Abstract
LactococcusCeduovirus (formerly c2virus) bacteriophages are among the three most prevalent phage types reported in dairy environments. Phages from this group conduct a strictly lytic lifestyle and cause substantial losses during milk fermentation processes, by infecting lactococcal host starter strains. Despite their deleterious activity, there are limited research data concerning Ceduovirus phages. To advance our knowledge on this specific phage group, we sequenced and performed a comparative analysis of 10 new Lactococcus lactis Ceduovirus phages isolated from distinct dairy environments. Host range studies allowed us to distinguish the differential patterns of infection of L. lactis cells for each phage, and revealed a broad host spectrum for most of them. We showed that 40% of the studied Ceduovirus phages can infect both cremoris and lactis strains. A preference to lyse strains with the C-type cell wall polysaccharide genotype was observed. Phage whole-genome sequencing revealed an average nucleotide identity above 80%, with distinct regions of divergence mapped to several locations. The comparative approach for analyzing genomic data and the phage lytic spectrum suggested that the amino acid sequence of the orf8-encoded putative tape measure protein correlates with host range. Phylogenetic studies revealed separation of the sequenced phages into two subgroups. Finally, we identified three types of phage origin of replication regions, and showed they are able to support plasmid replication without additional phage proteins.
Highlights
Ceduovirus phages infecting Lactococcus lactis starter strains are one of the three most prominent phage species in the dairy environment worldwide [1,2]
This observation seems intriguing given the fact that Ceduovirus phages have been repeatedly described to have a much wider host range compared to Skunavirus phages, and it would be expected that they would encounter a permissive strain more frequently and spread in the environment more [10,33,56,57]
We anticipated to deepen our knowledge on host-phage interactions and genetic diversity in relation to already sequenced Ceduovirus phages
Summary
Ceduovirus phages infecting Lactococcus lactis starter strains are one of the three most prominent phage species in the dairy environment worldwide [1,2] Phages classified to this type belong to the Siphoviridae family of the Caudovirales order, and are characterized by prolate heads and long non-contractile tails [3]. Despite the acknowledged ubiquity of Ceduovirus phages in milk plants, there is a significant deficiency in the amount of experimental data concerning this group of phages. This stands in strong contrast to the well-characterized and abundantly sequenced Lactococcus Skunavirus (formerly 936-type or sk1virus) type [4,5,6]. Less than 40 complete genome sequences of Ceduovirus phages were available in databases [7,8,9,10,11,12,13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
