Enzymatic and physico-chemical characteristics of recombinant cMDH and mMDH of Clonorchis sinensis.
The cytosol and mitochondrial malate dehydrogenases (MDHs, EC 1.1.1.37) of Clonorchis sinensis were expressed in Escherichia coli as a fusion protein with a 6xHis and GST tag, respectively. The cytosol MDH of Clonorchis sinensis (Cs-cMDH) has higher resistibility to acid than mitochondrial MDH (Cs-mMDH). The Cs-cMDH also has higher heat resistibility and thermal stability than Cs-mMDH. Although there is only 22.8% identity between the amino acid sequences of Cs-cMDH and Cs-mMDH, they share several conserved residues. There are some differences between the circular dichroism spectra of Cs-cMDH and Cs-mMDH, but they have approximate percentages of helix. 4,4'-Bisdimethylamino diphenylcarbinol can decrease the Cs-mMDH activity but not the Cs-cMDH activity. Paraziquantel, metronidazole and albendazole did not inhibit the enzymes' activity, but adenosine 5'-monophosphate showed competitive inhibition to enzyme, with the Ki for Cs-cMDH and Cs-mMDH being 2.81 and 0.49 mM, respectively.
Zheng
Nancai
N
Center for Disease Control and Prevention of Jiangmen City, Jiangmen, 529020, Guangdong Province, People's Republic of China.
Huang
Baoming
B
Xu
Jin
J
Huang
Shansheng
S
Chen
Jinzhong
J
Hu
Xuchu
X
Ying
Kang
K
Yu
Xinbing
X
D000595:Amino Acid Sequence; D000818:Animals; D002942:Circular Dichroism; D003004:Clonorchis sinensis / Q000201:enzymology* / Q000235:genetics; D003600:Cytosol / Q000201:enzymology*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015801:Helminth Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008291:Malate Dehydrogenase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D013696:Temperature
D015801:Helminth Proteins; D011993:Recombinant Fusion Proteins; D008291:Malate Dehydrogenase