LFMFP, Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Member of Food2Know, Coupure Links 653, B-9000 Gent, Belgium.
LFMFP, Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Member of Food2Know, Coupure Links 653, B-9000 Gent, Belgium.
Int J Food Microbiol. 2015 Apr 16;199:41-6. doi: 10.1016/j.ijfoodmicro.2015.01.008. Epub 2015 Jan 15.
The psychrotrophic lactic acid bacterium (LAB) Leuconostoc gelidum subsp. gasicomitatum has emerged as one of the most prevalent specific spoilage organisms (SSOs) of packaged, cold-stored food products in Northern Europe. The whole genome sequencing of the type strain L. gelidum subsp. gasicomitatum LMG 18811(T) revealed genes encoding for proteins related to adhesion. In the present study the attachment of six food and environmental isolates was monitored on stainless steel (SS) and glass surfaces incubated (7 °C for 5-9 days) in two food simulating substrates (i.e. sweet bell pepper juice and boiled eggs in brine). The selection encompassed unique genotypes, isolated from different food products or sampling sites as well as slime-forming biotypes. The evaluation of the attached cells was performed with the bead vortexing method and a viability staining assay coupled with epifluorescence microscopy. On SS surfaces the slime-formers showed the lowest attachment (3.3-4.5 logCFU/cm(2)), while strain L. gelidum subsp. gasicomitatum ab2, which was isolated from an acetic acid bath in a vegetable salad company, reached significantly higher populations of attached cells exceeding 7 logCFU/cm(2). Strain ab2 formed dense cell aggregations on SS after 9 days of incubation in sweet bell pepper juice. The attachment ability of L. gelidum subsp. gasicomitatum on surfaces documented in the present study extends our knowledge and understanding of the spoilage potential and intra-subspecies diversity of this microbe.
嗜冷性乳酸菌（LAB）凝胶明串珠菌亚种 gasicomitatum 已成为北欧包装冷藏食品中最普遍的特定腐败菌（SSO）之一。该型菌株 L. gelidum subsp. gasicomitatum LMG 18811(T) 的全基因组测序揭示了与粘附相关的蛋白质编码基因。在本研究中，监测了 6 种食品和环境分离株在不锈钢（SS）和玻璃表面上的附着，这些表面在两种食品模拟基质（即甜椒汁和盐水煮鸡蛋）中孵育（7°C 5-9 天）。选择涵盖了独特的基因型，这些基因型分离自不同的食品或采样点以及粘液形成生物型。用珠子涡旋法和与荧光显微镜偶联的活菌染色测定法评估附着细胞。在 SS 表面上，粘液形成体的附着率最低（3.3-4.5 logCFU/cm(2)），而从蔬菜沙拉公司的醋酸浴中分离出的凝胶明串珠菌亚种 ab2 附着的细胞数量显著更高，超过 7 logCFU/cm(2)。ab2 菌株在甜椒汁中孵育 9 天后在 SS 上形成密集的细胞聚集。本研究中记录的凝胶明串珠菌亚种 gasicomitatum 在表面上的附着能力扩展了我们对该微生物腐败潜力和亚种内多样性的认识。
