Publication Date:
1994-10-07
Description:
Bacteriorhodopsin was selectively spin labeled at residues 72, 101, or 105 after replacement of the native amino acids by cysteine. Only the electron paramagnetic resonance spectrum of the label at 101 was time-dependent during the photocycle. The spectral change rose with the decay of the M intermediate and fell with recovery of the ground state. The transient signal is interpreted as the result of movement in the C-D or E-F interhelical loop, or in both, coincident with protonation changes at the key aspartate 96 residue. These results link the optically characterized intermediates with localized conformational changes in bacteriorhodopsin during the photocycle.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Steinhoff, H J -- Mollaaghababa, R -- Altenbach, C -- Hideg, K -- Krebs, M -- Khorana, H G -- Hubbell, W L -- EY05216/EY/NEI NIH HHS/ -- GM28289/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1994 Oct 7;266(5182):105-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institut fur Biophysik, Ruhr-Universitat Bochum, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7939627" target="_blank"〉PubMed〈/a〉
Keywords:
Bacteriorhodopsins/*chemistry/genetics
;
Electron Spin Resonance Spectroscopy
;
Light
;
Models, Molecular
;
Mutagenesis, Site-Directed
;
*Protein Conformation
;
Protein Structure, Secondary
;
Spin Labels
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics