Characterization of Lactococcus garvieae isolated from radish and broccoli sprouts that exhibited a KG⁺phenotype, lack of virulence and absence of a capsule

Abstract

Aims: To identify Lactococcus garvieae isolates from radish and broccoli sprouts and compare them with virulent and less virulent mutant strains obtained from yellowtails with regard to KG phenotype, presence of a capsule and virulence towards yellowtails and mice. Methods and Results: Comparative 16S rRNA gene sequence analysis of six isolates obtained from radish and broccoli sprouts indicated that they were L. garvieae (similarity >99%). They were compared with KG9502, Lg2 and ATCC49156 strains obtained from yellowtails. A less virulent mutant strain Lg2‐S was obtained by Lg2 subculture. Biochemical characterization of the six strains resembled that of KG9502, Lg2, ATCC49156 and Lg2‐S, except for saccharose and tagatose acidification and the presence of hippuricase. These six strains were nonpathogenic towards yellowtails and mice, nonsusceptible to bacteriophages and demonstrated heterogeneity on pulsed‐field gel electrophoresis analysis. Using transmission electron microscopy, a capsule was observed in KG9502 and Lg2 but not in ATCC49156 and Lg2‐S. Conclusions: We isolated L. garvieae strains that lacked pathogenicity towards yellowtails and mice from radish and broccoli sprouts; these were noncapsulated and exhibited KG+ phenotype. Significance and Impact of the Study: This is the first documentation of L. garvieae isolated from terrestrial plants. These isolates exhibited genetic diversity; however, they were noncapsulated and nonpathogenic towards yellowtails and mice.

Garvicin A, a Novel Class IId Bacteriocin from Lactococcus garvieae That Inhibits Septum Formation in L. garvieae Strains

“…In fact, L. garvieae is currently considered a potential emerging zoonotic pathogen (10). In addition, this microorganism is widespread in the environment, having been isolated from wild birds, rivers, sewage waters, and a wide variety of foodstuffs, including vegetables, meat, sausages, and, particularly, artisan dairy products (11)(12)(13).…”

The Sensitivity of PCR to the Number of Lactococcus garvieae in Different Concentrations of NaCl: FTA Technique

“…It is isolated from buffalos with mastitis (Teixeira et al, 1996) and clinical specimens of human blood, urine, and skin (Vinh et al, 2006;Wang, 2007;Villani et al, 2001). Moreover, L. garvieae is isolated from various kinds of food products including cow's milk (Villani et al, 2001), cheeses (Alegr´ıa et al, 2009;Fortina et al, 2007;El-Baradei et al, 2007;Florez & Mayo, 2006), meat products (Aquilanti et al, 2007;Barakat et al, 2000;Rantsiou et al, 2005) and sprout (Kawanishi et al, 2007). L. garvieae is detected in most of Egyptian cheeses (El-Baradei et al, 2005) and also found in Jordanian cheese (Alrabadi, 2009).…”

A Transferable 20-Kilobase Multiple Drug Resistance-Conferring R Plasmid (pKL0018) from a Fish Pathogen ( Lactococcus garvieae ) Is Highly Homologous to a Conjugative Multiple Drug Resistance-Conferring Enterococcal Plasmid

“…Moreover, the yellowtail-derived L. garvieae isolates appeared to be homogenous and very different from isolates obtained from other fish, terrestrial animals, and food plants (4,5,6). Recently, of 146 L. garvieae strains isolated from 1999 to 2006 from yellowtail farms in three prefectures in Japan, 46 strains had high levels of resistance to EM, LCM, and tetracycline and were found to be carrying transferable R plasmids that carry ermB and tetS genes, as evidenced by conjugation, Southern blotting, and PCR methods (7).…”