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What is multiple drug resistance (MDR)?

Multiple drug resistance is the condition of a cell that enables to resist against distinct drugs or chemicals.

What is drug resistance?

Loss of effectiveness of drugs on the patient’s body in curing from a disease. Pathogens are responsible to neutralize the effect of drugs mainly microorganisms. What are antibiotics? Substance produced by a microorganism that is antagonistic to the growth of other microorganisms.

What are the mechanisms of drug resistance in the cells?

Following mechanisms can be involved-- Drug target unchanged Resistance by exclusion loss of drug accumulation mechanism (decreased import) increased drug elimination (increases export) (e.g. multidrug resistance in cancer cells) Resistance by metabolism active drug converted to an inactive form (e.g. penicillinase, insecticide resistance) prodrug no longer converted to its active form (e.g. resistance to purine analogues in cancer cells) b. Alterations in drug target elimination of target (e.g. induction of alternative pathway) alteration of targets' affinity for the drug overproduction of target (e.g. gene amplification) accumulation of metabolite antagonistic to drug (e.g. PABA overproduction by pneumococci)

What is MRSA (methicillin-resistant Staphylococcus aureus)?

Some staph bacteria are resistant to antibiotics. MRSA is a type of staph that is resistant to antibiotics called beta-lactams. Beta-lactam antibiotics include methicillin and other more common antibiotics such as oxacillin, penicillin and amoxicillin. While 25% to 30% of the population is colonized with staph, approximately 1% is colonized with MRSA.

What are efflux pumps in microbiology?

Efflux pumps are proteinaceous transporters localized in the cytoplasmic membrane of all kinds of cells. They are active transporters meaning that they require a source of chemical energy to perform their function. Some are primary active transporters utilizing Adenosine triphosphate hydrolysis as a source of energy, while others are secondary active transporters (uniporters, symporters or antiporters) in which transport is coupled to an electrochemical potential difference created by pumping out hydrogen or sodium ions outside the cell. Bacterial efflux transporters are classified into five major superfamilies, based on the amino acid sequence and the energy source used to export their substrates: The major facilitator superfamily (MFS) The ATP-binding cassette superfamily (ABC) The small multidrug resistance family (SMR) The resistance-nodulation-cell division superfamily (RND) The multidrug and toxic compound extrusion family (MATE)