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Peroumal, D.

Publications and source records attributed to Peroumal, D..

2 recordsLinked to original sources

Commensal fungi Candida albicans modulates dietary high-fat induced alterations in metabolism, immunity, and gut microbiota

Obesity and its associated diseases represent a growing health concern. Despite a strong correlation between gut microbiota and obesity, a limited study is available to suggest the direct involvement of fungus in host physiology. Candida albicans survives as a commensal fungus in the gastrointestinal tract, and its excessive growth causing infections in immune-suppressed individuals is widely accepted. However, any mutualistic relationship that may exist between C. albicans and the host remains outstanding. Here we show that the dietary C. albicans do not cause any noticeable infections, and our metagenomics analyses suggest that it colonizes in the gut and modulates microbiome dynamics which in turn negates the high-fat diet induced uncontrolled body weight gain, metabolic hormonal imbalances, and inflammatory response. Interestingly, adding C. albicans to a non-obesogenic diet stimulates the appetite regulated hormones and helped the mice gain healthy body weight. In concert, our results suggest a mutualism between C. albicans and the host, therefore, contrary to the notion, C. albicans is not always an adversary rather a bonafide admirable companion of the host. Finally, we discuss its potential translational implication as a probiotic especially in obese people or people dependent on high fat calorie intakes to manage obesity and associated complications.

microbiology↗

Human DNA polymerase delta is a pentameric complex with dimeric p12 subunit: Implications in enzyme architecture and PCNA interaction

Human DNA polymerase delta (Pol{delta}), a holoenzyme consisting of p125, p50, p68 and p12 subunits, plays an essential role in all the three DNA transaction processes. Herein, using multiple physicochemical and cellular approaches we found that the p12 protein forms a dimer in solution. In vitro reconstitution and pull-down of cellular Pol{delta} by tagged p12 authenticates pentameric nature of this critical holoenzyme. Further, a consensus PIP motif at the extreme carboxyl terminal tail and a homodimerization domain at the amino-terminus of the p12 subunit were identified. Our mutational analyses of p12 subunit suggest that 3RKR5 motif is critical for dimerization that facilitates p12 binding to IDCL of PCNA via its PIP motif 98QCSLWHLY105. Additionally, we observed that oligomerization of the smallest subunit of Pol{delta}s is evolutionarily conserved as Cdm1 of S. pombe also dimerzes. Thus, we suggest that human Pol{delta} is a pentameric complex with a dimeric p12 subunit; and discuss implications of p12 dimerization in regulating enzyme architecture and PCNA interaction during DNA replication.

molecular biology↗