Linked Life Data

1420198

Source:http://linkedlifedata.com/resource/pubmed/id/1420198

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
44
pubmed:dateCreated
1992-12-8
pubmed:abstractText
Light-induced P+QB-/PQB FTIR difference spectra of reaction centers (RCs) have been obtained from chromatophores lacking light-harvesting B800-850 antenna for Rhodobacter capsulatus wild type (WT) and for the two mutants HisM200-->Leu and HisL173-->Leu. The primary donor (P) in both mutants consists of a bacteriochlorophyll-bacteriopheophytin heterodimer. The most prominent difference between the WT and the mutant spectra is in the 1600-1200-cm-1 region. The WT spectrum displays large positive bands at approximately 1290, 1500-1430, and 1580-1530 cm-1. These three bands are either small or altogether absent in the heterodimer spectra. In addition, both heterodimer spectra compare well with the electrochemically generated BChla+/BChla spectrum [Mäntele, W.G., Wollenweber, A. M., Nabedryk, E., & Breton, J. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 8468-8472]. These observations indicate that the positive charge is localized on the monomeric BChl in the heterodimers. The overall shape of the ester and keto C = O signals in the BChla+/BChla spectrum is maintained in the in situ spectra although significant differences are observed in the frequency, width, and splitting of the bands. The shape of the signal at 1757/1744 cm-1 in HisL173-->Leu is comparable to the 1751/1737-cm-1 signal of BChla+/BChla in tetrahydrofuran, indicating a free 10a ester C = O of PM in HisL173-->Leu. The reduced amplitude of the negative 1740-cm-1 feature in both HisM200-->Leu and WT spectra suggests a hydrogen-bonded 10a ester C = O for PL.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10852-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Probing the primary donor environment in the histidineM200-->leucine and histidineL173-->leucine heterodimer mutants of Rhodobacter capsulatus by light-induced Fourier transform infrared difference spectroscopy.
pubmed:affiliation
Département de Biologie Cellulaire et Moléculaire, Centre d'Etudes Nucléaires de Saclay, Gif-sur-Yvette, France.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't