Baumann L, Baumann P, Moran N A
Microbiology Section, University of California, Davis, CA 95616-8665, USA.
Curr Microbiol. 1998 Jul;37(1):58-9. doi: 10.1007/s002849900337.
Previously it has been shown that the prokaryotic endosymbiont (Buchnera) of the aphid Diuraphis noxia contains a plasmid consisting of one copy of the gene for anthranilate synthase (trpEG) and seven trpEG pseudogenes. In the present communication we show that this endosymbiont contains the remaining genes of the tryptophan biosynthetic pathway [trpDC(F)BA] which appear to be functional in that they code for the complete enzyme proteins and are not pseudogenes. As in the case of Buchnera from other endosymbionts, these genes appear to be organized as one transcription unit and are located on the endosymbiont chromosome.
此前已有研究表明，麦二叉蚜的原核内共生菌（布赫纳氏菌）含有一个质粒，该质粒由一份邻氨基苯甲酸合酶基因（trpEG）和七个trpEG假基因组成。在本论文中，我们表明这种内共生菌含有色氨酸生物合成途径的其余基因[trpDC(F)BA]，这些基因似乎具有功能，因为它们编码完整的酶蛋白，而非假基因。与来自其他内共生菌的布赫纳氏菌情况一样，这些基因似乎被组织成一个转录单元，并位于内共生菌染色体上。
