Chitosan is a deacetylated product of chitin produced by chitin deacetylase, an enzyme that hydrolyses acetamido groups of N-acetylglucosamine in chitin. Chitosan is a natural polymer that has great potential in biotechnology and in the biomedical and pharmaceutical industries. Commercially, it is produced from chitin via a harsh thermochemical process that shares most of the disadvantages of a multistep chemical procedure. It is environmentally unsafe and not easily controlled, leading to a broad and heterogeneous range of products. An alternative or complementary procedure exploiting the enzymatic deacetylation of chitin could potentially be employed, especially when a controlled and well-defined process is required. In this study, 20 strains of bacteria were isolated from soil samples collected from different beaches of Chennai, India. Of these 20 bacterial strains, only 2 strains (S3, S14) are potent degrader of chitin and they are also a good producer of the enzyme chitin deacetylase so as to release chitosan. 1. Introduction Chitin, a homopolymer of β (1,4)-linked N-acetyl-glucosamine, is one of the most abundant, easily obtained, and renewable natural biopolymers, second only to cellulose [1]. Chitin is considered the second most plentiful organic resource on the earth next to cellulose and is present in marine invertebrates, insects, fungi, and yeasts. Chitin and its derivatives have high economic value owing to their versatile biological activities and agrochemical applications [2, 3]. Chitin is not soluble in water or in the majority of organic solvents. However, chitosan, prepared from chitin (usually of crab or shrimp shell origin) through chemical N-deacetylation, is water soluble and possesses biological properties such as high biocompatibility and antimicrobial activities. Chitosan is widely used in medical applications including antitumor therapy and cholesterol control, in medicinal membranes, wound dressings, and controlled-released medicinal materials [4]. Recently, chitosan has also been used as a natural substance for the enhancement of seed germination and plant growth and also as an ecologically friendly biopesticide to boost the innate plant defense mechanisms against fungal infections. At present, chitosan is produced by the thermochemical deacetylation of chitin. Thus an envirofriendly bacterial strains-mediated method can be successfully used for the enzymatic deacetylation of chitin, especially when a controlled and well-defined process is required. Chitin deacetylase (CDA), first identified and partially purified from
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