Waldbeser L S, Tolmasky M E, Actis L A, Crosa J H
Department of Microbiology and Immunology, School of Medicine, Oregon Health Sciences University, Portland 97201-3098.
J Biol Chem. 1993 May 15;268(14):10433-9.
Synthesis of the 86-kDa FatA outer membrane protein is repressed under iron-rich conditions. Complementation of transposition mutants derived from clones containing the pJM1 iron uptake region revealed the existence of an antisense RNA, RNA alpha. This RNA is only expressed under iron-rich conditions and acts as a negative regulator of FatA synthesis, with slight but discernible decrease in the steady-state level of fatA mRNA determined by RNase protection and by Northern blot analysis. Primer extension experiments revealed that the level of several possible fatA transcripts was reduced in the presence of RNA alpha. In addition, we found that fatA mRNA expression is slightly reduced in the presence of Escherichia coli Fur. We have identified and cloned a chromosomally encoded fur-like gene in Vibrio anguillarum.
86 kDa FatA外膜蛋白的合成在富铁条件下受到抑制。对源自含有pJM1铁摄取区域的克隆的转座突变体进行互补分析，揭示了一种反义RNA，即RNAα的存在。这种RNA仅在富铁条件下表达，并作为FatA合成的负调节因子，通过核糖核酸酶保护和Northern印迹分析确定，fatA mRNA的稳态水平略有但可察觉的下降。引物延伸实验表明，在RNAα存在的情况下，几种可能的fatA转录本水平降低。此外，我们发现，在大肠杆菌Fur存在的情况下，fatA mRNA表达略有降低。我们已经在鳗弧菌中鉴定并克隆了一个染色体编码的类fur基因。
