GENOME ANALYSIS OF FIVE VIRULENT Leuconostoc PHAGES ISOLATED FROM BLUE CHEESE MANUFACTURE IN ARGENTINA

PUJATO, S. A.; MERCANTI, D.J.; GUGLIELMOTTI, D. M.; MOINEAU, S.; MOJICA, F. ; QUIBERON, A.

San Miguel de Tucumán

Simposio; V International Symposium on Lactic Acid Bacteria; 2016

CERELA - CONICET

Phages infecting Leuconostoc strains can be overlooked during milk fermentation because they do not slowdown the acidification process. However, they can negatively impact on the texture and the flavor profile of the final product. Yet, information about these phages is still scarce. In this work, the complete genome sequences of five Leuconostoc phages, virulent of Leuconostoc mesenteroides or Leuconostoc pseudomesenteroides strains, was determined. Leuconostoc phages were isolated from blue cheese manufactures in Argentina. The sequencing libraries were prepared with the Nextera XT DNA Sample Prep Kit (Illumina) according to the manufacturer?s instructions. The library was sequenced using a MiSeq Reagent Kit v2 on a MiSeq system (Illumina ? 500 cycles). The obtained sequences were analyzed using GeneMark (http://exon.gatech.edu/GeneMark/) and ORF Finder (http://www.ncbi.nlm.nih.gov/gor f.html) tools. Complete nucleotide analysis of these phages showed dsDNA genomes with sizes ranging from 25.7 to 28.9 kb, and the presence of 45 to 48 open reading frames (ORFs). The genomic G+C content was between 36,0 and 36,8%. Analysis of the genome extremities indicated that the analyzed phages are cos-type. The genes were organized in functional modules responsible for replication, packaging, head and tail morphogenesis, cell lysis and regulation and modification. Comparative genomics analysis allowed classifying the 5 phages into two groups, which correlates with the host species. High percentage of similarity within the group on both nucleotide and protein level was observed. The genomes of Argentinian Leuconostoc phages were highly similar to those previously characterized: ɸ1-A4 (USA, sauerkraut fermentation), ɸLN25 and ɸLNO4 (England, whey). This low diversity in Ln. mesenteroides phages could be an intrinsic feature, and/or the consequence of a limited number of Ln. mesenteroides strains used all over the world.