Structural highlights
Function
[DAAA_BACYM] Acts on the D-isomers of alanine, leucine, aspartate, glutamate, aminobutyrate, norvaline and asparagine. The enzyme transfers an amino group from a substrate D-amino acid to the pyridoxal phosphate cofactor to form pyridoxamine and an alpha-keto acid in the first half-reaction. The second-half reaction is the reverse of the first, transferring the amino group from the pyridoxamine to a second alpha-keto acid to form the product D-amino acid via a ping-pong mechanism. This is an important process in the formation of D-alanine and D-glutamate, which are essential bacterial cell wall components.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The three-dimensional structure of D-amino acid aminotransferase (D-AAT) in the pyridoxamine phosphate form has been determined crystallographically. The fold of this pyridoxal phosphate (PLP)-containing enzyme is completely different from those of any of the other enzymes that utilize PLP as part of their mechanism and whose structures are known. However, there are some striking similarities between the active sites of D-AAT and the corresponding enzyme that transaminates L-amino acids, L-aspartate aminotransferase. These similarities represent convergent evolution to a common solution of the problem of enforcing transamination chemistry on the PLP cofactor. Implications of these similarities are discussed in terms of their possible roles in the stabilization of intermediates of a transamination reaction. In addition, sequence similarity between D-AAT and branched chain L-amino acid aminotransferase suggests that this latter enzyme will also have a fold similar to that of D-AAT.
Crystal structure of a D-amino acid aminotransferase: how the protein controls stereoselectivity.,Sugio S, Petsko GA, Manning JM, Soda K, Ringe D Biochemistry. 1995 Aug 1;34(30):9661-9. PMID:7626635[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Tanizawa K, Masu Y, Asano S, Tanaka H, Soda K. Thermostable D-amino acid aminotransferase from a thermophilic Bacillus species. Purification, characterization, and active site sequence determination. J Biol Chem. 1989 Feb 15;264(5):2445-9. PMID:2914916
- ↑ Peisach D, Chipman DM, Van Ophem PW, Manning JM, Ringe D. Crystallographic study of steps along the reaction pathway of D-amino acid aminotransferase. Biochemistry. 1998 Apr 7;37(14):4958-67. PMID:9538014 doi:10.1021/bi972884d
- ↑ Sugio S, Petsko GA, Manning JM, Soda K, Ringe D. Crystal structure of a D-amino acid aminotransferase: how the protein controls stereoselectivity. Biochemistry. 1995 Aug 1;34(30):9661-9. PMID:7626635
