L-Aspartate oxidase is present in the anaerobic hyperthermophilic archaeon Pyrococcus horikoshii OT-3: characteristics and role in the de novo biosynthesis of nicotinamide adenine dinucleotide proposed by genome sequencing
L-Aspartate oxidase is present in the anaerobic hyperthermophilic archaeon Pyrococcus horikoshii OT-3: characteristics and role in the de novo biosynthesis of nicotinamide adenine dinucleotide proposed by genome sequencing
复制标题
L-天冬氨酸氧化酶存在于厌氧超嗜热古菌Pyrococcus horikoshii OT-3中：基因组测序提出的烟酰胺腺嘌呤二核苷酸从头生物合成的特征和作用
作者：
H. Sakuraba;T. Satomura;R. Kawakami;Sanae Yamamoto;Y. Kawarabayasi;H. Kikuchi;T. Ohshima
编码L-天冬氨酸氧化酶同源物的基因通过基因组测序在厌氧超嗜热古菌Pyrococcus horikoshii OT-3中鉴定。我们成功地在大肠杆菌中表达了编码基因，并纯化了产物。该蛋白质的表征表明，它是迄今为止检测到的最耐热的L-天冬氨酸氧化酶。除了氧化酶的活性，酶催化L-天冬氨酸脱氢的人工电子受体，如吩嗪硫酸甲酯，2，6-二氯苯酚-靛酚，和铁氰化物的存在下。L-天冬氨酸氧化酶是原核生物NAD从头合成途径中的第一个酶。通过在公共数据库中的相似性搜索，在堀越氏拟杆菌OT-3基因组中鉴定了编码参与该途径的所有其他酶的同源物的基因。这表明，堀越伪囊霉OT-3可能在厌氧条件下使用从头NAD生物合成途径。
A gene encoding the L-aspartate oxidase homologue was identified via genome sequencing in the anaerobic hyperthermophilic archaeon Pyrococcus horikoshii OT-3. We succeeded in expressing the encoding gene in Escherichia coli and purified the product to homogeneity. Characterization of the protein revealed that it is the most thermostable L-aspartate oxidase detected so far. In addition to the oxidase activity, the enzyme catalyzed L-aspartate dehydrogenation in the presence of an artificial electron acceptor such as phenazine methosulfate, 2,6-dichlorophenol-indophenol, and ferricyanide. L-Aspartate oxidase is known to function as the first enzyme in the de novo NAD biosynthetic pathway in prokaryotes. By a similarity search in public databases, the genes that encode the homologue of all other enzymes involved in the pathway were identified in the P. horikoshii OT-3 genome. This suggests that P. horikoshii OT-3 may use the de novo NAD biosynthetic pathway under anaerobic conditions.
铜绿假单胞菌中 algT 和 nadB 的遗传连锁：nadB 的突变不会影响 NAD 生物合成或藻酸盐生产。
影响因子：
3.5
作者：
DeVries,CA;Hassett,DJ;Flynn,JL;Ohman,DE
通讯作者：
Ohman,DE