What are the mechanisms of bacterial resistance?

What are the mechanisms of bacterial resistance?

The three fundamental mechanisms of antimicrobial resistance are (1) enzymatic degradation of antibacterial drugs, (2) alteration of bacterial proteins that are antimicrobial targets, and (3) changes in membrane permeability to antibiotics.

What were the four mechanisms of antibiotic action?

The biochemical resistance mechanisms used by bacteria include the following: antibiotic inactivation, target modification, altered permeability, and “bypass” of metabolic pathway.

What are the six mechanisms of action of antibiotics?

There are six major modes of action: (1) interference with cell wall synthesis, (2) inhibition of protein synthesis, (3) interference with nucleic acid synthesis, (4) inhibition of a metabolic pathway, (5) inhibition of membrane function, (6) inhibition of ATP Synthase (Fig.

What are the five mechanisms of antibiotic resistance?

Acquired antimicrobial resistance generally can be ascribed to one of five mechanisms. These are production of drug-inactivating enzymes, modification of an existing target, acquisition of a target by-pass system, reduced cell permeability and drug removal from the cell.

What is meant by inducible clindamycin resistance?

Inducible resistance to clindamycin was defined as blunting of the clear circular area of no growth around the clindamycin disk on the side adjacent to the erythromycin disk and was designated D-test positive.

What is the principle of D test?

D test is a simple disc diffusion test giving high throughput results. It is used to study the macrolide lincosamide streptogramin resistance (MLSB), both constitutive and inducible as well as macrolide streptogramin resistance (MSB) in Staphylococcus aureus.

What is the mode of action of clindamycin?

Clindamycin works primarily by binding to the 50s ribosomal subunit of bacteria. This agent disrupts protein synthesis by interfering with the transpeptidation reaction, which thereby inhibits early chain elongation.

What is D test positive?

A positive D test (see Figure) indicates the presence of macrolide-inducible resistance to clindamycin produced by an inducible methylase that alters the common ribosomal binding site for macrolides, clindamycin and the group B streptogrammins (quinupristin) (Woods, 2009) .

What is the Kirby Bauer method in susceptibility testing?

The Kirby-Bauer disk diffusion susceptibility test determines the sensitivity or resistance of pathogenic bacteria to various antimicrobial compounds in order to assist physicians in selecting treatment options their patients.

  • October 7, 2022