APPLICATION OF NMR TO THE STUDY OF XYLOSE SYNTHASES

核磁共振在木糖合酶研究中的应用

• 批准号: 8168895
• 负责人: JOHN GLUSHKA
• 金额: $ 0.17万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-10 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8168895
• 关键词: Animals; Bacteria; Computer Retrieval of Information on Scientific Projects Database; Enzymes; Eukaryota; Funding; Genes; Grant; Homologous Gene; Institution; NADH; Pentoses; Plants; Prokaryotic Cells; Ralstonia solanacearum; Research; Research Personnel; Resources; Source; United States National Institutes of Health; Uridine Diphosphate Glucuronic Acid; Uridine Diphosphate Sugars; Uridine Diphosphate Xylose; Xylose; apiose; plant fungi

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The enzymes involved in converting UDP-GlcA to other UDP-sugars are well described in eukaryotes, but less is known in prokaryotes. Here we identify and characterize a gene (RsU4kpxs) from Ralstonia solanacearum str. GMI1000, which encodes a dual-function enzyme, UDP-4-keto-pentose/UDP-xylose synthase (UXS). One activity is to decarboxylate UDP-glucuronic acid to UDP-¿-L-threo-pentopyranosyl-4"-ulose (UDP-4-keto-pentose) in the presence of NAD+. The second converts UDP-4-keto-pentose and NADH to UDP-xylose and NAD+, albeit at a lower rate. The identification of the R. solanacearum enzyme enables us to propose that the ancestral UXS (as well as UDP-apiose synthase or UAXS) diverged into two distinct enzymatic activities in early bacteria. This separation gave rise to the current Uxs in animal, fungus and plant as well as to the plant Uaxs homologs.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 参与将UDP-GlcA转化为其他UDP-糖的酶在真核生物中有很好的描述，但在原核生物中知之甚少。在这里，我们确定和表征的基因（RsU 4kpxs）从青枯雷尔氏菌str.GMI1000，它编码的双功能酶，UDP-4-酮戊糖/UDP-木糖合酶（UXS）。一种活性是在NAD+存在下将UDP-葡萄糖醛酸脱羧为UDP-<$-L-苏型-吡喃戊糖基-4”-酮糖（UDP-4-酮-戊糖）。第二个将UDP-4-酮戊糖和NADH转化为UDP-木糖和NAD+，尽管速率较低。对该菌的鉴定进行了研究。青枯菌酶使我们能够提出祖先UXS（以及UDP-芹菜糖合酶或UAXS）在早期细菌中分化成两种不同的酶活性。这种分离产生了目前在动物、真菌和植物中的Uxs以及植物Uaxs同系物。