The chbG gene of the chitobiose (chb) operon of Escherichia coli encodes a chitooligosaccharide deacetylase.

ABSTRACT: The chb operon of Escherichia coli is involved in the utilization of the β-glucosides chitobiose and cellobiose. The function of chbG (ydjC), the sixth open reading frame of the operon that codes for an evolutionarily conserved protein is unknown. We show that chbG encodes a monodeacetylase that is essential for growth on the acetylated chitooligosaccharides chitobiose and chitotriose but is dispensable for growth on cellobiose and chitosan dimer, the deacetylated form of chitobiose. The predicted active site of the enzyme was validated by demonstrating loss of function upon substitution of its putative metal-binding residues that are conserved across the YdjC family of proteins. We show that activation of the chb promoter by the regulatory protein ChbR is dependent on ChbG, suggesting tha

SUBMITTER: Verma SC 

PROVIDER: S-EPMC3430350 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature