Background Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a threat to public health in India because of its high dissemination, mortality, and limited treatment options. Its genomic variability is reflected in the diversity of sequence types, virulence factors, and antimicrobial resistance (AMR) mechanisms. This study aims to characterize the clonal relationships and genetic mechanisms of resistance and virulence in CRKP isolates in India. Materials and Methods We characterized 344 retrospective K. pneumoniae clinical isolates collected from 8 centers across India collected in 2013–2019. Susceptibility to antibiotics was tested with VITEK 2. Capsular types, multilocus sequence type, virulence genes, AMR determinants, plasmid replicon types, and a single-nucleotide polymorphism phylogeny were inferred from their whole genome sequences. Results Phylogenetic analysis of the 325 Klebsiella isolates that passed quality control revealed 3 groups: K. pneumoniae sensu stricto (n = 307), K. quasipneumoniae (n = 17), and K. variicola (n = 1). Sequencing and capsular diversity analysis of the 307 K. pneumoniae sensu stricto isolates revealed 28 sequence types, 26 K-locus types, and 11 O-locus types, with ST231, KL51, and O1V2 being predominant. blaOXA-48-like and blaNDM-1/5 were present in 73.2% and 24.4% of isolates, respectively. The major plasmid replicon types associated with carbapenase genes were IncF (51.0%) and Col group (35.0%). Conclusion Our study documents for the first time the genetic diversity of K and O antigens circulating in India. The results demonstrate the practical applicability of genomic surveillance and its utility in tracking the population dynamics of CRKP. It alerts us to the urgency for longitudinal surveillance of these transmissible lineages.

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Citric acid is one of the extensively used organic acids in many industries. There is a worldwide demand for citric acid consumption due to their many industrial applications. It is also considered as a Generally Recognized As Safe (GRAS) compound. In this review, current developments in microbial fermentation processes for citric acid production have been discussed. In food, beverages, milk and sugar processing several biodegradable organic waste materials are generated in large quantities. These include sugarcane bagasse, grape pomace, apple pomace, pineapple pomace, vegetables, tapioca, coconut husk, banana peels, citrus peels, whey and decaying fruits are found to be potential substrates for citric acid production. A significant effect of substrate concentration, inorganic salts, initial sugar concentration, moisture and additives etc on citric acid production have been highlighted for further improvement in fermentation process. Recent developments in upstream and downstream processes for citric acid production are also deeply discussed. This review gives insights for future possibilities of cost effective fermentation process for citric acid production from several cheap raw materials. Formation of citric acid as an industrial byproduct will help to tackle waste disposal issue and also reduce the dependency of industry over other citric acid producers. Thus, the industry would be benefitted ecologically and economically.

We report the persistent circulation of third-generation cephalosporin resistant Salmonella Typhi in Mumbai, linked to the acquisition and maintenance of a previously characterized IncX3 plasmid carrying the ESBL gene blaSHV-12 and the fluoroquinolone resistance gene qnrB7 in the genetic context of a triple mutant also associated with fluoroquinolone resistance.

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