Haffter P, Bickle T A
Department of Microbiology, University of Basel, Switzerland.
J Mol Biol. 1987 Dec 20;198(4):579-87. doi: 10.1016/0022-2836(87)90201-4.
An Escherichia coli chromosomally coded factor termed FIS (Factor for Inversion Stimulation) stimulates the Cin protein-mediated, site-specific DNA inversion system of bacteriophage P1 more than 500-fold. We have purified FIS and the recombinase Cin, and studied the inversion reaction in vitro. DNA footprinting studies with DNase I showed that Cin specifically binds to the recombination site, called cix. FIS does not bind to cix sites but does bind to a recombinational enhancer sequence that is required in cis for efficient recombination. FIS also binds specifically to sequences outside the enhancer, as well as to sequences unrelated to Cin inversion. On the basis of these data, we discuss the possibility of additional functions for FIS in E. coli.
一种由大肠杆菌染色体编码的名为FIS（反转刺激因子）的因子，能将噬菌体P1的Cin蛋白介导的位点特异性DNA反转系统刺激500多倍。我们已经纯化了FIS和重组酶Cin，并在体外研究了反转反应。用DNase I进行的DNA足迹研究表明，Cin特异性结合到称为cix的重组位点。FIS不结合cix位点，但确实结合到顺式作用的高效重组所需的重组增强子序列。FIS还特异性结合增强子以外的序列，以及与Cin反转无关的序列。基于这些数据，我们讨论了FIS在大肠杆菌中具有其他功能的可能性。
