University of California, Department of Fish, Wildlife, and Conservation Biology, Davis, California, USA.
USDA, ARS, Foodborne Toxin Detection and Prevention Research Unit, Albany, California, USA.
Appl Environ Microbiol. 2020 Dec 17;87(1). doi: 10.1128/AEM.01926-20.
is a foodborne pathogen that causes high rates of hospitalization and mortality in people infected. Contamination of fresh, ready to eat produce by this pathogen is especially troubling because of the ability of this bacterium to grow on produce under refrigeration temperatures. In this study, we created a library of over 8,000 plant phyllosphere-associated bacteria and screened them for the ability to inhibit the growth of in an fluorescence-based assay. One isolate, later identified as ALB65, was able to inhibit the fluorescence of by >30-fold ALB65 was also able to grow, persist, and reduce the growth of by >1.5 log CFU on cantaloupe melon rinds inoculated with 5 × 10 CFU at 30°C and was able to completely inhibit its growth at temperatures below 8°C. DNA sequence analysis of the ALB65 genome revealed six gene clusters that are predicted to encode genes for antibiotic production; however, no plant or human virulence factors were identified. These data suggest that ALB65 is an effective and safe biological control agent for the reduction of growth on intact cantaloupe melons and possibly other types of produce. is estimated by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration to cause disease in approximately 1,600 to 2,500 people in the United States every year. The largest known outbreak of listeriosis in the United States was associated with intact cantaloupe melons in 2011, resulting in 147 hospitalizations and 33 deaths. In this study, we demonstrated that ALB65 is an effective biological control agent for the reduction of growth on intact cantaloupe melons under both pre- and postharvest conditions. Furthermore, we demonstrated that ALB65 can completely inhibit the growth of during cold storage (<8°C).
是一种食源性病原体，可导致感染人群的住院率和死亡率居高不下。这种病原体污染新鲜的、即食的农产品尤其令人担忧，因为这种细菌在冷藏温度下能够在农产品上生长。在这项研究中，我们创建了一个超过 8000 种植物叶际相关细菌的文库，并通过荧光基础测定筛选了它们抑制生长的能力。一种分离株，后来被鉴定为 ALB65，能够抑制的荧光超过 30 倍。ALB65 也能够在接种了 5×10 CFU 的哈密瓜果皮上生长、持续存在，并使减少 1.5 个对数 CFU，在 30°C 下接种，并且能够在低于 8°C 的温度下完全抑制其生长。ALB65 基因组的 DNA 序列分析显示了六个基因簇，预计这些基因簇编码抗生素产生基因；然而，没有发现植物或人类的毒力因子。这些数据表明，ALB65 是一种有效且安全的生物防治剂，可减少完整哈密瓜上的生长，可能还有其他类型的农产品。据疾病控制和预防中心和美国食品和药物管理局估计，每年在美国约有 1600 至 2500 人患病。美国最大的李斯特菌病暴发与 2011 年完整的哈密瓜有关，导致 147 人住院和 33 人死亡。在这项研究中，我们证明了 ALB65 是一种有效的生物防治剂，可以减少完整哈密瓜上的生长，无论是在收获前还是收获后。此外，我们证明了 ALB65 可以在冷藏（<8°C）期间完全抑制的生长。
