Crystallization of the NAD-dependent malic enzyme from the parasitic nematode Ascaris suum.
Crystallization of the NAD-dependent malic enzyme from the parasitic nematode Ascaris suum.
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来自寄生线虫蛔虫的 NAD 依赖性苹果酸酶的结晶。
DOI:
10.1016/0022-2836(92)90971-l
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发表时间:
1992
影响因子:
5.6
通讯作者:
Harris,BG
中科院分区:
文献类型:
--
作者:
Clancy,LL;Rao,GS;Finzel,BC;Muchmore,SW;Holland,DR;Watenpaugh,KD;Krishnamurthy,HM;Sweet,RM;Cook,PF;Harris,BG
The malic enzyme from muscle mitochondria of the parasitic nematode Ascaris suum is a tetramer of 65 kDa monomers that catalyzes the oxidative decarboxylation of malate to pyruvate and CO 2 with NAD cofactor as oxidant. This malic enzyme is critical to the nematode for muscle function under anaerobic conditions. Unlike mammalian versions of the enzyme such as that found in rat liver, which require NADP as cofactor, the nematode version is an NAD-dependent enzyme. We report the crystallization of samples of the nematode enzyme at room temperature from pH 7.5 solutions of polyethylene glycol 4000 containing magnesium sulfate, NAD and sodium tartronate. Immediately upon mixing of protein and precipitant solutions, a marked precipitation of the protein occurs. Out of this precipitate, crystals appear almost immediately, most commonly in a truncated cube form that can grow to 0.5 to 0.7 mm on a cube edge in two to three days. The crystals are trigonal, space group P3 1 21 or its enantiomer, with a= b= 131.2 (7) A ̊, c= 152.6 (9) A ̊, and two monomers per asymmetric unit. Fresh crystals diffract X-radiation from a synchrotron source (λ= 0.95 Å) to about 3.0 Å resolution. Rotational analysis of Patterson functions indicates that the malic enzyme tetramer has 222 symmetry.
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影响因子:
4.8
作者:
J. Jonathan;Li;R. Charles;Ross;H. Tepperman;Jay;Tepperman
通讯作者:
Tepperman
影响因子:
3.9
作者:
Rao,JG;Harris,BG;Cook,PF
通讯作者:
Cook,PF
影响因子:
6.1
作者:
A. Howard;G. Gilliland;B. Finzel;T. Poulos;D. Ohlendorf;F. Salemme
通讯作者:
F. Salemme
影响因子:
1.3
作者:
H. J. Saz
通讯作者:
H. J. Saz
影响因子:
1.5
作者:
Allen,BL;Harris,BG
通讯作者:
Harris,BG