Mori M, Sakagami Y, Ishii Y, Isogai A, Kitada C, Fujino M, Adsit J C, Dunny G M, Suzuki A
Department of Agricultural Chemistry, University of Tokyo, Japan.
J Biol Chem. 1988 Oct 5;263(28):14574-8.
The peptide pheromone, cCF10, which induces aggregation and high frequency plasmid transfer in Streptococcus faecalis cells carrying the tetracycline resistance plasmid, pCF10, was isolated and its structure determined. The molecular weight of cCF10 is 789, and its amino acid sequence is H-Leu-Val-Thr-Leu-Val-Phe-Val-OH. Pheromone activity, as determined by a clumping induction assay, was detectable at a concentration of 2.5 x 10(-11) M. A peptide of the same sequence as that of the cCF10 produced by S. faecalis cells was synthesized by the liquid-phase method. The synthetic pheromone showed biological activity and chromatographic behavior that was identical to that of the cCF10 of bacterial origin. When the response of S. faecalis cells to various concentrations of synthetic cCF10 was monitored by measuring both the frequency of plasmid transfer and the synthesis of pheromone-inducible antigens, an excellent correlation was observed between donor ability and the appearance of a 150-kilodalton protein that appears to be involved in formation of mating aggregates. The dose-response data in the range of concentrations where the amount of pheromone became limiting (10(-11)-10(-12) M) were consistent with the notion that as few as one or two molecules per donor cell may be sufficient to induce a mating response.
在携带四环素抗性质粒pCF10的粪肠球菌细胞中诱导聚集和高频质粒转移的肽信息素cCF10已被分离并确定其结构。cCF10的分子量为789，其氨基酸序列为H-Leu-Val-Thr-Leu-Val-Phe-Val-OH。通过凝集诱导试验测定，在浓度为2.5×10(-11)M时可检测到信息素活性。采用液相法合成了与粪肠球菌细胞产生的cCF10序列相同的肽。合成的信息素表现出与细菌来源的cCF10相同的生物学活性和色谱行为。当通过测量质粒转移频率和信息素诱导抗原的合成来监测粪肠球菌细胞对各种浓度合成cCF10的反应时，在供体能力与一种似乎参与交配聚集体形成的150千道尔顿蛋白质的出现之间观察到了极好的相关性。在信息素量变得有限的浓度范围内（10(-11)-10(-12)M）的剂量反应数据与每个供体细胞中低至一两个分子可能足以诱导交配反应的观点一致。
