Anchor structure of staphylococcal surface proteins. II. Cooh-terminal structure of muramidase and amidase-solubilized surface protein.
Surface proteins of the Gram-positive organism Staphylococcus aureus are anchored to the bacterial cell wall by a transpeptidation mechanism during which the polypeptide is cleaved between the threonine (T) and the glycine (G) of the LPXTG motif. The carboxyl of threonine is subsequently amide linked to the amino of the pentaglycyl cross-bridge within the staphylococcal peptidoglycan. Previous work examined the anchor structure of surface proteins solubilized from the peptidoglycan by treatment with lysostaphin or phi11 hydrolase and identified COOH-terminally linked triglycyl or L-Ala-D-iGln-L-Lys(Gly5)-D-Ala and MurNAc-[L-Ala-D-iGln-L-Lys(Gly5)-D-Ala](beta1-4)-GlcNAc, respectively. Here, we report the anchor structure of surface proteins solubilized with N-acetylmuramidase and N-acetylmuramyl-L-alanine amidase. N-Acetylmuramidase-released surface protein was linked to MurNAc-[L-Ala-D-iGln-L-Lys(Gly5)-D-Ala](beta1-4)-GlcNAc, whereas N-acetylmuramyl-L-alanine amidase treatment of the cell wall solubilized surface proteins linked to L-Ala-D-iGln-L-Lys(Gly5)-D-Ala. Most, but not all, anchor structures were cross-linked to other cell wall subunits, in which the D-alanyl at position four was amide linked to the pentaglycyl of a neighboring wall peptide.
Navarre
W W
WW
Department of Microbiology and Immunology, UCLA School of Medicine, Los Angeles, California 90095, USA.
Ton-That
H
H
Faull
K F
KF
Schneewind
O
O
D000581:Amidohydrolases / Q000378:metabolism*; D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D001483:Base Sequence; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000378:metabolism; D017931:DNA Primers; D006868:Hydrolysis; D008969:Molecular Sequence Data; D009113:Muramidase / Q000378:metabolism*; D010457:Peptidoglycan / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013211:Staphylococcus aureus / Q000378:metabolism*
D001425:Bacterial Outer Membrane Proteins; D017931:DNA Primers; D010457:Peptidoglycan; D009113:Muramidase; D000581:Amidohydrolases; C019665:amidase