Genetic and functional characterisation of the lactococcal P335 phage-host interactions

Jennifer Mahony (1) , Joana Oliveira (1) , Barry Collins (1) , Laurens Hanemaaijer , Gabriele Andrea Lugli (2) , Horst H. Neve (3) , Marco Ventura (2) , Thijs Kouwen , Christian Cambillau (4) , Douwe van Sinderen (5)

1 School of Microbiology
2 UNIPR - Università degli studi di Parma = University of Parma
3 Dept Microbiol & Biotechnol
4 AFMB - Architecture et fonction des macromolécules biologiques
5 Department of Microbiology

Background: Despite continuous research efforts, bacterio(phages) infecting Lactococcus lactis starter strains persist as a major threat to dairy fermentations. The lactococcal P335 phages, which are currently classified into four sub-groups (I-IV), are the second most frequently isolated phage group in an industrial dairy context. Results: The current work describes the isolation and comparative genomic analysis of 17 novel P335 group phages. Detailed analysis of the genomic region of P335 phages encoding the so-called “baseplate”, which includes the receptor binding protein (RBP) was combined with a functional characterization of the RBP of sub-group III and IV phages. Additionally, calcium-dependence assays revealed a specific requirement for calcium by sub-group IV phages while host range analysis highlighted a higher number of strains with CWPS type A (11 of 39 strains) are infected by the P335 phages assessed in this study than those with a C (five strains), B (three of 39 strains) or unknown (one of 39 strains) CWPS type. Conclusions: These analyses revealed significant divergence among RBP sequences, apparently reflecting their unique interactions with the host and particularly for strains with a type A CWPS. The implications of the genomic architecture of lactococcal P335 phages on serving as a general model for Siphoviridae phages are discussed.

Mots clés: Bacteriophage; Dairy; Fermentation; Lactococcus lactis; Receptor-binding protein

Domaines: Bactériologie; Virologie; Génomique, Transcriptomique et Protéomique [q-bio.GN]

Jennifer Mahony, Joana Oliveira, Barry Collins, Laurens Hanemaaijer, Gabriele Andrea Lugli, et al.. Genetic and functional characterisation of the lactococcal P335 phage-host interactions. BMC Genomics, 2017, 18, pp.146. ⟨10.1186/s12864-017-3537-5⟩. ⟨hal-01802812⟩