저자(한글) |
Wang, Liangliang,Wang, Jiajun,Shi, Hao,Gu, Huaxiang,Zhang, Yu,Li, Xun,Wang, Fei |
저자(영문) |
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소속기관 |
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소속기관(영문) |
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출판인 |
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간행물 번호 |
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발행연도 |
2016-01-01 |
초록 |
Glycerol dehydrogenases (GlyDHs) are essential for glycerol metabolism in vivo, catalyzing its reversible reduction to 1,3-dihydroxypropranone (DHA). The gldA gene encoding a putative GlyDH was cloned from Thermoanaerobacterium thermosaccharolyticum DSM 571 (TtGlyDH) and expressed in Escherichia coli. The presence of Mn 2+ enhanced its enzymatic activity by 79.5%. Three highly conserved residues (Asp 171 , His 254 , and His 271 ) in TtGlyDH were associated with metal ion binding. Based on an investigation of glycerol oxidation and DHA reduction, TtGlyDH showed maximum activity towards glycerol at 60 #8451; and pH 8.0 and towards DHA at 60 #8451; and pH 6.0. DHA reduction was the dominant reaction, with a lower K m(DHA) of 1.08 #xb1; 0.13 mM and V max of 0.0053 #xb1; 0.0001 mM/s, compared with glycerol oxidation, with a K m(glycerol) of 30.29 #xb1; 3.42 mM and V max of 0.042 #xb1; 0.002 mM/s. TtGlyDH had an apparent activation energy of 312.94 kJ/mol. The recombinant TtGlyDH was thermostable, maintaining 65% of its activity after a 2-h incubation at 60 #8451;. Molecular modeling and site-directed mutagenesis analyses demonstrated that TtGlyDH had an atypical dinucleotide binding motif (GGG motif) and a basic residue Arg 43 , both related to dinucleotide binding. |
원문URL |
http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=03553784&target=NART&cn=JAKO201620836761818 |
첨부파일 |
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