1LF1

Crystal Structure of Cel5 from Alkalophilic Bacillus sp.

Summary for 1LF1

• Entry DOI: 10.2210/pdb1lf1/pdb
• Descriptor: Cel5 (2 entities in total)
• Functional Keywords: cellulose degradation, hydrolase
• Biological source: Bacillus subtilis
• Total number of polymer chains: 1
• Total formula weight: 34502.59

Authors

Shaw, A.,Bott, R.,Vonrhein, C.,Bricogne, G.,Power, S.,Day, A.G. (deposition date: 2002-04-10, release date: 2002-07-03, Last modification date: 2024-02-14)

Primary citation

Shaw, A.,Bott, R.,Vonrhein, C.,Bricogne, G.,Power, S.,Day, A.G.
A novel combination of two classic catalytic schemes.
J.Mol.Biol., 320:303-309, 2002

PubMed Abstract: The crystal structure of an alkaline Bacillus cellulase catalytic core, from glucoside hydrolase family 5, reveals a novel combination of the catalytic machinery of two classic textbook enzymes. The enzyme has the expected two glutamate residues in close proximity to one another in the active-site that are typical of retaining cellulases. However, the proton donor, glutamate 139 is also unexpectedly a member of a serine-histidine-glutamate catalytic triad, forming a novel combination of catalytic machineries. Structure and sequence analysis of glucoside hydrolase family 5 reveal that the triad is highly conserved, but with variations at the equivalent of the serine position. We speculate that the purpose of this novel catalytic triad is to control the protonation of the acid/base glutamate, facilitating the first step of the catalytic reaction, protonation of the substrate, by the proton donor glutamate. If correct, this will be a novel use for a catalytic triad.

PubMed: 12079387
DOI: 10.1016/S0022-2836(02)00387-X

Experimental method

X-RAY DIFFRACTION (1.7 Å)