AHLs对不同菌株产生物胺的影响及菌株生物被膜特性分析

Effect of N-acylhomoserine Lactones on Biogenic Amine Production from Bacteria and Analysis of Biofilm Formation Characteristics

本文选取新疆熏马肠中产生物胺优势菌克雷伯氏菌、阴沟肠杆菌、成团泛菌作为研究对象,根癌农杆菌A136平行线法检测信号分子,现象表明3株优势菌均能发生群体感应现象。AHLs活性检测、生物胺检测及β-半乳糖苷酶活力与生物胺相关性分析,结果表明:克雷伯氏菌、成团泛菌的β-半乳糖苷酶活力与腐胺、尸胺、组胺、酪胺均显著相关(RPerson均在0.817之上,P<0.01);阴沟肠杆菌β-半乳糖苷酶活力与尸胺显著相关(RPerson=0.923,P=0.00<0.01);因此,AHLs分泌影响生物胺累积,具有协同作用。通过28℃、37℃生物被膜试验、细胞疏水性试验,结果表明:3株优势菌对二甲苯、三氯甲烷、乙酸乙酯吸附能力不同,细胞疏水值均不同;克雷伯氏菌形成生物被膜的能力差异不显著(P=0.095>0.05),阴沟肠杆菌、成团泛菌形成被膜的能力差异显著(P=0.0315<0.05,P=0.047<0.05)。因此,细胞疏水性能、培养时间、温度影响优势菌生物被膜形成。

In this study, Klebsiella spp., Enterobacter cloacae, and Pantoea agglomerans, which are dominant biogenic amine-producing bacteria in smoked and fermented horsemeat sausages, were used as test strains; quorum-sensing compounds were detected by a parallel line assay of Agrobacterium tumefaciens A136, and experimental evidence showed that quorum sensing was observed in all three of the dominant strains. N-acylhomoserine lactone（AHL） activity assay, detection, and quantification of biogenic amines, as well as correlation analysis betweenβ-galactosidase activityandbiogenicamineswereconducted.TheresultsindicatedthatbothKlebsiellaspp.andtheβ-galactosidase activityinP.agglomerans showed a significant positive correlation（RPearson 〉 0.817, P 〈 0.01） with putrescine, cadaverine, histamine, and tyramine. Theβ-galactosidase activityinE.cloacaewassignificantlycorrelatedwithcadaverine（RPearsonis0.923,P=0.00〈0.01）.Inaddition,thesecretionof AHLs affected the accumulation of biogenic amines, showing a synergistic effect. Meanwhile, biofilm formation and cell hydrophobicity experiments were carried out at 28 ℃ and 37 ℃, respectively. The results indicated that the absorption capacities of xylene, chloroform, and ethyl acetate, as well as cell hydrophobicity values were different for the three dominant strains. Furthermore, the ability of Klebsiella spp. to form biofilms did not show significant difference（P = 0.095 〉 0.05）, while significant differences（P = 0.0315 〈 0.05, P = 0.047 〈 0.05） were observed for E. cloacae and P. agglomerans. Therefore, cell hydrophobicity, incubation time, and temperature affected the ability of the dominant bacteria to form biofilms.