The enzyme protease hydrolyses protein into peptides and amino acids. One of the major sources of protease producing bacterial strains is soil. A total of 30 soil samples were collected aseptically from Changanacherry, and brought to the laboratory. The samples were serially diluted and isolated using Nutrient Agar plates. Skim Agar media was used for the enumeration of protease producing microorganisms. The plates were incubated at 370C for 24-48 hours. The pure culture of 8 colonies exhibiting highest proteolytic activity was obtained by identifying the clear zones. After analysing the optimal growth conditions and antagonistic activities within the strains, 2 isolates were subjected to antibiotic sensitivity test towards twelve different antibiotics, microbiological characteristics, biochemical analysis and extracellular protease enzyme production. Among the 2 isolates, the one which exhibited highest protease production was identified as Bacillus thuringiensis using molecular methods. The results have increased the scope of finding industrially important bacteria from soil which can be used as monoculture or consortium for the degradation of waste on a large scale.

Keywords : Soil, Bacterial Strains, Antagonism, Extracellular Protease.