Structural and thermodynamic insights into chitooligosaccharide binding to human cartilage chitinase 3-like protein 2 (CHI3L2 or YKL-39).

ABSTRACT: Four crystal structures of human YKL-39 were solved in the absence and presence of chitooligosaccharides. The structure of YKL-39 comprises a major (β/α)8 triose-phosphate isomerase barrel domain and a small α + β insertion domain. Structural analysis demonstrates that YKL-39 interacts with chitooligosaccharides through hydrogen bonds and hydrophobic interactions. The binding of chitin fragments induces local conformational changes that facilitate tight binding. Compared with other GH-18 members, YKL-39 has the least extended chitin-binding cleft, containing five subsites for sugars, namely (-3)(-2)(-1)(+1)(+2), with Trp-360 playing a prominent role in the sugar-protein interactions at the center of the chitin-binding cleft. Evaluation of binding affinities obtained from isothermal titrati

SUBMITTER: Ranok A 

PROVIDER: S-EPMC4317009 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature