Partial purification and characterization of serine protease produced through fermentation of organic municipal solid wastes by A3 and A2.

Proteolytic bacteria isolated from municipal solid wastes (MSW) were identified as A3 and A2 based on 16S rDNA sequencing. Protease produced through fermentation of organic MSW by these bacteria under some optimized physicochemical parameters was partially purified and characterized. The estimated molecular mass of the partially purified protease from and was approximately 25 and 38 kDa, respectively. Protease from both sources showed low K 0.3 and 0.5 mg ml and high V 333 and 500 µmole min at 40 °C, and thermodynamics analysis suggested formation of ordered enzyme-substrate (E-S) complexes. The activation energy (E) and temperature quotient (Q) of protease from and were 16.2 and 19.9 kJ/mol, and 1.4 and 1.3 at temperature range from 20 to 40 °C, respectively. Protease of the both bacterial isolates was serine and cysteine type. The protease retained approximately 97% of activity in the presence of sodium dodecyl sulphate. It was observed that the purified protease of could remove blood stains from white cotton cloth and degrade chicken flesh remarkably. Our study revealed that organic MSW can be used as raw materials for bacterial protease production and the protease produced by A3 might be potential for applications.