Studies on <beta> -hemolysin toxin of Streptococcus faecalis

粪链球菌产生的溶血素已被证明有助于小鼠的毒力。对日本97株粪链球菌临床分离株的溶血素产生、凝集（信息素）反应、溶血性状的可转移性、溶血质粒的结构和耐药性进行了检测。尿、脓、阴道、痰、胆汁和血液），并且发现大约60%是溶血性的。与约49%的非溶血性菌株相比，约85%的溶血性菌株表现出凝集反应。超过50%的溶血性菌株携带可转移的溶血素决定簇，并且在任何情况下都没有与耐药基因相关。溶血性菌株比非溶血性菌株表现出更频繁的多重耐药。溶血素-细菌素质粒pAD 1（56.7kb）分离自密歇根州的安阿伯，是粪链球菌中分析良好的接合质粒之一。在本研究中，发现11个可转移的cAD 1应答质粒在结构上类似于（限制性片段）pAD 1。

Hemolysin produced by Streptococcus faecalis has been shown to contribute to virulence in mice. Hemolysin production, clumping (pheromone) response, transferability of the hemolytic trait, structure of the hemolytic plasmid, and drug resistance were examined in 97 clinical isolates of S.faecalis in Japan.The isolates were derived from various sources (i.e., urine, pus, vaginal, sputum, bile and blood), and approximately 60% were found to be hemolytic. About 85% of the hemolytic strains exhibited a clumping response compared to about 49% of the non-hemolytic strains. Over 50% of the hemolytic strains carried transferable hemolysin determinants, and in no case were drug-resistance genes linked. The hemolytic strains exhibited multiple drug-resistance more frequently than the non-hemolytic strains. In contrast to the high frequency of hemolysin producers among parenteral isolates, strains derived from fecal specimens of healthy individuals exhibited a low (17%) incidence of hemolysin production.Hemolysin-bacteriocin plasmid pAD1(56.7kb), isolated in Ann Arbor, MI, is one of the well analyzed conjugative plasmids in S.faecalis. Eleven transferable cAD1-responding plasmids in the present study were found to structurally resemble (restriction fragments) pAD1.