A bottom-up approach towards a bacterial consortium for the biotechnological conversion of chitin to L-lysine.

A bottom-up approach towards a bacterial consortium for the biotechnological conversion of chitin to L-lysine. Appl Microbiol Biotechnol. 2021 Feb 01;: Authors: Vortmann M, Stumpf AK, Sgobba E, Dirks-Hofmeister ME, Krehenbrink M, Wendisch VF, Philipp B, Moerschbacher BM Abstract Chitin is an abundant waste product from shrimp and mushroom industries and as such, an appropriate secondary feedstock for biotechnological processes. However, chitin is a crystalline substrate embedded in complex biological matrices, and, therefore, difficult to utilize, requiring an equally complex chitinolytic machinery. Following a bottom-up approach, we here describe the step-wise development of a mutualistic, non-competitive consortium in which a lysine-auxotrophic Escherichia coli substrate converter cleaves the chitin monomer N-acetylglucosamine (GlcNAc) into glucosamine (GlcN) and acetate, but uses only acetate while leaving GlcN for growth of the lysine-secreting Corynebacterium glutamicum producer strain. We first engineered the substrate converter strain for growth on acetate but not GlcN, and the producer strain for growth on GlcN but not acetate. Growth of the two strains in co-culture in the presence of a mixture of GlcN and acetate was stabilized through lysine cross-feeding. Addition of recombinant chitinase to cleave chitin into GlcNAc2, chitin deacetylase to convert GlcNAc2 into GlcN2 and acetate, and glucosaminidase to cleave GlcN2 into G...
Source: Applied Microbiology and Biotechnology - Category: Microbiology Authors: Tags: Appl Microbiol Biotechnol Source Type: research