Thomas C E, Sparling P F
Department of Microbiology, School of Medicine, University of North Carolina at Chapel Hill, 27599, USA.
J Bacteriol. 1996 Jul;178(14):4224-32. doi: 10.1128/jb.178.14.4224-4232.1996.
The pathogenic Neisseria spp. produce a number of iron-regulated gene products that are thought to be important in virulence. Iron-responsive regulation of these gene products has been attributed to the presence in Neisseria spp. of the Fur (ferric uptake regulation) protein. Evidence for the role of Fur in neisserial iron regulation has been indirect because of the inability to make fur null mutations. To circumvent this problem, we used manganese selection to isolate missense mutations of Neisseria gonorrhoeae fur. We show that a mutation in gonococcal fur resulted in reduced modulation of expression of four well-studied iron-repressed genes and affected the iron regulation of a broad range of other genes as judged by two-dimensional polyacrylamide gel electrophoresis (PAGE). All 15 of the iron-repressed spots observed by two-dimensional PAGE were at least partially derepressed in the fur mutant, and 17 of the 45 iron-induced spots were affected by the fur mutation. Thus, Fur plays a central role in regulation of iron-repressed gonococcal genes and appears to be involved in regulation of many iron-induced genes. The size and complexity of the iron regulons in N. gonorrhoeae are much greater than previously recognized.
致病性奈瑟菌属产生多种铁调节基因产物，这些产物被认为在毒力方面很重要。这些基因产物的铁应答调节归因于奈瑟菌属中存在Fur（铁摄取调节）蛋白。由于无法产生fur无效突变，Fur在奈瑟菌铁调节中的作用证据一直是间接的。为了解决这个问题，我们利用锰选择来分离淋病奈瑟菌fur的错义突变。我们发现淋病奈瑟菌fur中的一个突变导致四个经过充分研究的铁抑制基因的表达调节降低，并通过二维聚丙烯酰胺凝胶电泳（PAGE）判断，影响了广泛的其他基因的铁调节。二维PAGE观察到的所有15个铁抑制斑点在fur突变体中至少部分去抑制，45个铁诱导斑点中的17个受到fur突变的影响。因此，Fur在铁抑制的淋病奈瑟菌基因调节中起核心作用，并且似乎参与了许多铁诱导基因的调节。淋病奈瑟菌中铁调节子的大小和复杂性比以前认识的要大得多。
