity, being able to degrade various nucleic acids, including RNA, single-stranded DNA and double-stranded DNA that was circular or linear. Based on sequence analysis, the nuclease shared no homology with any known nucleases, suggesting that it was a novel nuclease. The characterization of the recombinant GBSV1-NSN showed that its optimal temperature and pH were 60°C and 7.5, respectively. The results indicated that the enzymatic activity was inhibited by enzyme inhibitors or detergents, such as ethylene diamine tetraacetic acid, citrate, dithiothreitol, β-mercaptoethanol, guanidine hydrochloride, urea and SDS. In contrast, the nuclease activity was enhanced by TritonX-100, Tween-20 or chaps to approximately 124.5% – 141.6%. The Km of GBSV1-NSN nuclease was 231, 61 and 92 μM, while its kcat was 1278, 241 and 300 s-1 for the cleavage of dsDNA, ssDNA and RNA, respectively. Conclusion Our study, therefore, presented a novel thermostable non-specific nuclease from thermophilic bacteriophage and its overexpression and purification for scientific research and applications.

  9. Innovative two-stage mesophilic/thermophilic anaerobic degradation of sonicated sludge: performances and energy balance.

    Science.gov (United States)

    Gianico, A; Braguglia, C M; Gallipoli, A; Mininni, G

    2015-05-01

    This study investigates for the first time, on laboratory scale, the possible application of an innovative enhanced stabilization process based on sequential mesophilic/thermophilic anaerobic digestion of waste-activated sludge, with low-energy sonication pretreatment. The first mesophilic digestion step was conducted at short hydraulic retention time (3-5 days), in order to favor volatile fatty acid production, followed by a longer thermophilic step of 10 days to enhance the bioconversion kinetics, assuring a complete pathogen removal. The high volatile solid removals, up to 55%, noticeably higher compared to the performances of a single-stage process carried out in same conditions, can guarantee the stability of the final digestate for land application. The ultrasonic pretreatment influenced significantly the fatty acid formation and composition during the first mesophilic step, improving consequently the thermophilic conversion of these compounds into methane. Methane yield from sonicated sludge digestion reached values up to 0.2 Nm(3)/kgVSfed. Positive energy balances highlighted the possible exploitation of this innovative two-stage digestion in place of conventional single-stage processes. PMID:24906832

  10. Study of thermophilic anaerobic cleaning systems; Studier av termofila anaeroba reningssystem

    Energy Technology Data Exchange (ETDEWEB)

    Boman, B.; Davisson, G.

    1994-11-01

    The aim of this study was to indicate how mesophile and thermophilic anaerobic systems differ in their capacity to degrade persistent organic compounds. The experiments were carried out in semi-batch lab.scale reactors working at 35, 55 and 70 degrees C and were evaluated by recording pH, COD, TSS, redox potential, fatty acids, gas production, methane concentration and the concentration of specific organic compounds. Totally, seven different reactors and four different specific organic compounds were used in this study. The microbial activity within the semi-batch reactors showed a pronounced tendency to oscillate in an irregular and unpredictable way. This behaviour stressed the difficulties in running the decided experiments. These experiences are unfortunately confirmed by many other investigators within the present field. The results do not indicate differences between mesophile and thermophilic anaerobic reactors in terms of `not degradable-degradable` but only as differences in degree of degradation rates. 6-chlorovanillin and 3,5-dinitrobenzoic acid showed increasing degradation rate in the thermophilic range while no differences could be detected for 4,5-dichloroguaiacol. In the case of {beta}-sitosterol the mesophile reference reactor crash. 14 refs, 6 figs, 3 tabs

  11. Upflow anaerobic solid-state (UASS) digestion of horse manure: Thermophilic vs. mesophilic performance.

    Science.gov (United States)

    Böske, Janina; Wirth, Benjamin; Garlipp, Felix; Mumme, Jan; Van den Weghe, Herman

    2015-01-01

    Energetic use of complex lignocellulosic wastes has gained global interest. Thermophilic digestion of horse manure based on straw was investigated using the upflow anaerobic solid-state (UASS) process. Increasing the organic loading rate from 2.5 to 5.5gvsL(-)(1)d(-)(1) enhanced the average methane production rate from 0.387 to 0.687LCH4L(-)(1)d(-)(1), whereas the yield decreased from 154.8 to 124.8LCH4kgvs(-)(1). A single-stage and two-stage process design showed almost the same performance. Compared to prior experiments at mesophilic conditions, thermophilic conditions showed a significantly higher efficiency with an increase of 59.8% in methane yield and 58.1% in methane production rate. Additional biochemical methane potential (BMP) tests with two types of horse manure and four different bedding materials showed that wheat straw obtained the highest BMP. The results show that the thermophilic UASS process can be the key to an efficient energy recovery from straw-based manures. PMID:25459798

  12. A Numerical Evaluation on the Viability of Heap Thermophilic Bioleaching of Chalcopyrite

    Science.gov (United States)

    Vilcaez, J.; Suto, K.; Inoue, C.

    2007-03-01

    The present numerical evaluation explores into the interactions among the many variables governing the mass and heat transport processes that take place in a heap thermophilic bioleaching system. The necessity of using mesophiles together with thermophiles is proved by tracing the activity of both microorganisms individually at each point throughout the heap. The role of key variables such as the fraction of FeS2 per CuFeS2 leached was quantified and its importance highlighted. In this evaluation, the heat transfer process plays the main role because of the heat accumulation required to maintain the heap temperature within the range of 60 °C to 80 °C where thermophilic microorganisms are capable of completing the unfinished dissolution of copper started by mesophilic microorganisms at 30 °C. The evaluation was done taking into consideration: biological activity as function of the temperature in the heap, heat loss due to conduction and advection from the top and bottom of the heap, and mass transfer between the gas and liquid phases as a function of temperature. The exothermic nature of the leaching reactions of CuFeS2 and FeS2 makes the system auto-thermal.

  13. Enhancing ethanol production from thermophilic and mesophilic solid digestate using ozone combined with aqueous ammonia pretreatment.

    Science.gov (United States)

    Wang, Dianlong; Xi, Jiang; Ai, Ping; Yu, Liang; Zhai, Hong; Yan, Shuiping; Zhang, Yanlin

    2016-05-01

    Pretreatment with ozone combined with aqueous ammonia was used to recover residual organic carbon from recalcitrant solid digestate for ethanol production after anaerobic digestion (AD) of rice straw. Methane yield of AD at mesophilic and thermophilic conditions, and ethanol production of solid digestate were investigated. The results showed that the methane yield at thermophilic temperature was 72.2% higher than that at mesophilic temperature under the same conditions of 24days and 17% solid concentration. And also the ethanol production efficiency of solid digestate after thermophilic process was 24.3% higher than that of solid digestate after mesophilic process. In this study, the optimal conditions for integrated methane and ethanol processes were determined as 55°C, 17% solid concentration and 24days. 58.6% of glucose conversion, 142.8g/kg of methane yield and 65.2g/kg of ethanol yield were achieved, and the highest net energy balance was calculated as 6416kJ/kg. PMID:26868156

  14. Potential use of thermophilic dark fermentation effluents in photofermentative hydrogen production by Rhodobacter capsulatus

    Energy Technology Data Exchange (ETDEWEB)

    Ozgura, E.; Afsar, N.; Eroglu, I. [Middle East Technical University, Department of Chemical Engineering, 06531 Ankara (Turkey); De Vrije, T.; Claassen, P.A.M. [Wageningen UR, Agrotechnology and Food Sciences Group, Wageningen UR, P.O. Box 17, 6700 AA Wageningen (Netherlands); Yucel, M.; Gunduz, U. [Middle East Technical University, Department of Biology, 06531 Ankara (Turkey)

    2010-12-15

    Biological hydrogen production by a sequential operation of dark and photofermentation is a promising route to produce hydrogen. The possibility of using renewable resources, like biomass and agro-industrial wastes, provides a dual effect of sustainability in biohydrogen production and simultaneous waste removal. In this study, photofermentative hydrogen production on effluents of thermophilic dark fermentations on glucose, potato steam peels (PSP) hydrolysate and molasses was investigated in indoor, batch operated bioreactors. An extreme thermophile Caldicellulosiruptor saccharolyticus was used in the dark fermentation step, and Rhodobacter capsulatus (DSM1710) was used in the photofermentation step. Addition of buffer, Fe and Mo to dark fermentor effluents (DFEs) improved the overall efficiency of hydrogen production. The initial acetate concentration in the DFE needed to be adjusted to 30-40 mM by dilution to increase the yield of hydrogen in batch light-supported fermentations. The thermophilic DFEs are suitable for photofermentative hydrogen production, provided that they are supplemented with buffer and nutrients. The overall hydrogen yield of the two-step fermentations was higher than the yield of single step dark fermentations.

  15. Screening of thermotolerant and thermophilic fungi aiming β-xylosidase and arabinanase production

    Directory of Open Access Journals (Sweden)

    Vivian Machado Benassi

    2014-12-01

    Full Text Available Plant cell wall is mainly composed by cellulose, hemicellulose and lignin. The heterogeneous structure and composition of the hemicellulose are key impediments to its depolymerization and subsequent use in fermentation processes. Thus, this study aimed to perform a screening of thermophilic and thermotolerant filamentous fungi collected from different regions of the São Paulo state, and analyze the production of β-xylosidase and arabinanase at different temperatures. These enzymes are important to cell wall degradation and synthesis of end products as xylose and arabinose, respectively, which are significant sugars to fermentation and ethanol production. A total of 12 fungal species were analyzed and 9 of them grew at 45 ºC, suggesting a thermophilic or thermotolerant character. Additionally Aspergillus thermomutatus anamorph of Neosartorya and A. parasiticus grew at 50 ºC. Aspergillus niger and Aspergillus thermomutatus were the filamentous fungi with the most expressive production of β-xylosidase and arabinanase, respectively. In general for most of the tested microorganisms, β-xylosidase and arabinanase activities from mycelial extract (intracellular form were higher in cultures grown at high temperatures (35-40 ºC, while the correspondent extracellular activities were favorably secreted from cultures at 30 ºC. This study contributes to catalogue isolated fungi of the state of São Paulo, and these findings could be promising sources for thermophilic and thermotolerant microorganisms, which are industrially important due to their enzymes.

  16. Proteins responsible for lysogeny of deep-sea thermophilic bacteriophage GVE2 at high temperature.

    Science.gov (United States)

    Song, Qing; Ye, Ting; Zhang, Xiaobo

    2011-06-15

    The lytic and lysogenic life cycle switch of bacteriophages plays very important roles in virus-host interactions. However, the lysogeny of thermophilic bacteriophage infecting thermophile at high temperatures has not been addressed. In this study, two lysogeny-related genes encoding the CI protein and recombinase of GVE2, a thermophilic bacteriophage obtained from a deep-sea hydrothermal vent, were characterized. Temporal analyses showed that the two genes were expressed at early stages of GVE2 infection. Based on chromatin immunoprecipitation (ChIP) assay and electrophoretic mobility shift assay (EMSA), the GVE2 CI protein was bound with only one DNA fragment located at 24264-24036 bp in the GVE2 genome. This location might be the original transcription site and the lysis-lysogeny switch site, which was very different from mesophilic bacteriophages. The GVE2 CI and recombinase proteins could function only at high temperatures. Therefore our study improved our understanding of the lysogeny process of bacteriophages at high temperatures. PMID:21303688

  17. Start-up performances of dry anaerobic mesophilic and thermophilic digestions of organic solid wastes

    Institute of Scientific and Technical Information of China (English)

    LU Shu-guang; IMAI Tsuyoshi; UKITA Masao; SEKINE Masahiko

    2007-01-01

    Two dry anaerobic digestions of organic solid wastes were conducted for 6 weeks in a lab-scale batch experiment for investigating the start-up performances under mesophilic and thermophilic conditions. The enzymatic activities,i.e., β-glucosidase, β-glucosidase, N-α -benzoyl-L-argininamide (BAA)-hydrolysing protease, urease and phosphatase activities were analysed. The lower BAA-hydrolysing protease activity during the first 2-3 weeks was due to the inhibition of the low pH, but was enhanced simultaneously later with the pH increase. β-glucosidase activity showed the lowest values in weeks 1-2, and recovered simultaneously with the increase of BAA-hydrolysing protease activity. Acetic acid dominated most of the total VFAs in thermophilic digestion, while propionate and butyrate dominated in mesophilic digestion. Thermophilic digestion is confirmed more feasible for achieving better performance against misbalance, especially during the start-up period in a dry anaerobic digestion process.

  18. Developing a thermophilic hydrogen-producing co-culture for efficient utilization of mixed sugars

    Energy Technology Data Exchange (ETDEWEB)

    Zeidan, Ahmad A.; Van Niel, Ed W.J. [Department of Applied Microbiology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden)

    2009-05-15

    Previous studies on the extreme thermophile Caldicellulosiruptor saccharolyticus revealed that the organism produces high yields of hydrogen on glucose and xylose, the major components of lignocellulosic hydrolysates. Preliminary experiments on mixed sugar substrates, however, indicated that xylose was preferred over glucose. The sugar preference of some other extreme thermophiles, including Caldicellulosiruptor owensensis, Caldicellulosiruptor kristjanssonii and newly enriched, thermophilic compost sludge microflora, was investigated in an attempt to find complementary organisms to C. saccharolyticus for rapid and efficient utilization of lignocellulosic sugars. The behavior of C. owensensis and C. kristjanssonii appeared to be similar to that of C. saccharolyticus, either in pure cultures or in co-cultures with the latter. Co-culturing C. saccharolyticus with the enriched compost microflora resulted in fast, simultaneous consumption of both glucose and xylose in the medium with a relatively high specific hydrogen production rate, 40 mmol (gCDW){sup -1} h{sup -1}, and high volumetric productivity, 22.5 mmol l{sup -1} h{sup -1}. (author)

  19. High-solids enrichment of thermophilic microbial communities and their enzymes on bioenergy feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A. P.; Allgaier, M.; Singer, S.W.; Hazen, T.C.; Simmons, B.A.; Hugenholtz, P.; VanderGheynst, J.S.

    2011-04-01

    Thermophilic microbial communities that are active in a high-solids environment offer great potential for the discovery of industrially relevant enzymes that efficiently deconstruct bioenergy feedstocks. In this study, finished green waste compost was used as an inoculum source to enrich microbial communities and associated enzymes that hydrolyze cellulose and hemicellulose during thermophilic high-solids fermentation of the bioenergy feedstocks switchgrass and corn stover. Methods involving the disruption of enzyme and plant cell wall polysaccharide interactions were developed to recover xylanase and endoglucanase activity from deconstructed solids. Xylanase and endoglucanase activity increased by more than a factor of 5, upon four successive enrichments on switchgrass. Overall, the changes for switchgrass were more pronounced than for corn stover; solids reduction between the first and second enrichments increased by a factor of four for switchgrass while solids reduction remained relatively constant for corn stover. Amplicon pyrosequencing analysis of small-subunit ribosomal RNA genes recovered from enriched samples indicated rapid changes in the microbial communities between the first and second enrichment with the simplified communities achieved by the third enrichment. The results demonstrate a successful approach for enrichment of unique microbial communities and enzymes active in a thermophilic high-solids environment.

  20. Differential expression of extracellular thiol groups of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on S(0) and Fe (2.).

    Science.gov (United States)

    Liu, Hong-Chang; Xia, Jin-Lan; Nie, Zhen-Yuan; Zhen, Xiang-Jun; Zhang, Li-Juan

    2015-08-01

    Bio-oxidation of elemental sulfur (S(0)) is very important in bioleaching and sulfur cycle. S(0) was proposed to be first activated by reacting with reactive thiol groups (-SH) of outer membrane proteins, forming -S n H (n ≥ 2) complexes. The differential expression of -SH of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on Fe(2+) and S(0) was investigated by synchrotron radiation-based scanning transmission X-ray microscopy (STXM) imaging and micro-beam X-ray fluorescence (μ-XRF) mapping. The STXM imaging and μ-XRF mapping of extracellular -SH were based on the analysis of Ca(2+) bound on the cell. By comparing Ca(2+) of the cells with and without labeling by Ca(2+), the distribution and content of thiol groups were obtained. The results showed that, for both S. thermosulfidooxidans and A. manzaensis, the expression of extracellular -SH of S(0)-grown cells was higher than that of Fe(2+)-grown cells. Statistical analysis indicated that the expression of extracellular -SH for S. thermosulfidooxidans and A. manzaensis grown on S(0) was 2.37 times and 2.14 times, respectively, to that on Fe(2+). These results evidently demonstrate that the extracellular thiol groups are most probably involved in elemental sulfur activation and oxidation of the acidophilic sulfur-oxidizing microorganisms. PMID:25983134

  1. Differential expression of extracellular thiol groups of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on S(0) and Fe (2.).

    Science.gov (United States)

    Liu, Hong-Chang; Xia, Jin-Lan; Nie, Zhen-Yuan; Zhen, Xiang-Jun; Zhang, Li-Juan

    2015-08-01

    Bio-oxidation of elemental sulfur (S(0)) is very important in bioleaching and sulfur cycle. S(0) was proposed to be first activated by reacting with reactive thiol groups (-SH) of outer membrane proteins, forming -S n H (n ≥ 2) complexes. The differential expression of -SH of moderately thermophilic Sulfobacillus thermosulfidooxidans and extremely thermophilic Acidianus manzaensis grown on Fe(2+) and S(0) was investigated by synchrotron radiation-based scanning transmission X-ray microscopy (STXM) imaging and micro-beam X-ray fluorescence (μ-XRF) mapping. The STXM imaging and μ-XRF mapping of extracellular -SH were based on the analysis of Ca(2+) bound on the cell. By comparing Ca(2+) of the cells with and without labeling by Ca(2+), the distribution and content of thiol groups were obtained. The results showed that, for both S. thermosulfidooxidans and A. manzaensis, the expression of extracellular -SH of S(0)-grown cells was higher than that of Fe(2+)-grown cells. Statistical analysis indicated that the expression of extracellular -SH for S. thermosulfidooxidans and A. manzaensis grown on S(0) was 2.37 times and 2.14 times, respectively, to that on Fe(2+). These results evidently demonstrate that the extracellular thiol groups are most probably involved in elemental sulfur activation and oxidation of the acidophilic sulfur-oxidizing microorganisms.

  2. The Distribution of Thermophilic Sulfate-reducing Bacteria Along an Estuarine Gradient Reveals Multiple Origins of Endospores in Estuarine Sediments

    Science.gov (United States)

    Bell, E.

    2015-12-01

    Cold marine sediments harbour inactive spores of thermophilic bacteria. These misplaced thermophiles are genetically similar to microorganisms detected in deep biosphere environments, leading to the hypothesis that seabed fluid flow transports thermophiles out of warm subsurface environments and into the ocean. Estuaries form the transition between the marine and the terrestrial biosphere and are influenced by tidal currents, surface run-off and groundwater seepage. Endospores from thermophilic bacteria present in estuarine sediments could therefore originate from a number of sources that may influence the estuary differently. We have therefore tested the hypothesis that this will lead to a gradient in the composition of thermophilic endospore populations in estuarine sediments. The distribution of thermophilic spore-forming sulfate-reducing bacteria along an estuarine gradient from freshwater (River Tyne, UK) to marine (North Sea) was investigated. Microbial community analysis by 16S rRNA gene amplicon sequencing revealed changes in the thermophilic population enriched at different locations within the estuary. Certain species were only detected at the marine end, highlighting possible links to deep marine biosphere habitats such as oil reservoirs that harbour closely related Desulfotomaculum spp. Conversely, other taxa were predominantly observed in the freshwater reaches of the estuary indicating dispersal from an upstream or terrestrial source. Different endospore populations were enriched dependent on incubation temperature and spore heat-resistance. Microcosms incubated at 50, 60 or 70°C showed a shift in the dominant species of Desulfotomaculum enriched as the temperature increased. Microcosms triple-autoclaved at 121°C prior to incubation still showed rapid and reproducible sulfate-reduction and some Desulfotomaculum spp. remained active after autoclaving at 130°C. These results show that temperature physiology and biogeographic patterns can be used to

  3. Investigations on potato pulp as a dietary fiber source. The influence of pectolytic and cellulolytic enzymes. Untersuchungen an Kartoffelpuelpe als Ballaststoffquelle. Zum Einfluss von pektolytischen und cellulolytischen Enzymen

    Energy Technology Data Exchange (ETDEWEB)

    Dongowski, G. (Deutsches Inst. fuer Ernaehrungsforschung Potsdam-Rehbruecke, Bergholz-Rehbruecke (Germany))

    1993-05-01

    The influence of treatment with pectolytic and cellulolytic enzyme preparations was investigated with reference to the separation of water and the composition of potato pulp. In contrast to pectinesterase, pectate lyase or cellulase it was found an intensive action on the pulp after incubation with Pectinex Ultra SP-L or pectinase/cellulase combinations. The content of pectin, starch and protein as well as the water binding capacity are varied in dependence of the used enzyme preparations. The occurring changes in the supermolecular structure of the potato pulp tissue are investigated by scanning electron microscopy. The grown biological structure is partly or extensive destroyed especially after action of pectinases and cellulases. The content of starch in the potato pulp preparations remains relatively high even after intensive treatment with cell wall degrading enzymes. (orig.)

  4. [Display cellulolytic enzymes on Saccharomyces cerevisiae cell surface by using Flo1p as an anchor protein for cellulosic ethanol production].

    Science.gov (United States)

    Mo, Chunling; Yang, Yueyue; Chen, Ning; Yang, Xiushan; Tian, Shen

    2014-09-01

    In this study, we constructed a yeast consortium surface-display expression system by using Flo1 as an anchor protein. Endoglucanase II (EGII) and cellobiohydrolase II (CBHII) from Trichoderma reesei, and β3-glucosidase 1 (BGLI) from Aspergillus aculeatus were immobilized on Saccharomyces cerevisiae Y5. We constructed the cellulose-displaying expression yeast consortium (Y5/fEGII:Y5/fCBHII:Y5/fBGLI = 1:1:1) and investigated the enzymatic ability and ethanol fermentation. The displayed cellulolytic enzymes was stabile during the 96-h fermentation. The yeast consortium produced 0.77 g/L ethanol from 10 g/L phosphoric acid swollen cellulose (PASC) within 96 h. The yield (in grams of ethanol produced per gram of carbohydrate consumed) was 0.35 g/g, which correspond to 68.6% of the theoretical yield. PMID:25720155

  5. Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria

    Science.gov (United States)

    Space Agriculture Task Force; Ishikawa, Y.; Tomita-Yokotani, K.; Hashimoto, H.; Kitaya, Y.; Yamashita, M.; Nagatomo, M.; Oshima, T.; Wada, H.

    Manned Mars exploration, especially for extended periods of time, will require recycle of materials to support human life. Here, a conceptual design is developed for a Martian agricultural system driven by biologically regenerative functions. One of the core biotechnologies function is the use of hyper-thermophilic aerobic composting bacterial ecology. These thermophilic bacteria can play an important role in increasing the effectiveness of the processing of human metabolic waste and inedible biomass and of converting them to fertilizer for the cultivation of plants. This microbial technology has been already well established for the purpose of processing sewage and waste materials for small local communities in Japan. One of the characteristics of the technology is that the metabolic heat release that occurs during bacterial fermentation raises the processing temperature sufficiently high at 80 100 °C to support hyper-thermophilic bacteria. Such a hyper-thermophilic system is found to have great capability of decomposing wastes including even their normally recalcitrant components, in a reasonably short period of time and of providing a better quality of fertilizer as an end-product. High quality compost has been shown to be a key element in creating a healthy regenerative food production system. In ground-based studies, the soil microbial ecology after the addition of high quality compost was shown to improve plant growth and promote a healthy symbiosis of arbuscular mycorrhizal fungi. Another advantage of such high processing temperature is the ability to sterilize the pathogenic organisms through the fermentation process and thus to secure the hygienic safety of the system. Plant cultivation is one of the other major systems. It should fully utilize solar energy received on the Martian surface for supplying energy for photosynthesis. Subsurface water and atmospheric carbon dioxide mined on Mars should be also used in the plant cultivation system. Oxygen and

  6. Activity-based protein profiling of secreted cellulolytic enzyme activity dynamics in Trichoderma reesei QM6a, NG14, and RUT-C30

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Lindsey N.; Culley, David E.; Hofstad, Beth A.; Chauvigne-Hines, Lacie M.; Zink, Erika M.; Purvine, Samuel O.; Smith, Richard D.; Callister, Stephen J.; Magnuson, Jon M.; Wright, Aaron T.

    2013-12-01

    Development of alternative, non-petroleum based sources of bioenergy that can be applied in the short-term find great promise in the use of highly abundant and renewable lignocellulosic plant biomass.1 This material obtained from different feedstocks, such as forest litter or agricultural residues, can yield liquid fuels and other chemical products through biorefinery processes.2 Biofuels are obtained from lignocellulosic materials by chemical pretreatment of the biomass, followed by enzymatic decomposition of cellulosic and hemicellulosic compounds into soluble sugars that are converted to desired chemical products via microbial metabolism and fermentation.3, 4 To release soluble sugars from polymeric cellulose multiple enzymes are required, including endoglucanase, exoglucanase, and β-glucosidase.5, 6 However, the enzymatic hydrolysis of cellulose into soluble sugars remains a significant limiting factor to the efficient and economically viable utilization of lignocellulosic biomass for transport fuels.7, 8 The primary industrial source of cellulose and hemicellulases is the mesophilic soft-rot fungus Trichoderma reesei,9 having widespread applications in food, feed, textile, pulp, and paper industries.10 The genome encodes 200 glycoside hydrolases, including 10 cellulolytic and 16 hemicellulolytic enzymes.11 The hypercellulolytic catabolite derepressed strain RUT-C30 was obtained through a three-step UV and chemical mutagenesis of the original T. reesei strain QM6a,12, 13 in which strains M7 and NG14 were intermediate, having higher cellulolytic activity than the parent strain but less activity and higher catabolite repression than RUT-C30.14 Numerous methods have been employed to optimize the secreted enzyme cocktail of T. reesei including cultivation conditions, operational parameters, and mutagenesis.3 However, creating an optimal and economical enzyme mixture for production-scale biofuels synthesis may take thousands of experiments to identify.

  7. Effects of Neutral Detergent Soluble Fiber and Sucrose Supplementation on Ruminal Fermentation, Microbial Synthesis, and Populations of Ruminal Cellulolytic Bacteria Using the Rumen Simulation Technique (RUSITEC)

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiang-hui; LIU Chan-juan; LI Chao-yun; YAO Jun-hu

    2013-01-01

    We evaluated the effects of neutral detergent soluble fiber (NDSF) and sucrose supplementation on ruminal fermentation, microbial synthesis, and populations of ruminal cellulolytic bacteria using the rumen simulation technique (RUSITEC). The experiment had a 2×2 factorial design with two dosages of sucrose, low (ca. 0.26 g d-1, low-sucrose) and high (ca. 1.01 g d-1, high-sucrose), and two dosages of supplied NDSF, low (1.95 g d-1, low-NDSF) and high (2.70 g d-1, high-NDSF). Interactions between NDSF and sucrose were detected for xylanase activity from solid fraction and apparent disappearance of neutral detergent fiber (NDF) and hemicellulose, with the lowest values observed for high-NDSF and high-sucrose treatment. Supplemental NDSF appeared to increase the molar proportion of acetate and reduce that of butyrate;however, the effects of supplemental sucrose on VFA profiles depended upon NDSF amount. There was a NDSF×sucrose interaction for the production of methane. High-NDSF fermenters had lower ammonia-N production, greater daily N flow of solid-associated microbial pellets and total microorganisms, and greater microbial synthesis efficiency compared with low-NDSF fermenters. Supplementation with NDSF resulted in an increase in 16S rDNA copies of Ruminococcus flavefaciens and a reduction in copies of Ruminococcus albus. Supplementation with sucrose tended to increase the 16S rDNA copies of R. albus from liquid fraction, but did not affect daily total microbial N flow and cellulolytic bacterium populations from solid fraction. These data indicate that the effects of the interaction between NDSF and sugars on ruminal fermentation and fiber digestion should be taken into account in diet formulation. Ruminal fermentation and metabolism of sugars warrant further investigation.

  8. Fate of selected emerging micropollutants during mesophilic, thermophilic and temperature co-phased anaerobic digestion of sewage sludge.

    Science.gov (United States)

    Samaras, Vasilios G; Stasinakis, Athanasios S; Thomaidis, Nikolaos S; Mamais, Daniel; Lekkas, Themistokles D

    2014-06-01

    The removal of endocrine disrupting compounds (EDCs) and non-steroidal anti-inflammatory drugs (NSAIDs) was studied in three lab-scale anaerobic digestion (AD) systems; a single-stage mesophilic, a single-stage thermophilic and a two-stage thermophilic/mesophilic. All micropollutants underwent microbial degradation. High removal efficiency (>80%) was calculated for diclofenac, ibuprofen, naproxen and ketoprofen; whereas triclosan, bisphenol A and the sum of nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenol diethoxylate were moderately removed (40-80%). NSAIDs removal was not affected by the type of AD system used; whereas slightly higher EDCs removal was observed in two-stage system. In this system, most microcontaminants were removed in thermophilic digester. Biotransformation of NP1EO and NP was affected by the temperature applied to bioreactors. Under mesophilic conditions, higher removal of NP1EO and accumulation of NP was noticed; whereas the opposite was observed under thermophilic conditions. For most analytes, higher specific removal rates were calculated under thermophilic conditions and 20 days SRT. PMID:24768891

  9. Semi-continuous solid substrate anaerobic reactors for H{sub 2} production from organic waste: Mesophilic versus thermophilic regime

    Energy Technology Data Exchange (ETDEWEB)

    Valdez-Vazquez, Idania; Rios-Leal, Elvira; Esparza-Garcia, Fernando; Poggi-Varaldo, Hector M. [CINVESTAV-IPN, Department Biotechnology and Bioengineering, Environmental Biotechnology, P.O. Box 14-740, Mexico D.F. 07000 (Mexico); Cecchi, Franco [Universita degli Studi di Verona, Verona (Italy)

    2005-11-01

    We evaluated the influence of the operation temperature (mesophilic vs. thermophilic regime) of semicontinuous, acidogenic solid substrate anaerobic digestion (A-SSAD) of the organic fraction of municipal solid waste (OFMSW) at lab scale. The H{sub 2} percentage was higher in the thermophilic regime than in the mesophilic operation (58% and 42%, respectively). The H{sub 2} yield of thermophilic A-SSAD was significantly higher than in our mesophilic reactors (360 vs. 165NmL H{sub 2}/g VS{sub rem}) and other studies reported in the literature (range of 62-180mL/g VS). Mesophilic A-SSAD showed a yield of 37% of the maximum yield based on 4molH{sub 2}/mol hexose, while thermophilic A-SSAD exhibited a yield of 80% of the maximum yield. This result is similar to works with pure cultures of extremophile microorganisms where H{sub 2} yields of 83% of the maximum were reported. We found higher concentrations of acetic acid in the digestates of thermophilic A-SSAD, while butyrate was in higher proportion in mesophilic A-SSAD spent solids. The moderate-to-high yields obtained with the semicontinuous process used in this work are in disagreement with previous reports claiming that batch and semicontinuous processes are less efficient than continuous ones. (author)

  10. Draft Genome Sequence of Geobacillus subterraneus Strain K, a Hydrocarbon-Oxidizing Thermophilic Bacterium Isolated from a Petroleum Reservoir in Kazakhstan

    Science.gov (United States)

    Poltaraus, Andrey B.; Sokolova, Diyana S.; Grouzdev, Denis S.; Ivanov, Timophey M.; Malakho, Sophia G.; Korshunova, Alena V.; Tourova, Tatiyana P.

    2016-01-01

    The draft genome sequence of Geobacillus subterraneus strain K, a thermophilic aerobic oil-oxidizing bacterium isolated from production water of the Uzen high-temperature oil field in Kazakhstan, is presented here. The genome is annotated for elucidation of the genomic and phenotypic diversity of thermophilic alkane-oxidizing bacteria. PMID:27491973

  11. Effect of thermal additions on the density and distribution of thermophilic amoebae and pathogenic Naegleria fowleri in a newly created cooling lake

    Energy Technology Data Exchange (ETDEWEB)

    Tyndall, R.L.; Ironside, K.S.; Metler, P.L.; Tan, E.L. (Univ. of Tennessee, Knoxville (USA)); Hazen, T.C.; Fliermans, C.B. (E.I. du Pont de Nemours and Co., Inc., Aiken, SC (USA))

    1989-03-01

    Pathogenic Naegleria fowleri is the causative agent of fatal human amoebic meningoencephalitis. The protozoan is ubiquitous in nature, and its presence is enhanced by thermal additions. In this investigation, water and sediments from a newly created cooling lake were quantitatively analyzed for the presence of thermophilic amoebae, thermophilic Naegleria spp., and the pathogen Naegleria fowleri. During periods of thermal additions, the concentrations of thermophilic amoebae and thermophilic Naegleria spp. increased as much as 5 orders of magnitude, and the concentration of the pathogen N. fowleri increased as much as 2 orders of magnitude. Concentrations of amoebae returned to prior thermal perturbation levels within 30 to 60 days after cessation of thermal additions. Increases in the thermophilic amoeba concentrations were noted in Savannah River oxbows downriver from the Savannah River plant discharge streams as compared with oxbows upriver from the discharges. Concentrations of thermophilic amoebae and thermophilic Naegleria spp. correlated significantly with temperature and conductivity. Air samples taken proximal to the lade during periods of thermal addition showed no evidence of thermophilic Naegleria spp. Isoenzyme patterns of the N. fowleri isolated from the cooling lake were identical to patterns of N. fowleri isolated from other sites in the United States and Belgium.

  12. Cooperative role of electrical stimulation on microbial metabolism and selection of thermophilic communities for p-fluoronitrobenzene treatment.

    Science.gov (United States)

    Zhang, Xueqin; Shen, Dongsheng; Feng, Huajun; Wang, Yanfeng; Li, Na; Han, Jingyi; Long, Yuyang

    2015-01-01

    A novel thermophilic bioelectrochemical system (TBES) based on electrical stimulation was established for the enhanced treatment of p-fluoronitrobenzene (p-FNB) wastewater. p-FNB removal rate constant in the TBES was 78.6% higher than that of the mesophilic BES (MBES), the elevation of which owing to high-temperature overtook the rate improvement of 50.8% in the electrocatalytic system (ECS). Additionally, an overwhelming mineralization efficiency of 91.96% ± 5.70% was obtained in the TBES. The superiority of TBES was attributed to the integrated role of electrical stimulation and high-temperature. Electrical stimulation provided an alternative for the microbial growth independent energy requirements, compensating insufficient energy support from p-FNB metabolism under the high-temperature stress. Besides, electrical stimulation facilitated microbial community evolution to form specific thermophilic biocatalysis. The uniquely selected thermophilic microorganisms including Coprothermobacter sp. and other ones cooperated to enhance p-FNB mineralization.

  13. Study on the production of enzymes from thermophiles%嗜热菌产酶现状的研究

    Institute of Scientific and Technical Information of China (English)

    潘丽贞; 陆利霞; 熊晓辉

    2012-01-01

    嗜热菌是应用最广泛的一种极端微生物,而其产生的酶在工业催化中有着广泛的应用。阐述了嗜热菌产脂肪酶、脱卤酶以及葡糖醛酸酯酶等几种酶的研究现状。%Thermophiles are a kind of extremophiles which are most widely used,and the enzymes produced by thermophiles are also widely used in industrial catalysis.The recent studies on the production of enzymes from thermophiles,such as lipase,dehalogenase,glucuronoyl esterase etc were summarized.

  14. Characteristic features in the structure and collagen-binding ability of a thermophilic collagenolytic protease from the thermophile Geobacillus collagenovorans MO-1.

    Science.gov (United States)

    Itoi, Yuichi; Horinaka, Mano; Tsujimoto, Yoshiyuki; Matsui, Hiroshi; Watanabe, Kunihiko

    2006-09-01

    A collagen-degrading thermophile, Geobacillus collagenovorans MO-1, extracellularly produces a collagenolytic protease with a large molecular mass. Complete nucleotide sequencing of this gene after gene cloning revealed that the collagenolytic protease is a member of the subtilisin family of serine proteases and consists of a signal sequence for secretion, a prosequence for maturation, a catalytic region, 14 direct repeats of 20 amino acids at the C terminus, and a region with unknown function intervening between the catalytic region and the numerous repeats. Since the unusual repeats are most likely to be cleaved in the secreted form of the enzyme, the intervening region was investigated to determine whether it participates in collagen binding to facilitate collagen degradation. It was found that the mature collagenolytic protease containing the intervening region at the C terminus bound collagen but not the other insoluble proteins, elastin and keratin. Furthermore, the intervening region fused with glutathione S-transferase showed a collagen-binding ability comparable to that of the mature collagenolytic protease. The collagen-binding ability was finally attributed to two-thirds of the intervening region which is rich in beta-strands and is approximately 35 kDa in molecular mass. In the collagenolytic protease from strain MO-1, hydrogen bonds most likely predominate over the hydrophobic interaction for collagen binding, since a higher concentration of NaCl released collagen from the enzyme surface but a nonionic detergent could not. To the best of our knowledge, this is the first report of a thermophilic collagenolytic protease containing the collagen-binding segment.

  15. Highly thermostable xylanase production from a thermophilic Geobacillus sp. strain WSUCF1 utilizing lignocellulosic biomass

    Directory of Open Access Journals (Sweden)

    Aditya eBhalla

    2015-06-01

    Full Text Available AbstractEfficient enzymatic hydrolysis of lignocellulose to fermentable sugars requires a complete repertoire of biomass deconstruction enzymes. Hemicellulases play an important role in hydrolyzing hemicellulose component of lignocellulose to xylo-oligosaccharides and xylose. Thermostable xylanases have been a focus of attention as industrially important enzymes due to their long shelf life at high temperatures. Geobacillus sp. strain WSUCF1 produced thermostable xylanase activity (crude xylanase cocktail when grown on xylan or various inexpensive untreated and pretreated lignocellulosic biomasses such as prairie cord grass and corn stover. The optimum pH and temperature for the crude xylanase cocktail were 6.5 and 70ºC, respectively. The WSUCF1 crude xylanase was found to be highly thermostable with half-lives of 18 and 12 days at 60 and 70ºC, respectively. At 70ºC, rates of xylan hydrolysis were also found to be better with the WSUCF1 secretome than those with commercial enzymes, i.e., for WSUCF1 crude xylanase, CellicHTec2, and AccelleraseXY, the percent xylan conversions were 68.9, 49.4, and 28.92, respectively. To the best of our knowledge, WSUCF1 crude xylanase cocktail is among the most thermostable xylanases produced by thermophilic Geobacillus spp. and other thermophilic microbes (optimum growth temperature ≤70ºC. High thermostability, activity over wide range of temperatures, and better xylan hydrolysis than commercial enzymes make WSUCF1 crude xylanase suitable for thermophilic lignocellulose bioconversion processes.

  16. High yield simultaneous hydrogen and ethanol production under extreme-thermophilic (70 C) mixed culture environment

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chenxi [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); Department of Environmental Engineering, Technical University of Denmark, DK-2800, Kgs Lyngby (Denmark); O-Thong, Sompong [Department of Biology, Faculty of Science, Thaksin University, Patthalung 93110 (Thailand); Karakashev, Dimitar; Angelidaki, Irini [Department of Environmental Engineering, Technical University of Denmark, DK-2800, Kgs Lyngby (Denmark); Lu, Wenjing; Wang, Hongtao [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2009-07-15

    The effect of pH and medium composition on extreme-thermophilic (70 C) dark fermentative simultaneous hydrogen and ethanol production (process performance and microbial ecology) was investigated. Hydrogen and ethanol yields were optimized with respect to glucose, peptone, FeSO{sub 4}, NaHCO{sub 3}, yeast extract, trace mineral salts, vitamins, and phosphate buffer concentrations as well as initial pH as independent variables. A combination of low levels of both glucose ({<=}2 g/L) and vitamin solutions ({<=}1 mL/L) and high levels of initial pH ({>=}7), mineral salts solution ({>=}5 mL/L) and FeSO{sub 4} ({>=}100 mg/L) stimulated the hydrogen production, while high level of glucose ({>=}5 g/L) and low levels of both initial pH ({<=}5.5) and mineral salts solution ({<=}1 mL/L) enhanced the ethanol production. High yield of simultaneous hydrogen and ethanol production (1.58 mol H{sub 2}/mol glucose combined with an ethanol yield of 0.90 mol ethanol/mol glucose) was achieved under extreme-thermophilic mixed culture environment. Results obtained showed that the shift of the metabolic pathways favouring either hydrogen or ethanol production was affected by the change in cultivation conditions (pH and medium composition). The mixed culture in this study demonstrated flexible ability for simultaneous hydrogen and ethanol production, depending on pH and nutrients formulation. The microorganisms involved could be regarded as simultaneous hydrogen/ethanol producers, as hydrogen and ethanol fermentation under all conditions was carried out by a group of extreme-thermophilic bacterial species related to Thermoanaerobacter, Thermoanaerobacterium and Caldanaerobacter. (author)

  17. Conversion of hemicelluloses and D-xylose into ethanol by the use of thermophilic anaerobic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    Ethanol is a CO{sub 2} neutral liquid fuel that can substitute the use of fossil fuels in the transportation sector, thereby reducing the CO{sub 2} emission to the atmosphere. CO{sub 2} emission is suspected to contribute significantly to the so-called greenhouse effect, the global heating. Substrates for production of ethanol must be cheap and plentiful. This can be met by the use of lignocellulosic biomass such as willow, wheat straw, hardwood and softwood. However, the complexity of these polymeric substrates and the presence of several types of carbohydrates (glucose, xylose, mannose, galactose, arabinose) require additional treatment to release the useful carbohydrates and ferment the major carbohydrates fractions. The costs related to the ethanol-production must be kept at a minimum to be price competitive compared to gasoline. Therefore all of the carbohydrates present in lignocellulose need to be converted into ethanol. Glucose can be fermented to ethanol by yeast strains such as Saccharomyces cerevisiae, which, however, is unable to ferment the other major carbohydrate fraction, D-xylose. Thermophilic anaerobic ethanol producing bacteria can be used for fermentation of the hemicelluloses fraction of lignocellulosic biomass. However, physiological studies of thermophilic anaerobic bacteria have shown that the ethanol yield decreases at increasing substrate concentration. The biochemical limitations causing this phenomenon are not known in detail. Physiological and biochemical studies of a newly characterized thermophilic anaerobic ethanol producing bacterium, Thermoanaerobacter mathranii, was performed. This study included extraction of intracellular metabolites and enzymes of the pentose phosphate pathway and glycolysis. These studies revealed several bottlenecks in the D-xylose metabolism. This knowledge makes way for physiological and genetic engineering of this strain to improve the ethanol yield and productivity at high concentration of D-xylose. (au)

  18. Effective Thermophilic Composting of Crop Residues for Inactivation of Tobacco Mosaic Virus

    Directory of Open Access Journals (Sweden)

    Abdel E. Ghaly

    2006-01-01

    Full Text Available An effective thermophilic composting bioreactor, in which a homogenous distribution of temperature was maintained at 63-65°C by the addition of a bioavailable carbon and low mixing, was developed. The bioreactor operated on a mixture of tomato plant residues-wood shavings-municipal solid waste compost infected with tobacco mosaic virus (TMV. The initial C: N ratio and moisture content of the compost mixture were adjusted to 30:1 and 60%, respectively. The composting process was successful in destroying the tobacco mosaic virus. The results showed that the ability of the untreated virus (inoculum to infect tobacco plants (150 LL L-1 was much higher than its ability to infect tomato plants (22 LL L-1. The TMV completely lost its ability to infect the leaves of susceptible hosts (tobacco and tomato plants after 96 hrs of controlled thermophilic (63-65°C composting (or 126 h from the start of the composting process. Semilog plots of the ratio of the infection ability of the surviving virus to that of the initial inoculum (as measured by the number of local lesions were developed. The decimal reduction time (the time necessary to reduce the infection ability of TMV by 1-log or 90% was found to be 62.4 and 109.7 hrs for tobacco and tomato plants, respectively. The relatively short time required for complete inactivation of TMV in this study was achieved as a result of the extension of the thermophilic stage and maintaining a constant high temperature with a uniform temperature distribution by the continuous addition of the proper amount of bioavailable carbon (used cooking oil and low mixing.

  19. Mechanisms for stabilisation and the maintenance of solubility in proteins from thermophiles

    Directory of Open Access Journals (Sweden)

    Warwicker Jim

    2007-03-01

    Full Text Available Abstract Background The database of protein structures contains representatives from organisms with a range of growth temperatures. Various properties have been studied in a search for the molecular basis of protein adaptation to higher growth temperature. Charged groups have emerged as key distinguishing factors for proteins from thermophiles and mesophiles. Results A dataset of 291 thermophile-derived protein structures is compared with mesophile proteins. Calculations of electrostatic interactions support the importance of charges, but indicate that increases in charge contribution to folded state stabilisation do not generally correlate with the numbers of charged groups. Relative propensities of charged groups vary, such as the substitution of glutamic for aspartic acid sidechains. Calculations suggest an energetic basis, with less dehydration for longer sidechains. Most other properties studied show weak or insignificant separation of proteins from moderate thermophiles or hyperthermophiles and mesophiles, including an estimate of the difference in sidechain rotameric entropy upon protein folding. An exception is increased burial of alanine and proline residues and decreased burial of phenylalanine, methionine, tyrosine and tryptophan in hyperthermophile proteins compared to those from mesophiles. Conclusion Since an increase in the number of charged groups for hyperthermophile proteins is separable from charged group contribution to folded state stability, we hypothesise that charged group propensity is important in the context of protein solubility and the prevention of aggregation. Accordingly we find some separation between mesophile and hyperthermophile proteins when looking at the largest surface patch that does not contain a charged sidechain. With regard to our observation that aromatic sidechains are less buried in hyperthermophile proteins, further analysis indicates that the placement of some of these groups may facilitate the

  20. Methane Emission from Digestion of Palm Oil Mill Effluent (POME in a Thermophilic Anaerobic Reactor

    Directory of Open Access Journals (Sweden)

    I Irvan

    2012-04-01

    Full Text Available As the issue of global warming draws increasing concern, many studies to reduce CO2 and CH4 gases (greenhouse gases, GHG have been implemented in several countries, including in Indonesia. Considering that Indonesia has a huge numbers of palm oil mills, no doubt if their waste water treatment as one of the major sources in GHG.  This paper presents the results from a research project between Metawater Co., Ltd.-Japan and University of Sumatera Utara-Indonesia. The objective of the research is to study the methane emission of thermophilic fermentation in the treatment of palm oil mill effluent (POME on a laboratory scale. Anaerobic digestion was performed in two-litre water jacketed biodigester type continuous stirred tank reactor (CSTR and operated at a thermophilic temperature (55 oC. As raw material, a real liquid waste (POME from palm oil mill was used. Fresh POME was obtained from seeding pond of PTPN II waste water treatment facility which has concentration of 39.7 g of VS/L and COD value of 59,000 mg/L. To gain precise results, complete recording and reliable equipment of reactor was employed. As the experimental results, for hydraulic retention time (HRT 8 days, VS decomposition rate of 63.5% and gas generation of 6.05-9.82 L/day were obtained, while for HRT 6 and 4 days, VS decomposition rate of 61.2, 53.3% and gas generation of  6.93-8.94  and  13.95-16.14 L/day were obtained respectively. Keywords—methane (CH4, palm oil mill effluent (POME, anaerobic digestion, thermophilic, green house gases (GHG

  1. Long-term forest dynamics at Gribskov, eastern Denmark with early-Holocene evidence for thermophilous broadleaved tree species

    DEFF Research Database (Denmark)

    Overballe-Petersen, Mette V; Nielsen, Anne Birgitte; Hannon, Gina E.;

    2012-01-01

    thermophilous broadleaved trees, including Quercus sp., Tilia sp. and Ulmus sp. The macrofossils contribute to the vegetation reconstruction with evidence for local presence of species with low pollen productivity or easily degraded pollen types such as Populus. The charcoal record shows frequent burning during...... no clear indication of post-depositional disturbance, although a possible short-lived hiatus occurs around 6500 cal. BP. The early pollen record from thermophilous trees could indicate that there may have been some downwash following sediment desiccation through wood peat layers deposited between c. 6500...

  2. Removal of Sulfur Compounds from Coal by the Thermophilic Organism Sulfolobus acidocaldarius

    OpenAIRE

    KARGI, Fikret; Robinson, James M.

    1982-01-01

    The thermophilic, reduced-sulfur, iron-oxidizing bacterium Sulfolobus acidocaldarius was used for the removal of sulfur compounds from coal. The inclusion of complex nutrients such as yeast extract and peptone, and chemical oxidizing agents, 0.01 M FeCl3 into leaching medium, reduced the rate and the extent of sulfur removal from coal. The rate of sulfur removal by S. acidocaldarius was strongly dependent on the sulfur content of the coal and on the total external surface area of coal particl...

  3. Geobacillus icigianus sp. nov., a thermophilic bacterium isolated from a hot spring.

    Science.gov (United States)

    Bryanskaya, Alla V; Rozanov, Alexey S; Slynko, Nikolay M; Shekhovtsov, Sergey V; Peltek, Sergey E

    2015-03-01

    A Gram-reaction-positive, motile, thermophilic spore-forming strain, G1w1(T), was isolated from a hot spring of the Valley of Geysers, Kamchatka (Russia). Based on data from the present polyphasic taxonomic study, including phylogenetic analysis of 16S rRNA and spo0A gene sequences, the strain is considered to represent a novel species of the genus Geobacillus, for which the name Geobacillus icigianus sp. nov. is proposed. The type strain is G1w1(T) ( = VKM B-2853(T) = DSM 28325(T)).

  4. Thermophilic fermentation of acetoin and 2,3-butanediol by a novel Geobacillus strain

    Directory of Open Access Journals (Sweden)

    Xiao Zijun

    2012-12-01

    Full Text Available Abstract Background Acetoin and 2,3-butanediol are two important biorefinery platform chemicals. They are currently fermented below 40°C using mesophilic strains, but the processes often suffer from bacterial contamination. Results This work reports the isolation and identification of a novel aerobic Geobacillus strain XT15 capable of producing both of these chemicals under elevated temperatures, thus reducing the risk of bacterial contamination. The optimum growth temperature was found to be between 45 and 55°C and the medium initial pH to be 8.0. In addition to glucose, galactose, mannitol, arabionose, and xylose were all acceptable substrates, enabling the potential use of cellulosic biomass as the feedstock. XT15 preferred organic nitrogen sources including corn steep liquor powder, a cheap by-product from corn wet-milling. At 55°C, 7.7 g/L of acetoin and 14.5 g/L of 2,3-butanediol could be obtained using corn steep liquor powder as a nitrogen source. Thirteen volatile products from the cultivation broth of XT15 were identified by gas chromatography–mass spectrometry. Acetoin, 2,3-butanediol, and their derivatives including a novel metabolite 2,3-dihydroxy-3-methylheptan-4-one, accounted for a total of about 96% of all the volatile products. In contrast, organic acids and other products were minor by-products. α-Acetolactate decarboxylase and acetoin:2,6-dichlorophenolindophenol oxidoreductase in XT15, the two key enzymes in acetoin metabolic pathway, were found to be both moderately thermophilic with the identical optimum temperature of 45°C. Conclusions Geobacillus sp. XT15 is the first naturally occurring thermophile excreting acetoin and/or 2,3-butanediol. This work has demonstrated the attractive prospect of developing it as an industrial strain in the thermophilic fermentation of acetoin and 2,3-butanediol with improved anti-contamination performance. The novel metabolites and enzymes identified in XT15 also indicated its

  5. Mass and Energy Balances of Dry Thermophilic Anaerobic Digestion Treating Swine Manure Mixed with Rice Straw

    OpenAIRE

    Sheng Zhou; Jining Zhang; Guoyan Zou; Shohei Riya; Masaaki Hosomi

    2015-01-01

    To evaluate the feasibility of swine manure treatment by a proposed Dry Thermophilic Anaerobic Digestion (DT-AD) system, we evaluated the methane yield of swine manure treated using a DT-AD method with rice straw under different C/N ratios and solid retention time (SRT) and calculated the mass and energy balances when the DT-AD system is used for swine manure treatment from a model farm with 1000 pigs and the digested residue is used for forage rice production. A traditional swine manure trea...

  6. Complete genome sequence of thermophilic Bacillus smithii type strain DSM 4216T

    DEFF Research Database (Denmark)

    Bosma, Elleke Fenna; Koehorst, Jasper J.; van Hijum, Sacha A. F. T.;

    2016-01-01

    Bacillus smithii is a facultatively anaerobic, thermophilic bacterium able to use a variety of sugars that can be derived from lignocellulosic feedstocks. Being genetically accessible, it is a potential new host for biotechnological production of green chemicals from renewable resources. We...... determined the complete genomic sequence of the B. smithii type strain DSM 4216T, which consists of a 3,368,778 bp chromosome (GenBank accession number CP012024.1) and a 12,514 bp plasmid (GenBank accession number CP012025.1), together encoding 3880 genes. Genome annotation via RAST was complemented...

  7. Production and Purification of Extracellular D-Xylose Isomerase from an Alkaliphilic, Thermophilic Bacillus sp. †

    OpenAIRE

    Chauthaiwale, Jyoti; Rao, Mala

    1994-01-01

    An alkaliphilic, thermophilic Bacillus sp. (NCIM 59) produced extracellular xylose isomerase at pH 10 and 50°C by using xylose or wheat bran as the carbon source. The distribution of xylose isomerase as a function of growth in comparison with distributions of extra- and intracellular marker enzymes such as xylanase and β-galactosidase revealed that xylose isomerase was truly secreted as an extracellular enzyme and was not released because of sporulation or lysis. The enzyme was purified to ho...

  8. Effect of xylose and nutrients concentration on ethanol production by a newly isolated extreme thermophilic bacterium

    DEFF Research Database (Denmark)

    Tomás, Ana Faria; Karakashev, Dimitar Borisov; Angelidaki, Irini

    2011-01-01

    An extreme thermophilic ethanol-producing strain was isolated from an ethanol high-yielding mixed culture, originally isolated from a hydrogen producing reactor operated at 70 °C. Ethanol yields were assessed with increasing concentrations of xylose, up to 20 g/l. The ability of the strain to gro...... product under most of the conditions tested, including in media lacking vitamins, peptone and yeast extract. The results indicate that this new organism is a promising candidate for the development of a second generation bio-ethanol production process. © IWA Publishing 2011....

  9. Modulation of Nucleotide Specificity of Thermophilic FoF1-ATP Synthase by ϵ-Subunit

    OpenAIRE

    Suzuki, Toshiharu; Wakabayashi, Chiaki; TANAKA, Kazumi; Feniouk, Boris A.; Yoshida, Masasuke

    2011-01-01

    The C-terminal two α-helices of the ϵ-subunit of thermophilic Bacillus FoF1-ATP synthase (TFoF1) adopt two conformations: an extended long arm (“up-state”) and a retracted hairpin (“down-state”). As ATP becomes poor, ϵ changes the conformation from the down-state to the up-state and suppresses further ATP hydrolysis. Using TFoF1 expressed in Escherichia coli, we compared TFoF1 with up- and down-state ϵ in the NTP (ATP, GTP, UTP, and CTP) synthesis reactions. TFoF1 with the up-state ϵ was achi...

  10. Comparative study on the selective chalcopyrite bioleaching of a molybdenite concentrate with mesophilic and thermophilic bacteria.

    Science.gov (United States)

    Romano, P; Blázquez, M L; Alguacil, F J; Muñoz, J A; Ballester, A; González, F

    2001-03-01

    This study evaluates different bioleaching treatments of a molybdenite concentrate using mesophilic and thermophilic bacterial cultures. Further studies on the chemical leaching and the electrochemical behavior of the MoS(2) concentrate were carried out. Bioleaching tests showed a progressive removal of chalcopyrite from the molybdenite concentrate with an increase in temperature. Chemical leaching tests support the idea of an indirect attack of the concentrate. Electrochemical tests indicate that chalcopyrite dissolution is favored when molybdenite is present. Therefore, this type of bioleaching treatment could be applied to purify molybdenite flotation concentrates by selectively dissolving chalcopyrite. PMID:11257551

  11. A moderately thermophilic ammonia-oxidizing crenarchaeote from a hot spring

    OpenAIRE

    Hatzenpichler, Roland; Elena V Lebedeva; Spieck, Eva; Stoecker, Kilian; Richter, Andreas; Daims, Holger; WAGNER, Michael

    2008-01-01

    The recent discovery of ammonia-oxidizing archaea (AOA) dramatically changed our perception of the diversity and evolutionary history of microbes involved in nitrification. In this study, a moderately thermophilic (46°C) ammonia-oxidizing enrichment culture, which had been seeded with biomass from a hot spring, was screened for ammonia oxidizers. Although gene sequences for crenarchaeotal 16S rRNA and two subunits of the ammonia monooxygenase (amoA and amoB) were detected via PCR, no hints fo...

  12. Biohydrogen production from xylose at extreme thermophilic temperatures (70 degrees C) by mixed culture fermentation

    DEFF Research Database (Denmark)

    Kongjan, Prawit; Min, Booki; Angelidaki, Irini

    2009-01-01

    Biohydrogen production from xylose at extreme thermophilic temperatures (70 degrees C) was investigated in batch and continuous-mode operation. Biohydrogen was successfully produced from xylose by repeated batch cultivations with mixed culture received from a biohydrogen reactor treating household...... high hydrogen partial pressure (>0.14 atm) was present in the headspace of the batch reactors. Biohydrogen could be successfully produced in continuously stirred reactor (CSTR) operated at 72-h hydraulic retention time (HRT) with 1 g/L of xylose as substrate at 70 degrees C. The hydrogen production...

  13. Immobilization of cells with nitrilase activity from a thermophilic bacterial strain.

    Science.gov (United States)

    Kabaivanova, L; Dobreva, E; Dimitrov, P; Emanuilova, E

    2005-01-01

    Cells of the moderately thermophilic Bacillus sp. UG-5B strain, producing nitrilase (EC3.5.5.1), which converts nitriles directly to the corresponding acid and ammonia, were immobilized using different types of matrices and techniques. A variety of sol-gel silica hybrids were tested for entrapment and adsorption of bacterial cells as well as chemical binding on polysulphone membranes. Activation of the matrix surface with formaldehyde led to an increase in immobilization efficiency and operational stability of the biocatalysts. Among the supports screened, membranes gave the best results for enzyme activity and especially operational stability, with retention of 100% activity after eight reaction cycles.

  14. Macroscopic mass and energy balance of a pilot plant anaerobic bioreactor operated under thermophilic conditions.

    Science.gov (United States)

    Espinosa-Solares, Teodoro; Bombardiere, John; Chatfield, Mark; Domaschko, Max; Easter, Michael; Stafford, David A; Castillo-Angeles, Saul; Castellanos-Hernandez, Nehemias

    2006-01-01

    Intensive poultry production generates over 100,000 t of litter annually in West Virginia and 9 x 10(6) t nationwide. Current available technological alternatives based on thermophilic anaerobic digestion for residuals treatment are diverse. A modification of the typical continuous stirred tank reactor is a promising process being relatively stable and owing to its capability to manage considerable amounts of residuals at low operational cost. A 40-m3 pilot plant digester was used for performance evaluation considering energy input and methane production. Results suggest some changes to the pilot plant configuration are necessary to reduce power consumption although maximizing biodigester performance.

  15. Treatment efficiency and VFA composition of a thermophilic anaerobic contact reactor treating food industry wastewater

    International Nuclear Information System (INIS)

    The objective of this study was to examine the effects of organic loading rate and hydraulic retention time on volatile fatty acid composition and treatment efficiency of high rate thermophilic anaerobic contact reactor (TACR) treating potato-chips wastewaters. The operational performance of TACR was monitored from start-up by assessing chemical oxygen demand (COD) removal efficiencies, volatile fatty acid (VFA) production and biogas composition. The reactor was studied at different organic loading rates (OLRs) ranging from 0.6 to 8 kg COD/m3 d. The COD removal efficiencies were found to be 86-97% and the methane percentage of the biogas produced was 68-89% during the OLRs studied. The approximate methane yield was found to be 0.42 m3 CH4/kg CODremoved. The major intermediate products of anaerobic digestion were acetate, propionate, iso-butyrate, butyrate, iso-valerate, valerate, iso-caproate and caproate. The use of thermophilic anaerobic contact reactor offers a sustainable technology for the treatment of potato-chips wastewaters since high COD removal efficiencies and high methane percentage in the biogas produced can be attained even at high OLRs.

  16. Biotransformation of eugenol via protocatechuic acid by thermophilic Geobacillus sp. AY 946034 strain.

    Science.gov (United States)

    Giedraityte, Gražina; Kalėdienė, Lilija

    2014-04-01

    The metabolic pathway of eugenol degradation by thermophilic Geobacillus sp. AY 946034 strain was analyzed based on the lack of data about eugenol degradation by thermophiles. TLC, GC-MS, and biotransformation with resting cells showed that eugenol was oxidized through coniferyl alcohol, and ferulic and vanillic acids to protocatechuic acid before the aromatic ring was cleaved. The cell-free extract of Geobacillus sp. AY 946034 strain grown on eugenol showed a high activity of eugenol hydroxylase, feruloyl-CoA synthetase, vanillate-O-demethylase, and protocatechuate 3,4-dioxygenase. The key enzyme, protocatechuate 3,4- dioxygenase, which plays a crucial role in the degradation of various aromatic compounds, was purified 135-fold to homogeneity with a 34% overall recovery from Geobacillus sp. AY 946034. The relative molecular mass of the native enzyme was about 450 ± 10 kDa and was composed of the non-identical subunits. The pH and temperature optima for enzyme activity were 8 and 60°C, respectively. The half-life of protocatechuate 3,4-dioxygenase at the optimum temperature was 50 min.

  17. Antimicrobial Protein Candidates from the Thermophilic Geobacillus sp. Strain ZGt-1: Production, Proteomics, and Bioinformatics Analysis

    Science.gov (United States)

    Alkhalili, Rawana N.; Bernfur, Katja; Dishisha, Tarek; Mamo, Gashaw; Schelin, Jenny; Canbäck, Björn; Emanuelsson, Cecilia; Hatti-Kaul, Rajni

    2016-01-01

    A thermophilic bacterial strain, Geobacillus sp. ZGt-1, isolated from Zara hot spring in Jordan, was capable of inhibiting the growth of the thermophilic G. stearothermophilus and the mesophilic Bacillus subtilis and Salmonella typhimurium on a solid cultivation medium. Antibacterial activity was not observed when ZGt-1 was cultivated in a liquid medium; however, immobilization of the cells in agar beads that were subjected to sequential batch cultivation in the liquid medium at 60 °C showed increasing antibacterial activity up to 14 cycles. The antibacterial activity was lost on protease treatment of the culture supernatant. Concentration of the protein fraction by ammonium sulphate precipitation followed by denaturing polyacrylamide gel electrophoresis separation and analysis of the gel for antibacterial activity against G. stearothermophilus showed a distinct inhibition zone in 15–20 kDa range, suggesting that the active molecule(s) are resistant to denaturation by SDS. Mass spectrometric analysis of the protein bands around the active region resulted in identification of 22 proteins with molecular weight in the range of interest, three of which were new and are here proposed as potential antimicrobial protein candidates by in silico analysis of their amino acid sequences. Mass spectrometric analysis also indicated the presence of partial sequences of antimicrobial enzymes, amidase and dd-carboxypeptidase. PMID:27548162

  18. Modelling of the acid base properties of two thermophilic bacteria at different growth times

    Science.gov (United States)

    Heinrich, Hannah T. M.; Bremer, Phil J.; McQuillan, A. James; Daughney, Christopher J.

    2008-09-01

    Acid-base titrations and electrophoretic mobility measurements were conducted on the thermophilic bacteria Anoxybacillus flavithermus and Geobacillus stearothermophilus at two different growth times corresponding to exponential and stationary/death phase. The data showed significant differences between the two investigated growth times for both bacterial species. In stationary/death phase samples, cells were disrupted and their buffering capacity was lower than that of exponential phase cells. For G. stearothermophilus the electrophoretic mobility profiles changed dramatically. Chemical equilibrium models were developed to simultaneously describe the data from the titrations and the electrophoretic mobility measurements. A simple approach was developed to determine confidence intervals for the overall variance between the model and the experimental data, in order to identify statistically significant changes in model fit and thereby select the simplest model that was able to adequately describe each data set. Exponential phase cells of the investigated thermophiles had a higher total site concentration than the average found for mesophilic bacteria (based on a previously published generalised model for the acid-base behaviour of mesophiles), whereas the opposite was true for cells in stationary/death phase. The results of this study indicate that growth phase is an important parameter that can affect ion binding by bacteria, that growth phase should be considered when developing or employing chemical models for bacteria-bearing systems.

  19. Antimicrobial Protein Candidates from the Thermophilic Geobacillus sp. Strain ZGt-1: Production, Proteomics, and Bioinformatics Analysis

    Directory of Open Access Journals (Sweden)

    Rawana N. Alkhalili

    2016-08-01

    Full Text Available A thermophilic bacterial strain, Geobacillus sp. ZGt-1, isolated from Zara hot spring in Jordan, was capable of inhibiting the growth of the thermophilic G. stearothermophilus and the mesophilic Bacillus subtilis and Salmonella typhimurium on a solid cultivation medium. Antibacterial activity was not observed when ZGt-1 was cultivated in a liquid medium; however, immobilization of the cells in agar beads that were subjected to sequential batch cultivation in the liquid medium at 60 °C showed increasing antibacterial activity up to 14 cycles. The antibacterial activity was lost on protease treatment of the culture supernatant. Concentration of the protein fraction by ammonium sulphate precipitation followed by denaturing polyacrylamide gel electrophoresis separation and analysis of the gel for antibacterial activity against G. stearothermophilus showed a distinct inhibition zone in 15–20 kDa range, suggesting that the active molecule(s are resistant to denaturation by SDS. Mass spectrometric analysis of the protein bands around the active region resulted in identification of 22 proteins with molecular weight in the range of interest, three of which were new and are here proposed as potential antimicrobial protein candidates by in silico analysis of their amino acid sequences. Mass spectrometric analysis also indicated the presence of partial sequences of antimicrobial enzymes, amidase and dd-carboxypeptidase.

  20. Morphological and phylogenetic diversity of thermophilic cyanobacteria in Algerian hot springs.

    Science.gov (United States)

    Amarouche-Yala, Samia; Benouadah, Ali; El Ouahab Bentabet, Abd; López-García, Purificación

    2014-11-01

    Geothermal springs in Algeria have been known since the Roman Empire. They mainly locate in Eastern Algeria and are inhabited by thermophilic organisms, which include cyanobacteria forming mats and concretions. In this work, we have investigated the cyanobacterial diversity of these springs. Cyanobacteria were collected from water, concretions and mats in nine hot springs with water temperatures ranging from 39 to 93 °C. Samples were collected for isolation in culture, microscopic morphological examination, and molecular diversity analysis based on 16S rRNA gene sequences. Nineteen different cyanobacterial morphotypes were identified, the most abundant of which were three species of Leptolyngbya, accompanied by members of the genera Gloeocapsa, Gloeocapsopsis, Stigonema, Fischerella, Synechocystis, Microcoleus, Cyanobacterium, Chroococcus and Geitlerinema. Molecular diversity analyses were in good general agreement with classical identification and allowed the detection of additional species in three springs with temperatures higher than 50 °C. They corresponded to a Synechococcus clade and to relatives of the intracellularly calcifying Candidatus Gloeomargarita lithophora. The hottest springs were dominated by members of Leptolyngbya, Synechococcus-like cyanobacteria and Gloeomargarita, whereas Oscillatoriales other than Leptolyngbya, Chroococcales and Stigonematales dominated lower temperature springs. The isolation of some of these strains sets the ground for future studies on the biology of thermophilic cyanobacteria.

  1. Boosting dark fermentation with co-cultures of extreme thermophiles for biohythane production from garden waste.

    Science.gov (United States)

    Abreu, Angela A; Tavares, Fábio; Alves, Maria Madalena; Pereira, Maria Alcina

    2016-11-01

    Proof of principle of biohythane and potential energy production from garden waste (GW) is demonstrated in this study in a two-step process coupling dark fermentation and anaerobic digestion. The synergistic effect of using co-cultures of extreme thermophiles to intensify biohydrogen dark fermentation is demonstrated using xylose, cellobiose and GW. Co-culture of Caldicellulosiruptor saccharolyticus and Thermotoga maritima showed higher hydrogen production yields from xylose (2.7±0.1molmol(-1) total sugar) and cellobiose (4.8±0.3molmol(-1) total sugar) compared to individual cultures. Co-culture of extreme thermophiles C. saccharolyticus and Caldicellulosiruptor bescii increased synergistically the hydrogen production yield from GW (98.3±6.9Lkg(-1) (VS)) compared to individual cultures and co-culture of T. maritima and C. saccharolyticus. The biochemical methane potential of the fermentation end-products was 322±10Lkg(-1) (CODt). Biohythane, a biogas enriched with 15% hydrogen could be obtained from GW, yielding a potential energy generation of 22.2MJkg(-1) (VS). PMID:27484669

  2. Bioleaching of electronic scrap by mixed culture of moderately thermophilic microorganisms

    Science.gov (United States)

    Ivǎnuş, D.; ǎnuş, R. C., IV; Cǎlmuc, F.

    2010-06-01

    A process for the metal recovery from electronic scrap using bacterial leaching was investigated. A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages (AMDs) samples collected from several sulphide mines in Romania, and the bioleaching of electronic scrap was conducted both in shake flask and bioreactor. The results show that in the shake flask, the mixture can tolerate 50 g/L scrap after being acclimated to gradually increased concentrations of scrap. The copper extraction increases obviously in bioleaching of scrap with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min, 74% copper can be extracted in the pulp of 50 g/L scrap after 20 d. Compared with copper extractions of mesophilic culture, unacclimated culture and acclimated culture without addition of yeast extract, that of accliniated culture with addition of yeast extract is increased by 53%, 44% and 16%, respectively. In a completely stirred tank reactor, the mass fraction of copper and total iron extraction reach up to 81% and 56%, respectively. The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from electronic scrap effectively.

  3. [Effects of Thermophilic Composting on Antibiotic Resistance Genes (ARGs) of Swine Manure Source].

    Science.gov (United States)

    Zheng, Ning-guo; Huang, Nan; Wang, Wei-wei; Yu, Man; Chen, Xiao-yang; Yao, Yan-lai; Wang, Wei-ping; Hong, Chun-lai

    2016-05-15

    To investigate the effects of thermophilic composting process on antibiotic resistance genes (ARGs) of swine manure source at a field scale, the abundance of four erythromycin resistance genes (ermA, ermB, ermC and ermF), three β-lactam resistance genes (blaTEM, blaCTX and blaSHV) and two quinolone resistance genes (qnrA and qnrS) were quantified by quantitative PCR ( qPCR) during the composting process. The results suggested that the erm genes' copy numbers were significantly higher than those of the bla and qnr genes in the early stage of composting (P erm genes was ermB (9.88 x 10⁸ copies · g⁻¹), following by ermF (9.4 x 10⁸ copies · g⁻¹). At the end of the composting process, bla and qnr genes were at low levels, while erm genes were still at high levels. Even through ermF was proliferated comparing with the initial copies. These results indicated that thermophilic composting process could not effectively remove all ARGs. For some ARGs, compost may be a good bioreactor resulting in their proliferation. Application of composting products on farmland may cause transference of ARGs. PMID:27506057

  4. Performance and methanogenic community of rotating disk reactor packed with polyurethane during thermophilic anaerobic digestion

    International Nuclear Information System (INIS)

    A newly developed anaerobic rotating disk reactor (ARDR) packed with polyurethane was used in continuous mode for organic waste removal under thermophilic (55 oC) anaerobic conditions. This paper reports the effects of the rotational speed on the methanogenic performance and community in an ARDR supplied with acetic acid synthetic wastewater as the organic substrate. The best performance was obtained from the ARDR with the rotational speed (ω) of 30 rpm. The average removal of dissolved organic carbon was 98.5%, and the methane production rate was 393 ml/l-reactor/day at an organic loading rate of 2.69 g/l-reactor/day. Under these operational conditions, the reactor had a greater biomass retention capacity and better reactor performance than those at other rotational speeds (0, 5 and 60 rpm). The results of 16S rRNA phylogenetic analysis indicated that the major methanogens in the reactor belonged to the genus Methanosarcina spp. The results of real-time polymerase chain reaction (PCR) analysis suggested that the cell density of methanogenic archaea immobilized on the polyurethane foam disk could be concentrated more than 2000 times relative to those in the original thermophilic sludge. Scanning electron microphotographs showed that there were more immobilized microbes at ω of 30 rpm than 60 rpm. A rotational speed on the outer layer of the disk of 6.6 m/min could be appropriate for anaerobic digestion using the polyurethane ARDR

  5. X-ray Crystallographic Structure of Thermophilic Rhodopsin: IMPLICATIONS FOR HIGH THERMAL STABILITY AND OPTOGENETIC FUNCTION.

    Science.gov (United States)

    Tsukamoto, Takashi; Mizutani, Kenji; Hasegawa, Taisuke; Takahashi, Megumi; Honda, Naoya; Hashimoto, Naoki; Shimono, Kazumi; Yamashita, Keitaro; Yamamoto, Masaki; Miyauchi, Seiji; Takagi, Shin; Hayashi, Shigehiko; Murata, Takeshi; Sudo, Yuki

    2016-06-01

    Thermophilic rhodopsin (TR) is a photoreceptor protein with an extremely high thermal stability and the first characterized light-driven electrogenic proton pump derived from the extreme thermophile Thermus thermophilus JL-18. In this study, we confirmed its high thermal stability compared with other microbial rhodopsins and also report the potential availability of TR for optogenetics as a light-induced neural silencer. The x-ray crystal structure of TR revealed that its overall structure is quite similar to that of xanthorhodopsin, including the presence of a putative binding site for a carotenoid antenna; but several distinct structural characteristics of TR, including a decreased surface charge and a larger number of hydrophobic residues and aromatic-aromatic interactions, were also clarified. Based on the crystal structure, the structural changes of TR upon thermal stimulation were investigated by molecular dynamics simulations. The simulations revealed the presence of a thermally induced structural substate in which an increase of hydrophobic interactions in the extracellular domain, the movement of extracellular domains, the formation of a hydrogen bond, and the tilting of transmembrane helices were observed. From the computational and mutational analysis, we propose that an extracellular LPGG motif between helices F and G plays an important role in the thermal stability, acting as a "thermal sensor." These findings will be valuable for understanding retinal proteins with regard to high protein stability and high optogenetic performance. PMID:27129243

  6. Bacterial community analysis of swine manure treated with autothermal thermophilic aerobic digestion.

    Science.gov (United States)

    Han, Il; Congeevaram, Shankar; Ki, Dong-Won; Oh, Byoung-Taek; Park, Joonhong

    2011-02-01

    Due to the environmental problems associated with disposal of livestock sludge, many stabilization studies emphasizing on the sludge volume reduction were performed. However, little is known about the microbial risk present in sludge and its stabilized products. This study microbiologically explored the effects of anaerobic lagoon fermentation (ALF) and autothermal thermophilic aerobic digestion (ATAD) on pathogen-related risk of raw swine manure by using culture-independent 16S rDNA cloning and sequencing methods. In raw swine manure, clones closely related to pathogens such as Dialister pneumosintes, Erysipelothrix rhusiopathiae, Succinivibrioan dextrinosolvens, and Schineria sp. were detected. Meanwhile, in the mesophilic ALF-treated swine manure, bacterial community clones closely related to pathogens such as Schineria sp. and Succinivibrio dextrinosolvens were still detected. Interestingly, the ATAD treatment resulted in no detection of clones closely related to pathogens in the stabilized thermophilic bacterial community, with the predominance of novel Clostridia class populations. These findings support the superiority of ATAD in selectively reducing potential human and animal pathogens compared to ALF, which is a typical manure stabilization method used in livestock farms. PMID:20922382

  7. ATP as an indicator of biomass activity in thermophilic upflow anaerobic sludge blanket reactor

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This work investigated the biomass activity in a thermophilic upflow anaerobic sludge blanket (UASB) reactor of wastewater treatment. Synthetic textile wastewater with pH 10-11, COD level of 2000-3000 mg/L was tested. Cellular adenosine triphosphate (ATP) in volatile solids (VS; mg ATP/gVS) was measured and expressed as specific ATP content to compare the biomass activity in up zone and lower zone in UASB reactor. The result shows that the specific ATP content based on total volatile solids (VS)in lower zone (0. 046 mgATP/gVS average) is much lower than that in up zone (0.62 mgATP/gVS average) due to high content of inactive biomass and high pH in lower zone. The SATP in up zone increases as HRT increases and approaches to a maximum value of 0.85 mgATP/gVS at HRT of 7h, then decreases. It shows most of the total VS in up zone represent active bacterial biomass at HRT of 7h. Rate of subtract utilization is directly related to the activity of microorganisms in the reactor. The effect of HRT on SATP in lower zone is not as significant as on SATP in up zone. The buffer capacity of the thermophilic UASB reactor is very good. It is the activity of sludge granules in lower zone that give the UASB reactor such a good buffer capacity to the inlet high pH.

  8. Aerobic moving bed biofilm reactor treating thermomechanical pulping whitewater under thermophilic conditions.

    Science.gov (United States)

    Jahren, Sigrun J; Rintala, Jukka A; Odegaard, Hallvard

    2002-02-01

    The continuously operated laboratory scale Kaldnes moving bed biofilm reactor (MBBR) was used for thermophilic (55 degrees C) aerobic treatment of TMP whitewater. In the MBBR, the biomass is grown on carrier elements that move along with the water in the reactor. Inoculation with mesophilic activated sludge gave 60-65% SCOD removal from the first day onwards. During the 107 days of experiment, the 60-65% SCOD removals were achieved at organic loading rates of 2.5-3.5 kg SCODm(-3) d(-1), the highest loading rates applied during the run and HRT of 13-22h. Carbohydrates, which contributed to 50-60% of the influent SCOD. were removed by 90-95%, while less than 15% of the lignin-like material (30-35% of SCODin) was removed. The sludge yield was 0.23g VSSg SCOD(-1)removed. The results show that the aerobic biofilm process can be successfully operated under thermophilic conditions. PMID:11848344

  9. Evaluation of two-phase thermophilic anaerobic methane fermentation for the treatment of garbage

    International Nuclear Information System (INIS)

    Municipal solid wastes (MSW) in Japan are generally incinerated. However, in recent years, garbage has been recognized as a renewable energy source. This has resulted in an increase in the use of biological processes, such as anaerobic digestion, to treat organic waste such as sewage sludge and garbage. The two phases of anaerobic digestion are the acidogenic phase and the methane producing phase. Both differ significantly in their nutritional and physiological requirements. This study evaluated the effectiveness of treating garbage with the two-phase thermophilic methane fermentation system (TPS). The performance of the acid fermentation phase in TPS was examined with particular reference to operational parameters such as pH, hydraulic retention time and organic loading rate on volatile fatty acid fermentation. It was shown that TPS was more efficient than the single-phase thermophilic methane fermentation system (SPS). Acidification control in the first stage resulted in better stability of methane fermentation in the second stage. VFA formation was optimized at a pH of 6. The recovery ratios of VFAs and methane were achieved in the range of 42 to 44 per cent and 88 to 91 per cent of garbage by high organic loading rate respectively. 12 refs., 6 tabs., 4 figs

  10. Auto heated Thermophilic Aerobic Digestion of sewage sludge; Digestion aerobia termofila autosostenida de lodos urbanos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia de las Heras, J. L.; Gutierrez, I.

    2002-07-01

    Auto heated Thermophilic Aerobic Digestion (ATAD) is one of the most promising technologies for applying the digested sludge to soil amendment. The system was studied in the 60's and developed mostly in Europe since the 70's. The full-scale facilities improvement ran in parallel to the scientific and legislative worry about the presence of pathogenic organisms both in the raw and the digested sewage sludge. ATAD is usually a two stage aerobic process working in the thermophilic temperature range (40 to 80 degree centigree) without any external heat source; the heat produced by the biochemical exergonic reactions during the aerobic degradation of the organic sludge holds the desired temperature values. A comparison of this system with the existing anaerobic stabilisation processes shows as main advantages a high hygienization capacity, small reactor volume for the same organic loading, is resistant to overloading and temperature shocks, is easily manageable, and is economically feasible for small.medium size populations. This process is specially suitable to fulfill the law requirements imposed by the most demanding countries regarding the application of treated sewage sludge to soil improvement. (Author) 19 refs.

  11. [Screening and Enzyme Production Characteristics of Thermophilic Cellulase-producing Strains].

    Science.gov (United States)

    Feng, Hong-mei; Qin, Yong-sheng; Li, Xiao-fan; Zhou, Jin-xing; Peng, Xia-wei

    2016-04-15

    A total of 6 thermophilic cellulase-producing strainswere isolated from organic garden waste mixed chicken composting at thermophilic period. These isolates were identified as Streptomyces thermoviolaceus, S. thermodiastaticus, S. thermocarboxydus, S. albidoflavus, S. thermovulgaris and Brevibacillus borstelensis through 16S rRNA gene sequence alignment and phylogenetic tree analysis. The cellulose-degrading microbial community has been investigated in few researches so far both at home and abroad. In this study, the mixed strains M-1 was made up of the 6 cellulose-decomposing microorganisms. The CMCase activity of the mixed strains M- 1 was stronger than any of the 6 single strains. Production of CMCase from mixed strains M-1 was studied by optimizing different physico-chemical parameters. The Maximum CMCase production (135.9 U · mL⁻¹) of strains M-1 was achieved at 45 °C in a liquid medium (pH 4) inoculated with 1% (volume fraction), containing a mixture of wheat bran and starch, corn flour and KNO₃. After optimization of separation conditions, CMCase production capacity was improved by 1.8 times. PMID:27548981

  12. The detection of thermophilous forest hotspots in Poland using geostatistical interpolation of plant richness

    Directory of Open Access Journals (Sweden)

    Marcin Kiedrzyński

    2014-07-01

    Full Text Available Attempts to study biodiversity hotspots on a regional scale should combine compositional and functionalist criteria. The detection of hotspots in this study uses one ecologically similar group of high conservation value species as hotspot indicators, as well as focal habitat indicators, to detect the distribution of suitable environmental conditions. The method is assessed with reference to thermophilous forests in Poland – key habitats for many rare and relict species. Twenty-six high conservation priority species were used as hotspot indicators, and ten plant taxa characteristic of the Quercetalia pubescenti-petraeae phytosociological order were used as focal habitat indicators. Species distribution data was based on a 10 × 10 km grid. The number of species per grid square was interpolated by the ordinary kriging geostatistical method. Our analysis largely determined the distribution of areas with concentration of thermophilous forest flora, but also regional disjunctions and geographical barriers. Indicator species richness can be interpreted as a reflection of the actual state of habitat conditions. It can also be used to determine the location of potential species refugia and possible past and future migration routes.

  13. Role of Mn2+ and Compatible Solutes in the Radiation Resistance of Thermophilic Bacteria and Archaea

    Directory of Open Access Journals (Sweden)

    Kimberly M. Webb

    2012-01-01

    Full Text Available Radiation-resistant bacteria have garnered a great deal of attention from scientists seeking to expose the mechanisms underlying their incredible survival abilities. Recent analyses showed that the resistance to ionizing radiation (IR in the archaeon Halobacterium salinarum is dependent upon Mn-antioxidant complexes responsible for the scavenging of reactive oxygen species (ROS generated by radiation. Here we examined the role of the compatible solutes trehalose, mannosylglycerate, and di-myo-inositol phosphate in the radiation resistance of aerobic and anaerobic thermophiles. We found that the IR resistance of the thermophilic bacteria Rubrobacter xylanophilus and Rubrobacter radiotolerans was highly correlated to the accumulation of high intracellular concentration of trehalose in association with Mn, supporting the model of Mn2+-dependent ROS scavenging in the aerobes. In contrast, the hyperthermophilic archaea Thermococcus gammatolerans and Pyrococcus furiosus did not contain significant amounts of intracellular Mn, and we found no significant antioxidant activity from mannosylglycerate and di-myo-inositol phosphate in vitro. We therefore propose that the low levels of IR-generated ROS under anaerobic conditions combined with highly constitutively expressed detoxification systems in these anaerobes are key to their radiation resistance and circumvent the need for the accumulation of Mn-antioxidant complexes in the cell.

  14. Bioleaching of electronic scrap by mixed culture of moderately thermophilic microorganisms

    Directory of Open Access Journals (Sweden)

    Ivănuş D.

    2010-06-01

    Full Text Available A process for the metal recovery from electronic scrap using bacterial leaching was investigated. A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages (AMDs samples collected from several sulphide mines in Romania, and the bioleaching of electronic scrap was conducted both in shake flask and bioreactor. The results show that in the shake flask, the mixture can tolerate 50 g/L scrap after being acclimated to gradually increased concentrations of scrap. The copper extraction increases obviously in bioleaching of scrap with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min, 74% copper can be extracted in the pulp of 50 g/L scrap after 20 d. Compared with copper extractions of mesophilic culture, unacclimated culture and acclimated culture without addition of yeast extract, that of accliniated culture with addition of yeast extract is increased by 53%, 44% and 16%, respectively. In a completely stirred tank reactor, the mass fraction of copper and total iron extraction reach up to 81% and 56%, respectively. The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from electronic scrap effectively.

  15. Effects of lipids on thermophilic anaerobic digestion and reduction of lipid inhibition upon addition of bentonite.

    Science.gov (United States)

    Angelidaki, I; Petersen, S P; Ahring, B K

    1990-07-01

    The effect of bentonite-bound oil on thermophilic anaerobic digestion of cattle manure was investigated. In digestor experiments, addition of oil was found to be inhibitory during start-up and the inhibitory effect was less pronounced when the oil was added in the form of bentonite-bound oil compared to when the oil was added alone. After adaptation of the digestors, very rapid degradation of oil was observed and more than 80% of the oil was degraded within a few hours after daily feeding. In batch experiments, glyceride trioleate was found to be inhibitory to thermophilic anaerobic digestion when the concentrations were higher than 2.0 g/l. However, addition of bentonite (a clay mineral) at concentrations of 0.15% and 0.45% was found to partly overcome this inhibition. Addition of calcium chloride in concentration of 3 mM (0.033% w/v) showed a similar positive effect on the utilization of oil, but the effect was lower than with bentonite. PMID:1366749

  16. Population dynamics during startup of thermophilic anaerobic digesters: The mixing factor

    KAUST Repository

    Ghanimeh, Sophia A.

    2013-11-01

    Two thermophilic digesters were inoculated with manure and started-up under mixed and stagnant conditions. The Archaea in the mixed digester (A) were dominated by hydrogenotrophic Methanobateriaceae (61%) with most of the methane being produced via syntrophic pathways. Methanosarcinales (35%) were the only acetoclastic methanogens present. Acetate dissipation seems to depend on balanced hydrogenotrophic-to-acetotrophic abundance, which in turn was statistically correlated to free ammonia levels. Relative abundance of bacterial community was associated with the loading rate. However, in the absence of mixing (digester B), the relationship between microbial composition and operating parameters was not discernible. This was attributed to the development of microenvironments where environmental conditions are significantly different from average measured parameters. The impact of microenvironments was accentuated by the use of a non-acclimated seed that lacks adequate propionate degraders. Failure to disperse the accumulated propionate, and other organics, created high concentration niches where competitive and inhibiting conditions developed and favored undesired genera, such as Halobacteria (65% in B). As a result, digester B experienced higher acid levels and lower allowable loading rate. Mixing was found necessary to dissipate potential inhibitors, and improve stability and loading capacity, particularly when a non-acclimated seed, often lacking balanced thermophilic microflora, is used. © 2013 Elsevier Ltd.

  17. Growth characteristics of thermophile sulfate-reducing bacteria and its effect on carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Liu, T.; Liu, H.; Hu, Y.; Zhou, L.; Zheng, B. [Department of Chemistry and Engineering, Huazhong University of Science and Technology, Wuhan (China)

    2009-03-15

    Sulfate-reducing bacteria (SRB) have been identified as the main corrosive microorganisms causing unpredictable failure of materials. In this present work, a strain of thermophile SRB isolated from Bohai oilfield of China has been characterized and preliminarily identified. Furthermore, its effects on carbon steel at 60 C in SRB culture media were studied by electrochemical methods such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), and weight loss measurements. The results show that the bacteria belong to Desulfotomaculum. The optimum growth temperature and pH of the bacteria were 60 C and 7.0, respectively. Weight loss measurements suggested that the corrosion rate of carbon steel in the culture media inoculated with thermophile SRB at 60 C was 2.2 times less than that at 37 C. At 60 C, SRB shifted the freely corroding potential of carbon steel toward a more positive value in the first 10 days, which later change to a negative value. Results obtained from potentiodynamic polarization and EIS were in good agreement. The changes in biofilm structure with increase in bacteria supply offers some kind of protection to the base material in the early culture days at 60 C. Subsequently, it accelerated corrosion. Energy dispersive spectrometry (EDS) and X-ray diffraction (XRD) methods indicate that corrosion products such as iron sulfides (FeS{sub x}) in biofilm play an important role in the biocorrosion process. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  18. Survey of thermophilic Campylobacter species in cats and dogs in north-western Nigeria

    Directory of Open Access Journals (Sweden)

    Adewale Kolawale

    2010-12-01

    Full Text Available This study was conducted in north-western Nigeria to investigate the role of cats and dogs as potential reservoirs of thermophilic Campylobacter species. Faecal samples were analysed from 104 cats and 141 dogs between March 2007 and March 2009. The samples were collected from animals in households, those presented to veterinary premises and feline colonies. Campylobacter spp. were isolated from 39 (27.7% and 19 (18.3% dogs and cats, respectively. There was no significant difference in isolation rate observed between dogs (27.7% and cats (18.3% and there was also no significance difference between younger and older dogs; 23.1% (young compared to 30.3% (older dogs, but a significant difference was seen between young (4.3% and older (29.3% cats. Campylobacter upsaliensis predominated in the isolates, accounting for 89.5% and 74.4% of the positive samples in cats and dogs, respectively, C. jejuni constituted 21.1% and 23.1% of the positive samples from cats and dogs, respectively. This finding is an indication that dogs and cats frequently shed thermophilic Campylobacter spp. which could be of public health importance. To establish the zoonotic significance of canine and feline Campylobacter, isolates need to be further characterised and compared. This is the first study on the prevalence of campylobacter in cats and dogs in the region.

  19. Treatment efficiency and VFA composition of a thermophilic anaerobic contact reactor treating food industry wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Sentuerk, E.; Ince, M. [Gebze Institute of Technology, Department of Environmental Engineering, Gebze, 41400, Kocaeli (Turkey); Onkal Engin, G., E-mail: guleda@gyte.edu.tr [Gebze Institute of Technology, Department of Environmental Engineering, Gebze, 41400, Kocaeli (Turkey)

    2010-04-15

    The objective of this study was to examine the effects of organic loading rate and hydraulic retention time on volatile fatty acid composition and treatment efficiency of high rate thermophilic anaerobic contact reactor (TACR) treating potato-chips wastewaters. The operational performance of TACR was monitored from start-up by assessing chemical oxygen demand (COD) removal efficiencies, volatile fatty acid (VFA) production and biogas composition. The reactor was studied at different organic loading rates (OLRs) ranging from 0.6 to 8 kg COD/m{sup 3} d. The COD removal efficiencies were found to be 86-97% and the methane percentage of the biogas produced was 68-89% during the OLRs studied. The approximate methane yield was found to be 0.42 m{sup 3} CH{sub 4}/kg COD{sub removed}. The major intermediate products of anaerobic digestion were acetate, propionate, iso-butyrate, butyrate, iso-valerate, valerate, iso-caproate and caproate. The use of thermophilic anaerobic contact reactor offers a sustainable technology for the treatment of potato-chips wastewaters since high COD removal efficiencies and high methane percentage in the biogas produced can be attained even at high OLRs.

  20. Thermophilic campylobacters in surface waters around Lancaster, UK: negative correlation with Campylobacter infections in the community.

    Science.gov (United States)

    Jones, K; Betaieb, M; Telford, D R

    1990-11-01

    The incidence of campylobacter enteritis in Lancaster City Health Authority is three times the UK average for similar sizes of population and has marked seasonal peaks in May and June. Environmental monitoring of surface waters around Lancaster showed that thermophilic campylobacters were absent from drinking water from the fells and from the clean upper reaches of the River Conder but were present in the main rivers entering Morecambe Bay, the lower reaches of the River Conder, the Lancaster canal, and seawater from the Lune estuary and Morecambe Bay. All the surface waters tested showed the same seasonality, namely, higher numbers in the winter months and low numbers or none in May, June and July. The absence of thermophilic campylobacters in the summer months may be due to high sunshine levels because experiments on the effects of light showed that campylobacters in sewage effluent and seawater were eliminated within 60 and 30 min of daylight respectively but survived for 24 h in darkness. As the concentrations of campylobacters in surface waters were at their lowest precisely at the time of peak infections in the community it is unlikely that surface waters form Lancaster's reservoir of campylobacter infection for the community. PMID:2276990

  1. Antimicrobial Protein Candidates from the Thermophilic Geobacillus sp. Strain ZGt-1: Production, Proteomics, and Bioinformatics Analysis.

    Science.gov (United States)

    Alkhalili, Rawana N; Bernfur, Katja; Dishisha, Tarek; Mamo, Gashaw; Schelin, Jenny; Canbäck, Björn; Emanuelsson, Cecilia; Hatti-Kaul, Rajni

    2016-01-01

    A thermophilic bacterial strain, Geobacillus sp. ZGt-1, isolated from Zara hot spring in Jordan, was capable of inhibiting the growth of the thermophilic G. stearothermophilus and the mesophilic Bacillus subtilis and Salmonella typhimurium on a solid cultivation medium. Antibacterial activity was not observed when ZGt-1 was cultivated in a liquid medium; however, immobilization of the cells in agar beads that were subjected to sequential batch cultivation in the liquid medium at 60 °C showed increasing antibacterial activity up to 14 cycles. The antibacterial activity was lost on protease treatment of the culture supernatant. Concentration of the protein fraction by ammonium sulphate precipitation followed by denaturing polyacrylamide gel electrophoresis separation and analysis of the gel for antibacterial activity against G. stearothermophilus showed a distinct inhibition zone in 15-20 kDa range, suggesting that the active molecule(s) are resistant to denaturation by SDS. Mass spectrometric analysis of the protein bands around the active region resulted in identification of 22 proteins with molecular weight in the range of interest, three of which were new and are here proposed as potential antimicrobial protein candidates by in silico analysis of their amino acid sequences. Mass spectrometric analysis also indicated the presence of partial sequences of antimicrobial enzymes, amidase, and dd-carboxypeptidase. PMID:27548162

  2. Boosting dark fermentation with co-cultures of extreme thermophiles for biohythane production from garden waste.

    Science.gov (United States)

    Abreu, Angela A; Tavares, Fábio; Alves, Maria Madalena; Pereira, Maria Alcina

    2016-11-01

    Proof of principle of biohythane and potential energy production from garden waste (GW) is demonstrated in this study in a two-step process coupling dark fermentation and anaerobic digestion. The synergistic effect of using co-cultures of extreme thermophiles to intensify biohydrogen dark fermentation is demonstrated using xylose, cellobiose and GW. Co-culture of Caldicellulosiruptor saccharolyticus and Thermotoga maritima showed higher hydrogen production yields from xylose (2.7±0.1molmol(-1) total sugar) and cellobiose (4.8±0.3molmol(-1) total sugar) compared to individual cultures. Co-culture of extreme thermophiles C. saccharolyticus and Caldicellulosiruptor bescii increased synergistically the hydrogen production yield from GW (98.3±6.9Lkg(-1) (VS)) compared to individual cultures and co-culture of T. maritima and C. saccharolyticus. The biochemical methane potential of the fermentation end-products was 322±10Lkg(-1) (CODt). Biohythane, a biogas enriched with 15% hydrogen could be obtained from GW, yielding a potential energy generation of 22.2MJkg(-1) (VS).

  3. Hydrogen production from carrot pulp by the extreme thermophiles Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana

    Energy Technology Data Exchange (ETDEWEB)

    Vrije, Truus de; Budde, Miriam A.W.; Lips, Steef J.; Bakker, Robert R.; Mars, Astrid E.; Claassen, Pieternel A.M. [Wageningen UR, Food and Biobased Research, P.O. Box 17, 6700 AA Wageningen (Netherlands)

    2010-12-15

    Hydrogen was produced from carrot pulp hydrolysate, untreated carrot pulp and (mixtures of) glucose and fructose by the extreme thermophiles Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana in pH-controlled bioreactors. Carrot pulp hydrolysate was obtained after enzymatic hydrolysis of the polysaccharide fraction in carrot pulp. The main sugars in the hydrolysate were glucose, fructose, and sucrose. In fermentations with glucose hydrogen yields and productivities were similar for both strains. With fructose the hydrogen yield of C. saccharolyticus was reduced which might be related to uptake of glucose and fructose by different types of transport systems. With T. neapolitana the fructose consumption rate and consequently the hydrogen productivity were low. The hydrogen yields of both thermophiles were 2.7-2.8 mol H{sub 2}/mol hexose with 10 g/L sugars from carrot pulp hydrolysate. With 20 g/L sugars the yield of T. neapolitana was 2.4 mol H{sub 2}/mol hexose while the yield of C. saccharolyticus was reduced to 1.3 mol H{sub 2}/mol hexose due to high lactate production in the stationary growth phase. C. saccharolyticus was able to grow on carrot pulp and utilized soluble sugars and, after adaptation, pectin and some (hemi)cellulose. No growth was observed with T. neapolitana when using carrot pulp in agitated fermentations. Enzymatic hydrolysis of the polysaccharide fraction prior to fermentation increased the hydrogen yield with almost 10% to 2.3 g/kg of hydrolyzed carrot pulp. (author)

  4. Enhancement of photoheterotrophic biohydrogen production at elevated temperatures by the expression of a thermophilic clostridial hydrogenase.

    Science.gov (United States)

    Lo, Shou-Chen; Shih, Shau-Hua; Chang, Jui-Jen; Wang, Chun-Ying; Huang, Chieh-Chen

    2012-08-01

    The working temperature of a photobioreactor under sunlight can be elevated above the optimal growth temperature of a microorganism. To improve the biohydrogen productivity of photosynthetic bacteria at higher temperatures, a [FeFe]-hydrogenase gene from the thermophile Clostridium thermocellum was expressed in the mesophile Rhodopseudomonas palustris CGA009 (strain CGA-CThydA) using a log-phase expression promoter P( pckA ) to drive the expression of heterogeneous hydrogenase gene. In contrast, a mesophilic Clostridium acetobutylicum [FeFe]-hydrogenase gene was also constructed and expressed in R. palustris (strain CGA-CAhydA). Both transgenic strains were tested for cell growth, in vivo hydrogen production rate, and in vitro hydrogenase activity at elevated temperatures. Although both CGA-CThydA and CGA-CAhydA strains demonstrated enhanced growth over the vector control at temperatures above 38 °C, CGA-CThydA produced more hydrogen than the other strains. The in vitro hydrogenase activity assay, measured at 40 °C, confirmed that the activity of the CGA-CThydA hydrogenase was higher than the CGA-CAhydA hydrogenase. These results showed that the expression of a thermophilic [FeFe]-hydrogenase in R. palustris increased the growth rate and biohydrogen production at elevated temperatures. This transgenic strategy can be applied to a broad range of purple photosynthetic bacteria used to produce biohydrogen under sunlight.

  5. Xylose fermentation to biofuels (hydrogen and ethanol) by extreme thermophilic (70 C) mixed culture

    DEFF Research Database (Denmark)

    Chenxi, Zhao; Karakashev, Dimitar Borisov; Lu, W.;

    2010-01-01

    Combined biohydrogen and bioethanol (CHE) production from xylose was achieved by an extreme thermophilic (70 degrees C) mixed culture. Effect of initial pH, xylose, peptone, FeSO4, NaHCO3, yeast extract, trace mineral salts, vitamins, and phosphate buffer concentrations on bioethanol and biohydro......Combined biohydrogen and bioethanol (CHE) production from xylose was achieved by an extreme thermophilic (70 degrees C) mixed culture. Effect of initial pH, xylose, peptone, FeSO4, NaHCO3, yeast extract, trace mineral salts, vitamins, and phosphate buffer concentrations on bioethanol...... and biohydrogen yield was investigated in batch experiments. Results obtained showed that initial pH, concentration of xylose, peptone, and FeSO4 significantly affected biohydrogen and bioethanol production, while the concentration of NaHCO3 was only significant for bioethanol production. By changing cultivation......-xylose corresponding to 55% of the theoretical hydrogen yield based on acetate metabolic pathway. An empirical model was established to reveal the quantitative effect of factors significant for biohydrogen (quadratic model) production and for bioethanol (linear model) production. Changes in hydrogen/ethanol yields...

  6. Conversion of hemicellulose and D-xylose into ethanol by the use of thermophilic anaerobic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, Peter

    1998-02-01

    Ethanol is a CO{sub 2} neutral liquid fuel that can substitute the use of fossil fuels in the transportation sector, thereby reducing the CO{sub 2} emission to the atmoshpere. CO{sub 2} emission is suspected to contribute significantly to the so-called greenhouse effect, the global heating. Substrates for production of ethanol must be cheap and plentiful. This can be met by the use of lignocellulosic biomass such as willow, wheat straw, hardwood and softwood. However, the complexity of these polymeric substrates and the presence of several types of carbohydrates (glucose, xylose, mannose, galactose, arabinose) require additional treatment to release the useful carbohydrates and ferment the major carbohydrates fractions. The costs related to the ethanol-production must be kept at a minimum to be price competitive compared to gasoline. Therefore all of the carbohydrates present in lignocellulose need to be converted into ethanol. Glucose can be fermented to ethanol by yeast strains such as Saccharomyces cerevisiae, which, however, is unable to ferment the other major carbohydrate fraction, D-xylose. The need for a microorganism able to ferment D-xylose is therefore apparent. Thermophilic anaerobic ethanol producing bacteria can therefore be considered for fermentation of D-xylose. Screening of 130 thermophilic anaerobic bacterial strains, from hot-springs, mesophilic and thermophilic biogas plants, paper pulp industries and brewery waste, were examined for production of ethanol from D-xylose and wet-oxidized hemicellulose hydrolysate. Several strains were isolated and one particular strain was selected for best performance during the screening test. This strain was characterized as a new species, Thermoanaerobacter mathranii. However, the ethanol yield on wet-oxidized hemicellulose hydrolysate was not satisfactory. The bacterium was adapted by isolation of mutant strains, now resistant to the inhibitory compounds present in the hydrolysate. Growth and ethanol yield

  7. Effect of hydraulic retention time on sulfate reduction in a carbon monoxide fed thermophilic gas lift reactor

    NARCIS (Netherlands)

    Sipma, J.; Osuna, M.B.; Lettinga, G.; Stams, A.J.M.; Lens, P.N.L.

    2007-01-01

    Thermophilic hydrogenogenic carbon monoxide (CO) converting microorganisms present in anaerobic sludge play a crucial role in the application of CO as electron donor for sulfate reduction. Hydrogenogenic CO conversion was investigated in a gas lift reactor (55 °C) at different hydraulic retention ti

  8. Characterization of cytochrome P450 monooxygenase CYP154H1 from the thermophilic soil bacterium Thermobifida fusca

    NARCIS (Netherlands)

    Schallmey, Anett; den Besten, Gijs; Teune, Ite G. P.; Kembaren, Roga F.; Janssen, Dick B.

    2011-01-01

    Cytochrome P450 monooxygenases are valuable biocatalysts due to their ability to hydroxylate unactivated carbon atoms using molecular oxygen. We have cloned the gene for a new cytochrome P450 monooxygenase, named CYP154H1, from the moderately thermophilic soil bacterium Thermobifida fusca. The enzym

  9. Dispersal of thermophilic Desulfotomaculum endospores into Baltic Sea sediments over thousands of years

    DEFF Research Database (Denmark)

    Rezende, Julia Rosa de; Kjeldsen, Kasper Urup; Hubert, Casey RJ;

    2013-01-01

    a natural model for investigating passive dispersal in the ocean. We investigated the activity, diversity and abundance of thermophilic endospore-forming sulfate-reducing bacteria (SRB) in Aarhus Bay by incubating pasteurized sediment between 28 and 85°C, and by subsequent molecular diversity analyses of 16...

  10. Digestion of cattle manure under mesophilic and thermophilic conditions: characterization of organic matter applying thermal analysis and 1H NMR.

    Science.gov (United States)

    Gómez, X; Blanco, D; Lobato, A; Calleja, A; Martínez-Núñez, F; Martin-Villacorta, J

    2011-06-01

    Digestion of cattle manure collected from a livestock farm together with bedding material (straw) has been studied under mesophilic and thermophilic conditions in batch reactors. The digestion was carried out for a prolonged period with the aim of evaluating the changes undergone by the organic matter. The mesophilic digestion carried out revealed a greater capacity to produce gas and transform organic matter, while a higher conversion rate, but a lower gas yield, was obtained under thermophilic conditions. Degradation of the organic matter was evaluated by means of thermal analysis and (1)H NMR. Stabilisation through anaerobic digestion (either mesophilic or thermophilic) resulted in an increase in the quality of the organic matter, as characterised by an enrichment in thermostable compounds, and an accumulation of long chain aliphatic materials. The experiments performed demonstrated the transformation of organic matter into complex materials under anaerobic conditions with an accumulation of aliphatic components under both types of conditions tested. Degradation through mesophilic digestion, in comparison to the thermophilic process, resulted in a greater destruction of straw particles. PMID:21082330

  11. Biohydrogen production from untreated and hydrolyzed potato steam peels by the extreme thermophiles Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana

    NARCIS (Netherlands)

    Mars, A.E.; Veuskens, T.; Budde, M.A.W.; Doeveren, van P.F.N.M.; Lips, S.J.J.; Bakker, R.R.; Vrije, de G.J.; Claassen, P.A.M.

    2010-01-01

    Production of hydrogen by the extreme thermophiles Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana was studied in serum flasks and in pH-controlled bioreactors with glucose, and hydrolyzed and untreated potato steam peels (PSP) as carbon sources. Two types of PSP hydrolysates were us

  12. Solubilization of Waste Activated Sludge and Nitrogenous Compounds Transformation During Solubilization by Thermophilic Enzyme (S-TE) Process.

    Science.gov (United States)

    Yang, Qi; Luo, Kun; Li, Xiao-ming; Zhong, Yu; Chen, Hong-bo; Yang, Guo-jing; Shi, Yan-wei; Zeng, Guang-ming

    2015-06-01

    A representative thermophilic bacterial strain (AT06-1) capable of secreting protease was isolated from thermophilic aerobic digestion reactor, and 16S rRNA gene analysis indicated that it was Bacillus sp. The isolated strain was inoculated in waste activated sludge (WAS) to evaluate the performance of solubilization by thermophilic enzyme (S-TE) process under aerobic or microaerobic conditions at different temperatures (55-70 °C). Results showed that the inoculation of specific thermophilic strain significantly affected the volatile suspended solids (VSS) removal. At the optimal temperature of 65 °C, the maximum VSS removal of 43.6 % and highest SCOD of 4475 mg/L was achieved during microaerobic S-TE process. Compared to the noninoculation, more soluble protein was released during S-TE process due to the higher protease activity associated with the protein hydrolysis originated from cell lysis. The protease activity at aerobic and microaerobic S-TE process was respectively 1.73 and 1.88 times that of the noninoculation. Ammonia was the end nitrogenous compound of protein hydrolysis during S-TE process, which was stripped from the digestion system through continuous aeration.

  13. Performance and population analysis of a non-sterile trickle bed reactor inoculated with caldicellulosiruptor saccharolyticus, a thermophilic hydrogen producer

    NARCIS (Netherlands)

    Groenestijn, J.W. van; Geelhoed, J.S.; Goorissen, H.P.; Meesters, K.P.M.; Stams, A.J.M.; Claassen, P.A.M.

    2009-01-01

    Non-axenic operation of a 400 L trickle bed reactor inoculated with the thermophile Caldicellulosiruptor saccharolyticus, yielded 2.8 molH 2mol hexose converted. The reactor was fed with a complex medium with sucrose as the main substrate, continuously flushed with nitrogen gas, and operated at 73°C

  14. Formation of metabolites during biodegradation of linear alkylbenzene sulfonate in an upflow anaerobic sludge bed reactor under thermophilic conditions

    DEFF Research Database (Denmark)

    Mogensen, Anders Skibsted; Ahring, Birgitte Kiær

    2002-01-01

    Biodegradation of linear alkylbenzene sulfonate (LAS) was shown in an upflow anaerobic sludge blanket reactor under thermophilic conditions. The reactor was inoculated with granular biomass and fed with a synthetic medium and 3 mumol/L of a mixture of LAS with alkylchain length of 10 to 13 carbon...

  15. Effects of triclosan, diclofenac, and nonylphenol on mesophilic and thermophilic methanogenic activity and on the methanogenic communities

    DEFF Research Database (Denmark)

    Symsaris, Evangelos C.; Fotidis, Ioannis; Stasinakis, Athanasios S.;

    2015-01-01

    In this study, a toxicity assay using a mesophilic wastewater treatment plant sludge-based (SI) and a thermophilic manure-based inoculum (MI), under different biomass concentrations was performed to define the effects of diclofenac (DCF), triclosan (TCS), and nonylphenol (NP) on anaerobic digestion...

  16. Enhancing the Electron Transfer Capacity and Subsequent Color Removal in Bioreactors by Applying Thermophilic Anaerobic Treatment and Redox Mediators

    NARCIS (Netherlands)

    Santos, dos A.B.; Traverse, J.; Cervantes, F.J.; Lier, van J.B.

    2005-01-01

    The effect of temperature, hydraulic retention time (HRT) and the redox mediator anthraquinone-2,6-disulfonate (AQDS), on electron transfer and subsequent color removal from textile wastewater was assessed in mesophilic and thermophilic anaerobic bioreactors. The results clearly show that compared w

  17. The contribution of fermentative bacteria and methanogenic archaea to azo dye reduction by a thermophilic anaerobic consortium

    NARCIS (Netherlands)

    Santos, dos A.B.; Cervantes, F.J.; Madrid, de M.P.; Bok, de F.A.M.; Stams, A.J.M.; Lier, van J.B.

    2006-01-01

    The contribution of fermentative bacteria and methanogenic archaea to azo dye reduction by a thermophilic anaerobic consortium was studied. Additionally, the effects of different electron-donating substrates and the redox mediator riboflavin on dye reduction were assessed by using either a methanoge

  18. Biohydrogen production from desugared molasses (DM) using thermophilic mixed cultures immobilized on heat treated anaerobic sludge granules

    DEFF Research Database (Denmark)

    Kongjan, Prawit; O-Thong, Sompong; Angelidaki, Irini

    2011-01-01

    Hydrogen production from desugared molasses (DM) was investigated in both batch and continuous reactors using thermophilic mixed cultures enriched from digested manure by load shock (loading with DM concentration of 50.1 g-sugar/L) to suppress methanogens. H2 gas, free of methane, was produced du...

  19. FERMENTATION OF INULIN BY CLOSTRIDIUM-THERMOSUCCINOGENES SP-NOV, A THERMOPHILIC ANAEROBIC BACTERIUM ISOLATED FROM VARIOUS HABITATS

    NARCIS (Netherlands)

    DRENT, WJ; LAHPOR, GA; WIEGANT, WM; GOTTSCHAL, JC

    1991-01-01

    Four closely related strains of thermophilic bacteria were isolated via enrichment in batch and continuous culture with inulin as the sole source of carbon and energy by using inoculations from various sources. These new strains were isolated from beet pulp from a sugar refinery, soil around a Jerus

  20. Enrichment and detection of microorganisms involved in direct and indirect methanogenesis from methanol in an anaerobic thermophilic bioreactor

    NARCIS (Netherlands)

    Roest, de K.; Altinbas, M.; Paulo, P.L.; Heilig, H.G.H.J.; Akkermans, A.D.L.; Smidt, H.; Vos, de W.M.; Stams, A.J.M.

    2005-01-01

    To gain insight into the microorganisms involved in direct and indirect methane formation from methanol in a laboratory-scale thermophilic (55°C) methanogenic bioreactor, reactor sludge was disrupted and serial dilutions were incubated in specific growth media containing methanol and possible interm

  1. Establishment and Characterization of an Anaerobic Thermophilic (55 degrees C) Enrichment Culture Degrading Long-Chain Fatty Acids

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Ahring, Birgitte Kiær

    1995-01-01

    A thermophilic, long-chain fatty acid-oxidizing culture was enriched. Stearate was used as the substrate, and methane and carbon dioxide were the sole end products. Cultivation was possible only when a fed-batch system was used or with addition of activated carbon or bentonite. The enrichment...

  2. Paracelsin; characterization by NMR spectroscopy and circular dichroism, and hemolytic properties of a peptaibol antibiotic from the cellulolytically active mold Trichoderma reesei. Part B.

    Science.gov (United States)

    Brückner, H; Graf, H; Bokel, M

    1984-11-15

    Paracelsin, a hemolytic and membrane active polypeptide antibiotic of the peptaibol class which is excreted by the mold Trichoderma reesei, was obtained by a simplified and rapid isolation procedure utilizing hydrophobic adsorber resins. Investigation by 13C nuclear magnetic resonance spectroscopy and circular dichroism revealed considerable helical portions in solution, and the very recently accomplished sequence determination of paracelsin allows the discussion of the results with regard to the closely related analogues, alamethicin and suzukacillin. A selective cleavage of the peptide was achieved by careful treatment with various acids, and a buffer of pH 8.25 and of high ionic strength made possible the quantitative determination of the C-terminal phenylalaninol released by means of ion-exchange chromatography. The significance of the production of paracelsin and related mycotoxins of the peptaibol class, exhibiting various kinds of biological activity, is discussed with respect to the extensive effort being made towards biotechnological applications of species, strains and cellulolytically highly active mutants of the fungus Trichoderma. PMID:6500005

  3. Identification and characterization of an anaerobic ethanol-producing cellulolytic bacterial consortium from Great Basin hot springs with agricultural residues and energy crops.

    Science.gov (United States)

    Zhao, Chao; Deng, Yunjin; Wang, Xingna; Li, Qiuzhe; Huang, Yifan; Liu, Bin

    2014-09-01

    In order to obtain the cellulolytic bacterial consortia, sediments from Great Basin hot springs (Nevada, USA) were sampled and enriched with cellulosic biomass as the sole carbon source. The bacterial composition of the resulting anaerobic ethanol-producing celluloytic bacterial consortium, named SV79, was analyzed. With methods of the full-length 16S rRNA librarybased analysis and denaturing gradient gel electrophoresis, 21 bacteria belonging to eight genera were detected from this consortium. Clones with closest relation to the genera Acetivibrio, Clostridium, Cellulosilyticum, Ruminococcus, and Sporomusa were predominant. The cellulase activities and ethanol productions of consortium SV79 using different agricultural residues (sugarcane bagasse and spent mushroom substrate) and energy crops (Spartina anglica, Miscanthus floridulus, and Pennisetum sinese Roxb) were studied. During cultivation, consortium SV79 produced the maximum filter paper activity (FPase, 9.41 U/ml), carboxymethylcellulase activity (CMCase, 6.35 U/ml), and xylanase activity (4.28 U/ml) with sugarcane bagasse, spent mushroom substrate, and S. anglica, respectively. The ethanol production using M. floridulus as substrate was up to 2.63 mM ethanol/g using gas chromatography analysis. It has high potential to be a new candidate for producing ethanol with cellulosic biomass under anoxic conditions in natural environments.

  4. Isolation, Screening, and Identification of Cellulolytic Bacteria from Natural Reserves in the Subtropical Region of China and Optimization of Cellulase Production by Paenibacillus terrae ME27-1

    Directory of Open Access Journals (Sweden)

    Yan-Ling Liang

    2014-01-01

    Full Text Available From different natural reserves in the subtropical region of China, a total of 245 aerobic bacterial strains were isolated on agar plates containing sugarcane bagasse pulp as the sole carbon source. Of the 245 strains, 22 showed hydrolyzing zones on agar plates containing carboxymethyl cellulose after Congo-red staining. Molecular identification showed that the 22 strains belonged to 10 different genera, with the Burkholderia genus exhibiting the highest strain diversity and accounting for 36.36% of all the 22 strains. Three isolates among the 22 strains showed higher carboxymethyl cellulase (CMCase activity, and isolate ME27-1 exhibited the highest CMCase activity in liquid culture. The strain ME27-1 was identified as Paenibacillus terrae on the basis of 16S rRNA gene sequence analysis as well as physiological and biochemical properties. The optimum pH and temperature for CMCase activity produced by the strain ME27-1 were 5.5 and 50°C, respectively, and the enzyme was stable at a wide pH range of 5.0–9.5. A 12-fold improvement in the CMCase activity (2.08 U/mL of ME27-1 was obtained under optimal conditions for CMCase production. Thus, this study provided further information about the diversity of cellulose-degrading bacteria in the subtropical region of China and found P. terrae ME27-1 to be highly cellulolytic.

  5. Deep-Subterranean Microbial Habitats in the Hishikari Epithermal Gold Mine: Active Thermophilic Microbial Communities and Endolithic Ancient Microbial Relicts.

    Science.gov (United States)

    Hirayama, H.; Takai, K.; Inagaki, F.; Horikoshi, K.

    2001-12-01

    Deep subterranean microbial community structures in an epithermal gold-silver deposit, Hishikari gold mine, southern part of Kyusyu Japan, were evaluated through the combined use of enrichment culture methods and culture-independent molecular surveys. The geologic setting of the Hishikari deposit is composed of three lithologies; basement oceanic sediments of the Cretaceous Shimanto Supergroup, Quaternary andesites, and auriferous quartz vein. We studied the drilled core rock of these, and the geothermal hot waters from the basement aquifers collected by means of the dewatering system located at the deepest level in the mining sites. Culture-independent molecular phylogenetic analyses of PCR-amplified ribosomal DNA (rDNA) recovered from drilled cores suggested that the deep-sea oceanic microbial communities were present as ancient indigenous relicts confined in the Shimanto basement. On the other hand, genetic signals of active thermophilic microbial communities, mainly consisting of thermophilic hydrogen-oxidizer within Aquificales, thermophilic methanotroph within g-Proteobacteria and yet-uncultivated bacterium OPB37 within b-Proteobacteria, were detected with these of oceanic relicts from the subterranean geothermal hot aquifers (temp. 70-100ºC). Successful cultivation and FISH analyses strongly supported that these thermophilic lithotrophic microorganisms could be exactly active and they grew using geochemically produced hydrogen and methane gasses as nutrients. Based on these results, the deep-subsurface biosphere occurring in the Hishikari epithermal gold mine was delineated as endolithic ancient microbial relicts and modern habitats raising active lithotrophic thermophiles associated with the geological and geochemical features of the epithermal gold deposit.

  6. Enhancing xylanase production in the thermophilic fungus Myceliophthora thermophila by homologous overexpression of Mtxyr1.

    Science.gov (United States)

    Wang, Juan; Wu, Yaning; Gong, Yanfen; Yu, Shaowen; Liu, Gang

    2015-09-01

    The xylanase regulator 1 protein in Myceliophthora thermophila ATCC42464 (MtXyr1) is 60 % homologous with that of Trichoderma reesei. However, MtXyr1's regulatory role on cellulolytic and xylanolytic genes in M. thermophila is unknown. Herein, MtXyr1 was overexpressed under the control of the MtPpdc (pyruvate decarboxylase) promoter. Compared with the wild type, the extracellular xylanase activities of the transformant cultured in non-inducing and inducing media for 120 h were 25.19- and 9.04-fold higher, respectively. The Mtxyr1 mRNA level was 300-fold higher than in the wild type in corncob-containing medium. However, the filter paper activity and endoglucanase activities were unchanged in corncob-containing medium and glucose-containing medium. The different zymograms between the transformant and the wild type were analyzed and identified by mass spectrometry as three xylanases of the glycoside hydrolase (GH) family 11. Thus, overexpression of xyr1 resulted in enhanced xylanase activity in M. thermophila. Xylanase production could be improved by overexpressing Mtxyr1 in M. thermophila. PMID:26173497

  7. Thermophilic versus Mesophilic Anaerobic Digestion of Sewage Sludge: A Comparative Review

    Directory of Open Access Journals (Sweden)

    Getachew D. Gebreeyessus

    2016-06-01

    Full Text Available During advanced biological wastewater treatment, a huge amount of sludge is produced as a by-product of the treatment process. Hence, reuse and recovery of resources and energy from the sludge is a big technological challenge. The processing of sludge produced by Wastewater Treatment Plants (WWTPs is massive, which takes up a big part of the overall operational costs. In this regard, anaerobic digestion (AD of sewage sludge continues to be an attractive option to produce biogas that could contribute to the wastewater management cost reduction and foster the sustainability of those WWTPs. At the same time, AD reduces sludge amounts and that again contributes to the reduction of the sludge disposal costs. However, sludge volume minimization remains, a challenge thus improvement of dewatering efficiency is an inevitable part of WWTP operation. As a result, AD parameters could have significant impact on sludge properties. One of the most important operational parameters influencing the AD process is temperature. Consequently, the thermophilic and the mesophilic modes of sludge AD are compared for their pros and cons by many researchers. However, most comparisons are more focused on biogas yield, process speed and stability. Regarding the biogas yield, thermophilic sludge AD is preferred over the mesophilic one because of its faster biochemical reaction rate. Equally important but not studied sufficiently until now was the influence of temperature on the digestate quality, which is expressed mainly by the sludge dewateringability, and the reject water quality (chemical oxygen demand, ammonia nitrogen, and pH. In the field of comparison of thermophilic and mesophilic digestion process, few and often inconclusive research, unfortunately, has been published so far. Hence, recommendations for optimized technologies have not yet been done. The review presented provides a comparison of existing sludge AD technologies and the gaps that need to be filled so

  8. Anaerobic digestibility of Scenedesmus obliquus and Phaeodactylum tricornutum under mesophilic and thermophilic conditions

    International Nuclear Information System (INIS)

    Highlights: ► We investigate the digestion of two algae biomasses in hybrid flow-through reactors. ► We determine the bio-methane potential of these biomasses through batch assays. ► Conversion efficiencies of 20–50% with an HRT of 2.2 days are possible. ► We valorise microalgae biomass by anaerobic digestion in a high rate reactor. -- Abstract: Two types of non-axenic algal cultures, one dominated by the freshwater microalgae Scenedesmus obliquus and the other by the marine microalgae Phaeodactylum tricornutum, were cultivated in two types of simple photobioreactor systems. The production rates, expressed on dry matter (DM) basis, were in the order of 0.12 and 0.18 g DM L−1 d−1 for S. obliquus and P. tricornutum respectively. The biogas potential of algal biomass was assessed by performing standardized batch digestion as well as digestion in a hybrid flow-through reactor (combining a sludge blanket and a carrier bed), the latter under mesophilic and thermophilic conditions. Biomethane potential assays revealed the ultimate methane yield (B0) of P. tricornutum biomass to be about a factor of 1.5 higher than that of S. obliquus biomass, i.e. 0.36 and 0.24 L CH4 g−1 volatile solids (VS) added respectively. For S. obliquus biomass, the hybrid flow-through reactor tests operated at volumetric organic loading rate (Bv) of 2.8 gVS L−1 d−1 indicated low conversion efficiencies ranging between 26–31% at a hydraulic retention time (HRT) of 2.2 days for mesophilic and thermophilic conditions respectively. When digesting P. tricornutum at a Bv of 1.9 gVS L−1 d−1 at either mesophilic or thermophilic conditions and at an HRT of 2.2 days, an overall conversion efficiency of about 50% was obtained. This work indicated that the hydrolysis of the algae cells is limiting the anaerobic processing of intensively grown S. obliquus and P. tricornutum biomass.

  9. Geobacillus zalihae sp. nov., a thermophilic lipolytic bacterium isolated from palm oil mill effluent in Malaysia

    Directory of Open Access Journals (Sweden)

    Salleh Abu

    2007-08-01

    Full Text Available Abstract Background Thermophilic Bacillus strains of phylogenetic Bacillus rRNA group 5 were described as a new genus Geobacillus. Their geographical distribution included oilfields, hay compost, hydrothermal vent or soils. The members from the genus Geobacillus have a growth temperatures ranging from 35 to 78°C and contained iso-branched saturated fatty acids (iso-15:0, iso-16:0 and iso-17:0 as the major fatty acids. The members of Geobacillus have similarity in their 16S rRNA gene sequences (96.5–99.2%. Thermophiles harboring intrinsically stable enzymes are suitable for industrial applications. The quest for intrinsically thermostable lipases from thermophiles is a prominent task due to the laborious processes via genetic modification. Results Twenty-nine putative lipase producers were screened and isolated from palm oil mill effluent in Malaysia. Of these, isolate T1T was chosen for further study as relatively higher lipase activity was detected quantitatively. The crude T1 lipase showed high optimum temperature of 70°C and was also stable up to 60°C without significant loss of crude enzyme activity. Strain T1T was a Gram-positive, rod-shaped, endospore forming bacterium. On the basic of 16S rDNA analysis, strain T1T was shown to belong to the Bacillus rRNA group 5 related to Geobacillus thermoleovorans (DSM 5366T and Geobacillus kaustophilus (DSM 7263T. Chemotaxonomic data of cellular fatty acids supported the affiliation of strain T1T to the genus Geobacillus. The results of physiological and biochemical tests, DNA/DNA hybridization, RiboPrint analysis, the length of lipase gene and protein pattern allowed genotypic and phenotypic differentiation of strain T1T from its validly published closest phylogenetic neighbors. Strain T1T therefore represents a novel species, for which the name Geobacillus zalihae sp. nov. is proposed, with the type strain T1T (=DSM 18318T; NBRC 101842T. Conclusion Strain T1T was able to secrete extracellular

  10. Draft Genome Sequences of Seven Thermophilic Spore-Forming Bacteria Isolated from Foods That Produce Highly Heat-Resistant Spores, Comprising Geobacillus spp., Caldibacillus debilis, and Anoxybacillus flavithermus

    NARCIS (Netherlands)

    Berendsen, Erwin M; Wells-Bennik, Marjon H J; Krawczyk, Antonina O; de Jong, Anne; van Heel, Auke; Holsappel, Siger; Eijlander, Robyn T; Kuipers, Oscar P

    2016-01-01

    Here, we report the draft genomes of five strains of Geobacillus spp., one Caldibacillus debilis strain, and one draft genome of Anoxybacillus flavithermus, all thermophilic spore-forming Gram-positive bacteria.

  11. Draft Genome Sequences of Seven Thermophilic Spore-Forming Bacteria Isolated from Foods That Produce Highly Heat-Resistant Spores, Comprising Geobacillus spp., Caldibacillus debilis, and Anoxybacillus flavithermus

    Science.gov (United States)

    Berendsen, Erwin M.; Wells-Bennik, Marjon H. J.; Krawczyk, Antonina O.; de Jong, Anne; van Heel, Auke; Holsappel, Siger; Eijlander, Robyn T.

    2016-01-01

    Here, we report the draft genomes of five strains of Geobacillus spp., one Caldibacillus debilis strain, and one draft genome of Anoxybacillus flavithermus, all thermophilic spore-forming Gram-positive bacteria. PMID:27151781

  12. Purification and Characterization of Iso-Ribonucleases from a Novel Thermophilic Fungus

    Directory of Open Access Journals (Sweden)

    Kyle S. Landry

    2014-01-01

    Full Text Available A thermophilic fungus previously isolated from composted horse manure was found to produce extracellular iso-RNases that were purified 127.6-fold using a combination of size exclusion chromatography and a novel affinity membrane purification system. The extent of purification was determined electrophoretically using 4%–15% gradient polyacrylamide gels. RNase activity was dependent on the presence of a metal co-factor with significantly more activity with Zn2+ or Mn2+ than Mg2+. The RNases exhibited maximum activity at both pH 3.0 and pH 7.0 with no activity at pH 2.0 or 10.0. The optimal temperature for the iso-RNase was 70 °C. The molecular weight of the iso-RNase was determined to be 69 kDa using a Sephadex G-75 column.

  13. Application of thermophilic enzymes and water jet system to cassava pulp.

    Science.gov (United States)

    Chaikaew, Siriporn; Maeno, Yuka; Visessanguan, Wonnop; Ogura, Kota; Sugino, Gaku; Lee, Seung-Hwan; Ishikawa, Kazuhiko

    2012-12-01

    Co-production of fermentable sugars and nanofibrillated cellulose from cassava pulp was achieved by the combination of thermophilic enzymes (endoglucanase, β-glucosidase, and α-amylase) and a new atomization system (Star Burst System; SBS), which employs opposing water jets. The SBS represents a key technology for providing cellulose nanofibers and improving the enzymatic saccharification of cassava pulp. Depending on the enzymes used, the production of glucose from cassava pulp treated with the SBS was 1.2- to 2.5-fold higher than that from pulp not treated with the SBS. Nanofibrillated cellulose with the gel-like property in suspension was produced (yield was over 90%) by α-amylase treatment, which completely released trapped starch granules from the fibrous cell wall structure of cassava pulp pretreated with the SBS. The SBS provides an environmentally low-impact pretreatment system for processing biomass material into value-added products. PMID:23073093

  14. Genetics of thermophilic bacteria. Final progress report, May 1, 1984--April 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Welker, N.E.

    1991-12-31

    Organisms adapted to high temperature have evolved a variety of unique solutions to the biochemical problems imposed by this environment. Adaptation is commonly used to describe the biochemical properties of organisms which have become adapted to their environment (genetic adaptation). It can also mean the direct response-at the cellular level-of an organism to changes in temperature (physiological adaptation). Thermophilic bacilli (strains of Bacillus stearothermophilus) can exhibit a variety of biochemical adaptations in response to changes in temperature. These include changes in the composition and stability of the membrane, metabolic potential, the transport of amino acids, regulatory mechanisms, ribose methylation of tRNA, protein thermostability, and nutritional requirements. The objectives of the research were to develop efficient and reliable genetic systems to analyze and manipulate B. Stearothermophilus, and to use these systems initiate a biochemical, molecular, and genetic investigations of genes that are required for growth at high temperature.

  15. Isolation and Phylogenetic Analysis of Thermophile Community Within Tanjung Sakti Hot Spring, South Sumatera, Indonesia

    Directory of Open Access Journals (Sweden)

    Heni Yohandini

    2015-07-01

    Full Text Available A community of thermophiles within Tanjung Sakti Hot Spring (South Sumatera have been cultivated and identified based on 16S ribosomal RNA gene sequence. The hot spring has temperature 80C-91C and pH 7-8. We used a simple method for culturing the microbes, by enriching the spring water with nutrient broth media. Phylogenetic analysis showed that the method could recover microbes, which clustered within four distinct taxonomic groups: Anoxybacillus, Geobacillus, Brevibacillus, and Bacillus. These microbes closely related to Anoxybacillus rupiensis, Anoxybacillus flavithermus, Geobacillus pallidus, Brevibacillus thermoruber, Bacillus licheniformis, and Bacillus thermoamylovorans. The 16S ribosomal RNA gene sequence of one isolate only had 96% similarity with Brevibacillus sequence in GenBank.

  16. The Geobacillus paradox: why is a thermophilic bacterial genus so prevalent on a mesophilic planet?

    Science.gov (United States)

    Zeigler, Daniel R

    2014-01-01

    The genus Geobacillus comprises endospore-forming obligate thermophiles. These bacteria have been isolated from cool soils and even cold ocean sediments in anomalously high numbers, given that the ambient temperatures are significantly below their minimum requirement for growth. Geobacilli are active in environments such as hot plant composts, however, and examination of their genome sequences reveals that they are endowed with a battery of sensors, transporters and enzymes dedicated to hydrolysing plant polysaccharides. Although they appear to be relatively minor members of the plant biomass-degrading microbial community, Geobacillus bacteria have achieved a significant population with a worldwide distribution, probably in large part due to adaptive features of their spores. First, their morphology and resistance properties enable them to be mobilized in the atmosphere and transported long distances. Second, their longevity, which in theory may be extreme, enables them to lie quiescent but viable for long periods of time, accumulating gradually over time to achieve surprisingly high population densities.

  17. Isolation and identification of thermophilic and mesophylic proteolytic bacteria from shrimp paste "Terasi"

    Science.gov (United States)

    Murwani, R.; Supriyadi, Subagio, Trianto, A.; Ambariyanto

    2015-12-01

    Terasi is a traditional product generally made of fermented shrimp. There were many studies regarding lactic acid bacteria of terasi but none regarding proteolitic bacteria. This study was conducted to isolate and identify the thermophilic and mesophylic proteolytic bacteria from terasi. In addition, the effect of different salt concentrations on the growth of the isolated proteolytic bacteria with the greatest proteolytic activity was also studied. Terasi samples were obtained from the Northern coast region of Java island i.e. Jepara, Demak and Batang. The study obtained 34 proteolytic isolates. Four isolates were identified as Sulfidobacillus, three isolates as Vibrio / Alkaligenes / Aeromonas, two isolates as Pseudomonas, 21 isolates as Bacillus, three isolates as Kurthia/ Caryophanon and one isolates as Amphibacillus. The growth of proteolytic bacteria was affected by salt concentration. The largest growth was found at 0 ppm salt concentrations and growth was declined as salt concentration increased. Maximum growth at each salt concentration tested was found at 8 hours incubation.

  18. Thermophilic amylase from Thermus sp. isolation and its potential application for bioethanol production

    Directory of Open Access Journals (Sweden)

    Amin Fatoni

    2012-11-01

    Full Text Available Limited reserves of fossil energy stimulate researchers to explore for a new alternative energy, such as bioethanol.A thermophilic amylase producing bacterium was isolated from local hot-springs and its characteristic and potential applicationfor bioethanol production was determined. The obtained amylase was studied to determine its optimum temperature, pH,enzymatic reaction time, and substrate concentration. Tapioca waste was used as the substrate to find the potential of theamylase for degrading starch into glucose, and then the process was continued by fermentation to produce bioethanol. Theamylase producer bacterium was proposed as genus Thermus sp. The crude amylase that was obtained has the optimumtemperature of 60°C and optimum pH of 8.0, optimum substrate concentration at 10% (w/w and optimum enzymatic reactiontime of 45 minutes. These enzymes convert the starches of waste tapioca at optimum conditions, with the result of 2.9%ethanol produced from raw materials.

  19. North Western Spain hot springs are a source of lipolytic enzyme-producing thermophilic microorganisms.

    Science.gov (United States)

    Deive, Francisco J; Alvarez, María S; Sanromán, M Angeles; Longo, Maria A

    2013-02-01

    Several hot springs in Galicia (North Western Spain) have been investigated as potential sources of lipolytic enzyme-producing thermophilic microorganisms. After isolating 12 esterase producing strains, 9 of them were assured to be true lipase producers, and consequently grown in submerged cultures, obtaining high extracellular activities by two of them. Furthermore, a preliminary partial characterization of the crude lipase, obtained by ultrafiltration of the cell-free culture supernatant, was carried out at several pH and temperature values. It is outstanding that several enzymes turned out to be multiextremozymes, since they had their optimum temperature and pH at typical values from thermoalkalophiles. The thermal stability in aqueous solution of the crude enzymes was also assayed, and the influence of some potential enzyme stabilizing compounds was tested. Finally, the viability of the selected microorganisms has been demonstrated at bioreactor scale.

  20. Crystal structure of TTC0263, a thermophilic TPR protein from Thermus thermophilus HB27.

    Science.gov (United States)

    Lim, Hyosun; Kim, Kyunggon; Han, Dohyun; Oh, Jongkil; Kim, Youngsoo

    2007-08-31

    The hypothetical protein TTC0263 of Thermus thermophilus HB27 is a thermophilic tetratricopeptide repeat (TPR)-containing protein. In the present study, the TPR region (residues 26-230) was resolved at 2.5 A with R-factors of R/Rfree = 23.6%/28.6%. TTC0263 consists of 11 helices that form five TPR units. Uniquely, it contains one atypical "extended" TPR (eTPR) unit. This comprises extended helical residues near the loop region of TTC0263, such that the helical length of eTPR is longer than that of the canonical TPR sequence. In addition, the hybrid TPR domain of TTC0263 possesses oligomer-forming characteristics. TPR domains are generally involved in forming multi-subunit complexes by interacting with each other or with other subunit proteins. The dynamic structure of TTC0263 described here goes some way to explaining how TPR domains mediate the formation of multi-subunit complexes.

  1. Production and properties of an alkaline, thermophilic lipase from Pseudomonas fluorescens NS2W.

    Science.gov (United States)

    Kulkarni, N; Gadre, R V

    2002-06-01

    Eighteen bacterial strains were isolated from soil samples and screened for alkaline, thermophilic lipase production. Pseudomonas fluorescens NS2W was selected and its production of lipase was optimized in shake flasks using a statistical experimental design. Cell growth and lipase production were studied in shake flasks and in a 1-l fermenter in the optimized medium. Maximum lipase yields were 69.7 and 68.7 U ml(-1), respectively. The optimized medium resulted in about a five-fold increase in the enzyme production, compared to that obtained in the basal medium. The lipase had an optimal activity at pH 9.0 and was stable over a wide pH range of 3-11 with more than 70% activity retention. The lipase had an optimal activity at 55 degrees C and was stable up to 60 degrees C with more than 70% activity retention for at least 2 h. PMID:12032808

  2. Biotyping of thermophilic Campylobacter spp. isolated from poultry in and around Anand city, Gujarat, India

    Directory of Open Access Journals (Sweden)

    R. S. Tayde

    2014-05-01

    Full Text Available Aim: To study the prevalence of different biotypes of thermophilic Campylobacter spp. in the study area. Materials and Methods: A total of 150 samples comprising 90 chicken and 60 caecal content were collected from retail meat market and processed for isolation of Campylobacter spp. 52 Campylobacter isolates obtained from raw poultry meat (6 and caecal content (46 were subjected to biotyping using Lior's biotyping scheme. Results: Among the 52 Campylobacter isolates studied, 60.46 % isolates were identified as Campylobacter jejuni Biotype I and 39.53% were C. jejuni Biotype II, whereas 83.33 % were C. coli Biotype I and 16.66 % C. coli Biotype II. No other biotypes were identified. Conclusions: The present study revealed that C. jejuni Biotype I was more prevalent than Biotype II whereas in case of C. coli, Biotype I was more prevalent than Biotype II providing basis for further epidemiological study.

  3. Microbial biofilm community in a thermophilic trickling bio filter used for continuous biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Y.; Park, E.-J. [Korea Advanced Inst. of Science and Technology, Daejeon (Korea, Republic of). Dept. of Chemical and Biomolecular Engineering; Oh, Y.-K. [Pusan National Univ., Pusan (Korea, Republic of). Dept. of Chemical Engineering; Park, S. [Pusan National Univ., Pusan (Korea, Republic of). Dept. of Chemical Engineering]|[Pusan National Univ., Pusan (Korea, Republic of). Inst. for Environmental Technology and Industry

    2004-07-01

    The microbial community in a thermophilic trickling biofilter reactor (TBR) that produces biohydrogen was examined. In particular, nonculture-based molecular methods were used to characterize the microbial community in the biofilm formed on the matrixes that were packed in the reactor. The operation of the bioreactor was described. TBR demonstrated long term stability to produce hydrogen. Biomass volatile suspended solids (VSS) in the TBR decreased gradually as bed height increased from the bottom of the bed. Epifluorescence microscopy of 6-diamidino-2-phenylindole (DAPI)-stained cells and denaturing gradient gel electrophoresis (DGGE) analysis both indicate that microbial composition changes in the TBR according to bed height. The dominant phylogenetic groups in the system were identified along with the comparative analysis of morphology of microbial community and the DGGE profiles of the microbial community in terms of total genomic DNA extracted from biofilm cells. 10 refs., 1 tab., 5 figs.

  4. Bioleaching of chalcopyrite and bornite by moderately thermophilic bacteria:an emphasis on their interactions

    Institute of Scientific and Technical Information of China (English)

    Hong-bo Zhao; Jun Wang; Xiao-wen Gan; Wen-qing Qin; Ming-hao Hu; Guan-zhou Qiu

    2015-01-01

    Interactions between chalcopyrite and bornite during bioleaching by moderately thermophilic bacteria were investigated mainly by X-ray diffraction, scanning electron microscopy, and electrochemical measurements performed in conjunction with bioleaching experiments. The results showed that a synergistic effect existed between chalcopyrite and bornite during bioleaching by bothAcidithiobacillus caldus and Leptospirillum ferriphilum and that extremely high copper extraction could be achieved when chalcopyrite and bornite coexisted in a bioleaching system. Bornite dissolved preferentially because of its lower corrosion potential, and its dissolution was accelerated by the gal-vanic current during the initial stage of bioleaching. The galvanic current and optimum redox potential of 390−480 mV vs. Ag/AgCl pro-moted the reduction of chalcopyrite to chalcocite (Cu2S), thus accelerating its dissolution.

  5. Effect of oxygen on the microbial activities of thermophilic anaerobic biomass.

    Science.gov (United States)

    Pedizzi, C; Regueiro, L; Rodriguez-Verde, I; Lema, J M; Carballa, M

    2016-07-01

    Low oxygen levels (μgO2L(-1)) in anaerobic reactors are quite common and no relevant consequences are expected. On the contrary, higher concentrations could affect the process. This work aimed to study the influence of oxygen (4.3 and 8.8mgO2L(-1), respectively) on the different microbial activities (hydrolytic, acidogenic and methanogenic) of thermophilic anaerobic biomass and on the methanogenic community structure. Batch tests in presence of oxygen were conducted using specific substrates for each biological activity and a blank (with minimum oxygen) was included. No effect of oxygen was observed on the hydrolytic and acidogenic activities. In contrast, the methane production rate decreased by 40% in all oxygenated batches and the development of active archaeal community was slower in presence of 8.8mgO2L(-1). However, despite this sensitivity of methanogens to oxygen at saturation levels, the inhibition was reversible. PMID:27020398

  6. Quantitative risk assessment of human campylobacteriosis associated with thermophilic Campylobacter species in chickens

    DEFF Research Database (Denmark)

    Rosenquist, Hanne; Nielsen, N. L.; Sommer, Helle Mølgaard;

    2003-01-01

    A quantitative risk assessment comprising the elements hazard identification, hazard characterization, exposure assessment, and risk characterization has been prepared to assess the effect of different mitigation strategies on the number of human cases in Denmark associated with thermophilic...... Campylobacter spp. in chickens. To estimate the human exposure to Campylobacter from a chicken meal and the number of human cases associated with this exposure, a mathematical risk model was developed. The model details the spread and transfer of Campylobacter in chickens from slaughter to consumption and the...... covers the transfer of Campylobacter during food handling in private kitchens. The age and sex of consumers were included in this module to introduce variable hygiene levels during food preparation and variable sizes and compositions of meals. Finally, the outcome of the exposure assessment modules was...

  7. Bioleaching of chalcopyrite and bornite by moderately thermophilic bacteria: an emphasis on their interactions

    Science.gov (United States)

    Zhao, Hong-bo; Wang, Jun; Gan, Xiao-wen; Qin, Wen-qing; Hu, Ming-hao; Qiu, Guan-zhou

    2015-08-01

    Interactions between chalcopyrite and bornite during bioleaching by moderately thermophilic bacteria were investigated mainly by X-ray diffraction, scanning electron microscopy, and electrochemical measurements performed in conjunction with bioleaching experiments. The results showed that a synergistic effect existed between chalcopyrite and bornite during bioleaching by both Acidithiobacillus caldus and Leptospirillum ferriphilum and that extremely high copper extraction could be achieved when chalcopyrite and bornite coexisted in a bioleaching system. Bornite dissolved preferentially because of its lower corrosion potential, and its dissolution was accelerated by the galvanic current during the initial stage of bioleaching. The galvanic current and optimum redox potential of 390-480 mV vs. Ag/AgCl promoted the reduction of chalcopyrite to chalcocite (Cu2S), thus accelerating its dissolution.

  8. Amylase production in solid state fermentation by the thermophilic fungus Thermomyces lanuginosus.

    Science.gov (United States)

    Kunamneni, Adinarayana; Permaul, Kugen; Singh, Suren

    2005-08-01

    The production of extracellular amylase by the thermophilic fungus Thermomyces lanuginosus was studied in solid state fermentation (SSF). Solid substrates such as wheat bran, molasses bran, rice bran, maize meal, millet cereal, wheat flakes, barley bran, crushed maize, corncobs and crushed wheat were studied for enzyme production. Growth on wheat bran gave the highest amylase activity. The maximum enzyme activity obtained was 534 U/g of wheat bran under optimum conditions of an incubation period of 120 h, an incubation temperature of 50 degrees C, an initial moisture content of 90%, a pH of 6.0, an inoculum level of 10% (v/w), a salt solution concentration of 1.5:10 (v/w) and a ratio of substrate weight to flask volume of 1:100 with soluble starch (1% w/w) and peptone (1% w/w) as supplements. PMID:16198259

  9. Performance optimization and validation of ADM1 simulations under anaerobic thermophilic conditions

    KAUST Repository

    Atallah, Nabil M.

    2014-12-01

    In this study, two experimental sets of data each involving two thermophilic anaerobic digesters treating food waste, were simulated using the Anaerobic Digestion Model No. 1 (ADM1). A sensitivity analysis was conducted, using both data sets of one digester, for parameter optimization based on five measured performance indicators: methane generation, pH, acetate, total COD, ammonia, and an equally weighted combination of the five indicators. The simulation results revealed that while optimization with respect to methane alone, a commonly adopted approach, succeeded in simulating methane experimental results, it predicted other intermediary outputs less accurately. On the other hand, the multi-objective optimization has the advantage of providing better results than methane optimization despite not capturing the intermediary output. The results from the parameter optimization were validated upon their independent application on the data sets of the second digester.

  10. The effects of a thermophile metabolite, tryptophol, upon protecting shrimp against white spot syndrome virus.

    Science.gov (United States)

    Zhu, Fei; Jin, Min

    2015-12-01

    White spot syndrome virus (WSSV) is a shrimp pathogen responsible for significant economic loss in commercial shrimp farms and until now, there has been no effective approach to control this disease. In this study, tryptophol (indole-3-ethanol) was identified as a metabolite involved in bacteriophage-thermophile interactions. The dietary addition of tryptophol reduced the mortality in shrimp Marsupenaeus japonicus when orally challenged with WSSV. Our results revealed that 50 mg/kg tryptophol has a better protective effect in shrimp than 10 or 100 mg/kg tryptophol. WSSV copies in shrimp were reduced significantly (P shrimp, and thus holds significant promise as a novel and efficient therapeutic approach to control WSSV in shrimp aquaculture.

  11. Expression, purification, and characterization of a thermophilic neutral protease from Bacillus stearothermophilus in Bacillus subtilis

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The gene coding for a thermophilic neutral protease from Bacillus stearothermophilus was expressed in Bacillus subtilis DB104, under the control of the sacB gene promoter. This was followed by either the native signal peptide sequence of this protease or the signal peptide sequence of the sacB gene. The protease was purified 3.8-fold, with a specific activity of 16530 U mg-1. As analyzed by SDS-PAGE, the molecular mass of the expressed protease was about 35 kDa, and the optimal temperature and pH of the protease were 65℃ and 7.5, respectively. Moreover, it still had about 80% activity after 1 h reaction at 65℃.

  12. Expression, purification, and characterization of a thermophilic neutral protease from Bacillus stearothermophilus in Bacillus subtilis

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The gene coding for a thermophilic neutral protease from Bacillus stearothermophilus was expressed in Bacillus subtilis DB104, under the control of the sacB gene promoter. This was followed by either the native signal peptide sequence of this protease or the signal peptide sequence of the sacB gene. The protease was purified 3.8-fold, with a specific activity of 16530 U mg-1. As analyzed by SDS-PAGE, the molecular mass of the expressed protease was about 35 kDa, and the optimal temperature and pH of the protease were 65℃ and 7.5, respectively. Moreover, it still had about 80% activity after 1 h reaction at 65 ℃ .

  13. The glutathione response to salt stress in the thermophilic fungus thermomyces lanuginosus

    DEFF Research Database (Denmark)

    Friborg Jepsen, Helene; Posci, Istvan; Jensen, Bo

    2008-01-01

    and in the basal medium. Due to the osmotic and ionic stress imposed by the salts, the growth of T. lanuginosus was delayed and the inhibitory effect of KCl exceeded that of NaCl. Glutathione seemed to be involved in the response of T. lanuginosus towards high concentrations of salt, as the level of stress......In order to investigate the role of glutathione in response to salt stress in the thermophilic fungus, Thermomyces lanuginosus, the biomass and the intracellular pool of protein and the glutathione + glutathione disulphid (GSH + GSSG) was measured for four days in a medium with NaCl or KCl added...... was negatively correlated with the amount of total glutathione. Salt stress did not result in an increased intracellular protein production. GSH accumulated while nutrients were abundant and were subsequently degraded later, suggesting that nutrients stored in GSH are used when the medium is depleted....

  14. Strategies for recovering inhibition caused by long chain fatty acids on anaerobic thermophilic biogas reactors

    DEFF Research Database (Denmark)

    Palatsi, J.; Laureni, M.; Andres, M.V.;

    2009-01-01

    and reducing the bioavailable LCFA concentration, were found to be the best recovery strategies, improving the recovery time from 10 to 2 days, in semi-continuously fed systems. Moreover, acclimatization was introduced by repeated inhibition and process recovery. The subsequent exposure of the anaerobic......Long chain fatty acids (LCFA) concentrations over 1.0 g L1 were inhibiting manure thermophilic digestion, in batch and semi-continuous experiments, resulting in a temporary cease of the biogas production. The aim of the work was to test and evaluate several recovery actions, such as reactor feeding...... patterns, dilution and addition of adsorbents, in order to determine the most appropriate strategy for fast recovery of the reactor activity in manure based plants inhibited by LCFA. Dilution with active inoculum for increasing the biomass/LCFA ratio, or addition of adsorbents for adsorbing the LCFA...

  15. High thermal stability and unique trimer formation of cytochrome c' from thermophilic Hydrogenophilus thermoluteolus.

    Science.gov (United States)

    Fujii, Sotaro; Masanari, Misa; Inoue, Hiroki; Yamanaka, Masaru; Wakai, Satoshi; Nishihara, Hirofumi; Sambongi, Yoshihiro

    2013-01-01

    Sequence analysis indicated that thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) and its mesophilic homolog, Allochromatium vinosum cytochrome c' (AVCP), closely resemble each other in a phylogenetic tree of the cytochrome c' family, with 55% sequence identity. The denaturation temperature of PHCP was 87 °C, 35 °C higher than that of AVCP. Furthermore, PHCP exhibited a larger enthalpy change value during its thermal denaturation than AVCP. While AVCP was dimeric, as observed previously, PHCP was trimeric, and this was the first observation as a cytochrome c'. Dissociation of trimeric PHCP and its protein denaturation reversibly occurred at the same time in a two-state transition manner. Therefore, PHCP is enthalpically more stable than AVCP, perhaps due to its unique trimeric form, in addition to the lower number of Gly residues in its putative α-helical regions.

  16. Development of a gene cloning system in a fast-growing and moderately thermophilic Streptomyces species and heterologous expression of Streptomyces antibiotic biosynthetic gene clusters

    Directory of Open Access Journals (Sweden)

    Qin Zhongjun

    2011-10-01

    Full Text Available Abstract Background Streptomyces species are a major source of antibiotics. They usually grow slowly at their optimal temperature and fermentation of industrial strains in a large scale often takes a long time, consuming more energy and materials than some other bacterial industrial strains (e.g., E. coli and Bacillus. Most thermophilic Streptomyces species grow fast, but no gene cloning systems have been developed in such strains. Results We report here the isolation of 41 fast-growing (about twice the rate of S. coelicolor, moderately thermophilic (growing at both 30°C and 50°C Streptomyces strains, detection of one linear and three circular plasmids in them, and sequencing of a 6996-bp plasmid, pTSC1, from one of them. pTSC1-derived pCWH1 could replicate in both thermophilic and mesophilic Streptomyces strains. On the other hand, several Streptomyces replicons function in thermophilic Streptomyces species. By examining ten well-sporulating strains, we found two promising cloning hosts, 2C and 4F. A gene cloning system was established by using the two strains. The actinorhodin and anthramycin biosynthetic gene clusters from mesophilic S. coelicolor A3(2 and thermophilic S. refuineus were heterologously expressed in one of the hosts. Conclusions We have developed a gene cloning and expression system in a fast-growing and moderately thermophilic Streptomyces species. Although just a few plasmids and one antibiotic biosynthetic gene cluster from mesophilic Streptomyces were successfully expressed in thermophilic Streptomyces species, we expect that by utilizing thermophilic Streptomyces-specific promoters, more genes and especially antibiotic genes clusters of mesophilic Streptomyces should be heterologously expressed.

  17. Isolation and Characterization of a Thermophilic Oil-Degrading Bacterial Consortium

    Institute of Scientific and Technical Information of China (English)

    Gu Guizhou; Li Zheng; Zhao Dongfeng; Zhao Chaocheng

    2013-01-01

    In this study, a thermophilic oil-degrading bacterial consortium KO8-2 growing within the temperature range of 45-65℃(with 55℃being the optimum temperature) was isolated from oil-contaminated soil of Karamay in Xinjiang, China. Denaturing gradient gel electrophoresis (DGGE) showed that there were nine strains included in KO8-2, which originated from the genera of Bacillus, Geobacillus and Clostridium. They all belonged to thermophilic bacteria, and had been previously proved as degraders of at least one petroleum fraction. The crude oil degraded by KO8-2 was analyzed by infrared spectrophotometry, hydrocarbon group type analysis and gas chromatography. The results indicated that the bacterial consortium KO8-2 was able to utilize 64.33%of saturates, 27.06%of aromatics, 13.24%of resins and the oil removal efifciency reached up to 58.73%at 55℃when the oil concentration was 10 g/L. Detailed analysis showed that KO8-2 was able to utilize the hydrocarbon components before C19, and the n-alkanes ranging from C20-C33 were signiif-cantly degraded. The ratios of nC17/Pr and nC18/Ph were 3.12 and 3.87, respectively, before degradation, whereas after degradation the ratios reduced to 0.21 and 0.38, respectively. Compared with the control sample, the oil removal efifciency in KO8-2 composting reactor reached 50.12%after a degradation duration of 60 days.

  18. Geochemistry meets Biochemistry: Minimal Metabolic Systems in Extremely Thermophilic Bacteria from Geothermal Environments.

    Science.gov (United States)

    Robb, F. T.; DiRuggiero, J.; Davila, J.; Schwartz, M.

    2002-05-01

    A growing body of research confirms that extreme thermophiles can grow at temperatures of at least 113.5oC, at elevated pressures. Other archaeal isolates can thrive in hostile chemical conditions, for example pH 0.8. We, and others have shown that hyperthermophiles have novel heat shock proteins and other chaperonins that permit them to maintain native protein structures in unfavorable conditions. They are also able to survive using individual gases and gas mixtures We have determined the complete genome sequence of a bacterial isolate from thermal mats on the Kamchatka Peninsula that grows on a salts medium with carbon monoxide as its sole energy and carbon source. It forms hydrogen in proportion with CO consumption. The minimal size of its genome, 2.1 megabase pairs, and its ability to form spores have led us to propose that this autotrophic bacterium can serve as a model for ancestral microbial cells. We have isolated a new class of thermophilic, extremely radiation resistant bacteria from Yellowstone National Park that can withstand space vacuum for extended periods. In collaboration with NASA Goddard, we have exposed filters coated with one of these isolates to space vacuum and to extreme UV during a sounding rocket flight at White Sands. Deinococcus radiodurans, the most desiccation and radiation resistant organism characterized so far, was exposed as a control. The new isolate was slightly more desiccation resistant than D. radiodurans, and significantly more resistant than D. radiodurans to extreme UV at 34 nm. These studies may provide insights into the potential for viable bacterial cells to survive transmission through space, a phenomenon usually referred to as panspermia.

  19. Enhancement of thermophilic anaerobic digestion of thickened waste activated sludge by combined microwave and alkaline pretreatment

    Institute of Scientific and Technical Information of China (English)

    Yongzhi Chi; Yuyou Li; Xuening Fei; Shaopo Wang; Hongying Yun

    2011-01-01

    Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to improve thermophilic anaerobic digestion efficiency.Uniform design was applied to determine the combination of target temperature (110-210℃),microwave holding time (1-51 min),and NaOH dose (0-2.5 g NaOH/g suspended solids (SS)) in terms of their effect on volatile suspended solids (VSS) solubilization.Maximum solubilization ratio (85.1%) of VSS was observed at 210℃ with 0.2 g-NaOH/g-SS and 35 min holding time.The effects of 12 different pretreatment methods were investigated in 28 thermophilic batch reactors by monitoring cumulative methane production (CMP).Improvements in methane production in the TWAS were directly related to the microwave and alkaline pretreatment of the sludge.The highest CMP was a 27% improvement over the control.In spite of the increase in soluble chemical oxygen demand concentration and the decrease in dewaterability of digested sludge,a semi-continuous thennophilic reactor fed with pretreated TWAS without neutralization (at 170℃ with 1 rain holding time and 0.05 g NaOH/g SS) was stable and functioned well,with volatile solid (VS) and total chemical oxygen demand (TCOD) reductions of 28% and 18%,respectively,which were higher than those of the control system.Additionally,methane yields (L@STP/g-CODadded,at standard temperature and pressure (STP) conditions of 0℃ and 101.325 kPa) and (L@STP/g VSadded) increased by 17% and 13%,respectively,compared to the control reactor.

  20. Start-up strategies for thermophilic anaerobic digestion of pig manure

    International Nuclear Information System (INIS)

    Sludge physicochemical composition, methane (CH4) yield, and methanogenic community structure and dynamics using quantitative real-time polymerase chain reaction were determined after start-up of anaerobic digestion of pig manure. Eight thermophilic continuous stirred anaerobic digesters were used during 126 days. Four management strategies were investigated: a feedless and a non-feedless period followed by a gradual or an abrupt addition of pig manure (two digesters per strategy). During the first 43 days, VFA (volatile fatty acids) accumulations and low CH4 yield were observed in all digesters. After this period, digesters recovered their initial status being propionic acid the last parameter to be re-established. Non-feedless digesters with an abrupt addition of pig manure showed the best performances (lower VFA accumulation and higher CH4 yield). Differences in microbial orders and dynamics, however, were less evident among treatments. Hydrogenotrophic methanogenesis, Methanomicrobiales first and Methanobacteriales second, was the dominant metabolic pathway in all digesters. Further research is needed to clarify the role and activity of hydrogenotrophic methanogens during the recovery start-up period and to identify the best molecular tools and methodologies to monitor microbial populations and dynamics reliably and accurately in anaerobic digesters. - Highlights: • Four start-up strategies for thermophilic anaerobic digestion of pig manure were tested. • Physicochemical composition, methane yield and methanogenic community were determined. • During the first 43 days, a decline in reactor's performance occurred. • The best start-up strategy was non-feedless with an abrupt addition of pig slurry. • Hydrogenotrophic methanogenesis was the dominant metabolic pathway

  1. Biochemical characterization of a thermostable HNH endonuclease from deep-sea thermophilic bacteriophage GVE2.

    Science.gov (United States)

    Zhang, Likui; Huang, Yanchao; Xu, Dandan; Yang, Lixiang; Qian, Kaicheng; Chang, Guozhu; Gong, Yong; Zhou, Xiaojian; Ma, Kesen

    2016-09-01

    His-Asn-His (HNH) proteins are a very common family of small nucleic acid-binding proteins that are generally associated with endonuclease activity and are found in all kingdoms of life. Although HNH endonucleases from mesophiles have been widely investigated, the biochemical functions of HNH endonucleases from thermophilic bacteriophages remain unknown. Here, we characterized the biochemical properties of a thermostable HNH endonuclease from deep-sea thermophilic bacteriophage GVE2. The recombinant GVE2 HNH endonuclease exhibited non-specific cleavage activity at high temperature. The optimal temperature of the GVE2 HNH endonuclease for cleaving DNA was 60-65 °C, and the enzyme retained its DNA cleavage activity even after heating at 100 °C for 30 min, suggesting the enzyme is a thermostable endonuclease. The GVE2 HNH endonuclease cleaved DNA over a wide pH spectrum, ranging from 5.5 to 9.0, and the optimal pH for the enzyme activity was 8.0-9.0. Furthermore, the GVE2 HNH endonuclease activity was dependent on a divalent metal ion. While the enzyme is inactive in the presence of Cu(2+), the GVE2 HNH endonuclease displayed cleavage activity of varied efficiency with Mn(2+), Mg(2+), Ca(2+), Fe(2+), Co(2+), Zn(2+), and Ni(2+). The GVE2 HNH endonuclease activity was inhibited by NaCl. This study provides the basis for determining the role of this endonuclease in life cycle of the bacteriophage GVE2 and suggests the potential application of the enzyme in molecular biology and biotechnology. PMID:27131500

  2. Purification and properties of thermostable tryptophanase from an obligately symbiotic thermophile, Symbiobacterium thermophilum.

    Science.gov (United States)

    Suzuki, S; Hirahara, T; Horinouchi, S; Beppu, T

    1991-12-01

    A thermostable tryptophanase was extracted from a thermophilic bacterium, Symbiobacterium thermophilum strain T, which is obligately symbiotic with the thermophilic Bacillus strain S. The enzyme was purified 21-fold to homogeneity with 19% recovery by a series of chromatographies using anion-exchange, hydroxylapatite, hydrophobic interaction, and MonoQ anion-exchange columns. The molecular weight of the purified enzyme was estimated to be approximately 210,000 by gel filtration, while the molecular weight of its subunit was 46,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which indicates that the native enzyme is composed of four homologous subunits. The isoelectric point of the enzyme was 4.9. The tryptophanase was stable to heating at 65 degrees C for 20 min and the optimum temperature for the enzyme activity for 20 min reaction was 70 degrees C. The optimum pH was 7.0. The NH2-terminal amino acid sequence of this tryptophanase shows similarity to that of Escherichia coli K-12, despite a great difference in the thermostability of these two enzymes. The purified enzyme catalyzed the degradation (alpha, beta-elimination) of L-tryptophan into indole, pyruvate, and ammonia in the presence of pyridoxal-5'-phosphate. The Km value for L-tryptophan was 1.47 mM. 5-Hydroxy-L-tryptophan, 5-methyl-DL-tryptophan, L-cysteine, S-methyl-L-cysteine, and L-serine were also used as substrates and converted to pyruvate. The reverse reaction of alpha, beta-elimination of this tryptophanase produced L-tryptophan from indole and pyruvate in the presence of a high concentration of ammonium acetate.

  3. Antimicrobial susceptibility profiles of thermophilic campylobacters isolated from patients in the town of Niš

    Directory of Open Access Journals (Sweden)

    Miljković-Selimović Biljana

    2009-01-01

    Full Text Available Background/Aim. In some clinical forms of human Campylobacter infections, such as prolonged diarrhea or associated with postinfections sequels, antibacterial treatment is necessary. The aim of the present study was to evaluate the antimicrobial susceptibility of thermophilic Campylobacter strains isolated from patients with diarrhea, as well as from patients with diarrhea followed by postinfections sequels, to drugs used in the therapy of enterocolitis, and to nalidixic acid used in laboratory identification and differentiation of thermophilic Campylobacter spp. Methods. We studied the antimicrobial susceptibility profiles of 131 Campylobacter strains isolated from patients with diarrhea (122 strains, diarrhea associated with rheumatic disorders (8 strains, and one strain isolated from a patient with Guillain-Barré Syndrome following Campylobacter enterocolitis. Susceptibility testing to erythromycin, gentamicin, tetracycline, chloramphenicol, ciprofloxacin and nalidixic acid was performed by the agar dilution method. Results. In the strains we investigated, resistance to gentamicin and chloramphenicol was not recorded, whereas a low rate of strains resistant to erythromycin (2.4%, a higher prevalence of strains resistant to tetracycline (9.9%, and a high level of resistance to ciprofloxacin (29.8% and nalidixic acid (33.3% were registered. All strains resistant to nalidixic acid were also resistant to ciprofloxacin. In addition, there was no difference in the occurrence of resistance between strains isolated from patients with diarrhea as compared to those isolated from patients with diarrhea followed by postinfection disorders. Conclusion. The fact that the most of Campylobacter strains were sensitive to erythromycin and all to gentamicin, makes erythromycin an antibiotic of choice in the treatment of Campylobacter diarrhea and gentamicin when parenteral therapy should be administered. Resistance to tetracycline and, especially, ciprofloxacin

  4. A novel ecological role of the Firmicutes identified in thermophilic microbial fuel cells.

    Science.gov (United States)

    Wrighton, Kelly C; Agbo, Peter; Warnecke, Falk; Weber, Karrie A; Brodie, Eoin L; DeSantis, Todd Z; Hugenholtz, Philip; Andersen, Gary L; Coates, John D

    2008-11-01

    Significant effort is currently focused on microbial fuel cells (MFCs) as a source of renewable energy. Most studies concentrate on operation at mesophilic temperatures. However, anaerobic digestion studies have reported on the superiority of thermophilic operation and demonstrated a net energy gain in terms of methane yield. As such, our studies focused on MFC operation and microbiology at 55 degrees C. Over a 100-day operation, these MFCs were stable and achieved a power density of 37 mW m(-2) with a coulombic efficiency of 89%. To infer activity and taxonomic identity of dominant members of the electricity-producing community, we performed phylogenetic microarray and clone library analysis with small subunit ribosomal RNA (16S rRNA) and ribosomal RNA gene (16S rDNA). The results illustrated the dominance (80% of clone library sequences) of the Firmicutes in electricity production. Similarly, rRNA sequences from Firmicutes accounted for 50% of those taxa that increased in relative abundance from current-producing MFCs, implying their functional role in current production. We complemented these analyses by isolating the first organisms from a thermophilic MFC. One of the isolates, a Firmicutes Thermincola sp. strain JR, not only produced more current than known organisms (0.42 mA) in an H-cell system but also represented the first demonstration of direct anode reduction by a member of this phylum. Our research illustrates the importance of using a variety of molecular and culture-based methods to reliably characterize bacterial communities. Consequently, we revealed a previously unidentified functional role for Gram-positive bacteria in MFC current generation. PMID:18769460

  5. [Cobalt(III)-EDTA]- Reduction by Thermophilic Methanogen Methanothermobacter Thermautotrophicus

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Rajesh [Miami Univ., Oxford, OH (United States); Dong, Hailiang [Miami Univ., Oxford, OH (United States); China Univ. of Geosciences, Beijing (China); Liu, Deng [Miami Univ., Oxford, OH (United States); China Univ. of Geosciences, Wuhan (China); Marts, Amy R. [Miami Univ., Oxford, OH (United States); Tierney, David L. [Miami Univ., Oxford, OH (United States); Almquist, Catherine B. [Miami Univ., Oxford, OH (United States)

    2015-06-30

    Cobalt is a metal contaminant at high temperature radioactive waste disposal sites. In previous studies have largely focused on mesophilic microorganisms to remediate cobalt, despite the presence of thermophilic microorganisms at such sites. In this study,Methanothermobacter thermautotrophicus, a thermophilic methanogen, was used to reduce Co(III) in the form of [Co(III)–EDTA]-. Bioreduction experiments were conducted in a growth medium with H2/CO2 as a growth substrate at initial Co(III) concentrations of 1, 2, 4, 7, and 10 mM. At low Co(III) concentrations (< 4 mM), a complete reduction was observed within a week. Wet chemistry, X-ray absorption near-edge structure (XANES) and electron paramagnetic resonance (EPR) analyses were all consistent in revealing the reduction kinetics. But, at higher concentrations (7 and 10 mM) the reduction extents only reached 69.8% and 48.5%, respectively, likely due to the toxic effect of Co(III) to the methanogen cells as evidenced by a decrease in total cellular protein at these Co(III) concentrations. Methanogenesis was inhibited by Co(III) bioreduction, possibly due to impaired cell growth and electron diversion from CO2 to Co(III). Overall, our results demonstrated the ability of M. thermautotrophicus to reduce Co(III) to Co(II) and its potential application for remediating 60Co contaminant at high temperature subsurface radioactive waste disposal sites.

  6. Determination of the kinetic parameters of the phenol-degrading thermophile Bacillus themoleovorans sp. A2.

    Science.gov (United States)

    Feitkenhauer, H; Schnicke, S; Müller, R; Märkl, H

    2001-12-01

    Phenolic compounds are pollutants in many wastewaters, e.g. from crude oil refineries, coal gasification plants or olive oil mills. Phenol removal is a key process for the biodegradation of pollutants at high temperatures because even low concentrations of phenol can inhibit microorganisms severely. Bacillus thermoleovorans sp. A2, a recently isolated thermophilic strain (temperature optimum 65 degrees C), was investigated for its capacity to degrade phenol. The experiments revealed that growth rates were about four times higher than those of mesophilic microorganisms such as Pseudomonas putida. Very high specific growth rates of 2.8 h(-1) were measured at phenol concentrations of 15 mg/l, while at phenol concentrations of 100-500 mg/l growth rates were still in the range of 1 h(-1). The growth kinetics of the thermophilic Bacillus thermoleovorans sp. A2 on phenol as sole carbon and energy source can be described using a three-parameter model developed in enzyme kinetics. The yield coefficient Yx/s of 0.8-1 g cell dry weight/g phenol was considerably higher than cell yields of mesophilic bacteria (Yx/s 0.40-0.52 g cell dry weight/g phenol). The highest growth rate was found at pH 6. Bacillus thermoleovorans sp. A2 was found to be insensitive to hydrodynamic shear stress in stirred bioreactor experiments (despite possible membrane damage caused by phenol) and flourished at an ionic strength of the medium of 0.25(-1) mol/l (equivalent to about 15-60 g NaCl/l). These exceptional properties make Bacillus thermoleovorans sp. A2 an excellent candidate for technical applications.

  7. Cellulolytic potential of probiotic Bacillus Subtilis AMS6 isolated from traditional fermented soybean (Churpi): An in-vitro study with regards to application as an animal feed additive.

    Science.gov (United States)

    Manhar, Ajay K; Bashir, Yasir; Saikia, Devabrata; Nath, Dhrubajyoti; Gupta, Kuldeep; Konwar, Bolin K; Kumar, Rahul; Namsa, Nima D; Mandal, Manabendra

    2016-01-01

    The aim of the present study is to evaluate the probiotic attributes of Bacillus subtilis AMS6 isolated from fermented soybean (Churpi). This isolate exhibited tolerance to low pH (pH 2.0) and bile salt (0.3%), capability to autoaggregate and coaggregate. AMS6 also showed highest antibacterial activity against the pathogenic indicator strain Salmonella enterica typhimurium (MTCC 1252) and susceptibility towards different antibiotics tested. The isolate was effective in inhibiting the adherence of food borne pathogens to Caco-2 epithelial cell lines, and was also found to be non-hemolytic which further strengthen the candidature of the isolate as a potential probiotic. Further studies revealed B. subtilis AMS6 showed cellulolytic activity (0.54±0.05 filter paper units mL(-1)) at 37°C. The isolate was found to hydrolyze carboxymethyl cellulose, filter paper and maize (Zea mays) straw. The maize straw digestion was confirmed by scanning electron microscopy studies. The isolate was able to degrade filter paper within 96h of incubation. A full length cellulase gene of AMS6 was amplified using degenerate primers consisting of 1499 nucleotides. The ORF encoded for a protein of 499 amino acids residues with a predicted molecular mass of 55.04kDa. The amino acids sequence consisted of a glycosyl hydrolase family 5 domain at N-terminal; Glycosyl hydrolase catalytic core and a CBM-3 cellulose binding domain at its C terminal. The study suggests potential probiotic B. subtilis AMS6 as a promising candidate envisaging its application as an animal feed additive for enhanced fiber digestion and gut health of animal.

  8. [Pilot study of thermal treatment/thermophilic anaerobic digestion process treating waste activated sludge of high solid content].

    Science.gov (United States)

    Wu, Jing; Wang, Guang-qi; Cao, Zhi-ping; Li, Zhong-hua; Hu, Yu-ying; Wang, Kai-jun; Zu, Jian-e

    2014-09-01

    A pilot-scale experiment about the process of "thermal pretreatment at 70°C/thermophilic anaerobic digestion" of waste activated sludge of high solid content (8% -9% ) was conducted. The process employed thermal treatment of 3 days to accelerate the hydrolysis and thermophilic digestion to enhance anaerobic reaction. Thus it was good at organic removal and stabilization. When the solid retention time (SRT) was longer than 20 days, the VSS removal rate was greater than 42. 22% and it was linearly correlated to the SRT of the aerobic digestion with the R2 of 0. 915 3. It was suggested that SRT of anaerobic digestion was 25 days in practice. VSS removal rate and biogas production rate of the pilot experiment were similar to those of the run-well traditional full-scale sludge anaerobic digestion plants (solid content 3% -5% ) and the plant of high solid content using German technique.

  9. Efficient production of 2,3-butanediol from corn stover hydrolysate by using a thermophilic Bacillus licheniformis strain.

    Science.gov (United States)

    Li, Lixiang; Li, Kun; Wang, Kai; Chen, Chao; Gao, Chao; Ma, Cuiqing; Xu, Ping

    2014-10-01

    In this study, a thermophilic Bacillus licheniformis strain X10 was newly isolated for 2,3-butanediol (2,3-BD) production from lignocellulosic hydrolysate. Strain X10 could utilize glucose and xylose simultaneously without carbon catabolite repression. In addition, strain X10 possesses high tolerance to fermentation inhibitors including furfural, vanillin, formic acid, and acetic acid. In a fed-batch fermentation, 74.0g/L of 2,3-BD was obtained from corn stover hydrolysate, with a productivity of 2.1g/Lh and a yield of 94.6%. Thus, this thermophilic B. licheniformis strain is a candidate for the development of efficient industrial production of 2,3-BD from corn stover hydrolysate.

  10. Efficient production of 2,3-butanediol from corn stover hydrolysate by using a thermophilic Bacillus licheniformis strain.

    Science.gov (United States)

    Li, Lixiang; Li, Kun; Wang, Kai; Chen, Chao; Gao, Chao; Ma, Cuiqing; Xu, Ping

    2014-10-01

    In this study, a thermophilic Bacillus licheniformis strain X10 was newly isolated for 2,3-butanediol (2,3-BD) production from lignocellulosic hydrolysate. Strain X10 could utilize glucose and xylose simultaneously without carbon catabolite repression. In addition, strain X10 possesses high tolerance to fermentation inhibitors including furfural, vanillin, formic acid, and acetic acid. In a fed-batch fermentation, 74.0g/L of 2,3-BD was obtained from corn stover hydrolysate, with a productivity of 2.1g/Lh and a yield of 94.6%. Thus, this thermophilic B. licheniformis strain is a candidate for the development of efficient industrial production of 2,3-BD from corn stover hydrolysate. PMID:25151068

  11. Thermophilic digestion of pig manure slurries at 48 deg. C; Termofil udraadning af svinegylle ved 48 grader C

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, J.; Joergensen, P.; Hannibal, E.

    1995-06-01

    Thermophilic digestion of pig manure slurries can give problems because of its high nitrogen content that, together with high concentrations of ammonia content, can encumber the growth activities of the bacteria so that the production of methane will be stopped. A series of experiments were carried out on a biomass conversion plant located on a farm in order to address this problem. These are described and the resulting data are given. It was concluded that it is possible to solve the problem by operating at a temperature of 48 deg. C, a low thermophilic temperature. The production of methane was also increased under these conditions, to 0.53 cubic meters per kilogram organic dry matter. Methane production is also highly dependent on residence time in the reactor, which is recommended as being 16 days and nights. Bentonite can have a stabilizing effect on the ammonia-binding process. (AB)

  12. TtMCO: A highly thermostable laccase-like multicopper oxidase from the thermophilic Thermobaculum terrenum

    DEFF Research Database (Denmark)

    Brander, Søren; Mikkelsen, Jørn Dalgaard; Kepp, Kasper Planeta

    2015-01-01

    This paper reports the identification, heterologous expression in Escherichia coli and characterization of TtMCO from the thermophilic bacterium Thermobaculum terrenum, the first laccase-like multi-copper oxidase (LMCO) from the distinct Phylum Chloroflexi. TtMCO has only 39% identity to its clos...... closest characterized homologue, CotA from Bacillus subtilis, but sequence and spectrophotometry confirmed copper coordination similar to that of LMCOs. TtMCO is extremely thermophilic with a half-time of inactivation of 2.24 days at 70 degrees C and 350 min at 80°C and pH 7, consistent...... with a hyperthermal habitat of the host. TtMCO was screened for activity against 56 chemically diverse substrates. It displayed limited activity on classical LMCO substrates, such as e.g. phenolics, transition metals, or bilirubin. Highest activities were observed for nitrogen-containing aromatic compounds, i.e. 1...

  13. Increased loading rates and specific methane yields facilitated by digesting grass silage at thermophilic rather than mesophilic temperatures.

    Science.gov (United States)

    Voelklein, M A; Rusmanis, D; Murphy, J D

    2016-09-01

    This study was conducted to advance the understanding of thermophilic grass digestion. Late harvested grass silage was fermented at thermophilic conditions at increasing organic loading rates (OLR). Stable digestion took place at an OLR between 3 and 4gVSL(-1)d(-1). This enabled specific methane yields (SMY) as high as 405LCH4kgVS(-1). An accumulation of volatile fatty acids (VFA), accompanied by a gradual deterioration of pH, FOS/TAC (ratio of VFA to alkalinity) arose at an OLR between 5 and 7gVSL(-1)d(-1), yet inhibition did not occur. SMY decreased with reduced retention time ranging between 336 and 358LCH4kgVS(-1) at OLR 7 and 5gVSL(-1)d(-1) respectively. The biomethane efficiencies remained high (92-103%) at corresponding retention times. Comparative results indicated a superior performance with respect to higher loading and SMY as compared with mesophilic conditions.

  14. Mesophilic and thermophilic anaerobic digestion of primary and secondary sludge. Effect of pre-treatment at elevated temperature

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Yenal, U.; Skiadas, Ioannis V.;

    2003-01-01

    subsequent thermophilic digestion of primary sludge. The methane production rate was mostly influenced by the pre-treatment of secondary sludge followed by mesophilic and thermophilic digestion whereas the methane potential only was positively influenced when mesophilic digestion followed. Our results...... digestion. Furthermore, thermal pre-treatment is suitable for the improvement of stabilization, enhancement of dewatering of the sludge, reduction of the numbers of pathogens and could be realized at relatively low cost especially at low temperatures. The present study investigates (a) the differences...... suggest that the selection of the pre-treatment duration as well as the temperature of the subsequent anaerobic step for sludge stabilization should depend on the ratio of primary to secondary sludge....

  15. Isolation and characterization of a heavy metal-resistant, thermophilic esterase from a Red Sea Brine Pool

    KAUST Repository

    Mohamed, Yasmine M.

    2013-11-28

    The Red Sea Atlantis II brine pool is an extreme environment that displays multiple harsh conditions such as high temperature, high salinity and high concentrations of multiple, toxic heavy metals. The survival of microbes in such an environment by utilizing resistant enzymes makes them an excellent source of extremophilic enzymes. We constructed a fosmid metagenomic library using DNA isolated from the deepest and most secluded layer of this pool. We report the isolation and biochemical characterization of an unusual esterase: EstATII. EstATII is thermophilic (optimum temperature, 65 C), halotolerant (maintains its activity in up to 4.5â€...M NaCl) and maintains at least 60% of its activity in the presence of a wide spectrum of heavy metals. The combination of biochemical characteristics of the Red Sea Atlantis II brine pool esterase, i.e., halotolerance, thermophilicity and resistance to heavy metals, makes it a potentially useful biocatalyst.

  16. Prevalence, antimicrobial resistance and risk factors for thermophilic Campylobacter infections in symptomatic and asymptomatic humans in Tanzania

    DEFF Research Database (Denmark)

    Komba, E. V. G.; Mdegela, R. H.; Msoffe, P. L. M.;

    2015-01-01

    testing employed the disc diffusion method. A small proportion of the test isolates was also subjected to agar dilution method. Risk factors for human illness were determined in an unmatched case-control study. Thermophilic Campylobacter were isolated from 11.4% of the screened individuals (n = 1195). The...... sulphate and lowest for ciprofloxacin (22.1%). The rates of resistance for other antibiotics (azithromycin, erythromycin, tetracycline, cephalothin, gentamycin, nalidixic acid, ampicillin, amoxycillin, norfloxacin, chloramphenicol) ranged from 44.1% to 89%. Comparison between disc diffusion and agar...... dilution methods indicated a good correlation, and the tests were in agreement to each other (κ ≥ 0.75). Human illness was found to be associated with young age and consumption of chicken meat and pre-prepared salad. Our data indicate the presence of antibiotic-resistant thermophilic Campylobacter in...

  17. Improving the stability of thermophilic anaerobic digesters treating SS-OFMSW through enrichment with compost and leachate seeds

    KAUST Repository

    Ghanimeh, Sophia A.

    2013-03-01

    This paper examines the potential of improving the stability of thermophilic anaerobic digestion of source-sorted organic fraction of municipal solid waste (SS-OFMSW) by adding leachate and compost during inoculation. For this purpose, two stable thermophilic digesters, A (control) and B (with added leachate and compost), were subjected to a sustained substrate shock by doubling the organic loading rate for one week. Feeding was suspended then gradually resumed to reach the pre-shock loading rate (2. gVS/l/d). Digester A failed, exhibiting excessive increase in acetate and a corresponding decrease in pH and methane generation, and lower COD and solids removal efficiencies. In contrast, digester B was able to restore its functionality with 90% recovery of pre-shock methane generation rate at stable pH, lower hydrogen levels, and reduced VFAs and ammonia accumulation. © 2012 Elsevier Ltd.

  18. Toward the physical basis of thermophilic proteins: linking of enriched polar interactions and reduced heat capacity of unfolding.

    Science.gov (United States)

    Zhou, Huan-Xiang

    2002-01-01

    The enrichment of salt bridges and hydrogen bonding in thermophilic proteins has long been recognized. Another tendency, featuring lower heat capacity of unfolding (DeltaC(p)) than found in mesophilic proteins, is emerging from the recent literature. Here we present a simple electrostatic model to illustrate that formation of a salt-bridge or hydrogen-bonding network around an ionized group in the folded state leads to increased folding stability and decreased DeltaC(p). We thus suggest that the reduced DeltaC(p) of thermophilic proteins could partly be attributed to enriched polar interactions. A reduced DeltaC(p) might serve as an indicator for the contribution of polar interactions to folding stability. PMID:12496083

  19. Fermentative hydrogen production from hydrolyzed cellulosic feedstock prepared with a thermophilic anaerobic bacterial isolate

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yung Chung [Department of Chemical Engineering, National Cheng Kung University, No. 1 University Road, Tainan 701 (China); Huang, Chi-Yu.; Fu, Tzu-Ning [Department of Environmental Engineering and Science, Tunghai University, Taichung 407 (China); Chen, Chun-Yen; Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, No. 1 University Road, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China)

    2009-08-15

    Hydrogen gas was produced via dark fermentation from natural cellulosic materials and {alpha}-cellulose via a two-step process, in which the cellulosic substrates were first hydrolyzed by an isolated cellulolytic bacterium Clostridium strain TCW1, and the resulting hydrolysates were then used as substrate for fermentative H{sub 2} production. The TCW1 strain was able to hydrolyze all the cellulosic materials examined to produce reducing sugars (RS), attaining the best reducing sugar production yield of 0.65 g reducing sugar/g substrate from hydrolysis of {alpha}-cellulose. The hydrolysates of those cellulosic materials were successfully converted to H{sub 2} via dark fermentation using seven H{sub 2}-producing bacterial isolates. The bioH{sub 2} production performance was highly dependent on the type of cellulosic feedstock used, the initial reducing sugar concentration (C{sub RS,o}) (ranging from 0.7 to 4.5 mg/l), as well as the composition of sugar and soluble metabolites present in the cellulosic hydrolysates. It was found that Clostridium butyricum CGS5 displayed the highest H{sub 2}-producing efficiency with a cumulative H{sub 2} production of 270 ml/l from {alpha}-cellulose hydrolysate (C{sub RS,o} = 4.52 mg/l) and a H{sub 2} yield of 7.40 mmol/g RS (or 6.66 mmol/g substrate) from napier grass hydrolysate (C{sub RS,o} = 1.22 g/l). (author)

  20. Isolation and Characterization of Thermophilic Cellulase-Producing Bacteria from Empty Fruit Bunches-Palm Oil Mill Effluent Compost

    Directory of Open Access Journals (Sweden)

    Azhari S. Baharuddin

    2010-01-01

    Full Text Available Problems statement: Lack of information on locally isolated cellulase-producing bacterium in thermophilic compost using a mixture of Empty Fruit Bunch (EFB and Palm Oil Mill Effluent (POME as composting materials. Approach: The isolation of microbes from compost heap was conducted at day 7 of composting process where the mixture of composting materials consisted of 45.8% cellulose, 17.1% hemicellulose and 28.3% lignin content. The temperature, pH and moisture content of the composting pile at day 7 treatment were 58.3, 8.1 and 65.5°C, respectively. The morphological analysis of the isolated microbes was conducted using Scanning Electron Microscope (SEM and Gram stain method. The congo red test was conducted in order to detect 1% CMC agar degradation activities. Total genomic DNAs were extracted from approximately 1.0 g of mixed compost and amplified by using PCR primers. The PCR product was sequent to identify the nearest relatives of 16S rRNA genes. The localization of bacteria chromosomes was determined by Fluorescence In Situ Hybridization (FISH analysis. Results: Single isolated bacteria species was successfully isolated from Empty Fruit Bunch (EFB-Palm Oil Mill Effluent (POME compost at thermophilic stage. Restriction fragment length polymorphism profiles of the DNAs coding for the 16S rRNAs with the phylogenetic analysis showed that the isolated bacteria from EFB-POME thermophilic compost gave the highest homology (99% with similarity to Geobacillus pallidus. The strain was spore forming bacteria and able to grow at 60°C with pH 7. Conclusion: Thermophilic bacteria strain, Geobacillus pallidus was successfully isolated from Empty Fruit Bunch (EFB and Palm Oil Mil Effluent (POME compost and characterized.

  1. Thermophilic Anaerobic Biodegradation of [14C]Lignin, [14C]Cellulose, and [14C]Lignocellulose Preparations

    OpenAIRE

    Benner, Ronald; Hodson, Robert E.

    1985-01-01

    Thermophilic (55°C) anaerobic enrichment cultures were incubated with [14C-lignin]lignocellulose, [14C-polysaccharide]lignocellulose, and kraft [14C]lignin prepared from slash pine, Pinus elliottii, and 14C-labeled preparations of synthetic lignin and purified cellulose. Significant but low percentages (2 to 4%) of synthetic and natural pine lignin were recovered as labeled methane and carbon dioxide during 60-day incubations, whereas much greater percentages (13 to 23%) of kraft lignin were ...

  2. Hydrogen Limitation and Syntrophic Growth among Natural Assemblages of Thermophilic Methanogens at Deep-sea Hydrothermal Vents.

    Science.gov (United States)

    Topçuoğlu, Begüm D; Stewart, Lucy C; Morrison, Hilary G; Butterfield, David A; Huber, Julie A; Holden, James F

    2016-01-01

    Thermophilic methanogens are common autotrophs at hydrothermal vents, but their growth constraints and dependence on H2 syntrophy in situ are poorly understood. Between 2012 and 2015, methanogens and H2-producing heterotrophs were detected by growth at 80°C and 55°C at most diffuse (7-40°C) hydrothermal vent sites at Axial Seamount. Microcosm incubations of diffuse hydrothermal fluids at 80°C and 55°C demonstrated that growth of thermophilic and hyperthermophilic methanogens is primarily limited by H2 availability. Amendment of microcosms with NH4 (+) generally had no effect on CH4 production. However, annual variations in abundance and CH4 production were observed in relation to the eruption cycle of the seamount. Microcosm incubations of hydrothermal fluids at 80°C and 55°C supplemented with tryptone and no added H2 showed CH4 production indicating the capacity in situ for methanogenic H2 syntrophy. 16S rRNA genes were found in 80°C microcosms from H2-producing archaea and H2-consuming methanogens, but not for any bacteria. In 55°C microcosms, sequences were found from H2-producing bacteria and H2-consuming methanogens and sulfate-reducing bacteria. A co-culture of representative organisms showed that Thermococcus paralvinellae supported the syntrophic growth of Methanocaldococcus bathoardescens at 82°C and Methanothermococcus sp. strain BW11 at 60°C. The results demonstrate that modeling of subseafloor methanogenesis should focus primarily on H2 availability and temperature, and that thermophilic H2 syntrophy can support methanogenesis within natural microbial assemblages and may be an important energy source for thermophilic autotrophs in marine geothermal environments. PMID:27547206

  3. Hydrogen Limitation and Syntrophic Growth among Natural Assemblages of Thermophilic Methanogens at Deep-sea Hydrothermal Vents.

    Science.gov (United States)

    Topçuoğlu, Begüm D; Stewart, Lucy C; Morrison, Hilary G; Butterfield, David A; Huber, Julie A; Holden, James F

    2016-01-01

    Thermophilic methanogens are common autotrophs at hydrothermal vents, but their growth constraints and dependence on H2 syntrophy in situ are poorly understood. Between 2012 and 2015, methanogens and H2-producing heterotrophs were detected by growth at 80°C and 55°C at most diffuse (7-40°C) hydrothermal vent sites at Axial Seamount. Microcosm incubations of diffuse hydrothermal fluids at 80°C and 55°C demonstrated that growth of thermophilic and hyperthermophilic methanogens is primarily limited by H2 availability. Amendment of microcosms with NH4 (+) generally had no effect on CH4 production. However, annual variations in abundance and CH4 production were observed in relation to the eruption cycle of the seamount. Microcosm incubations of hydrothermal fluids at 80°C and 55°C supplemented with tryptone and no added H2 showed CH4 production indicating the capacity in situ for methanogenic H2 syntrophy. 16S rRNA genes were found in 80°C microcosms from H2-producing archaea and H2-consuming methanogens, but not for any bacteria. In 55°C microcosms, sequences were found from H2-producing bacteria and H2-consuming methanogens and sulfate-reducing bacteria. A co-culture of representative organisms showed that Thermococcus paralvinellae supported the syntrophic growth of Methanocaldococcus bathoardescens at 82°C and Methanothermococcus sp. strain BW11 at 60°C. The results demonstrate that modeling of subseafloor methanogenesis should focus primarily on H2 availability and temperature, and that thermophilic H2 syntrophy can support methanogenesis within natural microbial assemblages and may be an important energy source for thermophilic autotrophs in marine geothermal environments.

  4. Hydrogen Limitation and Syntrophic Growth among Natural Assemblages of Thermophilic Methanogens at Deep-sea Hydrothermal Vents

    Science.gov (United States)

    Topçuoğlu, Begüm D.; Stewart, Lucy C.; Morrison, Hilary G.; Butterfield, David A.; Huber, Julie A.; Holden, James F.

    2016-01-01

    Thermophilic methanogens are common autotrophs at hydrothermal vents, but their growth constraints and dependence on H2 syntrophy in situ are poorly understood. Between 2012 and 2015, methanogens and H2-producing heterotrophs were detected by growth at 80°C and 55°C at most diffuse (7–40°C) hydrothermal vent sites at Axial Seamount. Microcosm incubations of diffuse hydrothermal fluids at 80°C and 55°C demonstrated that growth of thermophilic and hyperthermophilic methanogens is primarily limited by H2 availability. Amendment of microcosms with NH4+ generally had no effect on CH4 production. However, annual variations in abundance and CH4 production were observed in relation to the eruption cycle of the seamount. Microcosm incubations of hydrothermal fluids at 80°C and 55°C supplemented with tryptone and no added H2 showed CH4 production indicating the capacity in situ for methanogenic H2 syntrophy. 16S rRNA genes were found in 80°C microcosms from H2-producing archaea and H2-consuming methanogens, but not for any bacteria. In 55°C microcosms, sequences were found from H2-producing bacteria and H2-consuming methanogens and sulfate-reducing bacteria. A co-culture of representative organisms showed that Thermococcus paralvinellae supported the syntrophic growth of Methanocaldococcus bathoardescens at 82°C and Methanothermococcus sp. strain BW11 at 60°C. The results demonstrate that modeling of subseafloor methanogenesis should focus primarily on H2 availability and temperature, and that thermophilic H2 syntrophy can support methanogenesis within natural microbial assemblages and may be an important energy source for thermophilic autotrophs in marine geothermal environments. PMID:27547206

  5. Biochemical properties of xylanases from a thermophilic fungus, Melanocarpus albomyces, and their action on plant cell walls

    OpenAIRE

    Prabhu, Ashok K; Maheshwari, Ramesh

    1999-01-01

    Melanocarpus albomyces, a thermophilic fungus isolated from compost by enrichment culture in a liquid medium containing sugarcane bagasse, produced cellulase-free xylanase in culture medium. The fungus was unusual in that xylanase activity was inducible not only by hemicellulosic material but also by the monomeric pentosan unit of xylan but not by glucose. Concentration of bagasse-grown culture filtrate protein followed by size-exclusion and anion-exchange chromatography separated four xylana...

  6. Progressive Degradation of Crude Oil n-Alkanes Coupled to Methane Production under Mesophilic and Thermophilic Conditions

    OpenAIRE

    Cheng, Lei; Shi, Shengbao; Li, Qiang; Chen, Jianfa; Hui ZHANG; Lu, Yahai

    2014-01-01

    Although methanogenic degradation of hydrocarbons has become a well-known process, little is known about which crude oil tend to be degraded at different temperatures and how the microbial community is responded. In this study, we assessed the methanogenic crude oil degradation capacity of oily sludge microbes enriched from the Shengli oilfield under mesophilic and thermophilic conditions. The microbial communities were investigated by terminal restriction fragment length polymorphism (T-RFLP...

  7. Deep Conversion of Carbon Monoxide to Hydrogen and Formation of Acetate by the Anaerobic Thermophile Carboxydothermus hydrogenoformans

    OpenAIRE

    Henstra, Anne M.; Stams, Alfons J. M.

    2011-01-01

    Carboxydothermus hydrogenoformans is a thermophilic strictly anaerobic bacterium that catalyses the water gas shift reaction, the conversion of carbon monoxide with water to molecular hydrogen and carbon dioxide. The thermodynamically favorable growth temperature, compared to existing industrial catalytic processes, makes this organism an interesting alternative for production of cheap hydrogen gas suitable to fuel CO-sensitive fuel cells in a future hydrogen economy, provided sufficiently lo...

  8. Evaluation of methods for preparing hydrogen-producing seed inocula under thermophilic condition by process performance and microbial community analysis.

    Science.gov (United States)

    O-Thong, Sompong; Prasertsan, Poonsuk; Birkeland, Nils-Kåre

    2009-01-01

    Five methods for preparation of hydrogen-producing seeds (base, acid, 2-bromoethanesulfonic acid (BESA), load-shock and heat shock treatments) as well as an untreated anaerobic digested sludge were compared for their hydrogen production performance and responsible microbial community structures under thermophilic condition (60 degrees C). The results showed that the load-shock treatment method was the best for enriching thermophilic hydrogen-producing seeds from mixed anaerobic cultures as it completely repressed methanogenic activity and gave the a maximum hydrogen production yield of 1.96 mol H(2) mol(-1) hexose with an hydrogen production rate of 11.2 mmol H(2) l(-1)h(-1). Load-shock and heat-shock treatments resulted in a dominance of Thermoanaerobacterium thermosaccharolyticum with acetic acid and butyric acid type of fermentation while base- and acid-treated seeds were dominated by Clostridium sp. and BESA-treated seeds were dominated by Bacillus sp. The comparative experimental results from hydrogen production performance and microbial community analysis showed that the load-shock treatment method was better than the other four methods for enriching thermophilic hydrogen-producing seeds from anaerobic digested sludge. Load-shock treated sludge was implemented in palm oil mill effluent (POME) fermentation and was found to give maximum hydrogen production rates of 13.34 mmol H(2) l(-1)h(-1) and resulted in a dominance of Thermoanaerobacterium spp. Load-shock treatment is an easy and practical method for enriching thermophilic hydrogen-producing bacteria from anaerobic digested sludge.

  9. Acid-Tolerant Moderately Thermophilic Methanotrophs of the Class Gammaproteobacteria Isolated From Tropical Topsoil with Methane Seeps

    OpenAIRE

    Islam, Tajul; Torsvik, Vigdis; Larsen, Øivind; Bodrossy, Levente; Øvreås, Lise; Birkeland, Nils-Kåre

    2016-01-01

    Terrestrial tropical methane seep habitats are important ecosystems in the methane cycle. Methane oxidizing bacteria play a key role in these ecosystems as they reduce methane emissions to the atmosphere. Here, we describe the isolation and initial characterization of two novel moderately thermophilic and acid-tolerant obligate methanotrophs, assigned BFH1 and BFH2 recovered from a tropical methane seep topsoil habitat. The new isolates were strictly aerobic, non-motile, coccus-shaped and uti...

  10. Crystallization and preliminary X-ray crystallographic analysis of L-arabinose isomerase from thermophilic Geobacillus kaustophilus.

    Science.gov (United States)

    Cao, Thinh-Phat; Choi, Jin Myung; Lee, Sang-Jae; Lee, Yong-Jik; Lee, Sung-Keun; Jun, Youngsoo; Lee, Dong-Woo; Lee, Sung Haeng

    2014-01-01

    L-arabinose isomerase (AI), which catalyzes the isomerization of L-arabinose to L-ribulose, can also convert D-galactose to D-tagatose, a natural sugar replacer, which is of commercial interest in the food and healthcare industries. Intriguingly, mesophilic and thermophilic AIs showed different substrate preferences and metal requirements in catalysis and different thermostabilities. However, the catalytic mechanism of thermophilic AIs still remains unclear. Therefore, thermophilic Geobacillus kaustophilus AI (GKAI) was overexpressed, purified and crystallized, and a preliminary X-ray diffraction data set was obtained. Diffraction data were collected from a GKAI crystal to 2.70 Å resolution. The crystal belonged to the monoclinic space group C2, with unit-cell parameters a = 224.12, b = 152.95, c = 91.28 Å, β = 103.61°. The asymmetric unit contained six molecules, with a calculated Matthews coefficient of 2.25 Å(3) Da(-1) and a solvent content of 45.39%. The three-dimensional structure determination of GKAI is currently in progress by molecular replacement and model building.

  11. A Novel Process Configuration for Anaerobic Digestion of Source-Sorted Household Waste Using Hyper-Thermophilic Post-Treatment

    DEFF Research Database (Denmark)

    Hartmann, H.; Ahring, Birgitte Kiær

    2005-01-01

    A novel reactor configuration was investigated for anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW). An anaerobic hyper-thermophilic (68°C) reactor R68 was implemented as a post–treatment step for the effluent of a thermophilic reactor R1 (55°C) in order to enhance...... hydrolysis of recalcitrant organic matter, improve sanitation and ease the stripping of ammonia from the reactor. The efficiency of the combined system was studied in terms of methane yield, volatile solids (VS) reduction and volatile fatty acid (VFA) production at different hydraulic retention times (HRT......). A single-stage thermophilic (55°C) reactor R2 was used as control. VS reduction and biogas yield of the combined system was 78 – 89% and 640 – 790 ml/g-VS, respectively. While the VS reduction in the combined system was up to 7% higher than in the single-stage treatment, no increase in methane yield...

  12. Mesophilic and thermophilic anaerobic digestion of the liquid fraction of pressed biowaste for high energy yields recovery.

    Science.gov (United States)

    Micolucci, Federico; Gottardo, Marco; Cavinato, Cristina; Pavan, Paolo; Bolzonella, David

    2016-02-01

    Deep separate collection of the organic fraction of municipal solid waste generates streams with relatively low content of inert material and high biodegradability. This material can be conveniently treated to recovery both energy and material by means of simplified technologies like screw-press and extruder: in this study, the liquid fraction generated from pressed biowaste from kerbside and door-to-door collection was anaerobically digested in both mesophilic and thermophilic conditions while for the solid fraction composting is suggested. Continuous operation results obtained both in mesophilic and thermophilic conditions indicated that the anaerobic digestion of pressed biowaste was viable at all operating conditions tested, with the greatest specific gas production of 0.92m(3)/kgVSfed at an organic loading rate of 4.7kgVS/m(3)d in thermophilic conditions. Based on calculations the authors found that the expected energy recovery is highly positive. The contents of heavy metals and pathogens of fed substrate and effluent digestates were analyzed, and results showed low levels (below End-of-Waste 2014 criteria limits) for both the parameters thus indicating the good quality of digestate and its possible use for agronomic purposes. Therefore, both energy and material were effectively recovered. PMID:26427935

  13. Thermophilic sludge digestion improves energy balance and nutrient recovery potential in full-scale municipal wastewater treatment plants.

    Science.gov (United States)

    De Vrieze, Jo; Smet, Davey; Klok, Jacob; Colsen, Joop; Angenent, Largus T; Vlaeminck, Siegfried E

    2016-10-01

    The conventional treatment of municipal wastewater by means of activated sludge is typically energy demanding. Here, the potential benefits of: (1) the optimization of mesophilic digestion; and (2) transitioning to thermophilic sludge digestion in three wastewater treatment plants (Tilburg-Noord, Land van Cuijk and Bath) in the Netherlands is evaluated, including a full-scale trial validation in Bath. In Tilburg-Noord, thermophilic sludge digestion covered the energy requirements of the plant (102%), whereas 111% of sludge operational treatment costs could be covered in Bath. Thermophilic sludge digestion also resulted in a strong increase in nutrient release. The potential for nutrient recovery was evaluated via: (1) stripping/absorption of ammonium; (2) autotrophic removal of ammonium via partial nitritation/anammox; and (3) struvite precipitation. This research shows that optimization of sludge digestion may lead to a strong increase in energy recovery, sludge treatment costs reduction, and the potential for advanced nutrient management in full-scale sewage treatment plants. PMID:27423372

  14. Biogas Upgrading via Hydrogenotrophic Methanogenesis in Two-Stage Continuous Stirred Tank Reactors at Mesophilic and Thermophilic Conditions.

    Science.gov (United States)

    Bassani, Ilaria; Kougias, Panagiotis G; Treu, Laura; Angelidaki, Irini

    2015-10-20

    This study proposes an innovative setup composed by two stage reactors to achieve biogas upgrading coupling the CO2 in the biogas with external H2 and subsequent conversion into CH4 by hydrogenotrophic methanogenesis. In this configuration, the biogas produced in the first reactor was transferred to the second one, where H2 was injected. This configuration was tested at both mesophilic and thermophilic conditions. After H2 addition, the produced biogas was upgraded to average CH4 content of 89% in the mesophilic reactor and 85% in the thermophilic. At thermophilic conditions, a higher efficiency of CH4 production and CO2 conversion was recorded. The consequent increase of pH did not inhibit the process indicating adaptation of microorganisms to higher pH levels. The effects of H2 on the microbial community were studied using high-throughput Illumina random sequences and full-length 16S rRNA genes extracted from the total sequences. The relative abundance of archaeal community markedly increased upon H2 addition with Methanoculleus as dominant genus. The increase of hydrogenotrophic methanogens and syntrophic Desulfovibrio and the decrease of aceticlastic methanogens indicate a H2-mediated shift toward the hydrogenotrophic pathway enhancing biogas upgrading. Moreover, Thermoanaerobacteraceae were likely involved in syntrophic acetate oxidation with hydrogenotrophic methanogens in absence of aceticlastic methanogenesis.

  15. Continuous live cell imaging of cellulose attachment by microbes under anaerobic and thermophilic conditions using confocal microscopy

    Institute of Scientific and Technical Information of China (English)

    Zhi-Wu Wang; Seung-Hwan Lee; James G.Elkins; Yongchao Li; Scott Hamilton-Brehm; Jennifer L.Morrell-Falvey

    2013-01-01

    Live cell imaging methods provide important insights into the dynamics of cellular processes that cannot be derived easily from population-averaged datasets.In the bioenergy field,much research is focused on fermentation of cellulosic biomass by thermophilic microbes to produce biofuels; however,little effort is dedicated to the development of imaging tools to monitor this dynamic biological process.This is,in part,due to the experimental challenges of imaging ceils under both anaerobic and thermophilic conditions.Here an imaging system is described that integrates confocal microscopy,a flow cell device,and a lipophilic dye to visualize cells.Solutions to technical obstacles regarding suitable fluorescent markers,photodamage during imaging,and maintenance of environmental conditions during imaging are presented.This system was utilized to observe cellulose colonization by Clostridium thermocellum under anaerobic conditions at 60℃.This method enables live cell imaging of bacterial growth under anaerobic and thermophilic conditions and should be widely applicable to visualizing different cell types or processes in real time.

  16. ESTIMATION OF EXTRACELLULAR LIPOLYTIC ENZYME ACTIVITY BY THERMOPHILIC BACILLUS SP. ISOLATED FROM ARID AND SEMI-ARID REGION OF RAJASTHAN, INDIA

    Directory of Open Access Journals (Sweden)

    Deeksha Gaur

    2012-10-01

    Full Text Available Thermophilic organisms can be defined as, micro-organisms which are adapted to survive at high temperatures. The enzymes secreted by thermophilic bacteria are capable of catalyzing biochemical reactions at high temperatures. Thermophilic bacteria are able to produce thermostable lipolytic enzymes (capable of degradation of lipid at temperatures higher than mesophilic bacteria. Therefore, the isolation of thermophilic bacteria from natural sources and their identification are quite beneficial in terms of discovering thermostable lipase enzymes. Due to great temperature fluctuation in hot arid and semi-arid region of Rajasthan, this area could serve as a good source for new thermophilic lipase producing bacteria with novel industrially important properties. The main objective of this research is the isolation and estimation of industrially important thermophilic lipase enzyme produced by thermophilic bacteria, isolated from arid and semi-arid region of Rajasthan. For this research purpose soil samples were collected from Churu, Sikar and Jhunjunu regions of Rajasthan. Total 16 bacterial strains were isolated and among only 2 thermostable lipolytic enzyme producing bacteria were charcterized. The thermostable lipolytic enzyme was estimated by qualitative and quantitative experiments. The isolates were identified as Bacillus sp. by microscopic, biochemical and molecular characterization. The optimum enzyme activity was observed at pH 8, temperature 60°C and 6% salt concentrations at 24 hrs time duration. Lipolytic enzyme find useful in a variety of biotechnological fields such as food and dairy (cheese ripening, flavour development, detergent, pharmaceutical (naproxen, ibuprofen, agrochemical (insecticide, pesticide and oleochemical (fat and oil hydrolysis, biosurfactant synthesis industries. Lipolytic enzyme can be further used in many newer areas where they can serve as potential biocatalysts.

  17. A rigidifying salt-bridge favors the activity of thermophilic enzyme at high temperatures at the expense of low-temperature activity.

    Directory of Open Access Journals (Sweden)

    Sonia Y Lam

    2011-03-01

    Full Text Available BACKGROUND: Thermophilic enzymes are often less active than their mesophilic homologues at low temperatures. One hypothesis to explain this observation is that the extra stabilizing interactions increase the rigidity of thermophilic enzymes and hence reduce their activity. Here we employed a thermophilic acylphosphatase from Pyrococcus horikoshii and its homologous mesophilic acylphosphatase from human as a model to study how local rigidity of an active-site residue affects the enzymatic activity. METHODS AND FINDINGS: Acylphosphatases have a unique structural feature that its conserved active-site arginine residue forms a salt-bridge with the C-terminal carboxyl group only in thermophilic acylphosphatases, but not in mesophilic acylphosphatases. We perturbed the local rigidity of this active-site residue by removing the salt-bridge in the thermophilic acylphosphatase and by introducing the salt-bridge in the mesophilic homologue. The mutagenesis design was confirmed by x-ray crystallography. Removing the salt-bridge in the thermophilic enzyme lowered the activation energy that decreased the activation enthalpy and entropy. Conversely, the introduction of the salt-bridge to the mesophilic homologue increased the activation energy and resulted in increases in both activation enthalpy and entropy. Revealed by molecular dynamics simulations, the unrestrained arginine residue can populate more rotamer conformations, and the loss of this conformational freedom upon the formation of transition state justified the observed reduction in activation entropy. CONCLUSIONS: Our results support the conclusion that restricting the active-site flexibility entropically favors the enzymatic activity at high temperatures. However, the accompanying enthalpy-entropy compensation leads to a stronger temperature-dependency of the enzymatic activity, which explains the less active nature of the thermophilic enzymes at low temperatures.

  18. High rate mesophilic, thermophilic, and temperature phased anaerobic digestion of waste activated sludge: A pilot scale study

    International Nuclear Information System (INIS)

    Highlights: ► High temperatures were tested in single and two-stage anaerobic digestion of waste activated sludge. ► The increased temperature demonstrated the possibility of improving typical yields of the conventional mesophilic process. ► The temperature phased anaerobic digestion process (65 + 55 °C) showed the best performances with yields of 0.49 m3/kgVSfed. ► Ammonia and phosphate released from solids destruction determined the precipitation of struvite in the reactor. - Abstract: The paper reports the findings of a two-year pilot scale experimental trial for the mesophilic (35 °C), thermophilic (55 °C) and temperature phased (65 + 55 °C) anaerobic digestion of waste activated sludge. During the mesophilic and thermophilic runs, the reactor operated at an organic loading rate of 2.2 kgVS/m3d and a hydraulic retention time of 20 days. In the temperature phased run, the first reactor operated at an organic loading rate of 15 kgVS/m3d and a hydraulic retention time of 2 days while the second reactor operated at an organic loading rate of 2.2 kgVS/m3d and a hydraulic retention time of 18 days (20 days for the whole temperature phased system). The performance of the reactor improved with increases in temperature. The COD removal increased from 35% in mesophilic conditions, to 45% in thermophilic conditions, and 55% in the two stage temperature phased system. As a consequence, the specific biogas production increased from 0.33 to 0.45 and to 0.49 m3/kgVSfed at 35, 55, and 65 + 55 °C, respectively. The extreme thermophilic reactor working at 65 °C showed a high hydrolytic capability and a specific yield of 0.33 gCOD (soluble) per gVSfed. The effluent of the extreme thermophilic reactor showed an average concentration of soluble COD and volatile fatty acids of 20 and 9 g/l, respectively. Acetic and propionic acids were the main compounds found in the acids mixture. Because of the improved digestion efficiency, organic nitrogen and phosphorus were

  19. Thermophilic nitrate-reducing microorganisms prevent sulfate reduction in cold marine sediments incubated at high temperature

    Science.gov (United States)

    Nepomnyashchaya, Yana; Rezende, Julia; Hubert, Casey

    2014-05-01

    Hydrogen sulphide produced during metabolism of sulphate-reducing microorganisms (SRM) is toxic, corrosive and causes detrimental oil reservoir souring. During secondary oil recovery, injecting oil reservoirs with seawater that is rich in sulphate and that also cools high temperature formations provides favourable growth conditions for SRM. Nitrate addition can prevent metabolism of SRM by stimulating nitrate-reducing microorganisms (NRM). The investigations of thermophilic NRM are needed to develop mechanisms to control the metabolism of SRM in high temperature oil field ecosystems. We therefore established a model system consisting of enrichment cultures of cold surface marine sediments from the Baltic Sea (Aarhus Bay) that were incubated at 60°C. Enrichments contained 25 mM nitrate and 40 mM sulphate as potential electron acceptors, and a mixture of the organic substrates acetate, lactate, propionate, butyrate (5 mM each) and yeast extract (0.01%) as potential carbon sources and electron donors. Slurries were incubated at 60°C both with and without initial pasteurization at 80°C for 2 hours. In the enrichments containing both nitrate and sulphate, the concentration of nitrate decreased indicating metabolic activity of NRM. After a four-hour lag phase the rate of nitrate reduction increased and the concentration of nitrate dropped to zero after 10 hours of incubation. The concentration of nitrite increased as the reduction of nitrate progressed and reached 16.3 mM after 12 hours, before being consumed and falling to 4.4 mM after 19-day of incubation. No evidence for sulphate reduction was observed in these cultures during the 19-day incubation period. In contrast, the concentration of sulphate decreased up to 50% after one week incubation in controls containing only sulphate but no nitrate. Similar sulfate reduction rates were seen in the pasteurized controls suggesting the presence of heat resistant SRM, whereas nitrate reduction rates were lower in the

  20. Complete Genome Sequence of Herbinix luporum SD1D, a New Cellulose-Degrading Bacterium Isolated from a Thermophilic Biogas Reactor

    Science.gov (United States)

    Koeck, Daniela E.; Maus, Irena; Wibberg, Daniel; Winkler, Anika; Zverlov, Vladimir V.; Liebl, Wolfgang; Pühler, Alfred; Schwarz, Wolfgang H.

    2016-01-01

    A novel cellulolytic bacterial strain was isolated from an industrial-scale biogas plant. The 16S rRNA gene sequence of the strain SD1D showed 96.4% similarity to Herbinix hemicellulosilytica T3/55T, indicating a novel species within the genus Herbinix (family Lachnospiraceae). Here, the complete genome sequence of Herbinix luporum SD1D is reported. PMID:27445379