Universidade do Estado de Santa Catarina, Centro de Diagnóstico Microbiológico Animal, Centro de Ciências Agroveterinárias, Av. Luiz de Camões, 2090, Bairro Conta Dinheiro, 88520-000 Lages, SC, Brazil.
Instituto Federal de Santa Catarina, Av. Mauro Ramos, 950, Centro, 88020-300 Florianópolis, SC, Brazil.
An Acad Bras Cienc. 2021 Apr 30;93(3):e20190200. doi: 10.1590/0001-3765202120190200. eCollection 2021.
Listeria monocytogenes is an opportunistic pathogen that causes listeriosis, a foodborne disease with low incidence but with high mortality rate in humans. This microorganism has been recovered from several dairy products, especially those produced with raw milk. The objective of this work was to investigate the presence of virulence genes, and also to define the antimicrobial susceptibility profile of L. monocytogenes isolates recovered from serrano artisanal cheese produced in Southern region of Brazil. Nine strains of L. monocytogenes (serotypes 1/2b and 4b) were evaluated through PCR to detect the presence of the virulence genes hly, inlA, inlC, inlJ, actA, plcB and iap, while antimicrobial susceptibility profile was determined via disk diffusion method. All strains exhibited the presence of the genes hly and plcB, whereas the other genes (iap, actA, inlA, inlC and inlJ) were only detected in eight strains. We verified that all strains were resistant to at least one antimicrobial agent and three of them showed multidrug resistance. These findings demonstrated the serrano artisanal cheese offers risks to consumers' health and point to a need of adaptations and monitoring of manufacturing process of this food, in order to prevent the dissemination of L. monocytogenes.
单增李斯特菌是一种机会致病菌，可引起李斯特菌病，这是一种食源性疾病，发病率低，但人类死亡率高。这种微生物已从几种乳制品中被回收，特别是那些用生奶生产的乳制品。本工作的目的是调查毒力基因的存在情况，并确定从巴西南部地区生产的塞拉诺手工奶酪中分离出的单核细胞增生李斯特菌的抗菌药物敏感性谱。通过 PCR 评估了 9 株单核细胞增生李斯特菌（血清型 1/2b 和 4b），以检测毒力基因 hly、inlA、inlC、inlJ、actA、plcB 和 iap 的存在情况，而抗菌药物敏感性谱则通过纸片扩散法确定。所有菌株均显示出 hly 和 plcB 基因的存在，而其他基因（iap、actA、inlA、inlC 和 inlJ）仅在 8 株菌株中检测到。我们发现所有菌株至少对一种抗菌药物具有耐药性，其中三种表现出多药耐药性。这些发现表明，塞拉诺手工奶酪对消费者的健康构成威胁，并指出需要对这种食品的生产工艺进行调整和监测，以防止单核细胞增生李斯特菌的传播。
