COMPARATIVE GENOMIC ANALYSIS AND PHYLOGENETIC STUDIES OF THE UBIQUITOUS Lactobacillus curvatus GROUP

TERAN, L. C.; ZAGOREC, M.; FADDA, S.; CHAILLOU, S.; RAYA, R.; CHAMPOMIER-VERGÈS, M.C.

San Miguel de Tucumán

Simposio; V International Symposium of Lactic Acid Bacteria; 2016

CERELA-CONICET

COMPARATIVE GENOMIC ANALYSIS AND PHYLOGENETIC STUDIES OF THE UBIQUITOUS Lactobacillus curvatus GROUPL.C. Terán1, R. Raya1, S. Fadda1, M. Zagorec2, M.C. Champomier-Vergès3, S. Chaillou31CERELA-CONICET. Chacabuco 145. 4000 San Miguel de Tucumán, Argentina. E-mail: lteran@cerela.org.ar2ONIRIS. INRA. UMR 1014 SECALIM, Groupe 5. Site de la Chantrerie, Route de gachet CS40706. 44307 Nantes cedex 3, France.3MICALIS. INRA AgroParisTech UMR1319. Domaine de Vilvert. Bat526. F78352 Jouy-en-Josas, France.Lactobacillus curvatus is mainly associated with fermented meat products and vacuum-packaged refrigerated meat. It was also isolated from fish, cheese, and sushi. This species belongs to the L. sakei clade of psychrotrophic Lactobacillus and is phylogenetically closely related to Lactobacillus sakei, Lactobacillus fuchuensis and Lactobacillus graminis. L. curvatus strains have biotechnologic potentials, such as bacteriocin production, to be applied as a starter and a bioprotective culture for meat products. In this work, we performed in silico comparative genome analysis of the L. curvatus group, including five strains isolated from different sources: the newly sequenced FLEC03, isolated from vacuum packaged beaf carpaccio; CRL705, from an Argentinian artisanal dry sausage; NRIC0822, from Japanese sushi; DSM20009, the type strain, isolated from milk and F16#9, from the human gut. The comparison was also extended to the closely related L. sakei 23k and L. graminis DSM20719. To assess the pangenomic diversity of this group, in terms of variability, we sought for strain-specific genes and, in terms of the core-genome, we studied the phylogenetic relation within this group. The sequences were ordered accordingly to the complete genome of L. sakei 23k. Manual annotation of all the strains was carried out using the Microscope Platform. Phylogenetic analyses were performed using progressive Mauve and Clonal Frame. Phylogenomic studies showed that L. curvatus clade is divided into two lineages, one of them is represented by strains DSM20019, F16#9, CRL705 and NRIC082, while the other is represented by FLEC03 strain, which is closer to the strain DSM20719 of L. graminis and to the strain 23k of L. sakei. This was confirmed with further analysis using multilocus sequence typing (MLST) using the dnaK, ldhL, tufA and hemN genes and extending the study to others 29 strains of L. curvatus. Taking together all the L. curvatus strains studied, the core genome is constituted by 1345 families of genes, which represents the 41.7% of the chromosome. Unlike L. sakei 23k, all L. curvatus -especially CRL705- and L. graminis DSM20719 present a wide repertoire of PTS systems for the uptake of sugars. We conclude that the L. curvatus group has a wide genomic variability, including significant strain-specific genes. L. curvatus is a ubiquitous species that has the ability to adapt and overcome different environmental conditions.