 |
|
Title
|
|
Crystal structure of a D-amino acid aminotransferase: how the protein controls stereoselectivity.
|
|
|
Authors
|
|
S.Sugio,
G.A.Petsko,
J.M.Manning,
K.Soda,
D.Ringe.
|
|
|
Ref.
|
|
Biochemistry, 1995,
34,
9661-9669.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
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.
|
|
|
|