Nowadays, antibiotic resistance constitutes one of the world-wide health crisis, food security and development. This review was designed to highlight the resistance mechanisms in Pseudomonas aeruginosa, a multi-resistant bacterium, and to propose strategies to combat antibiotic resistance. P. aeruginosa is a Gram-negative bacillus, strict aerobic and non fermentative. It is involved in opportunistic infections, mainly in a nosocomial context. This bacterium is characterized by a natural resistance to many antibiotics, limiting the number of effective therapies. Acquisition of resistance to β-lactams is common and results from mutations leading to overproduction of chromosomal cephalosporinase (class C β-lactamase), overexpression of active efflux systems, decreased membrane permeability and/or of the acquisition of transferable genes. Resistance to aminoglycosides is common and most often the result of the acquisition of genes for modifying enzymes. Resistance to fluoroquinolones is frequently linked to mutations in genes encoding deoxyribonucleic acid (DNA) gyrase. Overexpression of efflux pumps also contributes to resistance to aminoglycosides and fluoroquinolones. A new molecule, ceftolozane-tazobactam, appears promising, particularly in the treatment of P. aeruginosa infections overproducing the cephalosporinase AmpC. However, multi-resistant or toto-resistant strains are being described more and more frequently throughout the world. The formation of biofilm controlled by the quorum sensing enhances the antibiotic resistance in P. aeruginosa. The increase of the antibiotic resistance in P. aeruginosa is a worrying phenomenon and biologists must be aware. New promising strategies must be developed for combating P. aeruginosa drug resistance.

Antibiotic resistance, Biofilm, Quorum sensing, Pseudomonas aeruginosa