大菱鲆源蜂房哈夫尼亚菌群体感应现象及生物被膜调控的研究

本文以腐败大菱鲆中分离得到的一株具有群体感应现象的细菌为研究对象,通过生理生化试验及16S r RNA鉴定其为蜂房哈夫尼亚菌(Hafnia alvei,Ha-01)。利用检测菌株紫色杆菌CV026及根癌农杆菌A136进行平行划线检测其信号分子(N-酰基高丝氨酸内酯,AHLs),并利用平板打孔法研究其分泌AHLs动力学及不同生长阶段生物被膜产生量,同时通过添加外源信号分子研究AHLs与生物被膜形成的关系。结果显示,菌株Ha-01能够产生群体感应现象,在培养过程中信号分子产生量呈现先升高后降低的趋势,且在16时达到最大值;生物被膜产生量与培养时间呈正相关,在72时达到最大值,然后逐渐趋于稳定,且添加外源AHLs标准品能够促进生物被膜的形成。研究证实,菌株Ha-01能够产生群体感应现象且能够调控生物被膜的形成。

Study of Quorum Sensing and Biofilm Formation of Hafnia alvei Separated from Turbot

One quorum-sensing (QS) strain separated from a spoiled turbot sample was used as the study object and determined as Hafnia alvei (Ha-01) according to physiological and biochemical tests and 16S rRNA analysis. The QS compounds [N-acyl-homoserine lactones (AHLs)] were detected by parallel-streak method using Chromobacterium violaceum CV026 and Agrobacterium tumefaciens A136. Additionally, the plate-diffusion method was used to study the kinetics of AHL secretion and the amount of biofilm produced in different growth phases, and exogenous signaling molecules were added to study the relationship between AHLs and biofilm formation. The results indicated that strain Ha-01 produced QS phenomena, and the number of AHLs produced by Ha-01 during cultivation exhibited a downward trend after the initial increase, reaching the maximum at 16 h. The amount of biofilm formed was positively correlated with incubation time and reached a maximum at 72 h, followed by gradual stabilization. The addition of exogenous AHL strands could promote the production of biofilm. These results indicated that strain Ha-01 was capable of producing QS phenomena and regulating biofilm formation.