This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1kqa
From Proteopedia
|
GALACTOSIDE ACETYLTRANSFERASE IN COMPLEX WITH COENZYME A
Overview
The galactoside acetyltransferase (thiogalactoside transacetylase) of, Escherichia coli (GAT, LacA, EC 2.3.1.18) is a gene product of the, classical lac operon. GAT may assist cellular detoxification by, acetylating nonmetabolizable pyranosides, thereby preventing their reentry, into the cell. The structure of GAT has been solved in binary complexes, with acetyl-CoA or CoA and in ternary complexes with CoA and the, nonphysiological acceptor substrates isopropyl beta-D-thiogalactoside, (IPTG) or p-nitrophenyl beta-D-galactopyranoside (PNPbetaGal). A, hydrophobic cleft that binds the thioisopropyl and p-nitrophenyl aglycones, of IPTG and PNPbetaGal may discriminate against substrates with, hydrophilic substituents at this position, such as lactose, or inducers of, the lac operon. An extended loop projecting from the left-handed parallel, beta helix domain contributes His115, which is in position to facilitate, attack of the C6-hydroxyl group of the substrate on the thioester.
About this Structure
1KQA is a Single protein structure of sequence from Escherichia coli with COA as ligand. Active as Galactoside O-acetyltransferase, with EC number 2.3.1.18 Full crystallographic information is available from OCA.
Reference
Structure of the lac operon galactoside acetyltransferase., Wang XG, Olsen LR, Roderick SL, Structure. 2002 Apr;10(4):581-8. PMID:11937062
Page seeded by OCA on Tue Nov 20 19:37:59 2007
