de Oliveira Fábio Muniz, Corrêa Viviane Lopes Rocha, Corrêa André França, da Costa Adeliane Castro, Procopio Victor Oliveira, Junqueira-Kipnis Ana Paula, Kipnis André
Tropical Institute of Pathology and Public Health, Federal University of Goiás, Rua 235 esquina com 1a avenida S/N, Setor Universitário, Goiânia, Goiás CEP 7405-050 Brazil.
Indian J Microbiol. 2019 Jun;59(2):180-187. doi: 10.1007/s12088-019-00788-z. Epub 2019 Feb 27.
Iron (Fe) homeostasis control is important for both pathogen and the host. During infection, the host reduces the access of microorganisms to iron, however, studies have shown that virulent pathogens are capable to sequester Fe from host proteins, and establish the infection. subsp. (Mycma), that is resistant to most drugs used against tuberculosis, was responsible for outbreaks around the world showing increased virulence when compared to other rapidly growing mycobacteria. The goal of this study was to determine whether Mycma produce siderophores and if the gene expression, a putative homolog of gene located in the gene cluster, is related to the synthesis of these molecules. For that, the effect of different iron concentrations on the growth of Mycma, the expression of gene, and the production of siderophores was evaluated in vitro and in vivo. It is shown that Mycma produce siderophores under iron deprivation conditions and gene expression was influenced by iron availability. The gene expression was also increased after macrophage or in vivo infection indicating that mycobactin synthesis by Mycma could participate in the Fe sequestration from the host during infection. In conclusion, we show that Mycma produces siderophores under iron deprivation conditions and that the gene is involved in this process, furthermore, this gene expression is induced during infection.
铁（Fe）稳态控制对病原体和宿主都很重要。在感染期间，宿主会减少微生物获取铁的机会，然而，研究表明，致病性病原体能够从宿主蛋白中螯合铁，并引发感染。 亚种（Mycma），对大多数用于治疗结核病的药物具有抗性，与其他快速生长的分枝杆菌相比，它在世界各地引发的疫情显示出更强的毒力。本研究的目的是确定Mycma是否产生铁载体，以及位于基因簇中的假定 基因同源物 基因的表达是否与这些分子的合成有关。为此，在体外和体内评估了不同铁浓度对Mycma生长、 基因表达和铁载体产生的影响。结果表明，Mycma在缺铁条件下产生铁载体，并且 基因表达受铁可用性的影响。巨噬细胞感染或体内感染后， 基因表达也会增加，这表明Mycma合成的分枝杆菌素可能参与感染期间从宿主中螯合铁的过程。总之，我们表明Mycma在缺铁条件下产生铁载体，并且 基因参与了这一过程，此外，该基因在感染期间被诱导表达。
