不同鸭疫里默氏杆菌菌株携带生物被膜形成相关基因的分析

The distribution of the genes involved in biofilm formation in different Riemerella anatipestifer strains

为筛选鸭疫里默氏杆菌(RA)生物被膜形成过程中的关键基因,本研究先采用PCR检测了10个生物被膜形成相关基因在生物被膜形成强、弱和无的菌株中的分布,根据试验结果,比较了CH3株在置玻璃试管和12孔聚乙烯板中培养时5个生物被膜形成相关基因在转录水平上的差异。结果表明,21株RA中强、弱和无生物被膜形成的菌株分别占28.57%(6/21)、23.81%(5/21)和47.61%(10/21);这些RA菌株均携带asrpdp(Riean_0487)、dhdps(Riean_0023)、ftsQ(Riean_1039)和hthdp(Riean_0339)4个基因;而大部分生物被膜形成能力弱的菌株和不形成生物被膜的菌株不携带aminopeptidase N(Riean_0186)和hp1(JN986833)基因。Real-time PCR结果表明,CH3株在24孔板中培养至生物被膜形成初期(10 h)比同时在玻璃试管中静置培养时,细菌的aminopeptidase N、hthdp和dhdps基因mRNA转录水平分别升高62.1%、102.3%和62.5%。本研究为进一步解析RA生物被膜形成的分子机制等奠定基础。

To screen the crucial genes which are essential for biofilm formation by Riemerella anatipestifer, ten genes involved in the biofilm formation found in strong biofilm producer of R.anatipestifer CH3 strain, were detected by PCR in 21 R.anatipestifer isolates, which belonged to strong, weak and non-biofilm producers, respectively. Then, based on the detection results, the relative transcriptional levels of five genes from biofilm-forming bacteria of the CH3 isolate were compared with the planktonic CH3 isolate. The results showed that the strong, weak and non-biofilm producers accounted for 28.57% （6/21）, 23.81（5/21） and 47.61% （10/21） among the 21 R.anatipestifer isolates. On the other hand, all the tested R.anatipestifer carried asrpdp （Riean_0487）, dhdps （Riean_0023）, ftsQ （Riean_1039） and hthdp （Riean_0339）, while most of the weak and non-biofilm producers did not carry aminopeptidase N （Riean_0186） and hp1 （JN986833）. In addition, at the initial stage of biofilm formation （culture for 10 hours）, the relative transcriptional levels of aminopeptidase N, hthdp and dhdps in biofilm-forming CH3 were upregulated 62.1%, 102.3% and 62.5%, respectively, than those in planktonic CH3. The results provided a sound basis for fiurther studying the molecularmechanism of biofilm formation by R.anatipestifer.