A SINGLE AMINO-ACID SUBSTITUTION CHANGES THE SUBSTRATE-SPECIFICITY OF QUINOPROTEIN GLUCOSE-DEHYDROGENASE IN GLUCONOBACTER-OXYDANS
A SINGLE AMINO-ACID SUBSTITUTION CHANGES THE SUBSTRATE-SPECIFICITY OF QUINOPROTEIN GLUCOSE-DEHYDROGENASE IN GLUCONOBACTER-OXYDANS
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DOI：
10.1007/bf00272157
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发表时间：
1991-10-01
期刊：
影响因子：
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通讯作者：
GOOSEN, N
中科院分区：
文献类型：
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作者：
CLETONJANSEN, AM;DEKKER, S;GOOSEN, N
葡糖醛酸氧化酶含有吡咯并喹啉醌依赖性葡萄糖脱氢酶（GDH）。两个同基因G.氧化物菌株，P1和P2，其不同的底物特异性方面的糖的氧化进行了分析。P1只能氧化D-葡萄糖，而P2也能够氧化双糖麦芽糖。为了研究这种麦芽糖氧化特性的性质，我们从P2克隆了编码GDH的基因。P2 gdh在P1中的表达使后者菌株能够氧化麦芽糖，表明P2 gdh基因中的突变负责底物特异性的变化。该突变可归因于1bp的取代，导致His 787被Asn取代。
Gluconobacter oxydans contains pyrrolo-quinoline quinone-dependent glucose dehydrogenase (GDH). Two isogenic G. oxydans strains, P1 and P2, which differ in their substrate specificity with respect to oxidation of sugars have been analysed. P1 can oxidize only D-glucose, whereas P2 is also capable of the oxidation of the disaccharide maltose. To investigate the nature of this maltose-oxidizing property we cloned the gene encoding GDH from P2. Expression of P2 gdh in P1 enables the latter strain to oxidize maltose, indicating that a mutation in the P2 gdh gene is responsible for the change in substrate specificity. This mutation could be ascribed to a 1 bp substitution resulting in the replacement of His 787 by Asn.