1 H NMR assignment and secondary structure of recombinant RGD‐hirudin

• Published in: Magnetic resonance in chemistry Vol. 43; no. 11; pp. 956 - 961
• Main Authors: Liu, Xingang, Yan, Xiaomin, Mo, Wei, Song, Houyan, Dai, Linsen
• Format: Journal Article
• Language: English
• Published: 01.11.2005
• ISSN: 0749-1581; 1097-458X
• DOI: 10.1002/mrc.1651

Abstract The conformation of a new recombinant RGD‐hirudin, which has the activities of anti‐thrombin and anti‐platelet aggregation, was investigated by multi‐dimensional NMR spectroscopy. The 1 H NMR spectra of this protein are assigned in a sequential manner by using a combination of 2D NMR techniques to demonstrate through‐bond and through‐space (<5 Å) connectivities. The secondary structure of recombinant RGD‐hirudin was deduced from chemical shift indices, sequential NOEs and 3 J HNα coupling constants. The results show that the recombinant RGD‐hirudin has two anti‐parallel β‐sheets and no α‐helix, and also that the Arg–Gly–Asp (RGD) binding motif of this protein is located at the end of a long arm, which consists of two anti‐parallel β‐strands (residues 26–31 and 36–41). As the strands are connected by a β‐turn, the recombinant RGD‐hirudin acquires high flexibility and inhibits platelet aggregation more effectively. Copyright © 2005 John Wiley & Sons, Ltd.