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Structure of cellobiose phosphorylase from Clostridium thermocellum in complex with phosphate.

ABSTRACT: Clostridium thermocellum is a cellulosome-producing bacterium that is able to efficiently degrade and utilize cellulose as a sole carbon source. Cellobiose phosphorylase (CBP) plays a critical role in cellulose degradation by catalyzing the reversible phosphate-dependent hydrolysis of cellobiose, the major product of cellulose degradation, into ?-D-glucose 1-phosphate and D-glucose. CBP from C. thermocellum is a modular enzyme composed of four domains [N-terminal domain, helical linker, (?/?)(6)-barrel domain and C-terminal domain] and is a member of glycoside hydrolase family 94. The 2.4 Å resolution X-ray crystal structure of C. thermocellum CBP reveals the residues involved in coordinating the catalytic phosphate as well as the residues that are likely to be involved in substrate binding and discrimination.

SUBMITTER: Bianchetti CM

PROVIDER: S-EPMC3212448 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Structure of cellobiose phosphorylase from Clostridium thermocellum in complex with phosphate.

Bianchetti Christopher M CM Elsen Nathaniel L NL Fox Brian G BG Phillips George N GN

Acta crystallographica. Section F, Structural biology and crystallization communications 20111025 Pt 11

Clostridium thermocellum is a cellulosome-producing bacterium that is able to efficiently degrade and utilize cellulose as a sole carbon source. Cellobiose phosphorylase (CBP) plays a critical role in cellulose degradation by catalyzing the reversible phosphate-dependent hydrolysis of cellobiose, the major product of cellulose degradation, into α-D-glucose 1-phosphate and D-glucose. CBP from C. thermocellum is a modular enzyme composed of four domains [N-terminal domain, helical linker, (α/α)(6) ...[more]

PMID: 22102229

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