中文摘要：

P-环NTP酶（GTP酶和ATP酶）普遍存在于真核生物和原核生物中,参与调节不同的细胞进程.Ych F和Yih A是细菌中两种高度保守的NTP酶,但其生理功能仍然不清楚.之前的研究表明这两种NTP酶可以与核糖体或者核糖体亚基结合.我们检测了在不同核苷酸存在的情况下,大肠杆菌Y ch F和Yih A蛋白与核糖体30S、50S、70S颗粒的结合情况,同时也探究了核糖体亚基的结合是否与N TP酶活性的激活有关.数据表明Ych F与70S结合,Yih A与50S结合.70S核糖体能同时激活Y ch F的ATP酶和GTP酶活性.然而Yih A的GTP酶活性可以分别被50S和70S激活,并且70S呈现了8.8倍的激活效应.这些数据为进一步研究这两种保守的NTPase的生理功能奠定了基础.

英文摘要：

P-loop NTPases（GTPase and ATPase） are widely employed in both prokaryotes and eukaryotes to regulate various cellular processes. Ych F and Yih A are two highly conserved NTPases in bacteria, but their cellular roles remain elusive. Previous data revealed that the ribosome or ribosomal subunits are binding partners of these two NTPases. Here, we examined the binding preferences of Escherichia coli Ych F and Yih A to the 30 S, 50 S and 70 S ribosomes in the presence of different nucleotides, and assayed whether these binding preferences were associated with the stimulation of their NTPase activities. Our data show that Ych F and Yih A display a strong preference for the 70 S and 50 S, respectively. While the 70 S ribosome, but not the 50 S or 30 S, promotes both the ATPase and GTPase activities of Ych F, Yih A responds to both the 50 S and 70 S, with the moderate GTPase stimulation（～8.8 fold） seen in the presence of the 70S ribosome.