Antibacterial Strategies Against Methicillin-Resistant Staphylococcus aureus

Methicillin-Resistant Staphylococcus aureus (MRSA) remains a formidable global pathogen owing to its capacity for rapid evolution of antibiotic resistance and its role in both hospital- and community-acquired infections. Contemporary strategies to curb MRSA encompass the optimisation of existing antibiotics, the repurposing of approved drugs with unanticipated antimicrobial activity, the design of novel synthetic molecules targeting unique bacterial pathways, and non-antibiotic approaches such as natural products and metal-based complexes. Emphasis has shifted towards agents that can penetrate biofilms, eradicate intracellular reservoirs and delay resistance development. Topical formulations for skin and soft tissue infections offer localised high concentrations with reduced systemic toxicity, while systemic agents aim to attenuate invasive disease. Integrative approaches, combining conventional antibiotics with adjuvants that disrupt resistance mechanisms or host–pathogen interactions, are advancing in preclinical and clinical settings. Collectively, these multifaceted strategies aim to restore therapeutic efficacy against MRSA and to prolong the lifespan of existing and emerging antibacterials.

Research from Nature Portfolio

Researchers have demonstrated that auranofin, originally an anti-rheumatic agent, exerts potent bactericidal effects against MRSA by inhibiting multiple biosynthetic pathways including cell-wall synthesis, DNA replication and protein production. Beyond its extracellular action, this repurposed compound eradicates intracellular MRSA within macrophages and reduces bacterial loads in murine systemic infection models, highlighting drug repurposing as a time-efficient strategy for addressing resistance. Complementing this approach, a series of lawsone-derived naphthoquinone compounds have been developed with enhanced lipophilicity to target MRSA. These synthetic derivatives inflict bacterial membrane damage, chelate intracellular iron and generate reactive oxygen species, yielding rapid bactericidal activity in wound-infection models and demonstrating efficacy in both cutaneous and systemic murine studies. Further, investigation of ebselen, an organoselenium compound, has revealed its capacity to inhibit thioredoxin reductase, disrupt redox homeostasis and attenuate inflammation in topical models of multidrug-resistant staphylococcal skin infection, supporting its advancement as a topical therapeutic.

Antibacterial Strategies Against Methicillin-Resistant Staphylococcus aureus publication trend

The graph below shows the total number of articles in antibacterial strategies against methicillin-resistant staphylococcus aureus across all publications each year (not limited to Nature Index journals).

Technical terms

MRSA: A strain of Staphylococcus aureus resistant to methicillin and related β-lactam antibiotics, often associated with severe community and healthcare infections.

Small colony variants (SCVs): A slow-growing subpopulation of bacteria characterised by atypical metabolic activity, enhanced biofilm formation and increased intracellular persistence, contributing to chronic and recurrent infections.

Biofilm: A structured community of bacteria encased within a self-produced polymeric matrix adherent to surfaces, which confers protection against antibiotics and host defences.

Minimum inhibitory concentration (MIC): The lowest concentration of an antimicrobial agent required to prevent visible growth of a microorganism in vitro, guiding dose selection and susceptibility assessment.

References

1. Antibacterial activity and mechanism of action of auranofin against multi-drug resistant bacterial pathogens. Scientific Reports (2016).
2. Naphthoquinone-derivative as a synthetic compound to overcome the antibiotic resistance of methicillin-resistant S. aureus. Communications Biology (2020).
3. Repurposing ebselen for treatment of multidrug-resistant staphylococcal infections. Scientific Reports (2015).
4. Manuka honey as a non-antibiotic alternative against Staphylococcus spp. and their small colony variant (SCVs) phenotypes. Frontiers in Cellular and Infection Microbiology (2024).
5. Harnessing the Dual Antimicrobial Mechanism of Action with Fe(8-Hydroxyquinoline)3 to Develop a Topical Ointment for Mupirocin-Resistant MRSA Infections. Antibiotics (2023).