Background: Transglutaminase (TGase) belongs to a large family of intracellular and extracellular enzymes that catalyze cross-linking between protein molecules. In this study; isolation, purification, biochemical characterization of a new microbial transglutaminase from Streptomyces fradiae was studied. Methods: The colonies were firstly screened qualitatively using filter paper disc (FPD), and then the enzyme activity was evaluated by quantitative assay. Results: One factor of culture medium optimization showed that the best medium for bacterial growth S. fradiae is ISP NO.4 medium which is supplemented by peptone 1%, casein 1%, glycerol 1%, and yeast extract 1%. Furthermore, the maximum microbial TGase (MTGase) production in the culture medium was achieved at 27 ºC and pH 7. SDS-PAGE analysis revealed a molecular mass of 35 kDa for the purified enzyme. Likewise, MTGase obtained from S. fradiae an optimal activity at 50 ºC and pH 8.5. Conclusion: Based on the features of the purified enzyme, it may be used in various industrial processes to improve the strength, viscosity, elasticity and water holding capacity of products in the food and pharmaceutical industries. MTGase can also be used as a blood clot and meat glue.

Keywords