Abstract:
:The electron spin resonance spectrum of the triplet excited state of Rhodopseudomonas spheroides R-26 reaction centers has been studied after excitation with the polarized narrow-bandwidth output of a tunable dye laser from 520 to 670 nm. A theory is developed relating experimental observables to the angles between the electronic transition dipole moment of the excited chromophore and the principle magnetic axis system of the triplet state of the dimeric trap. Data is presented which demonstrates that the treatment is correct and useful, and angles are obtained for the Q(x) transitions of bacteriopheophytin. High-resolution magnetophotoselection data in the region of the bacteriochlorophyll Q(x) transitions can be combined with polarized photobleaching experiments to provide direct information on the structure of dimeric trap.
journal_name
Proc Natl Acad Sci U S Aauthors
Boxer SG,Roelofs MGdoi
10.1073/pnas.76.11.5636subject
Has Abstractpub_date
1979-11-01 00:00:00pages
5636-40issue
11eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章abstract::DNA "breathing" is a thermally driven process in which base-paired DNA sequences transiently adopt local conformations that depart from their most stable structures. Polymerases and other proteins of genome expression require access to single-stranded DNA coding templates located in the double-stranded DNA "interior,"...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1988-04-01 00:00:00