Abstract:
:Heavy atoms, such as bromine or iodine, perturb the excited-state properties of aromatic chromophores through a spin-orbital coupling mechanism. In the present work the use of specifically directed spin-orbital probes to study subtle structural relationships in biopolymers is described. Heavy atoms are introduced into defined sites in biochemical systems and the emission spectrum of a ligand or intrinsic chromophore is monitored for perturbation by the bound heavy atom. This technique is illustrated by a study of acridine dye binding to the copolymer poly(dA-BrdU). The results are interpreted in terms of an "externally" bound dye fraction whose emission is perturbed by the heavy atom in the polymer and an intercalated dye component unperturbed by bromine.
journal_name
Proc Natl Acad Sci U S Aauthors
Galley WC,Purkey RMdoi
10.1073/pnas.69.8.2198subject
Has Abstractpub_date
1972-08-01 00:00:00pages
2198-202issue
8eissn
0027-8424issn
1091-6490journal_volume
69pub_type
杂志文章abstract::An evolutionarily ancient plant hormone receptor complex comprising the α/β-fold hydrolase receptor KARRIKIN INSENSITIVE 2 (KAI2) and the F-box protein MORE AXILLARY GROWTH 2 (MAX2) mediates a range of developmental responses to smoke-derived butenolides called karrikins (KARs) and to yet elusive endogenous KAI2 ligan...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.2006111117
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abstract::Apicomplexan parasites replicate within a protective organelle, called the parasitophorous vacuole (PV). The Toxoplasma gondii PV is filled with a network of tubulated membranes, which are thought to facilitate trafficking of effectors and nutrients. Despite being critical to parasite virulence, there is scant mechani...
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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doi:10.1073/pnas.81.1.110
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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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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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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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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
pub_type: 杂志文章
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更新日期:2007-07-17 00:00:00