Crystal structures of an archaeal chitinase ChiD and its ligand complexes.

Chitinase D (designated as Pc-ChiD) was found in a hyperthermophilic archaeon, Pyrococcus chitonophagus (previously described as Thermococcus chitonophagus), that was isolated from media containing only chitin as carbon source. Pc-ChiD displays chitinase activity and is thermostable at temperatures up to 95°C, suggesting its potential for industrial use. Pc-ChiD has a secretion signal peptide and two chitin-binding domains (ChBDs) in the N-terminal domain.

Engineering of the Hyperthermophilic Archaeon Thermococcus kodakarensis for Chitin-Dependent Hydrogen Production.

is a hyperthermophilic archaeon that harbors a complete set of genes for chitin degradation to fructose 6-phosphate. However, wild-type KOD1 does not display growth on chitin. In this study, we developed a strain that can grow on chitin via genetic and adaptive engineering.

A Structurally Novel Chitinase from the Chitin-Degrading Hyperthermophilic Archaeon Thermococcus chitonophagus.

Unlabelled: A structurally novel chitinase, Tc-ChiD, was identified from the hyperthermophilic archaeon Thermococcus chitonophagus, which can grow on chitin as the sole organic carbon source. The gene encoding Tc-ChiD contains regions corresponding to a signal sequence, two chitin-binding domains, and a putative catalytic domain. This catalytic domain shows no similarity with previously characterized chitinases but resembles an uncharacterized protein found in the mesophilic anaerobic bacterium Clostridium botulinum Two recombinant Tc-ChiD proteins were produced in Escherichia coli, one without the signal sequence [Tc-ChiD(ΔS)] and the other corresponding only to the putative catalytic domain [Tc-ChiD(ΔBD)].