Regulation of Streptomyces Chitinases by Two-Component Signal Transduction Systems and their Post Translational Modifications: A Review

This article reviews the developments related to Streptomyces chitinases regulation and their post translational modifications. Chitinases are enzymes which cleave chitin, a polymer of N-acetylglucosamine to its monomer. Bacteria produce chitinases to fulfil their nutritional needs since by-products of chitin degradation can serve as a source of carbon and nitrogen. Chitinolytic bacteria such as Streptomyces produce multiple chitinases which act synergistically to degrade crystalline form of chitin. Streptomyces are one of the major producers of chitinases in the soil. Every Streptomyces genome sequenced till date has multiple genes for chitinases. The chitinases resulting from proteolytic cleavage have different specific activities and binding efficiency. Both of the above mentioned factors contribute to complexity of the chitinolytic system. Two component systems (TCS) are the predominant signal transduction system in bacteria that regulate a wide variety of behaviours as well as fundamental processes such as metabolism and motility. Bacteria generally use two-component signal transduction pathways to couple environmental stimuli to adaptive responses. Apart from the generalized behaviours they also regulate specialised processes such as development and virulence. Thus this review focuses on the two component systems of Streptomyces, their mechanism of action, regulation of chitinases by TCS and post-translational modifications.