These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Group-directed modification of bacteriorhodopsin by arylisothiocyanates. Labeling, identification of the binding site and topology.
    Author: Sigrist H, Allegrini PR, Stauffer K, Schaller J, Abdulaev NG, Rickli EE, Zahler P.
    Journal: J Mol Biol; 1984 Feb 15; 173(1):93-108. PubMed ID: 6321744.
    Abstract:
    Group-directed hydrophobic modification of membrane-integrated protein segments by arylisothiocyanates is applied to bacteriorhodopsin. Labeling of purple membrane with phenylisothiocyanate and 4-N,N'-dimethylamino-azobenzene-4'-isothiocyanate results in covalent modification of a unique lysine epsilon-amino group of bacteriorhodopsin. Lysine residue 41, located in the amino-terminal chymotryptic fragment, has been identified as the arylisothiocyanate binding site by established sequencing techniques. The phenylisothiocyanate binding site is not accessible for the aqueously soluble analog p-sulfophenylisothiocyanate. Furthermore, the acid-induced bathochromic shift of the bound chromophore reagent is not observed following acidification of 4-N,N'-dimethylamino-azobenzene-4'-isothiocyanate-labeled purple membrane. The modification thus occurs in the hydrophobic membrane domain, providing further evidence for intramembraneous disposition of the modified protein segment. Light-induced proton translocation is preserved in reconstituted vesicles containing either phenylisothiocyanate-modified or 4-N,N'-dimethylamino-azobenzene-4'-isothiocyanate-modified bacteriorhodopsin.
    [Abstract] [Full Text] [Related] [New Search]