Beta-glucosidase is a glucosidase enzyme that acts upon β1->4 bonds linking two glucose or glucose-substituted molecules (i.e., the disaccharide cellobiose). An exocellulase with specificity for a variety of beta-D-glycoside substrates. It catalyzes the hydrolysis of terminal non-reducing residues in beta-D-glucosides with release of glucose.

Cellulose is largely composed of polymers of beta-bond linked glucose molecules, and beta-glucosidases are required by organisms (some fungi, bacteria, termites) that can consume it.

Lysozyme, an enzyme secreted in tears to prevent bacterial infection of the eye, is also a beta-glucosidase that cleaves β1->4 bonds between N-acetylglucosamine and N-acetylmuramic acid sugars within the peptidoglycan cell walls of gram-negative bacteria.

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• MeSH beta-Glucosidase

[edit] References

1. Nelson DL, Cox MM. "Lehninger: Principles of Biochemistry" 2000 p 306-308
2. GO-database listing 'GO:0016162 cellulose 1,4-beta-cellobiosidase activity'