Nature is the platform of varsity. Among all organisms, microbial world gives a true example, reflecting through their taxonomical characters, psychological properties, genomic and proteomic expression. Many of them are adapted to grow harmoniously under hazardous environments such as acidic or alkaline condition, hot spring environments, dry rock surfaces or deserts, cold water or deep in the sea. Based on their growth conditions, microorganisms have been divided into three broad categories: thermophiles, mesophiles and psychrophiles.
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