Abstract

Two-dimensional nuclear magnetic resonance (2d-NMR) dipolar correlation spectroscopy (NOESY) for the calcium binding protein, staphylococcal nuclease, was used to study the conformations in solution as a function of pH. A series of 2d-NOESY spectra of the nuclease H124L-Ca(++)-thymidine 3'5'-bisphosphate ternary complex demonstrated significant pH dependent changes: NOE cross peaks between 46His delta H and an aliphatic proton at 2.66 ppm appeared at pH 10.2, but not at pH 5.5. Some other NOE cross peaks between aromatic and aliphatic protons displayed chemical shift changes in omega 2 or both dimensions (omega 1, omega 2). These results indicated that a local rearrangement accompanies the ionization of the functional groups and has a role in enzyme function.

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 call

Disclaimer: 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.