ORCID
0000-0002-5812-9013
Department
Biological Sciences
Year of Study
1
Full-time or Part-time Study
Full-time
Level
Postgraduate
Presentation Type
Poster
Supervisor
Dr Craig Murphy
Supervisor
Dr. Eamonn Culligan
Abstract
Background
Resistance to antibiotics make Staphylococcus aureus infections notoriously hard to treat. The emergence of antibiotic resistant strains such as MRSA, and the ability to form robust biofilms provide protection against antibiotics and host immune responses. Significantly, more than 80 % of bacterial infections are biofilm mediated. The goal of this study was to evaluate the antimicrobial potential of isolates from marine environments against MRSA and four clinical S. aureus strains in terms of biofilm inhibition and eradication.
Method
A large bank of salt water bacterial isolates was cultured in glucose-supplemented trypticase soy broth (TSBg) and resulting colonies were screened against S. aureus strains. Bacterial isolates of interest were further examined for bactericidal and antibiofilm activity.
All bacterial strains and bacterial isolates were standardised using McFarland standards. The minimum biofilm inhibitory and eradication concentrations (MBIC and MBEC) was measured using a crystal violet staining assay. Bacterial viability in biofilms was determined as the reduction [%] in metabolic activity determined by the 2,3,5-triphenyltetrazolium chloride (TTC) assay.
Results
The obtained results suggest that one of the saltwater isolates analysed reduced the ability of all the S. aureus strains tested to form biofilm. MBIC was achieved at an isolate concentration of 3x104 CFU/mL. A reduction in preformed biofilms was also observed across all S. aureus strains, however, this was strain specific.
Conclusion
Selected saltwater bacterial isolates have demonstrated inhibitory potential against biofilm-forming S. aureus strains. However, further investigation is needed to characterise and improve their activity against mature biofilms.
Keywords:
S. aureus, Biofilm Inhibition, Biofilm Eradication
Start Date
June 2022
End Date
June 2022
Recommended Citation
Murphy, Monica, "Investigating the antibiofilm properties of saltwater isolates against methicillin-resistant Staphylococcus aureus and clinical Staphylococcal strains" (2022). ORBioM (Open Research BioSciences Meeting). 2.
https://sword.cit.ie/orbiom/2022/posters/2
Investigating the antibiofilm properties of saltwater isolates against methicillin-resistant Staphylococcus aureus and clinical Staphylococcal strains
Background
Resistance to antibiotics make Staphylococcus aureus infections notoriously hard to treat. The emergence of antibiotic resistant strains such as MRSA, and the ability to form robust biofilms provide protection against antibiotics and host immune responses. Significantly, more than 80 % of bacterial infections are biofilm mediated. The goal of this study was to evaluate the antimicrobial potential of isolates from marine environments against MRSA and four clinical S. aureus strains in terms of biofilm inhibition and eradication.
Method
A large bank of salt water bacterial isolates was cultured in glucose-supplemented trypticase soy broth (TSBg) and resulting colonies were screened against S. aureus strains. Bacterial isolates of interest were further examined for bactericidal and antibiofilm activity.
All bacterial strains and bacterial isolates were standardised using McFarland standards. The minimum biofilm inhibitory and eradication concentrations (MBIC and MBEC) was measured using a crystal violet staining assay. Bacterial viability in biofilms was determined as the reduction [%] in metabolic activity determined by the 2,3,5-triphenyltetrazolium chloride (TTC) assay.
Results
The obtained results suggest that one of the saltwater isolates analysed reduced the ability of all the S. aureus strains tested to form biofilm. MBIC was achieved at an isolate concentration of 3x104 CFU/mL. A reduction in preformed biofilms was also observed across all S. aureus strains, however, this was strain specific.
Conclusion
Selected saltwater bacterial isolates have demonstrated inhibitory potential against biofilm-forming S. aureus strains. However, further investigation is needed to characterise and improve their activity against mature biofilms.