Inhibitor binding increases the mechanical stability of staphylococcal nuclease.
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ABSTRACT:
SUBMITTER: Wang CC
PROVIDER: S-EPMC3037565 | biostudies-literature | 2011 Feb
REPOSITORIES: biostudies-literature
Publications
Inhibitor binding increases the mechanical stability of staphylococcal nuclease.
Wang Chien-Chung CC Tsong Tian-Yow TY Hsu Yau-Heiu YH Marszalek Piotr E PE
Biophysical journal 20110201 4
Staphylococcal nuclease (SNase) catalyzes the hydrolysis of DNA and RNA in a calcium-dependent fashion. We used AFM-based single-molecule force spectroscopy to investigate the mechanical stability of SNase alone and in its complex with an SNase inhibitor, deoxythymidine 3',5'-bisphosphate. We found that the enzyme unfolds in an all-or-none fashion at ∼26 pN. Upon binding to the inhibitor, the mechanical unfolding forces of the enzyme-inhibitor complex increase to ∼50 pN. This inhibitor-induced i ...[more]
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