Staphostatins resemble lipocalins, not cystatins in fold

• Published in: Protein science Vol. 12; no. 10; pp. 2252 - 2256
• Main Authors: Rzychon, Malgorzata, Filipek, Renata, Sabat, Artur, Kosowska, Klaudia, Dubin, Adam, Potempa, Jan, Bochtler, Matthias
• Format: Journal Article
• Language: English
• Published: Bristol Cold Spring Harbor Laboratory Press 01.10.2003
• Subjects: Carrier Proteins - chemistry; Crystallization; Crystallography, X-Ray; Cystatins - chemistry; Cysteine Endopeptidases - chemistry; cysteine protease inhibitor; Databases, Protein; GST, glutathione‐S‐transferase; Humans; Lipocalin 1; Models, Molecular; Protein Folding; Protein Structure, Secondary; Protein Structure, Tertiary; SspC; staphostatin; Structural Homology, Protein; β‐barrel
• ISSN: 0961-8368; 1469-896X
• DOI: 10.1110/ps.03247703

Staphostatins are the endogenous inhibitors of the major secreted cysteine proteases of Staphylococcus aureus, the staphopains. Here, we present the 1.4 Å crystal structure of staphostatin B and show that the fold can be described as a fully closed, highly sheared eight‐stranded β‐barrel. Thus, staphostatin B is related to β‐barrel domains that are involved in the inhibition or regulation of proteases of various catalytic types and to the superfamily of lipocalins/cytosolic fatty acid binding proteins. Unexpectedly for a cysteine protease inhibitor, staphostatin B is not significantly similar to cystatins.