We have previously reported that a novel S-benzylisothiourea derivative, S-(3,4-dichlorobenzyl)isothiourea, tentatively named A22, induced spherical cells in Escherichia coli. To elucidate the structural element(s) required for inducing these spherical cells, the biological activity of S-benzylisothiourea derivatives and related compounds toward E. coli cells was investigated. S-(4-Chlorobenzyl)isothiourea revealed spherical cell-inducing activity, although being slightly less potent than A22, and S-benzylisothiourea itself showed much less activity. S-Cyclohexylmethylisothiourea did not show antibacterial activity and had little effect on the cell shape. S-Heptylisothiourea showed antibacterial activity and induced elongated cells rather than spherical cells. Benzylisothiocyanate inhibited cell growth but did not induce spherical cells. S-Ethylisothiourea, benzylthiocyanate, benzylisocyanate, and N-phenylthiourea did not show any activity under the present experimental conditions. These results indicate that the S-benzylisothiourea structure was necessary and sufficient for inducing spherical cells and that 3- and/or 4-chloro-substitution of the S-benzyl group enhanced this activity.
我们之前报道过一种新型的S-苄基异
硫脲衍
生物,即S-(3,4-二
氯苄基)异
硫脲,暂名为A22,能诱导大肠杆菌产生球状细胞。为了阐明诱导这些球状细胞所需的结构要素,我们对S-苄基异
硫脲衍
生物及相关化合物对大肠杆菌细胞的
生物活性进行了研究。S-(4-
氯苄基)异
硫脲显示出诱导球状细胞的活性,尽管其效力略低于A22,而S-苄基异
硫脲本身的活性则低得多。S-环己基甲基异
硫脲没有显示出抗菌活性,对细胞形态影响甚微。S-庚基异
硫脲表现出抗菌活性,并诱导细胞伸长而非球形化。苄基异
硫氰酸酯抑制细胞生长但未诱导出球状细胞。S-乙基异
硫脲、苄基
硫氰酸酯、苄基
异氰酸酯和N-苯基异
硫脲在当前实验条件下未显示出任何活性。这些结果表明,S-苄基异
硫脲结构对于诱导球状细胞既是必要的也是充分的,并且S-苄基上的3-和/或4-
氯取代增强了这种活性。