...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >Characterization of the RokA and HexA Broad-Substrate-Specificity Hexokinases from Bacteroides fragilis and Their Role in Hexose and N-Acetylglucosamine Utilization
【24h】

Characterization of the RokA and HexA Broad-Substrate-Specificity Hexokinases from Bacteroides fragilis and Their Role in Hexose and N-Acetylglucosamine Utilization

机译：脆弱拟杆菌的RokA和HexA广泛底物特异性己糖激酶的表征及其在己糖和N-乙酰氨基葡萄糖利用中的作用

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Bacteroides fragilis, a human gastrointestinal commensal and an opportunistic pathogen, utilizes simple and complex sugars and polysaccharides for growth in the large intestine and at sites of infection. Because B. fragilis lacks transport-linked sugar phosphorylation systems, cytoplasmic kinase(s) was expected to be required for the phosphorylation of hexoses and hexosamines. We have now identified two hexose kinases that are important for growth of B. fragilis on glucose, mannose, and other sugars. One kinase (RokA), a member of the ROK family of proteins, was found to be the sole kinase for activation of N-acetyl-d-glucosamine (NAG). The other kinase (HexA) is responsible for the majority of the glucose kinase activity in the cell, although a hexA deletion mutant strain was not defective for growth on any substrate tested. Deletion of both the rokA and hexA kinase genes resulted in inability of the cell to use glucose, mannose, NAG, and many other sugars. We purified RokA and determined its approximate molecular mass to be 36.5 kDa. The purified RokA protein was shown to phosphorylate several substrates, including glucose, NAG, and mannose, but not N-acetylmannosamine or N-acetylneuraminic acid. Phylogenetic analysis of RokA showed that it is most similar to kinases from the Cytophaga-Flavibacterium-Bacteroides group, while HexA was most similar to other bacterial hexokinases and eukaryotic hexokinases.
机译：脆弱的拟杆菌（Bacteroides fragilis）是人类胃肠道疾病和机会病原体，它利用简单和复杂的糖和多糖在大肠和感染部位生长。因为 B。脆弱类植物缺乏运输相关的糖磷酸化系统，预计己糖和己糖胺的磷酸化需要胞质激酶。现在我们已经确定了两个对B的生长很重要的己糖激酶。易碎的葡萄糖，甘露糖和其他糖。发现一种激酶（RokA）是ROK蛋白质家族的成员，是激活 N -乙酰基-d-葡萄糖胺（NAG）的唯一激酶。另一个激酶（HexA）负责细胞中大部分的葡萄糖激酶活性，尽管 hexA 缺失突变株在任何测试的底物上均无缺陷。 rokA 和 hexA 激酶基因的缺失导致细胞无法使用葡萄糖，甘露糖，NAG和许多其他糖。我们纯化了RokA，并确定其近似分子量为36.5 kDa。纯化的RokA蛋白被证明可以磷酸化几种底物，包括葡萄糖，NAG和甘露糖，而不能 N -乙酰甘露糖胺或 N -乙酰神经氨酸。 RokA的系统发育分析表明，它与<噬菌丝藻-黄杆菌-拟杆菌组的激酶最相似，而HexA与其他细菌己糖激酶和真核己糖激酶最相似。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号