Sojka Ludĕk, Fucík Vladimír, Krásný Libor, Barvík Ivan, Jonák Jirí
Institute of Molecular Genetics ASCR, Vídenská 1083, 142 20 Prague 4, Czech Republic.
J Bacteriol. 2007 Jul;189(13):4809-14. doi: 10.1128/JB.01786-06. Epub 2007 Apr 27.
The ybxF gene is a member of the streptomycin operon in a wide range of gram-positive bacteria. In Bacillus subtilis, it codes for a small basic protein (82 amino acids, pI 9.51) of unknown function. We demonstrate that, in B. subtilis, YbxF localizes to the ribosome, primarily to the 50S subunit, with dependence on growth phase. Based on three-dimensional structures of YbxF generated by homology modeling, we identified helix 2 as important for the interaction with the ribosome. Subsequent mutational analysis of helix 2 revealed Lys24 as crucial for the interaction. Neither the B. subtilis ybxF gene nor its paralogue, the ymxC gene, is essential, as shown by probing DeltaybxF, DeltaymxC, or DeltaybxF DeltaymxC double deletion strains in several functional assays.
ybxF基因是多种革兰氏阳性细菌中链霉素操纵子的一个成员。在枯草芽孢杆菌中,它编码一种功能未知的小碱性蛋白(82个氨基酸,pI 9.51)。我们证明,在枯草芽孢杆菌中,YbxF定位于核糖体,主要定位于50S亚基,且依赖于生长阶段。基于同源建模生成的YbxF三维结构,我们确定螺旋2对于与核糖体的相互作用很重要。随后对螺旋2的突变分析表明赖氨酸24对于这种相互作用至关重要。在几种功能测定中对ΔybxF、ΔymxC或ΔybxF ΔymxC双缺失菌株进行检测,结果表明枯草芽孢杆菌的ybxF基因及其旁系同源基因ymxC都不是必需的。