Lipingzhangella rawalii sp. nov., a novel halophile isolated from Sambhar Salt Lake, Rajasthan, India.

A haloalkaliphilic actinobacterial strain LS1_29T, isolated from an inland hypersaline Sambhar Salt Lake, situated in Rajasthan, India, was subjected to taxonomic characterisation using the polyphasic approach. Cells of the strain were Gram stain positive and aerobic, having reticulate and aerial hyphae. The major fatty acids detected were iso C16:0 (38.23%), anteiso C17:0 (20.52%), iso C18:0 10 methyl (8.09%), iso C18:0 (7.74%) and iso C17:0 (7.48%). The major polar lipids identified were diphosphatidyl glycerol, phosphatidylglycerol, phosphatidylcholine and phospholipids. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the strain belonged to the genus Lipingzhangella with the highest similarity of 94.09% to Lipingzhangella halophila EGI 80537 T and formed a separate clade within the genus Lipingzhangella. The DNA G + C content of genomic DNA of strain LS1_29T was 67.99 mol%. The strain showed the highest orthologous average nucleotide identity (OrthoANI) value of 72.80% and digital DNA-DNA hybridization (dDDH) value of 20.3% with Lipingzhangella halophila EGI 80537 T. Based on the phenotypic, chemotaxonomic and phylogenetic characteristics, strain LS1_29T represents a novel species within the genus Lipingzhangella, for which the name Lipingzhangella rawalii sp. nov. is proposed. The type strain of the type species is LS1_29T (= KCTC 49199 T = JCM 32979 T = MCC 3420 T).

Examining the microbial composition of natural springs in Bhaderwah, Jammu and Kashmir, India.

Natural springs are the main source of water supply for domestic and agricultural use for humans living in the mountainous regions of Asia. Increasing anthropogenic activities with associated waste load, coupled with inadequate sanitation, and contamination of natural water resources and the environment are emerging as important public health issues. We performed a prospective microbiological and physicochemical investigation of water samples from seven distinct natural springs situated at an altitude of 1615 m in the Bhaderwah region of Jammu and Kashmir, India. Bacterial groups belonging to opportunistic pathogens such as members of Moraxellaceae (Acinetobacter), Arcobacteraceae (Pseudoarcobacter), Pseudomonadaceae (Pseudomonas), Oxalobacteraceae (Massilia), and Flavobacteriaceae (Flavobacterium) were observed. The total coliform test indicated an intermediate level of risk of fecal contamination of the springs, except for one site. Through a questionnaire-based survey of the local population, we discovered that around 40% of participants had suffered from waterborne diseases including typhoid (~14%) and diarrhea (~11%). Our data suggests that increased surveillance of fecal contamination and heterotrophic opportunistic pathogens is needed to enhance water quality and reduce health risks for people living in mountainous regions.

Draft Genome Sequence of Ignatzschineria sp. Strain RMDPL8A, a Bacterium Isolated from Landfill Leachate.

The genome of Ignatzschineria sp. strain RMDPL8A was sequenced and analyzed. This draft genome sequence was 2,175,527 bp long, with a GC content of 45.12% and 1,890 protein coding genes.

Whole-Genome Sequencing of the Tropical Marine Bacterium Nocardiopsis dassonvillei NCIM 5124, Containing the Ectoine Biosynthesis Gene Cluster ectABC.

The genome sequence (7,057,619 bp; GC content, 72.07%) of a tropical marine isolate, Nocardiopsis dassonvillei NCIM 5124, containing the biomedically and biotechnologically important gene cluster ectABC is reported here.

A culture-based and culture-independent approach to the study of landfill leachate bacterial and archaeal communities.

The landfill is a convenient and affordable method of municipal solid waste (MSW) management. Landfill leachate contains a heavy load of pollutants and pathogens. Discharge of untreated leachate is the leading cause of surface and groundwater contamination and a threat to public and environmental health. To develop an efficient leachate treatment technology, an in-depth understanding of landfill chemistry and microbiology is essential. In the present manuscript, we conducted a comparative study of three different landfill leachate samples using cultivation-based and culture-independent molecular studies. We cultivated 85 species of aerobic, anaerobic bacteria and archaea from leachate represented by a total of 200 strains using extensive culturomics approaches. Twelve out of 200 cultivated strains of bacteria showed very low 16S rRNA gene sequence similarity (84-98.6%) with their closest relatives and could be the potential novel taxa, the first time cultivated from leachate. Members of the six genera only have 2-5 representatives from past studies from other habitats but first time cultivated from leachate. In addition to bacteria, we also cultivated and characterized different groups of methanogenic archaea. Our chemistry data indicate that leachate is a highly stressed ecosystem with an assemblage of many toxic wastes like sulfur, zinc, mercury, chromium, etc. 16S rRNA gene-based amplicon analysis showed the dominance of (30-55%) methanogens and haloarachaea. Our data suggest that archaea are the significant regulators of leachate ecology, and more in-depth studies with multiple leachate samples are required to understand their role in leachate nutrient cycling and the development of effective leachate treatment technology.

Temporal variation in bacterial community profile on patients' bedsheets in a primary healthcare unit.

Fabrics serve as fomites in spreading nosocomial infections. As a patient is in close contact with bedsheets, it is important to assess the seasonal variation in bacterial diversity on these in healthcare units. The study was conducted to characterise the bacterial diversity on patients' bedsheets across 7 months in a primary healthcare unit. Polyester-cotton blend fabric was stitched on bedsheets, and temporal dynamics of bacterial communities was assessed from May to November 2019. qPCR and amplicon sequencing of 16S rRNA gene was performed for profiling of bacterial community. Results revealed the dominance of Bacillota followed by Pseudomonadota, and Actinomycetota. A seasonal variation was observed in the bacterial load, with maximum values in June. This indicates the impact of environmental conditions on bacterial abundance and composition on fabrics in healthcare unit. The presence of priority pathogens on the patient bedsheets is a human health concern reiterating the need for season-specific laundering protocol.

Natronococcus pandeyae sp. nov., a Novel Haloarchaeon from Sambhar Salt Lake.

A halophilic archaeon, designated strain LS1_42T, was isolated from Sambhar Salt Lake, Rajasthan, India. Cells were non-motile, coccoid, Gram-stain-variable and present in irregular clusters with light pink pigmented colonies. The strain was strictly aerobic and able to grow without Mg2+. Growth of the strain LS1_42T was observed at 25-45 °C, pH 7.0-11.0 and NaCl concentrations of 10-35% (w/v). The nearest phylogenetic neighbor of strain LS1_42T was Natronococcus amylolyticus Ah-36T based on 16S rRNA and rpoB' genes with similarity of 95.4% and 91.9%, respectively. Phylogenetic analysis based on 16S rRNA gene, rpoB' gene and whole-genome sequences indicate that the strain LS1_42T belongs to the genus Natronococcus and is closely related to N. amylolyticus. The genome size was 5.38 Mb with 98.9% completeness. The DNA G + C content of the strain LS1_42T was 63.0 mol%. The average nucleotide identity, average amino acid identity and DNA-DNA hybridization values between LS1_42T and N. amylolyticus Ah-36T were 81.3%, 77.7% and 24.8%, respectively. The major polar lipids detected were phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. On the basis of phenotypic, chemotaxonomic and genome-based analysis, strain LS1_42T represents a novel species within the genus Natronococcus, for which the name Natronococcus pandeyae sp. nov. is proposed. The type strain is LS1_42T (MCC 3654T = JCM 33003T = KCTC 4280T = CGMCC 1.16738T).

Marisediminicola senii sp. nov. isolated from Queen Maud Land, Antarctica.

A Gram-stain-variable, aerobic, orange pigmented, catalase-positive and oxidase-negative, cocci-shaped bacterium, designated SM7_A14T, isolated from glacier fed sediment sample collected from the Queen Maud Land, near India's Maitri station in Antarctica. Phylogenetic analysis based on 16S rRNA gene sequences revealed highest sequence similarity with Marisediminicola antarctica DSM 22350T (97.3 %), demonstrated distinct phylogenetic positioning of strain SM7_A14T within the genus Marisediminicola. Growth of strain SM7_A14T occurs at 5-25 °C (optimum, 20 °C), pH 7.0-10 (optimum, pH 8.0) with 0-5 % NaCl (optimum 1-4 %, w/v). C15 : 0 anteiso, C17 : 0 anteiso, C16 : 0 iso and C15 : 1 anteiso A are the major fatty acids (>5 % of the total fatty acids). The polar lipid profile consisted of diphosphatidylglycerol and phosphatidylglycerol. The average nucleotide identity (ANI) and digital DNA-DNA hybridization values between SM7_A14T and DSM 22350T were 80.3 and 21.3 %, respectively. The genomic DNA G+C content of the strain SM7_A14T was 68.5 %. Distinguishing characteristics based on the polyphasic analysis indicates strain SM7_A14T as a novel species of genus Marisediminicola for which the name Marisediminicola senii sp. nov., is proposed. The type strain is SM7_A14T (=MCC 4327T=JCM 33936T=LMG 31795T).

Contribution of archaea and bacteria in sustaining climate change by oxidizing ammonia and sulfur in an Arctic Fjord.

The present study attempts to investigate the microbial communities and their potential to oxidize ammonia and sulfur at different sites of Arctic Fjord by targeted metagenomics. The high throughput sequencing revealed archaeal Thaumarchaeota (79.3%), Crenarchaeota (10.9%), Euryarchaeota (5.4%), and Woesearchaeota (2.9%) across different depths. In contrast, the bacterial communities depict predominance of Proteobacteria (52.6%), which comprises of dominant genera viz. Sulfurovum (11.2%) and Sulfurimonas (6.3%). Characterizing the metabolic potential of microbial communities with prime focus on the ammonia and sulfur cycling revealed the presence of amoABC and narGHYZ/ nxrAB genes encoding key enzymes. The ammonia cycling coupled with an augmentation of members of Nitrosopumilus belonging to the phylum Thaumarcheaota suggests the vital role of archaeal communities. Similarly, the persistence of chemolithoautotrophic members of Sulfurovum and Sulfurimonas along with the anaerobic genera Desulfocapsa and Desulfobulbus harboring SOX (sulfur-oxidation) system indicates the modulatory role of bacterial communities in sulfur cycling.

Natrialba swarupiae sp. nov., a halophilic archaeon isolated from a hypersaline lake in India.

A haloarchaeal strain (ESP3B_9T) was isolated from the salt pan of Sambhar salt lake, Rajasthan, India. Cells were coccoid, non-motile, Gram-stain-negative and formed reddish-pink pigmented colonies. The strain was aerobic, able to grow at 35-55 °C (optimum, 40 °C), in 20-35 % (25 %) NaCl and pH 8-10 (pH 9). Mg2+ not required for growth. The cells were lysed in distilled water and the minimum NaCl concentration that prevented cell lysis was 5 % w/v. The 16S rRNA gene sequence similarities between strain ESP3B_9T and Natrialba hulunbeirensis JCM 10989T and Natrialba magadii ATCC 43099T were 96.53 and 96.25 % respectively. The similarities of the RNA polymerase subunit B gene between strain ESP3B_9T and N. hulunbeirensis JCM 10989T and N. magadii ATCC 43099T were 84.47 and 84.9 % respectively. Genome sequencing revealed a genome size of 4.20 Mbp with DNA G+C content of 62.5 mol%. The major polar lipids were phosphotidylglycerol and phosphatidylglycerol phosphate methyl esters with minor amounts of unidentified lipids. The results of polyphasic analysis determined that strain ESP3B_9T represents a novel species of the genus Natrialba, for which the name Natrialba swarupiae sp. nov. is proposed. The type strain is ESP3B_9T (MCC 3419T=JCM 33002T=KCTC 4279T=CGMCC 1.16737T).

Cultivation of Diverse Microorganisms from Hypersaline Lake and Impact of Delay in Sample Processing on Cell Viability.

The Sambhar Salt Lake is a halite rich athalassohaline basin, provides a unique opportunity for microbial ecologists to study halophiles. The lake has a high proportion of Na+ and Cl- ions making it a hypersaline ecosystem. In the current study, archaea and bacteria from Sambhar Lake were isolated using two cultivation approaches. A total of 449 isolates were obtained, out of which 13 represent archaeal while 12 represent bacterial genera. Natronococcus and Alkalibacillus were found predominant groups among archaea and bacteria, respectively. Apart from the common genera in both the approaches Alteribacillus, Halobacillus, Halorubrum, Lentibacillus, Natronorubrum, Piscibacillus and Thalassobacillus were found only in the samples processed onsite however only three genera Aliidiomarina, Natrinema and Natronolimnobius were isolated when samples were processed in the laboratory after transportation using the same growth conditions. Other than the isolation of diverse group of organisms 13 putative novel taxa with similarity less than 98% were identified using 16S rRNA gene sequencing.

Subsaxibacter sediminis sp. nov., isolated from Arctic glacial sediment and emended description of the genus Subsaxibacter.

A Gram-stain-negative, yellowish-orange pigmented, rod-shaped, motile bacterium, designated strain ARC111T, was isolated from sediment of Arctic permafrost at Midtre Lovénbreen glacier, Svalbard. 16S rRNA gene based identification of strain ARC111T demonstrated highest sequence similarities to Subsaxibacter broadyi P7T (97.8 %) and Subsaxibacter arcticus JCM30334T (97.5 %) and ≤95.2 % with all other members of the family Flavobacteriaceae. Phylogenetic analysis revealed the distinct positioning of strain ARC111T within the genus Subsaxibacter. The G+C content of ARC111T was 37.8±0.5 mol% while DNA-DNA hybridization depicted 35.6 % relatedness with S. arcticus JCM30334T. Strain ARC111T had C15 : 0iso, C16 : 0iso 3-OH, C15 : 1iso G, C15 : 0anteiso, C16 : 1iso H and C17 : 0iso 3-OH as major (>5 % of the total) cellular fatty acids and MK-6 was the predominant respiratory quinone. The polar lipid profile of strain ARC111T consisted of phosphatidylethanolamine, aminolipid and an unidentified lipid. Strain ARC111T harboured sym-homospermidine as the major polyamine. Characteristic differences obtained using polyphasic analysis of strain ARC111T and its closest relatives suggested that strain ARC111T is a novel species of genus Subsaxibacter, for which the name Subsaxibacter sediminis sp. nov. has been proposed. The type strain is ARC111T (=MCC 3191T=KCTC 42965T=LMG 29783T=GDMCC 1.1201T).