TY - JOUR
T1 - Structure and mechanism of a proline-specific aminopeptidase from Escherichia coli
AU - Wilce, Matthew
AU - Bond, Charles S.
AU - Dixon, Nicholas E.
AU - Freeman, Hans C.
AU - Guss, Jules Mitchell
AU - Lilley, Penelope E.
AU - Wilce, Jacqueline Anne
PY - 1998/3/31
Y1 - 1998/3/31
N2 - The structure of the proline-specific amino-peptidase (EC 3.4.11.9) from Escherichia coli has been solved and refined for crystals of the native enzyme at a 2.0-Å resolution, for a dipeptide-inhibited complex at 2.3-Å resolution, and for a low-pH inactive form at 2.7-Å resolution. The protein crystallizes as a tetramer, more correctly a dimer of dimers, at both high and low pH, consistent with observations from analytical ultracentrifuge studies that show that the protein is a tetramer under physiological conditions. The monomer folds into two domains. The active site, in the larger C-terminal domain, contains a dinuclear manganese center in which a bridging water molecule or hydroxide ion appears poised to act as the nucleophile in the attack on the scissile peptide bond of Xaa-Pro. The metal- binding residues are located in a single subunit, but the residues surrounding the active site are contributed by three subunits. The fold of the protein resembles that of creatine amidinohydrolase (creatinase, not a metalloenzyme). The C-terminal catalytic domain is also similar to the single-domain enzyme methionine aminopeptidase that has a dinuclear cobalt center.
AB - The structure of the proline-specific amino-peptidase (EC 3.4.11.9) from Escherichia coli has been solved and refined for crystals of the native enzyme at a 2.0-Å resolution, for a dipeptide-inhibited complex at 2.3-Å resolution, and for a low-pH inactive form at 2.7-Å resolution. The protein crystallizes as a tetramer, more correctly a dimer of dimers, at both high and low pH, consistent with observations from analytical ultracentrifuge studies that show that the protein is a tetramer under physiological conditions. The monomer folds into two domains. The active site, in the larger C-terminal domain, contains a dinuclear manganese center in which a bridging water molecule or hydroxide ion appears poised to act as the nucleophile in the attack on the scissile peptide bond of Xaa-Pro. The metal- binding residues are located in a single subunit, but the residues surrounding the active site are contributed by three subunits. The fold of the protein resembles that of creatine amidinohydrolase (creatinase, not a metalloenzyme). The C-terminal catalytic domain is also similar to the single-domain enzyme methionine aminopeptidase that has a dinuclear cobalt center.
UR - http://www.scopus.com/inward/record.url?scp=0032584215&partnerID=8YFLogxK
U2 - 10.1073/pnas.95.7.3472
DO - 10.1073/pnas.95.7.3472
M3 - Article
C2 - 9520390
AN - SCOPUS:0032584215
VL - 95
SP - 3472
EP - 3477
JO - National Academy of Sciences, Proceedings
JF - National Academy of Sciences, Proceedings
SN - 0027-8424
IS - 7
ER -