Identification and characterization of 2-keto-3-deoxygluconate kinase and 2-keto-3-deoxygalactonate kinase in the haloarchaeon Haloferax volcanii.
Identification and characterization of 2-keto-3-deoxygluconate kinase and 2-keto-3-deoxygalactonate kinase in the haloarchaeon Haloferax volcanii.
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盐古菌 Haloferax volcanii 中 2-酮-3-脱氧葡萄糖酸激酶和 2-酮-3-脱氧半乳糖酸激酶的鉴定和表征
DOI：
10.1111/1574-6968.12617
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发表时间：
2014
影响因子：
2.1
通讯作者：
Schönheit
中科院分区：
文献类型：
--
作者：
Johnsen;Archer;Schönheit
嗜盐古菌Haloferax volcanii通过半磷酸化Entner-Doudoroff途径降解葡萄糖，其中2-酮基-3-脱氧葡萄糖酸激酶（KDGK）是关键酶。到目前为止，既没有酶的特点，也没有编码基因已被确定。在H. volcanii中，两个基因HVO_0549（kdgK 1）和HVO_A0328（kdgK 2）被注释为编码推定的KDGK-1和KDGK-2。为了确定这两种激酶的生理作用，在不同的糖上进行两种基因的转录调控分析和相应缺失突变体的生长实验。此外，对重组KDGK-1和KDGK-2进行了表征。总之，数据表明KDGK-1代表葡萄糖降解中功能性组成型表达的KDG激酶，而KDGK-2是一种可诱导的2-酮-3-脱氧半乳糖酸激酶，可能与吲哚-半乳糖酶有关。本文描述了KDGK-1作为葡萄糖降解的半磷酸化艾德途径中的功能性2-酮-3-脱氧葡萄糖酸激酶的鉴定，以及KDGK-2作为2-酮-3-脱氧葡萄糖酸激酶的鉴定。脱氧半乳糖酸激酶在H.火山这两种酶都属于PFK（phosphofructokinase）-B家族的碳水化合物激酶，本文描述了KDGK-1作为半磷酸化艾德途径中葡萄糖降解的功能性2-酮-3-脱氧葡萄糖酸激酶和KDGK-2作为半乳糖降解的2-酮-3-脱氧半乳糖酸激酶在H.火山这两种酶都属于PFK（磷酸果糖激酶）-B家族的碳水化合物激酶。
The halophilic archaeonHaloferax volcaniihas been proposed to degrade glucose via the semi-phosphorylative Entner–Doudoroff pathway, involving 2-keto-3-deoxygluconate kinase (KDGK) as key enzyme. So far, neither the enzyme has been characterized nor the encoding gene has been identified. In the genome ofH. volcanii,two genes, HVO_0549 (kdgK1) and HVO_A0328 (kdgK2), are annotated encoding putative KDGK-1 and KDGK-2. To identify the physiological role of both kinases, transcriptional regulation analyses of both genes and growth experiments of the respective deletion mutants were performed on different sugars. Further, recombinant KDGK-1 and KDGK-2 were characterized. Together, the data indicate that KDGK-1 represents the functional constitutively expressed KDG kinase in glucose degradation, whereas KDGK-2 is an inducible 2-keto-3-deoxygalactonate kinase likely involved ind-galactose catabolism.The paper describes the identification of KDGK-1 as functional 2-keto-3-deoxygluconate kinase in the semi-phosphorylative ED pathway of glucose degradation and of KDGK-2 as 2-keto-3-deoxygalactonate kinase in galactose degradation inH. volcanii. Both enzymes belong to the PFK (phosphofructokinase)-B family of carbohydrate kinases.The paper describes the identification of KDGK-1 as functional 2-keto-3-deoxygluconate kinase in the semi-phosphorylative ED pathway of glucose degradation and of KDGK-2 as 2-keto-3-deoxygalactonate kinase in galactose degradation inH. volcanii. Both enzymes belong to the PFK (phosphofructokinase)-B family of carbohydrate kinases.