Gutierrez Maximiliano G, Colombo María I
Instituto de Histología y Embriología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina.
Autophagy. 2005 Oct-Dec;1(3):179-81. doi: 10.4161/auto.1.3.2063. Epub 2005 Oct 29.
Coxiella burnetii is a Gram-negative obligate intracellular bacterium that infects a wide range of hosts including humans, causing Q fever, a disease characterized by high fever and flu-like symptoms. After its internalization the Coxiella-containing phagosomes interact with intracellular compartments and generate a large replicative vacuole that displays certain characteristics of a phagolysosome. We have shown that this bacterially-customized replicative vacuole also has the hallmarks of an autophagosomal compartment. Furthermore, in a recent publication we have reported that induction of autophagy is beneficial for the replication and survival of Coxiella. Different morphological forms of this bacterium have been described during its developmental cycle. Here we present additional data and discuss a model indicating that induction of autophagy favors the differentiation of the Coxiella small cell variants to the metabolically active large cells variants. We postulate that nutrient acquisition, likely by fusion with the nutrient-rich autophagic vacuoles, triggers the development of the large cell variants which actively multiply in the host cell.
伯氏考克斯氏体是一种革兰氏阴性专性细胞内细菌，可感染包括人类在内的多种宿主，引发Q热，该病的特征为高热和流感样症状。内化后，含考克斯氏体的吞噬体与细胞内区室相互作用，形成一个具有吞噬溶酶体某些特征的大型复制泡。我们已经证明，这个细菌定制的复制泡也具有自噬体区室的特征。此外，在最近发表的一篇文章中，我们报道自噬的诱导有利于考克斯氏体的复制和存活。在其发育周期中，已描述了该细菌的不同形态形式。在此，我们展示了更多数据，并讨论了一个模型，该模型表明自噬的诱导有利于考克斯氏体小细胞变体向代谢活跃的大细胞变体分化。我们推测，营养获取可能是通过与富含营养的自噬泡融合实现的，这触发了大细胞变体的发育，这些变体在宿主细胞中积极增殖。
