Nitish Kumar Mahato

Draft Genome Sequence of Sphingobium sp. Strain HDIPO4, an Avid Degrader of Hexachlorocyclohexane.

ABSTRACT Sphingobium sp. strain HDIPO4 was isolated from a hexachlorocyclohexane (HCH) dumpsite and degraded HCH isomers rapidly. The draft genome sequence of HDIPO4 (~4.7 Mbp) contains 143 contigs and 4,646 coding sequences with a G+C content of 65%.

Pontibacter ummariensis sp. nov., isolated from a hexachlorocyclohexane contaminated soil.

A Gram-stain-negative, pinkish-red, rod-shaped bacterium designated strain NKM1T was isolated from soil samples contaminated with hexachlorocyclohexane isomers, collected from Ummari village, Lucknow, Uttar Pradesh, India. The strain was characterized by a polyphasic taxonomic approach. 16S rRNA gene sequence analysis showed that strain NKM1T clustered exclusively with members of the genus Pontibacter of the family Cytophagaceae, phylum Bacteroidetes. The 16S rRNA gene sequence similarity to type strains of the genus Pontibacter ranged from 96.7 to 93.8 %, with the highest sequence similarity found with Pontibacter odishensis JC130T (96.7 %). Cells of strain NKM1T were aerobic, non-flagellated and non-motile. Strain NKM1T was catalase- and oxidase-positive but negative for nitrate reduction and hydrolysis of gelatin. The major fatty acids in strain NKM1T were anteiso-C15 : 0, iso-C15 : 0, C16 : 0, C18 : 1ω9c and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The polar lipid profile of strain NKM1T showed the presence of phosphatidylethanolamine and unknown glycolipids as well as aminolipids. sym-Homospermidine was found to be the major polyamine and menaquinone 7 (MK-7) was the major respiratory quinone. The DNA G+C content of strain NKM1T was determined to be 58.6 mol%. Based on phenotypic, chemotaxonomic, physiological and biochemical evidence, it is proposed that isolate NKM1T represents a novel species that belongs to the genus Pontibacter, for which the name Pontibacter ummariensis sp. nov. is proposed. The type strain is NKM1T ( = DSM 100161T = KCTC 42944T = MCC 2777T).

Gut microbiome contributes to impairment of immunity in pulmonary tuberculosis patients by alteration of butyrate and propionate producers: Gut microbiome of TB patients

Tuberculosis (TB) is primarily associated with decline in immune health status. As gut microbiome (GM) is implicated in the regulation of host immunity and metabolism, here we investigate GM alteration in TB patients by 16S rRNA gene and whole-genome shotgun sequencing. The study group constituted of patients with pulmonary TB and their healthy household contacts as controls (HCs). Significant alteration of microbial taxonomic and functional capacity was observed in patients with active TB as compared to the HCs. We observed that Prevotella and Bifidobacterium abundance were associated with HCs, whereas butyrate and propionate-producing bacteria like Faecalibacterium, Roseburia, Eubacterium and Phascolarctobacterium were significantly enriched in TB patients. Functional analysis showed reduced biosynthesis of vitamins and amino acids in favour of enriched metabolism of butyrate and propionate in TB subjects. The TB subjects were also investigated during the course of treatment, to analyse the variation of GM. Although perturbation in microbial composition was still evident after a months administration of anti-TB drugs, significant changes were observed in metagenome gene pool that pointed towards recovery in functional capacity. Therefore, the findings from this pilot study suggest that microbial dysbiosis may contribute to pathophysiology of TB by enhancing the anti-inflammatory milieu in the host.

Pontibacter mucosus sp. nov., isolated from hexachlorocyclohexane-contaminated pond sediment.

A halotolerant, Gram-stain-negative, rod-shaped and light-pink-pigmented bacterial strain, PB3T, was isolated from a pond sediment near a hexachlorocyclohexane-producing factory, located at Chinhat, Lucknow, India. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PB3T formed a distinct phyletic clade along with the members of the genus Pontibacter. The 16S rRNA gene sequence similarity with other members of the genus Pontibacter ranged from 94.5 to 98.9 %. The cells were motile, aerobic, and catalase- and oxidase-positive. The major fatty acids were iso-C15:0, iso-C15:0 3-OH, iso-C17:0 3-OH, C16:1ω5c, summed feature 3 (C16:1ω6c/C16:1ω7c) and summed feature 4 (iso-C17:1I/ anteiso-C17:1 B). The polar lipid profile of strain PB3T showed the presence of phosphatidylethanolamine, an unidentified aminophospholipid, unknown aminolipids and other unknown polar lipids. DNA-DNA hybridization based homology of strain PB3T with respect to its most closely related species, Pontibacter chinhatensis LP51T, was 44.7 %. The DNA G+C content was 53.5 mol%. On the basis of these data, it is proposed that the isolate belongs to the genus Pontibacter and represents a novel species, for which the name Pontibacter mucosus is proposed. The type strain is PB3T (=DSM 100162T=KCTC 42942T).

Draft Genome Sequence of Deinococcus sp. Strain RL Isolated from Sediments of a Hot Water Spring

ABSTRACT Deinococcus sp. strain RL, a moderately thermophilic bacterium, was isolated from sediments of a hot water spring in Manikaran, India. Here, we report the draft genome (2.79 Mbp) of this strain, which contains 62 contigs and 2,614 coding DNA sequences, with an average G+C content of 69.4%.

Lampropedia cohaerens sp. nov., a biofilm forming bacterium isolated from the microbial mats of a hot water spring, located atop the Himalayan ranges at Manikaran, India.

A biofilm-forming, Gram-stain-negative, aerobic, catalase-positive but oxidase-negative strain, designated CT6T, was isolated from the microbial mats (∼45 °C) of a hot water spring, located within the Himalayan ranges at Manikaran, Himachal Pradesh, India. Strain CT6T formed white, smooth colonies with irregular margins. Transmission electron microscopy revealed coccoid, non-flagellated cells with wavy boundaries. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain CT6T belongs to the genus Lampropedia with a sequence similarity value of 95.4 % to the sole member of this genus, Lampropedia hyalina ATCC 11041T. Strain CT6T was found to have phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids. The major cellular fatty acids were C16 : 0, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C14 : 0, C19 : 0ω8c cyclo and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The major respiratory quinone was ubiquinone-8. The major polyamines were putrescine, spermidine and the betaproteobacterial-specific 2-hydroxyputrescine. The DNA G+C content was 63.5 mol%. Based on the genotypic, phenotypic, physiological and biochemical data, strain CT6T is considered to represent a novel species of the genus Lampropedia, for which the name Lampropedia cohaerens sp. nov. is proposed ( = DSM 100029T = KCTC 42939T = MCC 2711T).

Microbial taxonomy in the era of OMICS: application of DNA sequences, computational tools and techniques

The current prokaryotic taxonomy classifies phenotypically and genotypically diverse microorganisms using a polyphasic approach. With advances in the next-generation sequencing technologies and computational tools for analysis of genomes, the traditional polyphasic method is complemented with genomic data to delineate and classify bacterial genera and species as an alternative to cumbersome and error-prone laboratory tests. This review discusses the applications of sequence-based tools and techniques for bacterial classification and provides a scheme for more robust and reproducible bacterial classification based on genomic data. The present review highlights promising tools and techniques such as ortho-Average Nucleotide Identity, Genome to Genome Distance Calculator and Multi Locus Sequence Analysis, which can be validly employed for characterizing novel microorganisms and assessing phylogenetic relationships. In addition, the review discusses the possibility of employing metagenomic data to assess the phylogenetic associations of uncultured microorganisms. Through this article, we present a review of genomic approaches that can be included in the scheme of taxonomy of bacteria and archaea based on computational and in silico advances to boost the credibility of taxonomic classification in this genomic era.

Paracoccus sordidisoli sp. nov., isolated from an agricultural field contaminated with hexachlorocyclohexane isomers

A novel bacterial strain, designated LP91T, was isolated from an agricultural field contaminated with hexachlorocyclohexane (HCH) isomers at Ummari Village, Lucknow, Uttar Pradesh, India. Cells of the strain were aerobic, short rod or coccoid, Gram-stain-negative and non-motile. Colonies of the strain were initially transparent but with time changed to a creamy white colour. Phylogenetic analysis based on the 16S rRNA marker gene showed that it was closely associated with Paracoccus aestuariivivens GHD-30T (99.1 %) and Paracoccus limosus NB88T (98.0 %), followed by Paracoccus laeviglucosivorans 43PT (97.9 %) and Paracoccus marinus KKL-A5T (97.0 %). The DNA-DNA hybridization values of strain LP91T with the closely related type strains mentioned above were below 51.2±0.64 %, confirming it as a distinct species from other known species of the genus Paracoccus. The major cellular fatty acids of strain LP91T were C18 : 0 ω7c/C18 : 0 ω6c and C16 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and aminophospholipid, along with other lipids including glycolipids, aminolipids and other unknown phosphoglycolipids. Spermine was the major polyamine, along with putrescine in a minor amount. Ubiquinone (Q-10) was the sole isoprenoid quinone. Based on the results of phylogenetic, phenotypic and chemotaxonomic analysis, it is proposed that the isolate represents a new species of the genus Paracoccus, for which the name Paracoccus sordidisoli sp. nov. is proposed. The type strain is LP91T (=KCTC 42938T=CCM 8696T=MCC 3128T).

Human Microbiome: Implications on Health and Disease

Human body is a chimera of 40 trillion native cells and 60 trillion foreign cells in the form of microbes colonizing its various organ systems. The sum-total of microorganisms that colonize the human body- collectively referred to as ‘human microbiome or human microbiota’ house majority of the well over 2 million genes present in the human body that has only about 22000 genes of its own, suggesting that the human microbiome might be playing a critical role in its physiology, health and behaviour. It is now clear that the microbiota is acquired within the first 48 hours of birth and the diversity of microbiota is greatly influenced by the mode of birth, genetics, age, sex, stress, nutrition and dietary habit of the individuals. Micro-organisms are known to dwell in almost every part of human body, of which most widely studied micro-habitats include skin, mouth, digestive tract and gut. With the completion of Human Microbiome Project and ongoing research, it has been reported that the changes in human microbiome is associated with obesity, cancer, mental health disorders, asthma and autism. However, many questions are yet to be answered as to whether changes in the composition of microbiota forms the aetiology or is a direct result of a disease. The advancements in research methodologies and emerging field of culture-independent metagenomics approaches are not only likely to enhance our comprehensive understanding on the role of human microbiome on our health but also pave way to treatment of life threatening life-style diseases as well as non-genetic behavioural disorders.