Lambrechts Karlene, Gouws Pieter, Rip Diane
Department of Food Science, Stellenbosch University, 7602, South Africa.
AIMS Microbiol. 2024 Aug 7;10(3):608-643. doi: 10.3934/microbiol.2024029. eCollection 2024.
is a concern in seafood and its food processing environment (FPE). Several outbreaks globally have been linked to various types of seafood. Genetic profiling of is valuable to track bacterial contamination throughout the FPE and in understanding persistence mechanisms, with limited studies from South Africa. Forty-six isolates from origins: Fish/seafood products (n = 32) (salmon, smoked trout, fresh hake, oysters), the FPE (n = 6), and clinical (n = 8) were included in this study. Lineage typing, antibiotic susceptibility testing, and screening for two genes ( and ) conferring sanitizer tolerance was conducted. The seafood and FPE isolates originated from seven different factories processing various seafood products with undetermined origin. All clinical isolates were categorized as lineage I, and seafood and FPE isolates were mostly categorized into lineage II (p < 0.01). Seafood and FPE isolates (53%) carried the gene cassette and one fish isolate, the gene. A subset, n = 24, was grouped into serotypes, sequence types (STs), and clonal complexes (CCs) with whole genome sequencing (WGS). Eight CCs and ten STs were identified. All clinical isolates belonged to serogroup 4b, hypervirulent CC1. CC121 was the most prevalent in isolates from food and the FPE. All isolates carried pathogenicity islands (LIPI) 1 and 2. LIPI-3 and LIPI-4 were found in certain isolates. We identified genetic determinants linked to enhanced survival in the FPE, including stress survival islets (SSI) and genes conferring tolerance to sanitizers. SSI-1 was found in 44% isolates from seafood and the FPE. SSI-2 was found in all the ST121 seafood isolates. Isolates (42%) harbored transposon Tn1688_qac (), conferring tolerance to quaternary ammonium compounds. Five plasmids were identified in 13 isolates from seafood and the FPE. This is the first One Health study reporting on genetic diversity, virulence and resistance profiles from various types of seafood and its FPE in South Africa.
是海鲜及其食品加工环境（FPE）中的一个问题。全球多起疫情暴发都与各类海鲜有关。对 进行基因分型有助于追踪整个食品加工环境中的细菌污染情况，并了解其持续存在的机制，但南非在这方面的研究有限。本研究纳入了46株来自不同来源的 分离株：鱼类/海鲜产品（n = 32）（三文鱼、烟熏鳟鱼、新鲜无须鳕、牡蛎）、食品加工环境（n = 6）以及临床样本（n = 8）。进行了谱系分型、抗生素敏感性测试以及对两个赋予消毒剂耐受性的基因（ 和 ）的筛查。海鲜和食品加工环境分离株来自七家加工各类海鲜产品但来源不明的不同工厂。所有临床分离株均归类为谱系I，而海鲜和食品加工环境分离株大多归类为谱系II（p < 0.01）。海鲜和食品加工环境分离株（53%）携带 基因盒，一株鱼类分离株携带 基因。通过全基因组测序（WGS）将一个包含24株分离株的子集分为血清型、序列类型（STs）和克隆复合体（CCs）。共鉴定出8个克隆复合体和10个序列类型。所有临床分离株均属于4b血清群、高毒力CC1。CC121在食品和食品加工环境分离株中最为常见。所有分离株均携带1型和2型 致病岛（LIPI）。在某些分离株中发现了LIPI - 3和LIPI - 4。我们确定了与在食品加工环境中增强生存能力相关的遗传决定因素，包括应激生存岛（SSI）和赋予消毒剂耐受性的基因。在44%的海鲜和食品加工环境分离株中发现了SSI - 1。在所有ST121海鲜分离株中均发现了SSI - 2。42%的分离株携带转座子Tn1688_qac（ ），赋予对季铵化合物的耐受性。在13株来自海鲜和食品加工环境的分离株中鉴定出了5种质粒。这是南非第一项关于 来自各类海鲜及其食品加工环境的遗传多样性、毒力和耐药性概况的“同一健康”研究报告。
