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kumar, M.

Publications and source records attributed to kumar, M..

2 recordsLinked to original sources

Investigating the eukaryotic host-like SLiMs in microbial mimitopes and their potential as novel drug targets for treating autoimmune diseases

Several pathogens sustain themselves inside the host by mimicking short linear motifs (SLiMs) of the host proteins. SLiMs are short stretches of 3-10 amino acids which are functionally diverse and mediate various signaling and protein-protein interactions (PPIs). Hence, mimicry of the host- SLiMs helps the microbes in modulating/disrupting the host defense mechanisms. This is the first report investigating the evolutionary characteristics and presence of eukaryotic host-like SLiMs in microbial peptides (mimitopes). Evaluation of the selection pressure revealed that 60% of the bacterial and 25% of the viral mimitopes which overlapped with the host-like SLiMs were evolutionarily conserved ({omega} < 1). Interestingly, host-like SLiMs were abundant in mimicry proteins but were less frequent in microbial mimitopes. This reflects that the majority of the pathogens cannot potentially rewire the host PPI networks for their advantage, but some can. Of the 152 bacterial and 43 viral mimitopes investigated only 10 bacterial and 4 viral mimitopes showed SLiMs. This indicates that mimitopes of some pathogens can be explored as novel drug targets for eliminating the etiopathological agent and treating the autoimmune disease, thereof. The repertoire of mimitopes identified here might provide important clues for the discovery of new drugs/protein-based immune-modulatory molecules against the pathogens. Key pointsO_LIMimicry of the host- SLiMs helps the microbes in modulating/disrupting the host defense mechanisms. C_LIO_LIHost-like SLiMs were abundant in mimicry proteins but were less frequent in microbial mimitopes. C_LIO_LIEvaluation of the selection pressure revealed that 60% of the bacterial and 25% of the viral mimitopes which overlapped with the host-like SLiMs were evolutionarily conserved. C_LI

bioinformatics↗

Insights into the Human Gut Virome by Sampling a Population from the Indian Subcontinent

Gut virome plays an important role in human physiology but remains poorly understood. This study reports an investigation of the human gut DNA-virome of a previously unexplored ethnic population through metagenomics of faecal samples collected from individuals residing in Northern India. Analysis shows that, similar to the populations investigated earlier, majority of the identified virome belongs to bacteriophages and a smaller fraction (< 20%) consists of viruses that infect animals, archaea, protists, multiple domains or plants. However, crAss-like phages, in this population, are dominated by the genera VII, VIII and VI. Interestingly, it also reveals the presence of a virus family, Sphaerolipoviridae, which has not been detected in the human gut earlier. Viral families, Siphoviridae, Myoviridae, Podoviridae, Microviridae, Herelleviridae and Phycodnaviridae are detected in all of the analyzed individuals, which supports the existence of a core virome. Lysogeny-associated genes were found in less than 10% of the assembled genomes and a negative correlation was observed in the richness of bacterial and free-viral species, suggesting that the dominant lifestyle of gut phage is not lysogenic. This is in contrast to some of the earlier studies. Further, several hundred high-quality viral genomes were recovered. Detailed characterization of these genomes would be useful for understanding the biology of these viruses and their significance in human physiology. ImportanceViruses are important constituents of the human gut microbiome but it remains poorly understood. The Indian subcontinent is a unique biogeographic region and the Indian population is known to harbour a distinct bacterial microbiome. However, the gut virome in this population has not been investigated earlier. Therefore, in this study, we investigated fecal samples of 12 healthy individuals to analyze their gut virome, through metagenomics.

microbiology↗