Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2010-6-30
pubmed:abstractText
We have found that extensively washed purple membrane has about 1 calcium and 3-4 magnesium ions bound per bacteriorhodopsin molecule. When these divalent cations are removed by any of a variety of means, the pigment changes its color from purple to blue (lambda(max) approximately 600 nm). This blue pigment, which can be formed at near neutral pH, is probably very similar to blue species formed when the pH of a purple membrane sample is lowered to approximately 2. When any of a wide variety of cations are added to a blue membrane preparation, the characteristic purple color of bacteriorhodopsin returns. Divalent and trivalent cations are much more efficient than monovalent cations in restoring the purple color and are effective at a ratio approaching one cation per pigment molecule. Besides shifting the absorption spectrum, removal of the divalent cations drastically alters the photochemical cycle of bacteriorhodopsin, including abolishing the unprotonated Schiff base (M-type) intermediate. Finally, lanthanum not only displaces the divalent cations normally bound to the purple membrane but also greatly reduces both the rate of decay of the M412 intermediate and proton uptake.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-1144313, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-26337, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-31300, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-35226, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-37905, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-39590, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-4940442, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-6287921, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-6321172, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-6514811, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-6830763, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-6929535, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-7241089, http://linkedlifedata.com/resource/pubmed/commentcorrection/16593536-7260274
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Jan
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
396-400
pubmed:dateRevised
2010-9-14
pubmed:year
1985
pubmed:articleTitle
Cation binding by bacteriorhodopsin.
pubmed:affiliation
University of Illinois, Department of Physiology and Biophysics, 407 South Goodwin Avenue, 524 Burrill Hall, Urbana, IL 61801.
pubmed:publicationType
Journal Article