doi:10.1038/nindia.2018.45 Published online 20 April 2018
By sequencing and comparing the genomes of different strains of a skin bacterium from Indians and North Americans, geneticists have discovered a novel microbial strain that carries unique gene clusters that encode antimicrobial proteins1. This bacterium could potentially be used to develop smart probiotics and cosmetic supplements made of health-promoting live bacteria.
Hundreds of friendly bacterial species thrive on human skin, nourishing and protecting the host. Although there have been reports of new species of skin-inhabiting bacteria, variation within different strains of same species across diverse geographic locations has yet to be identified.
Researchers from the CSIR-Institute of Microbial Technology in Chandigarh, India, led by Prabhu B Patil, compared the whole genome sequence of different strains of the skin bacterium known as Staphylococcus epidermidis from healthy individuals from India and North America.
The Indians have been found to harbour a novel strain that is absent on the skin of healthy Americans. After sequencing its genome, two gene clusters containing genes encoding at least two antimicrobial proteins were detected only in the Indian strains.
Besides protecting the host against disease-causing microbes, the antimicrobials might have played roles in helping the novel strain to adapt to harsh conditions such as humidity, high temperature and intense sunlight in India.
The scientists also identified marker genes that can help distinguish a friendly skin bacterium from a disease-causing one in diverse populations.
1. Sharma, S. et al. Phylogenomic based comparative studies on Indian and American commensal Staphylococcus epidermidis isolates. Front. Microbiol. (2018) doi: 10.3389/fmicb.2018.00333