Quorum sensing is a widespread form of cell-to-cell communication, which is based on the production of signaling molecules known as autoinducers (AIs). The first group contains highly species-specific N-acyl homoserine lactones (N-AHLs), generally known as AI-1, which are produced by AHL synthase. The second group, possessing the characteristic structure of a furanone ring, are known as AI-2. The enzyme responsible for their production is S-ribosylhomocysteine lyase (LuxS). In Campylobacter jejuni, AI-2 and LuxS play a role in many important processes, including biofilm formation, stress response, motility, expression of virulence factors, and colonization. However, neither the receptor protein nor the exact structure of the AI-2 molecule have been identified to date. Similarly, little is known about the possible existence of AHL-synthase producing AI-1 and its impact on gene expression. Recently, an analogue of homoserine lactone, called cjA, was isolated from a cell-free supernatant of C. jejuni strain 81-176 and from the food isolate c11. The molecule cjA particularly impacted the expression of virulence factors and biofilm formation. This review summarizes the role of AI-2 and cjA in the context of biofilm formation, motility, stress responses, and expression of virulence factors.

中文翻译：

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分子自诱导物2和cjA及其对空肠弯曲杆菌基因表达的影响。

群体感应是细胞间通信的一种普遍形式，其基础是产生称为自动诱导物（AI）的信号分子。第一组包含高度物种特异性的N-酰基高丝氨酸内酯（N-AHL），通常称为AI-1，由AHL合酶产生。具有呋喃酮环的特征结构的第二组称为AI-2。产生它们的酶是S-核糖基同型半胱氨酸裂合酶（LuxS）。在空肠弯曲杆菌中，AI-2和LuxS在许多重要过程中起作用，包括生物膜形成，应激反应，运动，毒力因子表达和定植。但是，至今尚未鉴定出受体蛋白或AI-2分子的确切结构。同样，关于产生AHL的AHL合酶的可能存在及其对基因表达的影响知之甚少。最近，从空肠弯曲杆菌菌株81-176的无细胞上清液和食品分离物c11中分离了高丝氨酸内酯类似物cjA。分子cjA特别影响毒力因子的表达和生物膜的形成。这篇综述总结了AI-2和cjA在生物膜形成，运动，应激反应和毒力因子表达方面的作用。