Genomic and proteomic study of Andreprevotia ripae isolated from an anthill reveals an extensive repertoire of chitinolytic enzymes

ABSTRACT: Chitin is an abundant natural polysaccharide that is hard to degrade because of its crystalline nature and because it is often found embedded in robust co-polymeric materials containing other polysaccharides, proteins and minerals. Thus, it is of interest to study the enzymatic machineries of highly specialized microbes found in chitin-rich environments. We describe a genomic and proteomic analysis of the chitinolytic machinery of Andreprevotia ripae, a Gram-negative bacterium that was isolated from an anthill. The genome of A. ripae encodes four secreted family GH19 chitinases of which two were detected, both being upregulated during growth on chitin. In addition, the genome encodes 25 secreted GH18 chitinases, of which 17 were detected and 12 were upregulated during growth on chitin. Finally, the single lytic polysaccharide monooxygenase (LPMO) of A. ripae, predicted to be chitin-active based on sequence characteristics and the presence of chitin-binding domains, was strongly upregulated during growth on chitin. Whereas 66 % of the 29 secreted chitinases contained two carbo¬hydrate-binding modules (CBMs) known for binding to chitin, this fraction was 93 % (13 out of 14) for the chitinases that were upregulated during growth on chitin, suggesting an important role for these CBMs. Next to demonstrating an unprecedentedly large multiplicity of upregulated chitinases, the present study also revealed several chitin-induced proteins that contain chitin-binding domains but lack a known catalytic function. These proteins are interesting targets for discovery of enzymes used by Nature to convert chitin-rich biomass.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Andreprevotia Sp. Igb-42

SUBMITTER: Magnus Arntzen  

LAB HEAD: Vincent G. H. Eijsink

PROVIDER: PXD025087 | Pride | 2021-06-10

REPOSITORIES: Pride