Pickard M A
Can J Biochem. 1980 Jun;58(6):457-60. doi: 10.1139/o80-060.
Nucleoside entry into isolated membrane vesicles of Micrococcus sodonensis (luteus) was studied using 14C-labelled nucleosides: adenosine, inosine, cytidine, uridine, guanosine, and thymidine. All nucleosides were recovered unmetabolized from the vesicles except adenosine and cytidine which were partly deaminated by membrane-bound enzymes. Vesicle preparations actively transported proline but no energy source was found capable of supporting concentrative nucleoside uptake. The entry of nucleosides into M. sodonensis vesicles was not saturable, nor was there competition between the nucleosides studied for entry. It was concluded that nucleoside entry into M. sodonensis vesicles occurs by passive diffusion.
利用14C标记的核苷：腺苷、肌苷、胞苷、尿苷、鸟苷和胸苷，研究了核苷进入嗜钠微球菌（藤黄微球菌）分离的膜泡的过程。除腺苷和胞苷被膜结合酶部分脱氨外，所有核苷均未代谢地从膜泡中回收。膜泡制剂能主动转运脯氨酸，但未发现有能量源能够支持核苷的浓缩摄取。核苷进入嗜钠微球菌膜泡的过程不饱和，所研究的核苷之间也不存在进入竞争。得出的结论是，核苷进入嗜钠微球菌膜泡是通过被动扩散发生的。
