Enterococcus faecalis resistance to new generation antibiotics
A very timely and important topic!
Enterococcus faecalis is a Gram-positive bacterium that is commonly found in the human gut and is a significant cause of hospital-acquired infections, including urinary tract infections, bloodstream infections, and surgical site infections. Unfortunately, E. faecalis has developed resistance to many antibiotics, including the new generation antibiotics.
Here are some of the ways E. faecalis has developed resistance to new generation antibiotics:
- β-lactamases: E. faecalis produces a variety of β-lactamases, which are enzymes that break down β-lactam antibiotics, such as penicillins and cephalosporins. These enzymes can also hydrolyze newer β-lactam antibiotics, such as carbapenems and monobactams.
- Aminoglycoside-modifying enzymes: E. faecalis produces enzymes that can modify aminoglycoside antibiotics, such as gentamicin and tobramycin, making them ineffective against the bacteria.
- Quinolone resistance: E. faecalis has developed resistance to quinolone antibiotics, such as ciprofloxacin and levofloxacin, through mutations in the DNA gyrase and topoisomerase IV genes.
- Tetracycline resistance: E. faecalis has developed resistance to tetracycline antibiotics, such as doxycycline and minocycline, through the production of efflux pumps and ribosomal protection proteins.
- Vancomycin resistance: E. faecalis has developed resistance to vancomycin, a glycopeptide antibiotic, through the production of vancomycin-resistant proteins, such as VanA and VanB.
- Daptomycin resistance: E. faecalis has developed resistance to daptomycin, a lipopeptide antibiotic, through mutations in the cell membrane and the production of efflux pumps.
- Oxacillin resistance: E. faecalis has developed resistance to oxacillin, a penicillinase-resistant penicillin, through the production of β-lactamases and the modification of the bacterial cell wall.
The mechanisms of resistance to new generation antibiotics in E. faecalis are often complex and involve multiple genetic and biochemical changes. These changes can be acquired through horizontal gene transfer, such as conjugation and transformation, or through mutations that occur spontaneously or under the selective pressure of antibiotic use.
The development of resistance to new generation antibiotics in E. faecalis is a significant concern, as it limits treatment options for patients with E. faecalis infections. Therefore, it is essential to develop new antibiotics that can effectively target E. faecalis and to implement strategies to reduce the spread of antibiotic resistance, such as improving infection control practices and promoting the responsible use of antibiotics.