Gui Meng, Liu Lei, Wu Ruiyun, Hu Jingrong, Wang Shun, Li Pinglan
Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
Beijing Fisheries Research Institute, Beijing, China.
Front Microbiol. 2018 Jul 31;9:1712. doi: 10.3389/fmicb.2018.01712. eCollection 2018.
Sturgeon is an important fresh water-culture fish in China. A problem with sturgeon is its high susceptibility to spoilage. Food spoilage is reported to be regulated by quorum sensing (QS). To identify the QS signals acetylated homoserine lactones (AHLs) in sturgeon and test whether QS plays a role in the spoilage of sturgeon, we investigated the specific spoilage organisms (SSOs) in vacuum packaged sturgeon stored at 4°C and the production of AHLs by sturgeon SSOs. 16S rDNA sequencing and spoilage capabilities analysis revealed that LP-11, LPJ-2, and LPC-3 were the SSOs in sturgeon. Among the three SSOs, only LP-11 induced the QS biosensors KYC55 and CV026, suggesting that it produced AHLs. Analysis by thin layer chromatography, high-performance liquid chromatography-triple quadrupole tandem mass spectrometry, and high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC/qTOF-MS) identified that the AHLs produced by were C6-SHL, C8-HSL, 3-oxo-C8-HSL, and 3-OH-C8-HSL. Our study revealed that QS system was probably involved in the regulation of sturgeon spoilage and for the first time reported the production of C8-HSL and 3-OH-C8-HSL by genus . As only HPLC/qTOF-MS effectively and accurately identified all the four AHLs produced by LP-11, this study also showed that HPLC/qTOF-MS was the most efficient method for rapid analysis of AHLs in complex microbial sample. The study provides new insight into the microbiology of sturgeon spoilage which may be helpful for better sturgeon preservation.
鲟鱼是中国重要的淡水养殖鱼类。鲟鱼存在的一个问题是其极易变质。据报道，食品变质受群体感应（QS）调控。为了鉴定鲟鱼中的群体感应信号乙酰化高丝氨酸内酯（AHLs），并测试群体感应是否在鲟鱼变质过程中起作用，我们研究了在4°C下储存的真空包装鲟鱼中的特定腐败菌（SSOs）以及鲟鱼SSOs产生AHLs的情况。16S rDNA测序和腐败能力分析表明，LP-11、LPJ-2和LPC-3是鲟鱼中的SSOs。在这三种SSOs中，只有LP-11能诱导群体感应生物传感器KYC55和CV026，这表明它能产生AHLs。通过薄层色谱、高效液相色谱 - 三重四极杆串联质谱和高效液相色谱四极杆飞行时间质谱（HPLC/qTOF-MS）分析确定，LP-11产生的AHLs为C6-SHL、C8-HSL、3-氧代-C8-HSL和3-羟基-C8-HSL。我们的研究表明群体感应系统可能参与了鲟鱼腐败的调控，并且首次报道了某属产生C8-HSL和3-羟基-C8-HSL。由于只有HPLC/qTOF-MS能有效且准确地鉴定出LP-11产生的所有四种AHLs，本研究还表明HPLC/qTOF-MS是快速分析复杂微生物样品中AHLs的最有效方法。该研究为鲟鱼腐败微生物学提供了新的见解，这可能有助于更好地保存鲟鱼。
