Chloramphenicol Acetyltransferase: Enzymology and Molecular Biology
- 1 January 1983
- journal article
- review article
- Published by Informa UK Limited in Critical Reviews in Biochemistry
- Vol. 14 (1), 1-46
- https://doi.org/10.3109/10409238309102789
Abstract
Naturally occurring chloramphenicol resistance in bacteria is normally due to the presence of the antibiotic inactivating enzyme chloramphenicol acetyltransferase (CAT) which catalyzes the acetyl-S-CoA-dependent acetylation of chloramphenicol at the 3-hydroxyl group. The product 3-acetoxy chloramphenicol does not bind to bacterial ribosomes and is not an inhibitor of peptidyltransferase. The synthesis of CAT is constitutive in E. coli and other Gram-negative bacteria which harbor plasmids bearing the structural gene for the enzyme, whereas Gram-positive bacteria such as staphylococci and streptococci synthesize CAT only in the presence of chloramphenicol and related compounds, especially those with the same stereochemistry of the parent compound and which lack antibiotic activity and a site of acetylation (3-deoxychloramphenicol). Studies of the primary structures of CAT variants suggest a marked degree of heterogeneity but conservation of amino acid sequence at and near the putative active site. All CAT variants are tetramers composed in each case of identical polypeptide subunits consisting of approximately 220 amino acids. The catalytic mechanism does not appear to involve an acyl-enzyme intermediate although one or more cysteine residues are protected from thiol reeagents by substrates. A highly reactive histidine residue has been implicated in the catalytic mechanism.Keywords
This publication has 232 references indexed in Scilit:
- Analysis of the accuracy and implications of simple methods for predicting the secondary structure of globular proteinsJournal of Molecular Biology, 1978
- Snake toxin secondary structure predictions: Structure activity relationshipsJournal of Molecular Biology, 1977
- β-turns in proteinsJournal of Molecular Biology, 1977
- Directed selective pressure on a β-lactamase to analyse molecular changes involved in development of enzyme functionNature, 1976
- The chloramphenicol receptor site in Escherichia coli in Vivo affinity labeling by monoiodoamphenicolJournal of Molecular Biology, 1976
- Algorithms for prediction of α-helical and β-structural regions in globular proteinsJournal of Molecular Biology, 1974
- Structural principles of the globular organization of protein chains. A stereochemical theory of globular protein secondary structureJournal of Molecular Biology, 1974
- Logical analysis of the mechanism of protein folding: I. Predictions of helices, loops and β-structures from primary structureJournal of Molecular Biology, 1973
- Studies on plasmid replication: I. Plasmid incompatibility and establishment in Staphylococcus aureusJournal of Molecular Biology, 1972
- Chloramphenicol (Chloromycetin).1 IV.1a Chemical StudiesJournal of the American Chemical Society, 1949