Characterisation of a highly specific, endogenous inhibitor of cysteine protease from Staphylococcus epidermidis, a new member of the staphostatin family.
Staphostatins, a novel family of cysteine protease inhibitors with a unique mechanism of action and distinct protein fold has recently been discovered. In this report we describe the properties of Staphylococcus epidermidis staphostatin A (EcpB), a new member of the family. As for other staphostatins, the recombinant S. epidermidis staphostatin A exerted very narrow inhibitory specificity, limited to cysteine protease from the same species. The closely related proteases from S. aureus cleaved the inhibitor at the reactive site peptide bond and inactivated it. The EcpB homologue, S. aureus staphostatin A (ScpB), was also susceptible to proteolytic cleavage at the same site by non-target cysteine proteases. Conversely, S. aureus staphostatin B (SspC) was resistant to such proteolysis. The difference in the susceptibility of individual inhibitors to proteolytic cleavage at the reactive site suggests subtle variations in the mechanism of interaction with cysteine proteases.
Dubin
Grzegorz
G
Faculty of Biotechnology, Jagiellonian University, ul. Gronostajowa 7, 30-387 Krakow, Poland. gdubin@mol.uj.edu.pl
Stec-Niemczyk
Justyna
J
Dylag
Tomasz
T
Silberring
Jerzy
J
Dubin
Adam
A
Potempa
Jan
J
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D003546:Cysteine Endopeptidases / Q000187:drug effects* / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D008969:Molecular Sequence Data; D013212:Staphylococcus epidermidis / Q000187:drug effects / Q000201:enzymology*; D013379:Substrate Specificity
D001426:Bacterial Proteins; D002352:Carrier Proteins; D015853:Cysteine Proteinase Inhibitors; C495491:staphostatin A, Staphylococcus epidermidis; D003546:Cysteine Endopeptidases