An Overview of Mechanisms and Emergence of Antimicrobials Drug Resistance

Received: Revised: Accepted: 2013–09–16 2013–10–24 2013–10–24 Emergence of antimicrobial drug resistance in bacteria is widely explored but still ill understood. Antibiotic resistance is a complex phenomenon due to multiple ways of its acquisition, mechanism of action and spread. Antibiotic resistance may be innate, present in microbes due to their inherent inbuilt metabolic and structural components. Other type of innate resistance is one which has been detected in strains isolated even before the era of the use of any antibiotics and often specific with bacterium. The most important and problematic is the acquired drug resistance. It spread rapidly with the use of antimicrobials in one or other realm of ecosystem. Inactivation of antimicrobials occurs by some common mechanism such as drug inactivation/degradation by bacterial enzymes or alteration in the bacterial targets or expulsion of drug out of the bacterial cells (efflux) or by preventing the entry of drug into bacterium. Here some important aspects of mechanism of antimicrobial drug resistance and its emergence are discussed.