4k2m

Publication Abstract from PubMed

NtdA from Bacillus subtilis is a sugar aminotransferase (SAT) that catalyses the PLP-dependent equatorial transamination of 3-oxo-alpha-D-glucose-6-phosphate to form alpha-D-kanosamine-6-phosphate. The crystal structure of NtdA shows that NtdA shares the common aspartate aminotransferase fold (AAT Type 1) with residues from both monomers forming the active site. The crystal structures of NtdA alone, co-crystallized with the product alpha-D-kanosamine-6-phosphate and incubated with the amine donor glutamate reveals three key structures in the mechanistic pathway of NtdA. The structure of NtdA alone reveals the internal aldimine form of NtdA with the cofactor PLP covalently attached to Lys247. Addition of glutamate results in formation of pyridoxamine phosphate. Co-crystallization with kanosamine-6-phosphate results in the formation of the external aldimine. Only alpha-D-kanosamine-6-phosphate is observed in the active site of NtdA, not the beta-anomer. A comparison of the structure and sequence of NtdA with other SATs enables us to propose that the VIbeta family of aminotransferases should be divided into subfamilies based on the catalytic lysine motif.

The structure of NtdA, a sugar aminotransferase involved in the kanosamine biosynthetic pathway in Bacillus subtilis, reveals a new sub-class of aminotransferases.,van Straaten KE, Ko JB, Jagdhane R, Anjum S, Palmer DR, Sanders DA J Biol Chem. 2013 Oct 4. PMID:24097983^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.