结核分枝杆菌中尿嘧啶磷酸核糖转移酶表达的分析及感染小鼠中upp基因敲除菌株的评估。

Analysis of uracil phosphoribosyltransferase expression in Mycobacterium tuberculosis and evaluation of upp knockout strain in infected mice.

作者信息

Villela Anne Drumond, Pham Ha, Jones Victoria, Grzegorzewicz Anna E, Rodrigues-Junior Valnês da Silva, Campos Maria Martha, Basso Luiz Augusto, Jackson Mary, Santos Diógenes Santiago

机构信息

National Institute of Science and Technology in Tuberculosis, Research Center in Molecular and Functional Biology, Pontifical Catholic University of Rio Grande do Sul-PUCRS, CEP 90619-900, Porto Alegre, RS, Brazil.

Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523 USA.

出版信息

FEMS Microbiol Lett. 2017 Feb 1;364(4). doi: 10.1093/femsle/fnx023.

DOI:10.1093/femsle/fnx023

PMID:28130366

Abstract

The upp (Rv3309c)-encoded uracil phosphoribosyltransferase from Mycobacterium tuberculosis (MtUPRT) converts uracil and 5-phosphoribosyl-α-1-pyrophosphate into pyrophosphate and uridine 5΄-monophosphate, the precursor of all pyrimidine nucleotides. A M. tuberculosis knockout strain for upp gene was generated by allelic replacement. Knockout and complemented strains were validated by a functional assay of uracil incorporation. A basal level of MtUPRT expression is shown to be independent of either growth medium used, addition of bases, or oxygen presence/absence. The upp disruption does not affect M. tuberculosis growth in Middlebrook 7H9 medium, and it is not required for M. tuberculosis virulence in a mouse model of infection. Thus, MtUPRT is unlikely to be a good target for drugs against M. tuberculosis.

摘要

来自结核分枝杆菌的upp（Rv3309c）编码的尿嘧啶磷酸核糖转移酶（MtUPRT）将尿嘧啶和5-磷酸核糖-α-1-焦磷酸转化为焦磷酸和尿苷5′-单磷酸，后者是所有嘧啶核苷酸的前体。通过等位基因置换构建了upp基因的结核分枝杆菌敲除菌株。通过尿嘧啶掺入功能测定对敲除菌株和互补菌株进行了验证。结果表明，MtUPRT的基础表达水平与所使用的生长培养基、碱基添加或氧气存在与否无关。upp基因的破坏不影响结核分枝杆菌在Middlebrook 7H9培养基中的生长，并且在小鼠感染模型中，它对于结核分枝杆菌的毒力并非必需。因此，MtUPRT不太可能成为抗结核分枝杆菌药物的理想靶点。