Primary Citation of Related Structures:   1DXJ
PubMed Abstract: 
The structure of jack bean chitinase was solved at 1.8 A resolution by molecular replacement. It is an alpha-helical protein with three disulfide bridges. The active site is related in structure to animal and viral lysozymes. However, unlike in lysozyme, the architecture of the active site suggests a single-step cleavage ...
The structure of jack bean chitinase was solved at 1.8 A resolution by molecular replacement. It is an alpha-helical protein with three disulfide bridges. The active site is related in structure to animal and viral lysozymes. However, unlike in lysozyme, the architecture of the active site suggests a single-step cleavage. According to this mechanism, Glu68 is the proton donor and Glu90 assists in the reaction by moving towards the substrate and recruiting a water molecule that acts as the nucleophile. In this model, a water molecule was found in contact with Glu90 O(epsilon1) and Thr119 O(gamma) at a distance of 3.0 and 2.8 A, respectively. The model is in accordance with the observed inversion mechanism.
Related Citations: 
Refined Structure of the Chitinase from Barley Seeds at 2.0 A Resolution Song, S. (1996) Acta Crystallogr D Biol Crystallogr 52: 289
Crystal Structure of an Endochitinase from Hordeum Vulgare L. Seeds Hartmonzingoready, E.J. (1993) J Mol Biol 229: 189