Linked Life Data

3191097

Source:http://linkedlifedata.com/resource/pubmed/id/3191097

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
1989-1-9
pubmed:abstractText
An alkaline suspension of light-adapted purple membrane exposed to continuous light showed a large absorption depletion at 580 nm and a small increase around 350 nm. We attribute this absorption change to an efficient photoconversion of bR570 into a photoproduct N (P,R350), which has a major absorption maximum between 550 and 560 nm but has lower absorbance than bR570. N was barely detectable at low pH, low ionic strength, and physiological temperature. However, when the thermal relaxation of N to bR570 was inhibited by increasing pH, increasing ionic strength, and decreasing temperature, its relaxation time could be as long as 10 s at room temperature. N is also photoactive; when it is present in significant concentrations, e.g., accumulated by background light, the flash-induced absorption changes of purple membrane suspensions were affected. Double-excitation experiments showed an M-like photoproduct of N,NM, with an absorption maximum near 410 nm and a much longer lifetime than M412. It may be in equilibrium with an L-like precursor NL. We suggest that N occurs after M412 in the photoreaction cycle and that its photoproduct NM decays into bR570. Thus, at high pH and high light intensity, the overall photoreaction of bR may be approximated by the two-photon cycle bR570----M412----N----(NL----NM)----bR570, whereas at neutral pH and low light intensity it can be described by the one-photon cycle bR570----M412----N----O640----bR570.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5855-63
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Bacteriorhodopsin photoreaction: identification of a long-lived intermediate N (P,R350) at high pH and its M-like photoproduct.
pubmed:affiliation
Institute of Physical and Chemical Research, Saitama, Japan.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't