IHU Méditerranée Infection, Marseille, France.
IRD, MEPHI, IHU Méditerranée Infection, Aix Marseille Univ., 19-21 Bd Jean Moulin, 13385, Marseillle Cedex 05, France.
Sci Rep. 2021 Feb 12;11(1):3777. doi: 10.1038/s41598-021-83236-7.
Mycobacterium ulcerans secrete a series of non-ribosomal-encoded toxins known as mycolactones that are responsible for causing a disabling ulceration of the skin and subcutaneous tissues named Buruli ulcer. The disease is the sole non-contagion among the three most common mycobacterial diseases in humans. Direct contact with contaminated wetlands is a risk factor for Buruli ulcer, responsible for M. ulcerans skin carriage before transcutaneous inoculation with this opportunistic pathogen. In this study, we analysed the bacterial and fungal skin microbiota in individuals exposed to M. ulcerans in Burkina Faso. We showed that M. ulcerans-specific DNA sequences were detected on the unbreached skin of 6/52 (11.5%) asymptomatic farmers living in Sindou versus 0/52 (0%) of those living in the non-endemic region of Tenkodogo. Then, we cultured the skin microbiota of asymptomatic M. ulcerans carriers and negative control individuals, all living in the region of Sindou. A total of 84 different bacterial and fungal species were isolated, 21 from M. ulcerans-negative skin samples, 31 from M. ulcerans-positive samples and 32 from both. More specifically, Actinobacteria, Aspergillus niger and Aspergillus flavus were significantly associated with M. ulcerans skin carriage. We further observed that in vitro, mycolactones induced spore germination of A. flavus, attracting the fungal network. These unprecedented observations suggest that interactions with fungi may modulate the outcome of M. ulcerans skin carriage, opening new venues to the understanding of Buruli ulcer pathology, prophylaxis and treatment of this still neglected tropical infection.
溃疡分枝杆菌分泌一系列非核糖体编码毒素，称为(mycolactones) ，这些毒素导致皮肤和皮下组织出现一种称为布鲁里溃疡的使人丧失能力的溃疡。这种疾病是人类三种最常见的分枝杆菌病中唯一一种非传染性疾病。直接接触受污染的湿地是布鲁里溃疡的一个危险因素，在这种机会性病原体经皮接种之前，导致溃疡分枝杆菌在皮肤中携带。在这项研究中，我们分析了在布基纳法索接触溃疡分枝杆菌的个体的细菌和真菌皮肤微生物群。我们表明，在辛杜的 52 名无症状农民中，有 6/52(11.5%)的未破裂皮肤上检测到了特定于溃疡分枝杆菌的 DNA 序列，而在非流行区滕科多戈的 52 名农民中，0/52(0%)的农民有这种情况。然后，我们培养了来自辛杜地区的无症状溃疡分枝杆菌携带者和阴性对照个体的皮肤微生物群。总共分离出 84 种不同的细菌和真菌物种，21 种来自无溃疡分枝杆菌的皮肤样本，31 种来自有溃疡分枝杆菌的样本，32 种来自两者都有的样本。更具体地说，放线菌、黑曲霉和黄曲霉与溃疡分枝杆菌的皮肤携带明显相关。我们进一步观察到，在体外，mycolactones 诱导黄曲霉孢子萌发，吸引真菌网络。这些前所未有的观察结果表明，与真菌的相互作用可能会调节溃疡分枝杆菌皮肤携带的结果，为理解布鲁里溃疡的病理学、预防和治疗这种仍被忽视的热带感染开辟了新的途径。
