Studies of the mechanism of phenol hydroxylase: mutants Tyr289Phe, Asp54Asn, and Arg281Met.
Studies of the mechanism of phenol hydroxylase: mutants Tyr289Phe, Asp54Asn, and Arg281Met.
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酚羟化酶机制的研究：突变体 Tyr289Phe、Asp54Asn 和 Arg281Met。
DOI：
10.1021/bi010962y
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发表时间：
2001
期刊：
影响因子：
2.9
通讯作者：
Massey,V
中科院分区：
文献类型：
--
作者：
Xu,D;Ballou,DP;Massey,V
Three residues in the active site of the flavoprotein phenol hydroxylase (PHHY) were independently changed by site-directed mutagenesis. One of the mutant forms of PHHY, Tyr289Phe, is reduced by NADPH much slower than is the wild-type enzyme, although it has a slightly higher redox potential than the wild-type enzyme. In the structure of the wild-type enzyme, residue Tyr289 is hydrogen-bonded with the FAD when the latter is at the “out” position but has no direct contact with the flavin when it is “in”. The oxidative half-reaction of PHHY is not significantly affected by this mutation, contrary to the concept that Tyr289 is a critical residue in the hydroxylation reaction [Enroth, C., Neujahr, H., Schneider, G., and Lindqvist, Y. (1998)Structure6, 605−617; Ridder, L., Mullholland, A. J., Rietjens, I. M. C. M., and Vervoort, J. (2000)J. Am. Chem. Soc.122, 8728−8738]. Tyr289 may help stabilize the FAD in the out conformation where it can be reduced by NADPH. For the Asp54Asn mutant form of PHHY, the initial step of the oxidative half-reaction is significantly slower than for the wild-type enzyme. Asp54Asn utilizes less than 20% of the reduced flavin for hydroxylating the substrate with the remainder forming H2O2. Similar changes are observed when Arg281, a residue between Asp54 and the solvent, is mutated to Met. These two residues are suggested to be part of the active site environment the enzyme provides for the flavin cofactor to function optimally in the oxidative half-reaction. In the construction of the mutant forms of PHHY, it was determined that 11 of the previously reported amino acid residues in the sequence of PHHY were incorrect.
儿童抑郁量表：回顾和进一步发展
DOI：
--
发表时间：
1983
期刊：
影响因子：
--
作者：
M. Tisher;M. Lang
通讯作者：
M. Lang
精神障碍住院儿童的绝望、抑郁和自杀倾向。
影响因子：
5.9
作者：
Kazdin,AE;French,NH;Unis,AS;Esveldt-Dawson,K;Sherick,RB
通讯作者：
Sherick,RB
DOI：
10.1111/j.1469-7610.1985.tb00606.x
发表时间：
1985
期刊：
Journal of child psychology and psychiatry, and allied disciplines
影响因子：
--
作者：
N. Rotundo;V. R. Hensley
通讯作者：
V. R. Hensley