Ruiz-Cruz Sofia, Parlindungan Elvina, Erazo Garzon Andrea, Alqarni Mona, Lugli Gabriele A, Ventura Marco, van Sinderen Douwe, Mahony Jennifer
School of Microbiology & APC Microbiome Ireland, University College Cork, Western Road, Cork T12 YT20, Ireland.
Laboratory of Probiogenomics, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43121 Parma, Italy.
Microorganisms. 2020 Oct 29;8(11):1685. doi: 10.3390/microorganisms8111685.
is the most widely exploited microorganism in global dairy fermentations. Lactococcal strains are described as typically harboring a number of prophages in their chromosomes. The presence of such prophages may provide both advantages and disadvantages to the carrying host. Here, we describe the deliberate generation of three distinct lysogens of the model lactococcal strain 3107 and the impact of additional prophage carriage on phage-resistance and anti-microbial susceptibility. Lysogen-specific responses were observed, highlighting the unique relationship and impact of each lysogenic phage on its host. Both homologous and heterologous phage-resistance profiles were observed, highlighting the presence of possible prophage-encoded phage-resistance factors. Superinfection exclusion was among the most notable causes of heterologous phage-resistance profiles with resistance observed against members of the , P335, P087, and 949 lactococcal phage groups. Through these analyses, it is now possible to identify phages that may pursue similar DNA injection pathways. The generated lysogenic strains exhibited increased sensitivity to the antimicrobial compounds, nisin and lysozyme, relative to the parent strain, although it is noteworthy that the degree of sensitivity was specific to the individual (pro)phages. Overall, the findings highlight the unique impact of each prophage on a given strain and the requirement for strain-level analysis when considering the implications of lysogeny.
是全球乳制品发酵中应用最广泛的微生物。乳球菌菌株通常被描述为在其染色体中携带多种原噬菌体。这些原噬菌体的存在可能对宿主带来利弊。在此，我们描述了模式乳球菌菌株3107三种不同溶原菌的特意产生，以及额外携带原噬菌体对噬菌体抗性和抗菌敏感性的影响。观察到了溶原菌特异性反应，突出了每种溶原性噬菌体与其宿主之间独特的关系和影响。观察到了同源和异源噬菌体抗性谱，突出了可能由原噬菌体编码的噬菌体抗性因子的存在。超感染排除是异源噬菌体抗性谱最显著的原因之一，观察到对P335、P087和949乳球菌噬菌体组成员具有抗性。通过这些分析，现在有可能识别可能采用相似DNA注入途径的噬菌体。相对于亲本菌株，所产生的溶原菌菌株对抗菌化合物乳链菌肽和溶菌酶表现出更高的敏感性，不过值得注意的是，敏感程度因个体（原）噬菌体而异。总体而言，研究结果突出了每种原噬菌体对给定菌株的独特影响，以及在考虑溶原性影响时进行菌株水平分析的必要性。
