Abstract：
:The cytochromes P450 are capable of oxidizing a variety of xenobiotics. Binding of a small molecule heteroactivator to a P450 can alter the coupling of substrate oxidation during P450 catalysis, but the degree to which coupling or shunting via one of the three catalytic cycle branch points is linked to the heteroactivator-modified position of bound substrate is unknown. Using reconstituted CYP2C9, stoichiometric measurements were gathered with three substrates and two classes of heteroactivators to further understand the mechanisms involved in heteroactivation. Heteroactivation of P450 metabolism appeared to involve, but not require, changes in coupling and that increased uncoupling to a specific byproduct like H(2)O(2) does not necessarily correlate to the degree of coupling. In addition, spectroscopy demonstrated that every heteroactivator tested influenced the spin equilibrium of the heme iron even in the presence of saturating substrate suggesting that both substrate proximity and the ability to desolvate the heme can be involved in heteroactivation.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Locuson CW,Gannett PM,Tracy TSdoi
10.1016/j.abb.2006.02.004subject
Has Abstractpub_date
2006-05-15 00:00:00pages
115-29issue
1-2eissn
0003-9861issn
1096-0384pii
S0003-9861(06)00046-4journal_volume
449pub_type
杂志文章abstract：:An inorganic pyrophosphatase (PPase) was purified from thylakoid membrane of spinach leaves to electrophoretic purity by methods including detergent solubilization, ammonium sulfate fractionation, and successive chromatographic techniques. Current protocol yielded about 10% recovery of total activity with a 30-fold pu...
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pub_type： 杂志文章,评审
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pub_type： 杂志文章
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pub_type： 杂志文章
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journal_title：Archives of biochemistry and biophysics
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abstract：:Differential scanning calorimetry measures the heat capacity of states and the excess heat associated with transitions that can be induced by temperature change. The integral of the excess heat capacity is the enthalpy for this process. Despite this potentially intimidating sounding physical chemistry background, DSC ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
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更新日期：2013-03-01 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
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更新日期：2017-10-15 00:00:00
abstract：:Glucosylsphingosine is a potent inhibitor of lysosomal glucocerebrosidase and the broad-specificity, cytosolic beta-glucosidase of human liver. In the present study, it was demonstrated that the broad-specificity beta-glucosidase was also inhibited by galactosylsphingosine. The inhibition was observed when the enzyme ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(85)90672-1
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0440
更新日期：1996-10-01 00:00:00
abstract：:The fertilization layer of Xenopus laevis eggs is formed by the cortical granule lectin binding to its ligand. The binding requires Ca2+, is specific for galactose, and functionally establishes a block to polyspermy at fertilization. We have designed a new enzyme-linked lectin assay for the cortical granule lectin (CG...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0398
更新日期：1996-09-15 00:00:00
