中文摘要：

为探讨分子伴侣Hfq对溶藻弧菌（Vibrio alginolyticus）毒力的调控作用，本文分析了溶藻弧菌ZJ-T野生株、hfq突变株及回补株各项与毒力相关的生理生化指标。研究结果显示：在半固体和固体LBS平板中，缺失株游动和涌动能力显著降低（P〈0．001）；hfq缺失株生物膜合成速度及合成量降低，但解离速度增加；在限铁环境下，缺失株生长有所减弱；缺失株胞外蛋白酶分泌增强（P〈0．01）；同野生株和突变株相比，缺失株对小鼠成肌细胞系C2C12细胞几乎不致死，且其对石斑鱼的半数致死量提高3个数量级。实验结果表明：Hfq对溶藻弧菌毒力具有重要调控作用，并通过调控其运动、生物膜形成、铁代谢、胞外蛋白酶分泌等生理生化过程从而调控其毒力。本研究可为溶藻弧菌病害暴发的防治提供重要理论依据。

英文摘要：

To understand the role of Hfq in the virulence of Vibrio alginolyticus, we studied a series of virulence-related physiological and biochemical pathways comparatively among V. alginolyticus wild type strain Z J-T, hfq mutant strain Ahfq-T, and the complementary strain hfq＋-T. The results show that the swimming and swarming abilities of hfq null strain were significantly reduced （P〈0.001）. Deletion of hfq decreased the biofilm formation while promoted the deattachment of E alginolyticus. Hfq positively regulated iron metabolism and negatively regulated the secretion of extracellular proteases （ECPs） （P〈0.01）. Compared to the wild type and complementary strains, the hfq deficient strain completely lost the ability for inducing C2C12 cell death, and increased lethal dose （LDs0） to Epinephelus awoara by three orders of magnitude. Therefore, Hfq is crucial in the virulence of V. alginolyticus by regulating motility, bofilm formation, iron metabolism, and secretion of ECPs. This study may provide an insightful theoretical basis for the prevention of vibriosis.