Abstract:
:Homogeneous soft tissue, as regards its magnetic relaxation properties, is well-modeled by solutions of cross-linked protein (see Koenig and Brown, Prog. NMR Spectr. 22, 487 (1991)). Interactions at the solute-solvent interface alter the hydrodynamics of solvent water, and also couple the solute and solvent proton Zeeman energy reservoirs, giving hydrodynamic and cross-relaxation contributions to water proton relaxation that respond differently to deuteration of solvent. We report measurements of the magnetic field dependence of 1/T1 of water protons in cross-linked bovine serum albumin (BSA), for partially deuterated solvent and, in order to separate these two contributions, of 1/T1 of deuterons. The major experimental finding is that, in addition to recently identified water-binding sites on protein (covering approximately 0.2% of the surface) with water lifetimes of about 1 microsecond, there is another group of sites with lifetimes of about 23 ns, covering approximately 2% of the surface, which are evident in both proton and deuteron data. In addition, we have formulated a theory of interfacial proton-proton magnetic interactions which--with these four parameters, plus two that quantify the protein-water coupling at each site--can account for all the proton and deuteron data, in both native and cross-linked BSA.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Koenig SH,Brown RD 3rddoi
10.1002/mrm.1910300606subject
Has Abstractpub_date
1993-12-01 00:00:00pages
685-95issue
6eissn
0740-3194issn
1522-2594journal_volume
30pub_type
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2014-11-01 00:00:00
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更新日期:2015-01-01 00:00:00
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更新日期:1994-08-01 00:00:00
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更新日期:2019-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910120210
更新日期:1989-11-01 00:00:00
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更新日期:1999-11-01 00:00:00
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更新日期:2010-09-01 00:00:00
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更新日期:2003-07-01 00:00:00
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更新日期:2012-08-01 00:00:00
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更新日期:1991-10-01 00:00:00
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更新日期:2003-08-01 00:00:00
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更新日期:2017-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1990-07-01 00:00:00