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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 ℃, 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 ℃ and belonged to the genera Methanosarcina and Methanobacterium. At 55 ℃, 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 ℃, only members of the genus Methanothermobacter (5; 2 species) were isolated, whereas no methanogen could be cultured at 85 ℃. Ours is the first study that documents the extensive range of cultivable methanogenic archaea inhabiting hot springs across various geothermal provinces of India., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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 SV96 T (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 SV96 T , 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.

We report for the first time 2 cases of multidrug-resistant Burkholderia cenocepacia J2315 isolated from blood samples of patients without cystic fibrosis from a pediatric unit in a hospital in India. The first patient presented with community-acquired bacteremia, and the second patient was immunocompromised and developed hospital-acquired infection approximately 17 days after admission. The isolates from both patients were multidrug-resistant and strong biofilm producers. Surveillance cultures identified the secondary sources of the infections, but not the primary sources., (Copyright © 2011 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

Background & Objectives: Antibiotic resistant bacterial nosocomial infections are a leading problem in intensive care units (ICU). Present investigation was undertaken to know antibiotic resistance in Acinetobacter baumannii and some other pathogens obtained from clinical samples from ICU causing nosocomial infections. Special emphasis was given on plasmid mediated transferable antibiotic resistance in Acinetobacter., Methods: The clinical specimens obtained from ICU, were investigated to study distribution of nosocomial pathogens (272) and their antibiotic resistance profile. Acinetobacter isolates were identified by API2ONE system. Antimicrobial resistance was studied with minimum inhibitory concentration (MIC) by double dilution agar plate method. The plasmid profile of 26 antibiotic resistant isolates of Acinetobacter was studied. Curing of R-plasmids was determined in three antibiotic resistant plasmid containing A. baumannii isolates. Plasmid transfer was studied by transformation., Results: Major infections found in ICU were due to Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pyogenes. The infection rate was maximum in urinary tract (44.4%) followed by wound infections (29.4%), pneumonia (10.7%) and bronchitis (7.4%). Acinetobacter isolates displayed high level of antibiotic resistance (up to 1024microg/ml) to most of antibiotics. More than 90 per cent isolates of Acinetobacter were resistant to a minimum of 23 antibiotics. Plasmid profile of Acinetobacter isolates showed presence of 1-4 plasmids. Ethidium bromide cured plasmids pUPI280, pUPI281, pUPI282 with curing efficiencies 20, 16 and 11 per cent respectively while acridine orange cured plasmids pUPI280, pUPI281 with curing efficiencies 7 and 18 per cent retrospectively. Transformation frequency of E. coli HB101 with pUPI281 was 4.3 x 10(4) transformants/microg plasmid DNA., Interpretation & Conclusions: A. baumannii was found to be associated with urinary tract infections, respiratory tract infections, septicaemia, bacteraemia, meningitis and wound infections. A. baumannii displayed higher resistance to more number of antibiotics than other nosocomial pathogens from ICU. Antibiotic sensitivity of A. baumannii cured isolates confirmed plasmid borne nature of antibiotic resistance markers. Transfer of antibiotic resistant plasmids from Acinetobacter to other nosocomial pathogens can create complications in the treatment of the patient. Therefore, it is very important to target Acinetobacter which is associated with nosocomial infections.