Abstract:
:The activity and stability of mushroom tyrosinase were studied in ionic liquid (IL)-containing aqueous systems. The effect of three ILs ([BMIm][PF(6)], [BMIm][BF(4)]), and [BMIm][MeSO(4)], where [BMIm] = 1-butyl-3-methylimidazolium) and their inorganic salts (KMeSO(4), KPF(6), and NaBF(4)) on the enzyme performance was investigated by comparing the kinetic (such as K(m), V(max), optimal pH and temperature, and activation energy) and thermostability parameters (including half-lives, deactivation constants, activation energies for enzyme deactivation, DeltaG*, DeltaH*, and DeltaS*) of the enzyme in the absence and presence of the ILs and their anions. Both the three ILs and their inorganic salts were able to trigger enzyme activation. The enzyme could be stabilized by addition of KMeSO(4) and NaBF(4) but destabilized by the presence of all the three ILs. The substrate selectivity of the enzyme was unchanged. The effect of ILs on enzyme performance can be largely attributed to their ionic nature via interaction with the enzyme structure, the substrate, and the water molecules associated with the enzyme, depending on their kosmotropocity, nucleophilicity, and H-bond basicity. The different influences brought from the ILs and their associated ions indicate the cooperative functioning of both cation and anion of the IL in affecting the enzyme performance.
journal_name
J Biochemjournal_title
Journal of biochemistryauthors
Yang Z,Yue YJ,Huang WC,Zhuang XM,Chen ZT,Xing Mdoi
10.1093/jb/mvn173subject
Has Abstractpub_date
2009-03-01 00:00:00pages
355-64issue
3eissn
0021-924Xissn
1756-2651pii
mvn173journal_volume
145pub_type
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pub_type: 杂志文章
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pub_type: 杂志文章
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doi:10.1093/oxfordjournals.jbchem.a123912
更新日期:1992-09-01 00:00:00
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journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a134952
更新日期:1984-10-01 00:00:00
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pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a130973
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journal_title:Journal of biochemistry
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journal_title:Journal of biochemistry
pub_type: 杂志文章,评审
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更新日期:2014-08-01 00:00:00
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pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a125002
更新日期:1995-12-01 00:00:00
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journal_title:Journal of biochemistry
pub_type: 杂志文章
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更新日期:1976-05-01 00:00:00
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journal_title:Journal of biochemistry
pub_type: 杂志文章
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更新日期:1978-04-01 00:00:00
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更新日期:1999-10-01 00:00:00
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更新日期:2010-03-01 00:00:00
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journal_title:Journal of biochemistry
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更新日期:2009-01-01 00:00:00
abstract::The structure of vibrioferrin, a siderophore from Vibrio parahaemolyticus, was elucidated based on a combination of partial hydrolysis and spectroscopic techniques. HPLC of purified vibrioferrin showed two peaks with an area ratio of approximately 2:1. However, upon reinjection of each of those isolated compounds, the...
journal_title:Journal of biochemistry
pub_type: 杂志文章
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更新日期:1994-05-01 00:00:00