Abstract
A comparison of the solution nuclear magnetic resonance (n.m.r.) structures of squash trypsin inhibitor from seeds of the squash Cucurbita maxima with the X-ray structure of a trypsin complex of the inhibitor shows that the n.m.r. and X-ray structures are similar in terms of the global folding and secondary structure. The average atomic root-mean-square difference between the 36 n.m.r. structures on the one hand and the X-ray structure is 0.96 Å for the backbone atoms and 1.95 Å for all heavy atoms. The n.m.r. and X-ray structures exhibit extremely similar conformations of the primary proteinase binding loop. Despite the overall similarity, there are small differences between the mean computed structure and the X-ray structure. The n.m.r. structures have slightly different positions of the segments from residues 16 to 18, and 24 and 25. The n.m.r. results show that the inclusion of stereospecific assignments and precise distance constraints results in a significant improvement in the definition of the n.m.r. structure, making possible a detailed analysis of the local conformations in the protein.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.