1FQG

MOLECULAR STRUCTURE OF THE ACYL-ENZYME INTERMEDIATE IN TEM-1 BETA-LACTAMASE

Summary for 1FQG

• Entry DOI: 10.2210/pdb1fqg/pdb
• Related: 1TEM
• Descriptor: TEM-1 BETA-LACTAMASE, OPEN FORM - PENICILLIN G (3 entities in total)
• Functional Keywords: beta-lactamase, acyl-enzyme, penicillin, class a, hydrolase
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 29263.39

Authors

Strynadka, N.C. (deposition date: 2000-09-05, release date: 2000-11-01, Last modification date: 2024-10-30)

Primary citation

Strynadka, N.C.,Adachi, H.,Jensen, S.E.,Johns, K.,Sielecki, A.,Betzel, C.,Sutoh, K.,James, M.N.
Molecular structure of the acyl-enzyme intermediate in beta-lactam hydrolysis at 1.7 A resolution.
Nature, 359:700-705, 1992

PubMed Abstract: The X-ray crystal structure of the molecular complex of penicillin G with a deacylation-defective mutant of the RTEM-1 beta-lactamase from Escherichia coli shows how these antibiotics are recognized and destroyed. Penicillin G is covalently bound to Ser 70 0 gamma as an acyl-enzyme intermediate. The deduced catalytic mechanism uses Ser 70 0 gamma as the attacking nucleophile during acylation. Lys 73 N zeta acts as a general base in abstracting a proton from Ser 70 and transferring it to the thiazolidine ring nitrogen atom via Ser 130 0 gamma. Deacylation is accomplished by nucleophilic attack on the penicilloyl carbonyl carbon by a water molecule assisted by the general base, Glu 166.

PubMed: 1436034
DOI: 10.1038/359700a0

Experimental method

X-RAY DIFFRACTION (1.7 Å)