4ZAH: Crystal Structure Of Sugar Aminotransferase Wece With External Aldimine Vii From Escherichia Coli K-12

Sugar aminotransferases (SATs) are an important class of tailoring enzymes that catalyze the 5'-pyridoxal phosphate (PLP)-dependent stereo- and regiospecific installation of an amino group from an amino acid donor (typically L-Glu or L-Gln) to a corresponding ketosugar nucleotide acceptor. Herein we report the strategic structural study of two homologous C4 SATs (Micromonospora echinospora CalS13 and Escherichia coli WecE) that utilize identical substrates but differ in their stereochemistry of aminotransfer. This study reveals for the first time a new mode of SAT sugar nucleotide binding and, in conjunction with previously reported SAT structural studies, provides the basis from which to propose a universal model for SAT stereo- and regiochemical control of amine installation. Specifically, the universal model put forth highlights catalytic divergence to derive solely from distinctions within nucleotide sugar orientation upon binding within a relatively fixed SAT active site where the available ligand bound structures of the three out of four representative C3 and C4 SAT examples provide a basis for the overall model. Importantly, this study presents a new predictive model to support SAT functional annotation, biochemical study and rational engineering.
PDB ID: 4ZAHDownload
MMDB ID: 128945
PDB Deposition Date: 2015/4/13
Updated in MMDB: 2017/10
Experimental Method:
x-ray diffraction
Resolution: 2.24  Å
Source Organism:
Similar Structures:
Biological Unit for 4ZAH: dimeric; determined by author and by software (PISA)
Molecular Components in 4ZAH
Label Count Molecule
Proteins (2 molecules)
Dtdp-4-amino-4,6-dideoxygalactose Transaminase(Gene symbol: wecE)
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB