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.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 在真核生物中，参与将 UDP-GlcA 转化为其他 UDP-糖的酶已被充分描述，但在原核生物中却知之甚少。在这里，我们鉴定并表征了来自 Ralstonia solanacearum str. 的基因 (RsU4kpxs)。 GMI1000，编码双功能酶 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-threo-pentopyranosyl-4"-ulose (UDP-4-keto-pentose)。第二种活性是将 UDP-4-keto-pentose 和 NADH 转化为 UDP-木糖和 NAD+，尽管转化率较低。青枯菌酶的鉴定 使我们能够提出，祖先的 UXS（以及 UDP-apiose 合酶或 UAXS）在早期细菌中分化为两种不同的酶活性。这种分离产生了目前动物、真菌和植物中的 Uxs 以及植物 Uaxs 同源物。