Determination of Lactococcus formosensis Predicted Virulence Factors


Selcuk 9th International Conference on Applied Sciences, Konya, Turkey, 15 - 17 December 2023

  • Publication Type: Conference Paper / Summary Text
  • City: Konya
  • Country: Turkey
  • Recep Tayyip Erdoğan University Affiliated: Yes


Lactococcus species are generally considered non-pathogenic and are mostly associated with their usage in the production of fermented foods. However, several Lactococcus species with known and emerging clinical consequences in fish have been identified including L. garvieae, L. plantarum, L. piscium, L. raffinolactis, L. formosensis, and L. petauri. L. formosensis, and L. petauri share a noteworthy percentage of their genome with L. garvieae and have also been recently identified as etiologic agents of lactococcosis in various fish species like trout and catfish. It is an opportunistically zoonotic, Gram-positive bacteria responsible for costly outbreaks of high mortality in wild and cultured fish populations. Clinical appearance of infections caused by L. garvieae, L. petauri, or L. formosensis is similar and can include acute hemorrhagic septicemia, erratic swimming, lethargy, exophthalmia, anorexia, skin pigmentation changes, and moderate to high mortality in affected systems. In this study, we evaluated L. formosensis genomes, which are publicly available on NCBI (National Center for Biotechnology Information) database. For the phylogenetic relationship of genomes, a phylogenetic tree was built with core genomes, and an ANI (Average Nucleotide Identity) value was calculated. To identify virulence factors, VFDB (Virulence Factor Database) software was used. The results showed that adherence, adhesion, anti-phagocytosis, biofilm formation, enzyme, immune evasion, invasion, iron uptake, nutritional virulence, protease, and surface protein anchoring related virulence factor genes were identified. Virulence factors can vary between bacterial strains within the same species, so further detailed studies might be required to understand the potential virulence factors of L. formosensis.