de Meester C, Rondelet J
Pathol Biol (Paris). 1977 Dec;25(10):685-9.
Virginiamycin M factor transformation into an o-acetyl derivative has been observed in a particular Staphylococcus strain, naturally resistant to virginiamycin (Vr). It could not be detected in induced strains nor in sensitive ones. Turbidimetric studies with the naturally resistant strain showed that increasing concentration of the antibiotic had a progressive prolongation effect on the lag phase, without change in the growth rate. The prolonged lag phase could be reduced or eliminated by using an inoculum of cells previously "adapted" to M factor or virginiamycin. Preadapted cells had an increased acetylating power. Acridine dye treated cells showed a decreased o-acetyl derivative formation. This all suggested that virginiamycin resistance in the particular Vr strain was effectively connected with o-acetylation of the M factor.
在一株对维吉尼亚霉素（Vr）天然耐药的特定葡萄球菌菌株中，观察到维吉尼亚霉素M因子转化为邻乙酰基衍生物。在诱导菌株和敏感菌株中均未检测到这种转化。对该天然耐药菌株进行的比浊法研究表明，抗生素浓度增加对延滞期有逐渐延长的作用，而生长速率不变。通过使用先前“适应”于M因子或维吉尼亚霉素的细胞接种物，可以减少或消除延长的延滞期。预先适应的细胞具有增强的乙酰化能力。吖啶染料处理的细胞显示邻乙酰基衍生物的形成减少。这一切表明，特定Vr菌株中的维吉尼亚霉素耐药性与M因子的邻乙酰化有效相关。
