3G6M

crystal structure of a chitinase CrChi1 from the nematophagous fungus Clonostachys rosea in complex with a potent inhibitor caffeine

3G6M の概要

• エントリーDOI: 10.2210/pdb3g6m/pdb
• 関連するPDBエントリー: 3G6L
• 分子名称: Chitinase, CAFFEINE (3 entities in total)
• 機能のキーワード: chitinase crchi1, inhibitor, caffeine, glycosidase, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• 由来する生物種: Bionectria ochroleuca (Gliocladium roseum)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 44434.15

構造登録者

Gan, Z.,Yang, J.,Lou, Z.,Rao, Z.,Zhang, K.-Q. (登録日: 2009-02-06, 公開日: 2010-02-16, 最終更新日: 2023-11-01)

主引用文献

Yang, J.,Gan, Z.,Lou, Z.,Tao, N.,Mi, Q.,Liang, L.,Sun, Y.,Guo, Y.,Huang, X.,Zou, C.,Rao, Z.,Meng, Z.,Zhang, K.-Q.
Crystal structure and mutagenesis analysis of chitinase CrChi1 from the nematophagous fungus Clonostachys rosea in complex with the inhibitor caffeine
Microbiology, 156:3566-3574, 2010

PubMed Abstract: Chitinases are a group of enzymes capable of hydrolysing the β-(1,4)-glycosidic bonds of chitin, an essential component of the fungal cell wall, the shells of nematode eggs, and arthropod exoskeletons. Chitinases from pathogenic fungi have been shown to be putative virulence factors, and can play important roles in infecting hosts. However, very limited information is available on the structure of chitinases from nematophagous fungi. Here, we present the 1.8 Å resolution of the first structure of a Family 18 chitinase from this group of fungi, that of Clonostachys rosea CrChi1, and the 1.6 Å resolution of CrChi1 in complex with a potent inhibitor, caffeine. Like other Family 18 chitinases, CrChi1 has the DXDXE motif at the end of strand β5, with Glu174 as the catalytic residue in the middle of the open end of the (β/α)(8) barrel. Two caffeine molecules were shown to bind to CrChi1 in subsites -1 to +1 in the substrate-binding domain. Moreover, site-directed mutagenesis of the amino acid residues forming hydrogen bonds with caffeine molecules suggests that these residues are important for substrate binding and the hydrolytic process. Our results provide a foundation for elucidating the catalytic mechanism of chitinases from nematophagous fungi and for improving the pathogenicity of nematophagous fungi against agricultural pest hosts.

PubMed: 20829286
DOI: 10.1099/mic.0.043653-0

実験手法

X-RAY DIFFRACTION (1.65 Å)