Amino acid residues modulating the activities of staphylococcal glutamyl endopeptidases.
The glutamyl endopeptidase family of enzymes from staphylococci has been shown to be important virulence determinants of pathogenic family members, such as Staphylococcus aureus. Previous studies have identified the N-terminus and residues from positions 185-195 as potentially important regions that determine the activity of three members of the family. Cloning and sequencing of the new family members from Staphylococcus caprae (GluScpr) and Staphylococcus cohnii (GluScoh) revealed that the N-terminal Val residue is maintained in all family members. Mutants of the GluV8 enzyme from S. aureus with altered N-terminal residues, including amino acids with similar properties, were inactive, indicating that the Val residue is specifically required at the N-terminus of this enzyme family in order for them to function correctly. Recombinant GluScpr was found to have peptidase activity intermediate between GluV8 and GluSE from Staphylococcus epidermis and to be somewhat less specific in its substrate requirements than other family members. The 185-195 region was found to contribute to the activity of GluScpr, although other regions of the enzyme must also play a role in defining the activity. Our results strongly indicate the importance of the N-terminal and the 185-195 region in the activity of the glutamyl endopeptidases of staphylococci.
Ono
Toshio
T
Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
Ohara-Nemoto
Yuko
Y
Shimoyama
Yu
Y
Okawara
Hisami
H
Kobayakawa
Takeshi
T
Baba
Tomomi T
TT
Kimura
Shigenobu
S
Nemoto
Takayuki K
TK
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000596:Amino Acids / Q000378:metabolism*; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D012697:Serine Endopeptidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics
D000596:Amino Acids; D011994:Recombinant Proteins; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase