Localization and mutagenesis of the sorting signal binding site on sortase A from Staphylococcus aureus.
Surface proteins in Gram-positive bacteria are anchored to the cell wall by the action of sortase enzymes. The Staphylococcus aureus sortase A (SrtA) protein anchors proteins by recognizing a cell wall sorting signal containing the amino acid sequence LPXTG. To understand how SrtA binds this sequence, we carried out NMR studies of new peptidyl-cyanoalkene and peptidyl-sulfhydryl inhibitors that contain the sorting signal sequence LPAT. These studies combined with amino acid mutagenesis identified a catalytically important and conserved binding surface formed by residues A118, T180, and I182. Compatible with its recently proposed role as a general base, R197 is also shown to be required for catalysis.
Department of Chemistry and Biochemistry, University of California Los Angeles, 405 Hilgard Avenue, Los Angeles, CA 90095-1570, USA.
Chu Kong
CK
Liew
Brenton T
BT
Smith
Rosemarie
R
Pilpa
Nuttee
N
Suree
Udayar
U
Ilangovan
Kevin M
KM
Connolly
Michael E
ME
Jung
Robert T
RT
Clubb
D000595:Amino Acid Sequence; D019881:Aminoacyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins; D001665:Binding Sites; D002473:Cell Wall / Q000201:enzymology; D003546:Cysteine Endopeptidases; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D011487:Protein Conformation; D015398:Signal Transduction; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics
D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D019881:Aminoacyltransferases; C120542:sortase A; D003546:Cysteine Endopeptidases