Transfer of a lincomycin-resistant plasmid between coagulase-negative staphylococci during soybean fermentation and mouse intestine passage

Abstract

Staphylococcus equorum is a benign bacterium and the predominant species in high-salt fermented food. Some strains of S. equorum contain antibiotic-resistance plasmids, such as pSELNU1 that contains a lincosamide nucleotidyltransferase (lnuA) gene and confers resistance to lincomycin. Previously, we showed that pSELNU1 is transferred to other bacteria under laboratory growth conditions. However, it is not known if the plasmid can be transferred to other bacteria during food fermentation (in situ) or during passage through animal intestines (in vivo). In this study, we examined the in situ and in vivo transfer of pSELNU1 using Staphylococcus saprophyticus as a recipient. During soybean fermentation, pSELNU1 was transferred to S. saprophyticus at a rate of 1.9 × 10−5–5.6 × 10−6 per recipient in the presence of lincomycin. However, during passage through murine intestines, the plasmid was transferred at similar rates (1.3 × 10−5 per recipient) in the absence of lincomycin, indicating that the plasmid transfer is much more efficient under in vivo conditions. Based on these results, we conclude that it is prudent to examine food fermentation starter candidates for the presence of mobile genetic elements containing antibiotic resistance genes and to select candidates lacking these genes.

Functional Annotation Genome Unravels Potential Probiotic Bacillus velezensis Strain KMU01 from Traditional Korean Fermented Kimchi

“…Antibiotic resistance can indirectly increase virulence, not directly, via quorum sensing [ 34 ]. Furthermore, acquired antibiotic resistance genes may be transferred to other bacteria during fermentation and intestinal commensal bacteria as they pass through the intestine [ 35 , 36 ]. Therefore, it is essential to check for the presence of transferrable antibiotic resistance genes.…”

Novel Starter Strain Enterococcus faecium DMEA09 from Traditional Korean Fermented Meju

“…Furthermore, antibiotic resistance genes can be transferred to other bacteria during fermentation. They can also be transferred to intestinal commensal bacteria as they pass through the intestine [ 52 , 53 ]. Therefore, it is essential to check for the presence of acquired antibiotic resistance genes.…”

Staphylococcus equorum plasmid pKS1030-3 encodes auxiliary biofilm formation and trans-acting gene mobilization systems

“…Here, plasmid pKS1030-3 from S. equorum KS1030 was used in assessment of gene transferability and biofilm formation. In gene transfer experiments, S. saprophyticus KM1053 was used as the recipient strain because it is resistant to tetracycline 11 . S. aureus RN4220 was used as an expression host for constructed plasmids.…”

“…The lnuA gene was located on small plasmids, named pSELNU1–3, with only two different nucleotide sequences among these three plasmids 10 . Notably, although pSELNU1 is not a conjugative plasmid, pSELNU1 in S. equorum strain KS1030 was transferred to other Staphylococcus species, Enterococcus faecalis , and Tetragenococcus halophilus in vitro 10 , and was also transferred to S. saprophyticus during soybean fermentation (in situ) and passage through murine intestines (in vivo) under lincomycin pressure 11 . Recent complete genome sequencing revealed that S. equorum KS1030 also harbours plasmid pKS1030-3, which encodes elements facilitating gene mobility such as a relaxase 12 .…”