Institut Pasteur, Unité Prévention et Thérapies Moléculaires des Maladies Humaines, Centre National de Référence des Corynébactéries du Complexe Diphtheriae, Paris, France; CNRS-URA 3012, Paris, France.
Clin Microbiol Infect. 2013 Oct;19(10):980-7. doi: 10.1111/1469-0691.12103. Epub 2013 Jan 15.
Autochtonous toxigenic Corynebacterium diphtheriae have disappeared in mainland France, but non-toxigenic C. diphtheriae are still circulating. Using phenotypic and molecular tools, we retrospectively characterized 103 non-toxigenic C. diphtheriae collected in mainland France and highlight several changes. The proportion of C. diphtheriae belfanti increased between 1977 and 2011 and it is the most frequent biotype recovered in recent years. Resistance to ciprofloxacin has increased and most isolates with decreased sensitivity belong to the belfanti biotype. Using multilocus sequence typing, we demonstrate that French isolates are distributed in a large number of sequence types and identify three distinct lineages. C. diphtheriae mitis and gravis form lineage I while C. diphtheriae belfanti forms lineages II and III. Almost all isolates of lineage II are part of a unique clonal complex or are very close to it. Most French isolates have a dtxR sequence homologous to that of toxigenic isolates, suggesting that if lyzogenised by a corynephage, they can express diphtheria toxin.
在法国本土，土生土长的产毒白喉棒状杆菌已经消失，但非产毒白喉棒状杆菌仍在传播。我们使用表型和分子工具，回顾性地描述了在法国本土收集的 103 株非产毒白喉棒状杆菌，并强调了几个变化。1977 年至 2011 年间，白喉棒状杆菌 belfanti 的比例增加，它是近年来最常见的生物型。对环丙沙星的耐药性增加，大多数敏感性降低的分离株属于 belfanti 生物型。通过多位点序列分型，我们证明法国分离株分布在大量的序列型中，并确定了三个不同的谱系。白喉棒状杆菌 mitis 和 gravis 形成谱系 I，而白喉棒状杆菌 belfanti 形成谱系 II 和 III。谱系 II 的几乎所有分离株都属于一个独特的克隆复合体或与之非常接近。大多数法国分离株的 dtxR 序列与产毒分离株的序列同源，这表明如果被携带白喉毒素的噬菌体溶原化，它们可以表达白喉毒素。
