Premium
Evaluating protein:protein complex formation using synchrotron radiation circular dichroism spectroscopy
Author(s) -
Cowieson Nathan P.,
Miles Andrew J.,
Robin Gautier,
Forwood Jade K.,
Kobe Bostjan,
Martin Jennifer L.,
Wallace B. A.
Publication year - 2008
Publication title -
proteins: structure, function, and bioinformatics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.699
H-Index - 191
eISSN - 1097-0134
pISSN - 0887-3585
DOI - 10.1002/prot.21631
Subject(s) - circular dichroism , synchrotron radiation , spectroscopy , protein secondary structure , chemistry , crystallography , protein structure , synchrotron , ultraviolet visible spectroscopy , optics , biochemistry , physics , organic chemistry , quantum mechanics
Circular dichroism (CD) spectroscopy beamlines at synchrotrons produce dramatically higher light flux than conventional CD instruments. This property of synchrotron radiation circular dichroism (SRCD) results in improved signal‐to‐noise ratios and allows data collection to lower wavelengths, characteristics that have led to the development of novel SRCD applications. Here we describe the use of SRCD to study protein complex formation, specifically evaluating the complex formed between carboxypeptidase A and its protein inhibitor latexin. Crystal structure analyses of this complex and the individual proteins reveal only minor changes in secondary structure of either protein upon complex formation (i.e., it involves only rigid body interactions). Conventional CD spectroscopy reports on changes in secondary structure and would therefore not be expected to be sensitive to such interactions. However, in this study we have shown that SRCD can identify differences in the vacuum ultraviolet CD spectra that are significant and attributable to complex formation. Proteins 2008. © 2007 Wiley‐Liss, Inc.