Active site organization of bacterial type I fatty acid synthetase.
Four kinds of active sites of bacterial fatty acid synthetase were mapped on distinct regions within a subunit. Active sites were specifically labeled with radioactive substrates and active-site-directed inhibitors. Labeled enzymes were cleaved with proteases, and the fragments thus produced were identified with respect to specific labels by SDS-polyacrylamide gel electrophoresis and a fluorographic technique. The linear alignment of such fragments in the original subunit was established and when the results were combined with those of our previous work, five active sites were located in three regions as follows. Starting from the N-terminal of the subunit, we located acetyl, malonyl and palmitoyl transferases in the first region, the acyl carrier site in the second region (Morishima & Ikai (1985) Biochim. Biophys. Acta 832, 297-307), and beta-ketoacyl synthetase in the third region. The observed order of active sites of bacterial fatty acid synthetase can be correlated with that of the yeast enzyme, which has two kinds of subunits.
Morishima
N
N
Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo.
Ikai
A
A
D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase / Q000378:metabolism; D000105:Acetyl Coenzyme A / Q000378:metabolism; D001665:Binding Sites; D001667:Binding, Competitive; D001951:Brevibacterium / Q000201:enzymology*; D055598:Chemical Phenomena; D002621:Chemistry; D004228:Dithionitrobenzoic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D064429:Fatty Acid Synthases / Q000378:metabolism*; D005470:Fluorometry; D007460:Iodoacetamide / Q000378:metabolism; D008316:Malonyl Coenzyme A / Q000378:metabolism; D010171:Palmitoyl Coenzyme A / Q000378:metabolism; D010196:Pancreatic Elastase / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding; D014166:Transferases / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism
D010446:Peptide Fragments; D010171:Palmitoyl Coenzyme A; D008316:Malonyl Coenzyme A; D000105:Acetyl Coenzyme A; D004228:Dithionitrobenzoic Acid; D014166:Transferases; D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase; D064429:Fatty Acid Synthases; D010196:Pancreatic Elastase; D014357:Trypsin; D007460:Iodoacetamide