Expression, Production and Purification of Proteinases from Alternaria sp.

Screening and expression of protease producing 5 strains of Alternaria sp. were obtained from the various places in Chennai, Vellore, Tamilnadu, India. The isolates were positive on tyrosin caesin nitrate agar (1%) and thus are selected as protease producing strain. The microbial growth is revealed by the mycelial dry weight determination. Maximum growth is observed in the case of Alternaria tenuis (0.47 mg). Equally, the maximum growth is observed in Alternaria solani (0.45 mg). Total protein was determined using BSA as standard. Proteinase activity was estimated using casein as the substrate. Finally the enzyme protease was purified by column chromatography. The protein was characterized using SDS-PAGE. Maximum protein content is observed in the case of Alternaria triticola (0.902 mg) and Alternaria triticina (0.753 mg). Maximum proteinase content  is observed in Alternaria triticina  (0.591 mg). This results showed that microbes under study is a good producer of extra cellular protease, which can be beneficial for industries.