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1.
Microorganisms ; 12(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38399752

RESUMO

Streptococcus thermophilus is widely used as a starter culture in the dairy industry and has garnered attention as a beneficial bacterium owing to its health-promoting functionalities in humans. In this study, the probiotic potential of S. thermophilus MCC0200 isolated from a dairy product was investigated through a combinatorial approach of in vitro and in silico studies. MCC0200 demonstrated the ability to survive harsh gastrointestinal (GI) transit, adhere to intestinal mucosa and exert health-promoting traits in in vitro studies. These findings were corroborated with in silico evidence, wherein, MCC0200 genome harboured genes associated with tolerance to GI conditions, intestinal adhesion and colonization. Genome mapping also highlighted the ability of MCC0200 to produce compounds advantageous for the host (folate, bacteriocins), to release antioxidant enzymes that can quench the free radicals (superoxide dismutase, NADH peroxidase), and to metabolize food components that can be harmful to sensitive people (lactose). MCC0200 also demonstrated a positive effect on reducing cholesterol levels, proving to be a potential candidate for food and pharmaceutical applications. The absence of transmissible antibiotic resistance genes and virulence genes underscored the generally regarded as safe (GRAS) nature of MCC0200. This study explored the potential of Streptococcus thermophilus for its probable applications as a probiotic beyond the dairy industry.

2.
Arch Microbiol ; 205(10): 332, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37707605

RESUMO

Mesophilic and thermophilic methanogens belonging to the hydrogenotrophic, methylotrophic, and acetotrophic groups were isolated from Indian hot spring environments using BY and BCYT growth media. Following initial Hinf I-based PCR-RFLP screening, 70 methanogens were sequenced to ascertain their identity. These methanogens were phylogenetically and physiologically diverse and represented different taxa distributed across three physiological groups, i.e., hydrogenotrophs (53), methylotrophs (14) and acetotrophs (3). Overall, methanogens representing three families, five genera, and ten species, including two putative novel species, were recognized. The highest number and diversity of methanogens was observed at 40 â„ƒ, dominated by Methanobacterium (10; 3 species), Methanosarcina (9; 3 species), Methanothermobacter (7; 2 species), Methanomethylovorans (5; 1 species) and Methanoculleus (3; 1 species). Both putative novel methanogen species were isolated at 40 â„ƒ and belonged to the genera Methanosarcina and Methanobacterium. At 55 â„ƒ, limited diversity was observed, and resulted in the isolation of only two genera of methanogens, i.e., Methanothermobacter (28; 2 species) and Methanosarcina (4; 1 species). At 70 â„ƒ, only members of the genus Methanothermobacter (5; 2 species) were isolated, whereas no methanogen could be cultured at 85 â„ƒ. Ours is the first study that documents the extensive range of cultivable methanogenic archaea inhabiting hot springs across various geothermal provinces of India.


Assuntos
Euryarchaeota , Fontes Termais , Humanos , Archaea/genética , Meios de Cultura , Índia
3.
Anaerobe ; 83: 102780, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37619766

RESUMO

OBJECTIVE: Characterization and documentation of strain MCM B-1480T, a novel sulfate-reducing bacterium isolated from produced water of India's western offshore hydrocarbon reservoir. METHOD: Strain MCM B-1480T was unequivocally identified using a polyphasic approach routinely followed in bacterial systematics. The morphological and biochemical characterization of strain MCM B-1480T was carried out using standard microbiological techniques. RESULTS: MCM B-1480T was a Gram-stain-negative, motile, non-spore-forming, curved-rod-shaped bacterium. MCM B-1480T could grow at temperatures between 20 and 60 °C (optimum 37 °C), pH 6-8 (optimum 7), and required 1-6% NaCl (optimum 3%) for growth. Strain MCM B-1480T was reducing sulfate to produce hydrogen sulfide during growth. This strain used lactate and pyruvate as prominent electron donors, whereas sulfate, sulfite, thiosulfate, and nitrate served as electron acceptors. MCM B-1480T shared maximum 16S rRNA gene sequence homology of 98.65% with the members of the genus Pseudodesulfovibrio. The G + C content of the 3.87 Mb MCM B-1480T genome was 60.39%. Digital DDH (27.7%) and average nucleotide identity (ANI 84%) with the closest phylogenetic affiliate (less than 70% and 95%, respectively) reaffirmed its distinctiveness. The major cellular fatty acids components, namely iso-C15:0, anteiso-C15:0, C16:0, and anteiso-C17:0, differentiated strain MCM B-1480T from other species of Pseudodesulfovibrio. Genome annotation revealed the presence of genes encoding dissimilatory sulfate reduction and nitrate reduction in strain MCM B-1480T. CONCLUSION: The polyphasic studies, including SSU rRNA gene sequencing, average nucleotide identity, Digital DNA-DNA hybridization, cell wall fatty acids analysis, etc., identified strain MCM B-1480T as a novel taxon and Pseudodesulfovibrio thermohalotolerans sp. nov. was proposed (= JCM 39269T = MCC 4711T).


Assuntos
Nitratos , Sulfatos , RNA Ribossômico 16S/genética , Filogenia , Anaerobiose , Bactérias/genética , Ácidos Graxos , Hidrocarbonetos , Nucleotídeos , DNA , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana
4.
Arch Microbiol ; 205(9): 305, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37572166

RESUMO

An obligately anaerobic bacterium XHS1971T, capable of degrading cellulose and xylan, was isolated from a sediment sample of Aravali hot spring, Ratnagiri, India. Cells of strain XHS1971T were Gram-stain-negative, spore-forming, motile, long-rods. Growth was observed at temperatures 30-50 °C (optimum 40-45 °C), pH 5.0-10.0 (optimum pH 8.0) and NaCl concentrations 0-0.5% (optimum 0%). Generation time of strain XHS1971T was 5 h under optimised growth conditions. Strain XHS1971T showed the ability to metabolise different complex and simple sugars constituting lignocellulosic biomass. Glucose was fermented majorly into hydrogen, formic acid, acetic acid, and ethanol, whereas carbon dioxide, butyric acid, lactic acid and succinic acid were produced in traces. 16S rRNA gene analysis of strain XHS1971T revealed < 94.5% homology with Cellulosilyticum lentocellum DSM5427T followed by Cellulosilyticum ruminicola JCM14822T, identifying strain as a distinct member of family Lachnospiraceae. The major cellular fatty acids (> 5%) were C14:0, C16:0, C18:0, and C16:1 ω7c. The genome size of the strain was 3.74 Mb with 35.3 mol% G + C content, and genes were annotated to carbohydrate metabolism, including genes involved in the degradation of cellulose and xylan and the production of hydrogen, ethanol and acetate. The uniqueness of strain was further validated by digital DNA-DNA hybridisation (dDDH), Average Nucleotide Identity (ANI), and Average Amino Acid Identity (AAI) values of 22%, 80%, and 63%, respectively, with nearest phylogenetic affiliates. Based on the detailed analyses, we propose a new genus and species, Sporanaerobium hydrogeniformans gen. nov., sp. nov., for strain XHS1971T (= MCC3498T = KCTC15729T = JCM32657T) within family Lachnospiraceae.


Assuntos
Fontes Termais , Fontes Termais/microbiologia , Anaerobiose , Filogenia , Composição de Bases , RNA Ribossômico 16S/genética , Hidrogênio/metabolismo , Xilanos , Análise de Sequência de DNA , Bactérias Anaeróbias/genética , Ácidos Graxos/análise , Celulose/metabolismo , Etanol , DNA , DNA Bacteriano/genética , DNA Bacteriano/química , Técnicas de Tipagem Bacteriana
5.
Arch Microbiol ; 205(1): 9, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459234

RESUMO

An obligately anaerobic, rod-shaped, Gram-stain-positive, non-spore-forming, non-motile bacterial strain; designated as CtC72T was isolated from the rumen of cattle. The 16S rRNA gene sequence similarity of less than 98.65% revealed the strain as a member of the genus Actinomyces, nearest to but distinct from Actinomyces qiguomingii DSM 106201T, Actinomyces ruminicola DSM 27982T, Actinomyces procaprae JCM 33484T, Actinomyces succiniciruminis TISTR 2317, Actinomyces glycerinitolerans TISTR 2318. The low values of digital DNA-DNA hybridization (< 70%) and average nucleotide identity (< 95%) further highlighted the distinctive nature of strain CtC72T from its closest relatives. The strain CtC72T could grow at temperatures between 30 and 50 °C (optimum 40 °C), pH between 6.0 and 9.0 (optimum 7.5-8.0), and NaCl between 0 and 1.5% (optimum 0%). The strain hydrolysed cellulose and xylan and utilised a range of mono-, di-, and oligo-saccharides as a source of carbon and energy. Glucose fermentation resulted in acetic acid and formic acid as major metabolic products, while propionic acid, lactic acid, and ethanol as minor products along with CO2 production. The DNA G + C content of strain CtC72T was 68.40 (mol%, Tm) and 68.05 (%, digital). Major cellular fatty acids (> 10%) were C16:0, C18:1 ω9c, and C18:1 ω9c DMA. Based on these data, we propose that strain CtC72T be classified as a novel species, Actinomyces ruminis sp. nov., under the genus Actinomyces. The type strain is CtC72T (= KCTC 15726T = JCM 32641T = MCC 3500T).


Assuntos
Bactérias Anaeróbias , Rúmen , Bovinos , Animais , RNA Ribossômico 16S/genética , Anaerobiose , Composição de Bases , Filogenia , Análise de Sequência de DNA , Actinomyces/genética
6.
Genomics ; 114(2): 110281, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35124176

RESUMO

One cellulose-degrading strain CB08 and two xylan-degrading strains XB500-5 and X503 were isolated from buffalo rumen. All the strains were designated as putative novel species of Butyrivibrio based on phylogeny, phylogenomy, digital DNA-DNA hybridization, and average nucleotide identity with their closest type strains. The draft genome length of CB08 was ~3.54 Mb, while X503 and XB500-5 genome sizes were ~3.24 Mb and ~3.27 Mb, respectively. Only 68.28% of total orthologous clusters were shared among three genomes, and 40-44% of genes were identified as hypothetical proteins. The presence of genes encoding diverse carbohydrate-active enzymes (CAZymes) exhibited the lignocellulolytic potential of these strains. Further, the genome annotations revealed the metabolic pathways for monosaccharide fermentation to acetate, butyrate, lactate, ethanol, and hydrogen. The presence of genes for chemotaxis, antibiotic resistance, antimicrobial activity, synthesis of vitamins, and essential fatty acid suggested the versatile metabolic nature of these Butyrivibrio strains in the rumen environment.


Assuntos
Butyrivibrio , Rúmen , Animais , Butyrivibrio/genética , Butyrivibrio/metabolismo , DNA/metabolismo , Ecossistema , Genômica , Filogenia
7.
Antonie Van Leeuwenhoek ; 115(1): 19-31, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34734348

RESUMO

Laboratory evaluation of hyperthermophiles with the potential for Enhanced Oil Recovery (EOR) is often hampered by the difficulties in replicating the in situ growth conditions in the laboratory. In the present investigation, genome analysis was used to gain insights into the metabolic potential of a hyperthermophile to mobilize the residual oil from depleting high-temperature oil reservoirs. Here, we report the 1.9 Mb draft genome sequence of a hyperthermophilic anaerobic archaeon, Thermococcus sp. 101C5, with a GC content of 44%, isolated from a high-temperature oil reservoir of Gujarat, India. 101C5 possessed the genetic arsenal required for adaptation to harsh oil reservoir conditions, such as various heat shock proteins for thermo-adaptation, Trk potassium uptake system proteins for osmo-adaptation, and superoxide reductases against oxidative stress. Microbial Enhanced Oil Recovery (MEOR) potential of the strain was established by ascertaining the presence of genes encoding enzymes involved in the production of the metabolites such as hydrogen, bio-emulsifier, acetate, exopolysaccharide, etc. Production of these metabolites which pressurize the reservoir, emulsify the crude oil, lower the viscosity and reduce the drag, thus facilitating mobilization of the residual oil was experimentally confirmed. Also, the presence of crude oil degradative genes highlighted the ability of the strain to mobilize heavy residual oil, which was confirmed under simulated conditions in sand-pack studies. The obtained results demonstrated additional oil recoveries of 42.1% and 56.5% at 96 °C and 101 °C, respectively, by the strain 101C5, illustrating its potential for application in high-temperature oil reservoirs. To our best knowledge, this is the first report of genome analysis of any microbe assessed for its suitability for MEOR from the high-temperature oil reservoir.


Assuntos
Petróleo , Thermococcus , Genômica , Laboratórios , Campos de Petróleo e Gás , Thermococcus/genética
8.
Mar Genomics ; 59: 100864, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33810993

RESUMO

Methanosarcina sp. strain MSH10X1, a psychrotrophic methanogen, was isolated from sub-seafloor methane hydrate deposits of Krishna Godavari Basin on India's east coast. The strain could grow from 5 to 40 °C following all three i.e. methylotrophic, acetoclastic, and hydrogenotrophic modes of methanogenesis utilizing different substrates like methanol, trimethylamine, H2/CO2 (80/20), acetate, valerate, isobutyrate, isopropanol, and isobutanol. The genome sequencing and analysis of this strain revealed a circular chromosome of 3,557,383 bp length having 42.47 mol% G + C content, which consisted of 3110 coding genes, 58 tRNA genes, and 3 rRNA operons. The KEGG analysis highlighted the presence of genes responsible for all three modes of methanogenesis. The presence of genes like mtaB, mtaC, and mttB in the genome provided evidence for possible adaptation of strain MSH10X1 in the deep sea's low-temperature conditions.


Assuntos
Metano , Methanosarcina , Acetatos , Composição de Bases , Metanol , Methanosarcina/genética , Filogenia , RNA Ribossômico 16S
9.
Antonie Van Leeuwenhoek ; 114(2): 129-136, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33394210

RESUMO

A novel Gram-stain-positive, aerobic, non-spore-forming, and rod-shaped bacterium designated as PW21was isolated from produced water sampled from an oil reservoir in Limbodara, Gujarat, India. Growth occurred at 30-45 °C (optimum 37 °C), at pH 6.5-9.5 (optimum pH 8.5) and in the presence of 0.5-5.0% (w/v) NaCl [optimum, 3% (w/v)]. Phylogenetic analysis based on the 16S rRNA gene sequences showed that PW21T belonged to the class Actinobacteria, order Actinomycetales, family Promicromonosporaceae, and genus Xylanimonas, with the highest sequence similarity to Isoptericola cucumis AP38 (97.95% with 98.8% completeness), followed by Xylanimonas pachnodae NBRC 107,786T (97.82%) and Xylanimonas allomyrinae 2JSPR-7T(97.75%) with 100% completeness for the mentioned strains of Xylanimonas. The genome size of PW21T was 3.4 Mbp with a G+C content of 73.0 mol% (draft genome sequence). The average nucleotide identity (ANI) value of the draft genomes between PW21T and related species were found in between 76.99 and 78.93%. Major cellular fatty acids (> 10% of total fatty acids) of PW21Twere iso-C15:0, anteiso-C15:0, and C16:0. Phylogenetic, physiological, and biochemical characterisation identified strain PW21T (= KCTC 49,338T = JCM 33,795T = MCC 3936T) as a novel species of the genus Xylanimonas, and hence, name Xylanimonas oleitrophica sp. nov. PW21T is proposed.


Assuntos
Actinomycetales , Petróleo , Actinobacteria , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos , Hidrocarbonetos , Campos de Petróleo e Gás , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Mycobiology ; 48(6): 501-511, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33312017

RESUMO

Xylophagous termites are capable of degrading lignocellulose by symbiotic gut microorganisms along with the host's indigenous enzymes. Therefore, the termite gut might be a potential niche to obtain natural yeasts with celluloytic, xylanolytic and ethanologenic traits required for bioethanol production from lignocellulosic biomass. In this study, we cultured 79 yeasts from three different termites viz. Coptotermes heimi, Odontotermes javanicus and Odontotermes obesus. After suitable screening methods, we identified 53 yeasts, which belonged to 10 genera and 16 different species of both ascomycetous and basidiomycetous yeasts. Most yeasts in the present study represent their first-ever isolation from the termite gut. Representative strains of identified yeasts were evaluated for their cellulolytic, xylanolytic, and ethanologenic abilities. None of the isolates showed cellulase activity; 22 showed xylanolytic activity, while six produced substantial quantities of ethanol. Among xylanolytic cultures, Pseudozyma hubeiensis STAG 1.7 and Hannaella pagnoccae STAG 1.14 produced 1.31 and 1.17 IU of xylanase. Among ethanologenic yeasts, the strains belonging to genera Candida and Kodamaea produced high amount of ethanol. Overall, highest ethanol level of 4.42 g/L was produced by Candida tropicalis TS32 using 1% glucose, which increased up to 22.92 g/L at 35 °C, pH 4.5 with 5% glucose. Fermentation of rice straw hydrolysate gave 8.95 g/l of ethanol with a yield of 0.42 g/g using the strain TS32. Our study highlights the gut of wood-feeding termites as a potential source of diverse yeasts that would be useful in the production of xylanase and bioethanol.

11.
Enzyme Microb Technol ; 138: 109554, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32527524

RESUMO

Overexpression of a novel hydantoinase (hyuH) from P. aeruginosa (MCM B-887) in E. coli yielded optically pure carbamoyl amino acids. The use of optically pure carbamoyl amino acids as substrates facilitates the synthesis of non-proteinogenic amino acids. The enzyme hyuH shared a maximum of 92 % homology with proven hydantoinase protein sequences from the GenBank database, highlighting its novelty. Expression of hydantoinase gene was improved by >150 % by overexpressing it as a fusion protein in specialized E. coli CODON + host cells, providing adequate machinery for effective translation of the GC-rich gene. The presence of distinct residues in the substrate binding and active site of MCM B-887 hydantoinase enzyme explained its unique and broad substrate profile desirable for industrial applications. The purified enzyme, with a specific activity of 53U/mg of protein, was optimally active at 42 °C and pH 9.0 with a requirement of 2 mM Mn2+ ions. Supplementation of 500 mM of Na-glutamate enhanced the thermostability of the enzyme by more than 200 %.


Assuntos
Amidoidrolases/metabolismo , Aminoácidos/biossíntese , Proteínas de Bactérias/metabolismo , Pseudomonas aeruginosa/enzimologia , Amidoidrolases/química , Amidoidrolases/genética , Amidoidrolases/isolamento & purificação , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Domínio Catalítico , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Manganês , Modelos Moleculares , Filogenia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Especificidade por Substrato , Temperatura
12.
Mycologia ; 112(6): 1212-1239, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32057282

RESUMO

We isolated and characterized 65 anaerobic gut fungal (AGF; Neocallimastigomycota) strains from fecal samples of five wild (W, axis deer, white-tailed deer, Boer goat, mouflon, and Nilgiri tahr), one zoo-housed (Z, zebra), and three domesticated (D,  horse, sheep, and goat) herbivores in the US states of Texas (TX) and Oklahoma (OK), Wales (WA), and the Indian states of Kerala (KE) and Haryana (HA). Phylogenetic assessment using the D1-D2 regions of the large subunit (28S) rDNA and internal transcribed spacer 1 (ITS1) identified seven monophyletic clades that are distinct from all currently recognized AGF genera. All strains displayed monocentric thalli and produced exclusively or predominantly monoflagellate zoospores, with the exception of axis deer strains, which produced polyflagellate zoospores. Analysis of amplicon-based AGF diversity surveys indicated that zebra and horse strains are representatives of uncultured AL1 group, whereas domesticated goat and sheep strains are representatives of uncultured AL5 group, previously encountered in fecal and rumen samples of multiple herbivores. The other five lineages, all of which were isolated from wild herbivores, have not been previously encountered in such surveys. Our results significantly expand the genus-level diversity within the Neocallimastigomycota and strongly suggest that wild herbivores represent a yet-untapped reservoir of AGF diversity. We propose seven novel genera and eight novel Neocallimastigomycota species to comprise these strains, for which we propose the names Agriosomyces longus (mouflon and wild Boer goat), Aklioshbomyces papillarum (white-tailed deer), Capellomyces foraminis (wild Boar goat), and C. elongatus (domesticated goat), Ghazallomyces constrictus (axis deer), Joblinomyces apicalis (domesticated goat and sheep), Khoyollomyces ramosus (zebra-horse), and Tahromyces munnarensis (Nilgiri tahr).


Assuntos
Animais Domésticos/microbiologia , Animais Selvagens/microbiologia , Animais de Zoológico/microbiologia , Herbivoria , Neocallimastigomycota/classificação , Neocallimastigomycota/genética , Filogenia , Anaerobiose , Animais , DNA Fúngico/genética , DNA Ribossômico/genética , Cervos/microbiologia , Fezes/microbiologia , Feminino , Cabras/microbiologia , Herbivoria/classificação , Cavalos/microbiologia , Masculino , Neocallimastigomycota/isolamento & purificação , Ovinos/microbiologia , Suínos/microbiologia
13.
Bioresour Technol ; 289: 121639, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31212172

RESUMO

Effects of different process and nutritional parameters on microbial community structure and function were investigated to enhance the biomethanation of rice straw without any thermochemical pre-treatment. The study was performed in a mesophilic anaerobic digester with cattle dung slurry as inoculum. The highest methane yield of 274 ml g-1 volatile solids was obtained from particulate rice straw (1 mm size, 7.5% solids loading rate) at 37 °C, pH-7, when supplemented with urea (carbon: nitrogen ratio, 25:1) and zinc as trace element (100 µM) at 21 days hydraulic retention time. The optimization of conditions selected Clostridium, Bacteroides, and Ruminococcus as dominant hydrolytic bacteria and Methanosarcina as the methanogen. Analysis of metagenome and metatranscriptome revealed wide array of bacterial lignocellulolytic enzymes that efficiently hydrolyzed the rice straw. The methane yield was >80% of the theoretical yield, making this green process a sustainable choice for efficient extraction of energy from rice straw.


Assuntos
Microbiota , Oryza , Anaerobiose , Animais , Biocombustíveis , Reatores Biológicos , Bovinos , Metano
14.
Antonie Van Leeuwenhoek ; 112(9): 1399-1408, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30968234

RESUMO

Methane oxidation by methanotrophs is a very important environmental process in the mitigation of methane. Methylobacter (Mtb.) clade 2 members have been reported as dominant methane oxidisers in soils and sediments worldwide. We enriched and purified a methanotroph from a tropical rice field soil sample from India. The highly enriched culture showed the presence of motile, long and thick rods (3-5 µm × 0.9-1.2 µm) and minor presence of short, thin rods. The culture was purified on agarose medium and formed yellow colonies which showed the presence of only thick and long rods, henceforth termed as strain KRF1. Based on 16S rRNA gene sequence analysis, strain KRF1 shows close phylogenetic affiliation to Methylobacter tundripaludum SV96T (98.6% similarity). Due to the taxonomic novelty, and being the first member of Mtb. related to Mtb. tundripaludum from the tropics, the draft genome was sequenced. From the blastx analysis of the contigs, it was clear that the culture still had contamination of another organism, a Methylophilus species. The data binned in two clear bins: Mtb. related contigs and Methylophilus-related contigs. The binned draft genome of KRF1 shows features including the typical pathways for methane metabolism, denitrification and the presence of molybdenum iron and vanadium-iron nitrogenase genes. KRF1 is phylogenetically distinct from the five strains of Mtb. tundripaludum including SV96T, Lake Washington strains and OWC strains, showing ~ 26% DDH and ~ 81% ANIb values and a unique position in a phylogenomic tree. Subsequently, KRF1 has been completely purified from its methylotrophic partner and a pure culture has been established and maintained in a WDCM approved culture collection, the MACS Collection of Microorganisms (as MCM 1471). KRF1 is thus the first cultured member of a putative novel species of Methylobacter clade 2 isolated from the tropics.


Assuntos
Methylococcaceae/classificação , Methylococcaceae/isolamento & purificação , Microbiologia do Solo , Técnicas Bacteriológicas , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Desnitrificação , Genoma Bacteriano , Índia , Redes e Vias Metabólicas/genética , Metano/metabolismo , Methylococcaceae/genética , Methylococcaceae/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Clima Tropical , Sequenciamento Completo do Genoma
15.
Bioresour Technol ; 279: 25-33, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30710817

RESUMO

Biomethanation of rice straw was performed at 55 °C without thermochemical pretreatment using cattle dung supplemented with Methanothermobacter thermautotrophicus strains. Methane yield of 323 ml g-1 VS obtained under optimized conditions such as particle size (1 mm), carbon to nitrogen ratio (15:1), substrate to inoculum ratio (1:1), organic loading rate (7.5% w/v) and hydraulic retention time (20 days), was one of the highest ever reported from rice straw. Metagenome analysis revealed several putative novel taxa among resident microbes. The genomes of Clostridium, Hungateiclostridium, Alkaliphilus, Anaerocolumna, Olsenella, Paenibacillus, Pseudoclostridium, Tepidanaerobacter and Turicibacter were recovered as metagenome assisted genomes. Clostridium spp. and M. thermautotrophicus were the dominant hydrolytic and methanogenic microbes, respectively. Syntrophic acetate oxidation coupled to hydrogenotrophic methanogenesis was found to be the major pathway for methane production. Efficient thermophilic biomethanation of rice straw without thermochemical pretreatment using cattle dung supplemented with M. thermautotrophicus is reported for the first time.


Assuntos
Reatores Biológicos , Metano/biossíntese , Microbiota , Oryza/metabolismo , Anaerobiose , Animais , Carbono/metabolismo , Bovinos , Euryarchaeota/metabolismo , Hidrólise , Methanobacteriaceae/metabolismo , Nitrogênio/metabolismo
16.
MycoKeys ; (40): 89-110, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364831

RESUMO

An extended incubation strategy to culture slow growing members of anaerobic fungi resulted in the isolation of a novel anaerobic fungus from the rumen of a goat after 15 days. The novel genus, represented by type strain G1SC, showed filamentous monocentric thallus development and produced uniflagellate zoospores, hence, showing morphological similarity to the genera Piromyces, Buwchfawromyces, Oontomyces and Pecoramyces. However, strain G1SC showed genetic similarity to the genus Anaeromyces, which, though produces uniflagellate zoospore, also exhibits polycentric thallus development. Moreover, unlike Anaeromyces, strain G1SC did not show hyphal constrictions, instead produced a branched, determinate and anucleate rhizoidal system. This fungus also displayed extensive sporangial variations, both exogenous and endogenous type of development, short and long sporangiophores and produced septate sporangia. G1SC utilised various complex and simple substrates, including rice straw and wheat straw and produced H2, CO2, formate, acetate, lactate, succinate and ethanol. Phylogenetic analysis, using internal transcribed spacer 1 (ITS1) and D1/D2 domain of large-subunit (LSU) rRNA locus, clearly showed a separate lineage for this strain, near Anaeromyces. The ITS1 based geographical distribution studies indicated detection of environmental sequences similar (93-96%) to this strain from cattle faeces. Based on morphological and molecular characterisation results of strain G1SC, we propose a novel anaerobic fungus Liebetanzomycespolymorphus gen. et sp. nov., in the phylum Neocallimastigomycota.

17.
3 Biotech ; 8(6): 281, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29881659

RESUMO

Aerobic methanotrophs associated with Indian rice plants have rarely been cultivated. In the present study, we cultured aerobic methanotrophic bacteria from the rhizosphere regions of rice plants. Rhizospheric soils from seven rice landraces traditionally grown and maintained by tribal people in Jawhar region belonging to part of the Western Ghats in India, were used. Seven methanotrophic cultures were isolated from the last positive dilution (10- 4). Methanotrophs were identified by analyzing the partial methane monooxygenase gene, pmoA gene and three of these belonged to the genus Methylocaldum (gammaproteobacterial, Type I methanotrophs) and four belonged to the genus Methylocystis (alphaproteobacterial, Type II methanotrophs). We present here the first report on the cultivation of methanotrophs from Indian traditional rice landraces originating from a biodiversity hotspot.

18.
Anaerobe ; 50: 64-68, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29432849

RESUMO

Six genera of hydrogenotrophic methanogens, namely Methanobrevibacter, Methanobacterium, Methanocorpusculum, Methanothermobacter, Methanoculleus, and Methanospirillum were cultivated from diverse environmental niches like rumen, feces, gut, and sediments using BY medium. We also report a putative novel genus and two novel species of methanogens isolated from termite, Indian star tortoise, and green iguana.


Assuntos
Microbiologia Ambiental , Hidrogênio/metabolismo , Metano/metabolismo , Microbiota , Animais , Fezes/microbiologia , Sedimentos Geológicos/microbiologia , Metagenoma , Metagenômica/métodos , Filogenia , RNA Ribossômico 16S , Rúmen/microbiologia
19.
Front Microbiol ; 8: 559, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28439260

RESUMO

Innovations in next-generation sequencing technology have introduced new avenues in microbial studies through "omics" approaches. This technology has considerably augmented the knowledge of the microbial world without isolation prior to their identification. With an enormous volume of bacterial "omics" data, considerable attempts have been recently invested to improve an insight into virosphere. The interplay between bacteriophages and their host has created a significant influence on the biogeochemical cycles, microbial diversity, and bacterial population regulation. This review highlights various concepts such as genomics, transcriptomics, proteomics, and metabolomics to infer the phylogenetic affiliation and function of bacteriophages and their impact on diverse microbial communities. Omics technologies illuminate the role of bacteriophage in an environment, the influences of phage proteins on the bacterial host and provide information about the genes important for interaction with bacteria. These investigations will reveal some of bio-molecules and biomarkers of the novel phage which demand to be unveiled.

20.
Genome Announc ; 5(15)2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28408670

RESUMO

Marinobacter sp. strain AC-23 was isolated from Kongsfjorden in the Arctic. Here, we report the first draft genome sequence of a putative novel species of the genus Marinobacter comprising 4,149,715 bp, with a mean G+C content of 54.4%. The draft genome sequence will aid in understanding the psychrophilic and sea ice-specific lifestyle.

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