By characterizing the trajectories of antibiotic resistance gene transfer in bacterial communities such as the gut microbiome, we will better understand the factors that influence this spread of resistance. Our aim was to investigate the host network of a multi-drug resistance broad-host-range plasmid in the culturable gut microbiome of zebrafish.
In separate matings between the same donor and four prominent isolates from the gut microbiome, the plasmid transferred to two of these four isolates, A. veronii and Plesiomonas shigelloides, but not to Shewanella putrefaciens and Vibrio mimicus When these A. veronii and P. shigelloides transconjugants were the donors in matings with the same four isolates, the plasmid now also transferred from A. veronii to S. putrefaciens P. shigelloides was unable to donate the plasmid and V. mimicus was unable to acquire it.
It also suggests that rare gut microbiome members should not be ignored as potential reservoirs of multi-drug resistance plasmids from food.
Plasmid profiles and antibiotic susceptibility patterns of bacteria isolated from abattoirs wastewater within Ilorin, Kwara, Nigeria
Background and objectives: Waste water from abattoirs could harbour bacteria some of which are pathogenic. Therefore, this study aimed to assess the quality of wastewater from some abattoirs in Ilorin, Nigeria.
Materials and methods: The counts of viable bacteria, total coliform, faecal coliform, enterococci, S. aureus, P. aeruginosa and Salmonella/Shigella spp. of the wastewater was determined using selective media.
The sanitary condition appraisal, antibiotic susceptibility test and plasmid profile of the isolates were assessed using standard methods.
Results: The highest count of viable bacteria and total coliform obtained were 9.0 × 107 and 3.0 × 107 CFU/ml respectively.
Faecal coliform and enterococcal count had the same highest value of 3.0 × 105 CFU/ml. The highest count of pathogenic bacteria: Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella spp. were 2.5 × 108, 1.9 × 107 and 3.0 × 104 CFU/ml respectively. The abattoirs sanitary scores ranged from 28.6-57.1%. The isolates showed multiple antibiotic resistance (MAR) index ranging from 0.5-1.0. Plasmid curing with 0.1 mg/ml of acridine orange solution led to a reduction in the MAR index of most of the Gram-negative bacteria. Pseudomonas stutzeri was susceptible to all the antibiotics while Proteus Vulgaris was resistant to all the antibiotics after curing.
Most of the Gram-negative bacteria isolated belong to the families Enterobacteriaceae and Pseudomonadaceae while the Gram-positive bacteria belong to the families Staphylococcaceae, Enterococcaceae, and Streptococcaceae.
Conclusion: It was concluded from this study that wastewaters from the abattoirs were contaminated by bacteria with a high MAR index. Most of these bacteria borne their antibiotic-resistant factors in their plasmid.