Abstracto

Genomic Diversity of Arcobacter spp. Isolated from Surface Waters

Rodrigo Alonso, Irati Martínez-Malaxetxebarria, Cecilia Girbau, Sandra Carmona, Héctor Velasco, Aurora Fernández-Astorga

A total of 45 non-clonal Arcobacter isolates recovered from wastewater and river water samples collected around Vitoria-Gasteiz, North of Spain, were investigated. Our findings confirmed A. butzleri as the most predominant species, although A. cryaerophilus and A. lanthieri were identified also. Eight isolates showed discordant results with the identification m-PCRs. Based on the rpoB gene sequence, two of these eight isolates turned to be A. lanthieri. However, the six remaining seemed to be possible new species needing additional analysis. The occurrence of virulence-associated genes was significantly (P<0.05) higher in A. butzleri. Seven of the ten virulence-associated genes investigated (ciaB, mviN, tlyA, cadF, pldA, cj1349 and hecA) were present in a high number of isolates. Among them, hecA gene was significantly (P<0.05) related to isolates from wastewater. MLST showed a high rate of genetic diversity for A. butzleri isolates. However, there were no signs of relationships between STs and the presence of virulence related genes. In conclusion, Arcobacter population in surface waters may be more varied in species than detected because most of the enrichment media and molecular techniques are designed based on A. butzleri and this may be biasing the information in favour of this species. Additionally, we found a possible relationship between the content of virulence-associated genes and the origin of the isolates.