Proteomic profile of multidrug-resistant Serratia marcescens under meropenem challenge

Area of Science:

• Microbiology
• Proteomics
• Infectious Diseases

Background:

• Serratia marcescens is an opportunistic pathogen causing significant nosocomial infections, particularly in Intensive Care Units (ICUs) and Neonatal Intensive Care Units (NICUs).
• This bacterium exhibits resistance to multiple antimicrobial agents and possesses virulence factors contributing to its pathogenicity.
• Understanding the adaptive mechanisms of multidrug-resistant (MDR) S. marcescens is crucial for combating hospital-acquired infections.

Purpose of the Study:

• To investigate the proteomic changes in a multidrug-resistant Serratia marcescens clinical isolate following exposure to the antimicrobial meropenem.
• To elucidate the relationship between protein expression profiles and bacterial pathogenicity under antimicrobial pressure.

Main Methods:

• Proteomic analysis of a multidrug-resistant S. marcescens clinical isolate.
• Exposure of the isolate to meropenem.
• Protein identification and quantification using liquid chromatography coupled with tandem mass spectrometry (LC-MS^E).

Main Results:

• A total of 199 proteins were identified as being induced by meropenem challenge.
• Meropenem exposure led to an increase in proteins associated with energy metabolism and efflux pump activity.
• Conversely, proteins involved in oxidative stress response and bacterial cell mobility were decreased.

Conclusions:

• Meropenem challenge induces significant proteomic alterations in multidrug-resistant Serratia marcescens.
• The observed changes suggest an adaptive response involving enhanced defense mechanisms (efflux pumps, energy metabolism) and reduced susceptibility to cellular damage and motility.
• These findings provide insights into the molecular mechanisms underlying antimicrobial resistance and pathogenicity in S. marcescens infections.