一株假交替单胞菌DL3的抑菌与群体感应淬灭活性研究

本实验室从水产养殖池防污附钢片的微生物黏膜中分离到一株菌DL3,为了明确该菌株的活性及作为有益菌进行应用的可能，通过细菌分离培养、16S rRNA测序和系统发育分析对其做了初步鉴定，并采用牛津杯法、平板法分别测定了菌株的抑菌活性和群体感应淬灭活性。基于菌株DL3 16S rRNA基因序列的系统发育分析表明，该菌株与解肽假交替单胞菌(Pseudoalteromonas peptidolytica)NBRC 101021^T的相似性最高，亲缘关系最近，为99.64%;抑菌试验显示，该菌株对鳗弧菌(Vibrio anguillarum)和铜绿假单胞菌(Pseudomonas aeruginosa)的抑制作用最强，对金黄色葡萄球菌(Staphylococcus aureus)、大肠埃希菌(Escherichi coli)、沙门氏菌(Salmonella)、链球菌(Streptococcus)、志贺氏杆菌(Shigella)、河弧菌(V.fluvialis)、东方弧菌(V.orientalis)、哈维氏弧菌(V.harveyi)和短小芽孢杆菌(Bacillus pumilus...

Study on antibacterial and quorum quenching activity of a Pseudoalteromonas sp. DL3

In this study, a strain DL3 was isolated from the microbial mucous membrane of antifouling attached steel sheet in aquaculture ponds. In order to clarify the activity of this strain and its potential application as beneficial bacteria, it was preliminarily identified by bacterial isolation culture, 16S rRNA sequencing and phylogenetic analysis. Oxford cup method and plate method were used to determine the bacteriostatic activity and quorum quenching activity. Based on phylogenetic analysis of the 16S rRNA gene sequence of strain DL3, this strain had the highest similarity with Pseudoalteromonas peptidolytica NBRC 101021T, with the closest affinity of 99.64%. The bacteriostasis test showed that the strain could significantly inhibit the growth of V. anguillarum and Pseudomonas aeruginosa, and showed that could inhibit the growth of Staphylococcus aureus, Escherichi coli, Salmonella, Streptococcus, Shigella, V. fluvialis, V. orientalis, V. harveyi and Bacillus pumilus to different degrees, and the antibacterial activity was strongest when cultured till 72 h. From the results of plate test, the strain DL3 had quorum quenching activity and could quench signal molecules such as 3-OXO-C6-HSL, C10-HSL, C12-HSL and 3-OXO-C14-HSL. In this study, the strain DL3 was successfully isolated and its antagonistic activity against pathogenic bacteria was clarified, which laid a foundation for further studies on the antibacterial mechanism of strain DL3 and its active products and the application of marine microorganisms in the prevention and control of animal bacterial diseases.