Three-dimensional structure of YaaE from Bacillus subtilis, a glutaminase implicated in pyridoxal-5'-phosphate biosynthesis.
The structure of YaaE from Bacillus subtilis was determined at 2.5-A resolution. YaaE is a member of the triad glutamine aminotransferase family and functions in a recently identified alternate pathway for the biosynthesis of vitamin B(6). Proposed active residues include conserved Cys-79, His-170, and Glu-172. YaaE shows similarity to HisH, a glutaminase involved in histidine biosynthesis. YaaD associates with YaaE. A homology model of this protein was constructed. YaaD is predicted to be a (beta/alpha)(8) barrel on the basis of sequence comparisons. The predicted active site includes highly conserved residues 211-216 and 233-235. Finally, a homology model of a putative YaaD-YaaE complex was prepared using the structure of HisH-F as a model. This model predicts that the ammonia molecule generated by YaaE is channeled through the center of the YaaD barrel to the putative YaaD active site.
Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Jacob A
JA
Bauer
Eric M
EM
Bennett
Tadhg P
TP
Begley
Steven E
SE
Ealick
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000737:chemistry* / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D005972:Glutaminase / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D011732:Pyridoxal Phosphate / Q000096:biosynthesis; D013329:Structure-Activity Relationship
D001426:Bacterial Proteins; D011732:Pyridoxal Phosphate; D005972:Glutaminase