Structure of a bacterial sensory receptor. A site-directed sulfhydryl study

J J Falke, A F Dernburg, D A Sternberg, N Zalkin, D L Milligan, D E Koshland
1988 Journal of Biological Chemistry  
Cysteines are substituted at six positions in the aspartate receptor, and these mutant proteins are used to investigate three major facets of receptor structure. 1) The surface of the receptor is examined through measurement of the rate constants for chemical modification of the cysteines by aqueous reagents. Different positions exhibit a range of accessibility (for example, Cys-128 most exposed, Cys-36 most buried). 2) The transmembrane structure of the receptor is determined by reaction of
more » ... cysteines with a membrane-impermeant reagent. 3) The spatial proximities in the folded structure of specific pairs of cysteines are investigated by disulfide bond formation. These studies illustrate the usefulness of site-directed sulfhydryl chemistry in the analysis of protein structure.
pmid:3049592 fatcat:r546tjp3n5a5liwo45e33mqt2y