基于宏基因组分析鸡爪熟肉制品中微生物污染与基因信息

Metagenomic Analysis of Microbial Contamination and Genetic Information in Cooked Chicken Feet Products

采集10种鸡爪熟肉制品,用传统微生物培养法和宏基因组学方法分析鸡爪熟肉制品中微生物污染水平、群落组成及相关遗传信息。结果表明:7号样品菌落总数为1.3×10^(5) CFU/g,不符合GB 2726—2016《食品安全国家标准熟肉制品》限量要求,其他样品菌落总数结果均<10 CFU/g,微生物DNA浓度检测结果与菌落总数结果基本一致,可有效评估样品中微生物污染水平;1~6号和8~10号样品主要污染微生物为流产衣原体、大肠杆菌、肺炎克雷伯氏菌和鹦鹉衣原体,相对丰度分别为60.87%~75.49%、13.20%~18.41%、8.29%~16.41%和1.67%~3.67%,7号样品主要污染微生物为短乳杆菌、流产衣原体,相对丰度分别约为63%和8%,所有样品共检测到7种病毒,主要污染病毒为禽白血病病毒;共鉴定出12种抗生素耐药基因、10种BactMet基因,对四环素和吖啶橙等多种抗生素与化合物存在抗性;共鉴定出30种毒力因子基因,编码外膜受体、磷脂酶C等毒力因子;鲍氏不动杆菌携带7种抗生素耐药基因、5种BactMet基因及28种毒力因子基因,是超级耐药与致病菌。

A traditional culture method and metagenomic analysis were used to determine the level of microbial contamination,community composition and related genetic information in 10 samples of cooked chicken feet products.The results showed that the total bacterial count of sample 7 was 1.3×10^(5)CFU/g,which did not meet the requirements of the GB 2726-2016 National Food Safety Standard for Cooked Meat Products.The total bacterial counts of the other samples were all less than 10 CFU/g.The results of microbial DNA concentration and total bacterial count were basically consistent,thus being valid to assess the level of microbial contamination in the samples.The main contaminant bacteria in samples 1–6 and 8–10 were Chlamydia abortus,Escherichia coli,Klebsiella pneumoniae,and Chlamydia psittaci,with relative abundances of 60.87%–75.49%,13.20%–18.41%,8.29%–16.41%,and 1.67%–3.67%,respectively.The main contaminant bacteria in sample 7 were Lactobacillus brevis and C.abortus,with relative abundances of about 63%and 8%,respectively.A total of 7 viruses were detected in all samples,the main one being Avian leukemia virus.A total of 12 antibiotic resistance genes and 10 BactMet genes were identified,indicating resistance to various antibiotics and compounds such as tetracycline and acridine orange.A total of 30 virulence factor genes were identified,encoding outer membrane receptor,phospholipase C,and other virulence factors.Acinetobacter baumannii was found to carry 7 antibiotic resistance genes,5 BactMet genes,and 28 virulence factor genes,being a super antibiotic-resistant and pathogenic bacterium.