Rathlavath S, Kumar S, Nayak B B
Quality Control Laboratory, Post-Harvest Technology Department, ICAR-Central Institute of Fisheries Education (CIFE), Mumbai, India.
Lett Appl Microbiol. 2017 Jul;65(1):42-49. doi: 10.1111/lam.12743. Epub 2017 May 31.
Arcobacter species are emerging food-borne and water-borne human pathogens associated mostly with food animals and their environment. The present study was aimed to isolate Arcobacter species from fish, shellfish and coastal water samples using two methods and to determine their genetic diversity. Of 201 samples of fish, shellfish and water samples analysed, 66 (32·8%) samples showed the presence of Arcobacter DNA from both Arcobacter enrichment broth and Bolton broth. Arcobacters were isolated from 58 (87·8%) and 38 (57·5%) of Arcobacter DNA-positive samples using Arcobacter blood agar and Preston blood agar, respectively. Arcobacter sp. identified by biochemical tests were further analysed by a genus-specific PCR, followed by a multiplex-PCR and 16S rRNA-RFLP. From both the methods, four different Arcobacter species namely Arcobacter butzleri, Arcobacter skirrowii, Arcobacter mytili and Arcobacter defluvii were isolated, of which A. butzleri was the predominant species. Enterobacterial repetitive intergenic consensus (ERIC)-PCR fingerprint analysis revealed that the arcobacters isolated in this study were genetically very diverse and no specific genotype was found associated with a specific source (seafood or water). Since pathogenic arcobacters are not known to be natural inhabitants of coastal marine environment, identifying the sources of contamination will be crucial for effective management of this problem.
Arcobacter sp. are emerging food- and water-borne human pathogens. In this study, comparison of two selective media suggested Arcobacter blood agar to be more efficient in yielding Arcobacter sp. from seafood. Furthermore, the isolation of Arcobacter sp. such as Arcobacter butzleri, A. skirrowii, A. mytili and A. defluvii from seafood suggests diverse sources of contamination of seafood by Arcobacter sp. Analysis of enterobacterial repetitive intergenic consensus sequence-PCR patterns of A. butzleri showed high genetic diversity and lack of clonality among the isolates. Arcobacter contamination of seafood is an emerging issue both from seafood safety and seafood trade point of view.
弓形杆菌属是新出现的食源性和水源性人类病原体，主要与食用动物及其环境相关。本研究旨在使用两种方法从鱼类、贝类和沿海水样中分离弓形杆菌属，并确定其遗传多样性。在分析的201份鱼类、贝类和水样中，66份（32.8%）样本在弓形杆菌增菌肉汤和博尔顿肉汤中均显示存在弓形杆菌DNA。分别使用弓形杆菌血琼脂和普雷斯顿血琼脂从58份（87.8%）和38份（57.5%）弓形杆菌DNA阳性样本中分离出弓形杆菌。通过生化试验鉴定的弓形杆菌属菌株进一步通过属特异性PCR进行分析，随后进行多重PCR和16S rRNA-RFLP分析。从这两种方法中均分离出四种不同的弓形杆菌属菌株，即布氏弓形杆菌、斯氏弓形杆菌、贻贝弓形杆菌和下水道弓形杆菌，其中布氏弓形杆菌是优势种。肠杆菌重复基因间共有序列（ERIC）-PCR指纹分析表明，本研究中分离的弓形杆菌在遗传上非常多样，未发现与特定来源（海鲜或水）相关的特定基因型。由于已知致病性弓形杆菌不是沿海海洋环境的天然居民，确定污染源对于有效管理这一问题至关重要。
弓形杆菌属是新出现的食源性和水源性人类病原体。在本研究中，两种选择性培养基的比较表明，弓形杆菌血琼脂从海鲜中分离出弓形杆菌属的效率更高。此外，从海鲜中分离出布氏弓形杆菌、斯氏弓形杆菌、贻贝弓形杆菌和下水道弓形杆菌等弓形杆菌属菌株，表明海鲜受弓形杆菌属污染的来源多样。对布氏弓形杆菌的肠杆菌重复基因间共有序列-PCR模式分析显示，分离株具有高度的遗传多样性且缺乏克隆性。从海鲜安全和海鲜贸易的角度来看，海鲜受弓形杆菌污染是一个新出现的问题。
