Tajima Y
Clinical Laboratory, Saga Medical School Hospital, Nabeshima, Japan.
Biol Pharm Bull. 2001 Sep;24(9):1079-84. doi: 10.1248/bpb.24.1079.
Some Keggin-structural (hetero)polyoxotungstates with a lacunary hole, such as undecatungstosilicate ([SiW11O39]8-, SiW11), greatly sensitize methicillin-resistant Staphylococcus aureus (MRSA) to beta-lactams. In this study, the effects of lacunary-substituted derivatives of SiW11 were tested to determine if the lacunary hole is required for the sensitizing effect. Initially, it was supposed that the hole functioned as a binding site that interacts with some bacterial components. However, most of the lacunary-substituted species had stronger effects than SiW11, indicating that the hole is not essential for the sensitizing effect. Undecatungsto(ferri)ferrosilicate (SiW11O39Fe) was the most potent compound tested, but undecatungstocobaltosilicate ([SiW11O39Co]6-) gave better results according to the fractional inhibitory concentration index. Small lipophilic cations enhanced the sensitizing effect, but bulky cations inhibited it. This suggests that a charge interaction between the tungsten compounds and some unknown materials in the culture medium or bacterial cells plays an important role in the sensitizing effect.
一些具有空位孔的Keggin结构（杂）多氧钨酸盐，如十一钨硅酸根离子（[SiW11O39]8-，SiW11），能极大地增强耐甲氧西林金黄色葡萄球菌（MRSA）对β-内酰胺类药物的敏感性。在本研究中，测试了SiW11的空位取代衍生物的效果，以确定空位孔对于致敏作用是否必要。最初，人们认为该孔作为一个与某些细菌成分相互作用的结合位点。然而，大多数空位取代物种比SiW11具有更强的效果，这表明该孔对于致敏作用并非必不可少。十一钨铁（III）硅酸根离子（SiW11O39Fe）是测试的最有效的化合物，但根据分数抑制浓度指数，十一钨钴硅酸根离子（[SiW11O39Co]6-）效果更好。小的亲脂性阳离子增强了致敏作用，但体积大的阳离子则抑制了它。这表明钨化合物与培养基或细菌细胞中某些未知物质之间的电荷相互作用在致敏作用中起重要作用。
