Genetic investigation within Lactococcus garvieae revealed two genomic lineages

Ferrario, Chiara; Ricci, Giovanni; Borgo, Francesca; Rollando, Rollando; Fortina, María Grazia

doi:10.1111/j.1574-6968.2012.02591.x

Cited by 30 publications

(29 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This bacterial species is also found in different food matrices 10 . In addition, clinical cases associated with L. garvieae infection, albeit rare, have been reported in humans 11 .…”

Section: Introductionmentioning

confidence: 82%

Characterization of prophages of Lactococcus garvieae

Eraclio

Fortina

Labrie

et al. 2017

Sci Rep

View full text Add to dashboard Cite

This report describes the morphological characterization and genome analysis of an induced prophage (PLg-TB25) from a dairy strain of Lactococcus garvieae. The phage belongs to the Siphoviridae family and its morphology is typical of other lactococcal phages. A general analysis of its genome did not reveal similarities with other lactococcal phage genomes, confirming its novelty. However, similarities were found between genes of its morphogenesis cluster and genes of Gram-positive bacteria, suggesting that this phage genome resulted from recombination events that took place in a heterogeneous microbial environment. An in silico search for other prophages in 16 L. garvieae genomes available in public databases, uncovered eight seemingly complete prophages in strains isolated from dairy and fish niches. Genome analyses of these prophages revealed three novel L. garvieae phages. The remaining prophages had homology to phages of Lactococcus lactis (P335 group) suggesting a close relationship between these lactococcal species. The similarity in GC content of L. garvieae prophages to the genomes of L. lactis phages further supports the hypothesis that these phages likely originated from the same ancestor.

show abstract

“…This bacterial species is also found in different food matrices 10 . In addition, clinical cases associated with L. garvieae infection, albeit rare, have been reported in humans 11 .…”

Section: Introductionmentioning

confidence: 82%

Characterization of prophages of Lactococcus garvieae

Eraclio

Fortina

Labrie

et al. 2017

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The host range of phage GE1 was assessed using a collection of 73 L. garvieae strains and 58 industrial L. lactis strains. Phage GE1 was highly specific as it infected only two L. garvieae strains, its host INS1 and strain INS2, which was isolated from a similar ecological niche (vegetables) (21). Phage GE1 did not infect any of the 58 L. lactis strains tested.…”

Section: Resultsmentioning

confidence: 98%

“…garvieae strains are found in raw milk and in a range of aquatic and terrestrial environments (21). Some L. garvieae strains may also be major components of the autochthonous microbial populations of certain artisanal cheeses (5).…”

Section: Discussionmentioning

confidence: 99%

“…A total of 73 L. garvieae strains previously isolated from different ecological niches (fish and dairy farms, vegetables, meat, and cereals) (21) and 58 industrial L. lactis strains were used to determine the host range of the phage. Lactococcal strains were grown statically at 30°C in M17 broth (Oxoid) supplemented with 0.5% glucose (GM17) or lactose (LM17).…”

Section: Methodsmentioning

confidence: 99%

“…The host range of phage GE1 was assessed by spotting 5 l of a 10 Ϫ2 dilution of a phage lysate on top agar containing one lactococcal strain. One-step growth assays were performed in triplicate with a multiplicity of infection (MOI) of 0.05 and the host strain L. garvieae INS1 (21). The burst size was calculated by dividing the average phage titer after the exponential phase by average titer before the infected cells began to release virions (25).…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

A Virulent Phage Infecting Lactococcus garvieae, with Homology to Lactococcus lactis Phages

Eraclio

Tremblay

Lacelle-Côté

et al. 2015

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

A new virulent phage belonging to the Siphoviridae family and able to infect Lactococcus garvieae strains was isolated from compost soil. Phage GE1 has a prolate capsid (56 by 38 nm) and a long noncontractile tail (123 nm). It had a burst size of 139 and a latent period of 31 min. Its host range was limited to only two L. garvieae strains out of 73 tested. Phage GE1 has a doublestranded DNA genome of 24,847 bp containing 48 predicted open reading frames (ORFs). Putative functions could be assigned to only 14 ORFs, and significant matches in public databases were found for only 17 ORFs, indicating that GE1 is a novel phage and its genome contains several new viral genes and encodes several new viral proteins. Of these 17 ORFs, 16 were homologous to deduced proteins of virulent phages infecting the dairy bacterium Lactococcus lactis, including previously characterized prolate-headed phages. Comparative genome analysis confirmed the relatedness of L. garvieae phage GE1 to L. lactis phages c2 (22,172 bp) and Q54 (26,537 bp), although its genome organization was closer to that of phage c2. Phage GE1 did not infect any of the 58 L. lactis strains tested. This study suggests that phages infecting different lactococcal species may have a common ancestor. Lactococcus garvieae is the etiological agent of lactococcosis, a pathology affecting a variety of fish species that is responsible for significant economic losses in both marine and freshwater aquacultures (1). In addition, L. garvieae has been associated with subclinical intramammary infections in cows (2). More recently, L. garvieae was associated with infections in humans and is now considered an opportunistic and potentially zoonotic pathogen (3, 4). In an effort to find its ecological niches, genetic investigations have revealed its presence, and sometimes dominance, in several habitats: river and sewage waters and raw and processed foods, including milk, meats, and vegetables (5-7).Despite growing attention, genomic characterization of L. garvieae progresses slowly, yet the evolutionary history and global diversity of this emerging pathogen are particularly interesting. The population structure and diversity of L. garvieae strains have been studied using comparative genome analysis, which led to the development of a multilocus sequence type (MLST) scheme to identify specific strains (8). These studies also revealed that L. garvieae is related to Lactococcus lactis, a nonpathogenic bacterium used for the manufacture of several fermented dairy products (9). Divergent genomic lineages were observed, with some ecotypes representing evolutionary intermediates between L. lactis and L. garvieae (8). The presence of insertion sequences (ISs) was also highly variable among L. garvieae strains (10). Analysis of these ISs within individual genomes revealed limited intragenomic sequence diversity, suggesting that many ISs in L. garvieae are evolutionarily young and may have been only recently acquired. Of note, the similarity of most L. garvieae ISs to L. lactis ISs suggests...

show abstract

Detection of virulence-related genes in Lactococcus garvieae and their expression in response to different conditions

et al. 2017

Self Cite

View full text Add to dashboard Cite

Lactococcus garvieae has emerged as an important zoonotic pathogen. However, information regarding mechanisms and factors related to its pathogenicity is lacking. In the present study, we investigated the distribution and functionality of genes related to virulence factors in L. garvieae strains isolated from different niches (diseased fish, humans, meat and dairy products, vegetables), using both post-genomic and genotypic analysis. Putative genes encoding hemolysin, fibronectin-binding protein, and penicillin acylase were detected in all analyzed genomes/strains. Their expression was significantly induced by bile salt stress. Putative genes encoding bile salt hydrolase were found in a few strains from dairy and human sources, as well as the mobilizable tet genes. Finally, all genomes possessed a folate gene cluster, in which mutations in the dihydropteroate synthase gene (folP) could be related to sulfonamide resistance. To the best of our knowledge, this is the first study aimed to explore the pathogenic potential of L. garvieae through the analysis of numerous L. garvieae genomes/strains, coming from different sources. This approach allowed the detection of virulence-related genes not yet investigated in the species and the study of their expression after exposure to different environmental stresses. The results obtained suggest a virulence potential in some L. garvieae strains that can be exploited for survival in the human gastrointestinal tract.

show abstract

Genetic investigation within Lactococcus garvieae revealed two genomic lineages

Cited by 30 publications

References 21 publications

Characterization of prophages of Lactococcus garvieae

Characterization of prophages of Lactococcus garvieae

A Virulent Phage Infecting Lactococcus garvieae, with Homology to Lactococcus lactis Phages

Detection of virulence-related genes in Lactococcus garvieae and their expression in response to different conditions

Contact Info

Product

Resources

About