Abstract
The troponin I (TnI) inhibitory region (residues 104-115) was synthesized with alpha-14C-labeled Gly-104 and a covalently linked benzoylbenzoyl (BB) moiety at the N terminus to yield a photoactivatable radioactive peptide (BBIp). BBIp was cross-linked to rabbit skeletal muscle troponin C (TnC) to locate the binding site on TnC. The TnC/BBIp mixture was subjected to photolysis in aqueous buffer at pH 7.5 in the presence or absence of Ca2+. A covalent (1:1) cross-linked protein-peptide complex (TnC.BBIp) was isolated in both cases. The cross-linked complex was digested with trypsin, and the peptide fragments were separated by reversed-phase high performance liquid chromatography. The radioactive cross-linked peptide was isolated and further characterized by peptide sequencing and mass spectrometry before and after cyanogen bromide cleavage. The results indicated that Met-155 of TnC was cross-linked to the BB moiety of BBIp in either the presence or absence of Ca2+. The biological activity of both the BBIp peptide and the cross-linked TnC.BBIp complex was studied and a model of the TnC.inhibitory peptide complex was derived using molecular dynamic and energy minimization calculations.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
