7ZOO

Carbohydrate binding domain CBM92-B from a multi-catalytic glucanase-chitinase from Chitinophaga pinensis DSM 2588 in complex with gentiobiose

Summary for 7ZOO

• Entry DOI: 10.2210/pdb7zoo/pdb
• Related: 7ZOH 7ZOI 7ZON 7ZOP
• Descriptor: Glycoside hydrolase family 18, beta-D-glucopyranose (3 entities in total)
• Functional Keywords: beta-trefoil, carbohydrate binding domain, beta-glycan, carbohydrate
• Biological source: Chitinophaga pinensis DSM 2588
• Total number of polymer chains: 2
• Total formula weight: 32893.88

Authors

Mazurkewich, S.,McKee, L.S.,Lu, Z.,Branden, G.,Larsbrink, J. (deposition date: 2022-04-26, release date: 2023-05-10, Last modification date: 2024-05-08)

Primary citation

Hao, M.S.,Mazurkewich, S.,Li, H.,Kvammen, A.,Saha, S.,Koskela, S.,Inman, A.R.,Nakajima, M.,Tanaka, N.,Nakai, H.,Branden, G.,Bulone, V.,Larsbrink, J.,McKee, L.S.
Structural and biochemical analysis of family 92 carbohydrate-binding modules uncovers multivalent binding to beta-glucans.
Nat Commun, 15:3429-3429, 2024

PubMed Abstract: Carbohydrate-binding modules (CBMs) are non-catalytic proteins found appended to carbohydrate-active enzymes. Soil and marine bacteria secrete such enzymes to scavenge nutrition, and they often use CBMs to improve reaction rates and retention of released sugars. Here we present a structural and functional analysis of the recently established CBM family 92. All proteins analysed bind preferentially to β-1,6-glucans. This contrasts with the diversity of predicted substrates among the enzymes attached to CBM92 domains. We present crystal structures for two proteins, and confirm by mutagenesis that tryptophan residues permit ligand binding at three distinct functional binding sites on each protein. Multivalent CBM families are uncommon, so the establishment and structural characterisation of CBM92 enriches the classification database and will facilitate functional prediction in future projects. We propose that CBM92 proteins may cross-link polysaccharides in nature, and might have use in novel strategies for enzyme immobilisation.

PubMed: 38653764
DOI: 10.1038/s41467-024-47584-y

Experimental method

X-RAY DIFFRACTION (1.84 Å)