Genetics of Antimicrobial Resistance

Abstract

Antimicrobial resistant strains of bacteria are an increasing threat to animal and human health. Resistance mechanisms to circumvent the toxic action of antimicrobials have been identified and described for all known antimicrobials currently available for clinical use in human and veterinary medicine. Acquired bacterial antibiotic resistance can result from the mutation of normal cellular genes, the acquisition of foreign resistance genes, or a combination of these two mechanisms. The most common resistance mechanisms employed by bacteria include enzymatic degradation or alteration of the antimicrobial, mutation in the antimicrobial target site, decreased cell wall permeability to antimicrobials, and active efflux of the antimicrobial across the cell membrane. The spread of mobile genetic elements such as plasmids, transposons, and integrons has greatly contributed to the rapid dissemination of antimicrobial resistance among several bacterial genera of human and veterinary importance. Antimicrobial resistance genes have been shown to accumulate on mobile elements, leading to a situation where multidrug resistance phenotypes can be transferred to a susceptible recipient via a single genetic event. The increasing prevalence of antimicrobial resistant bacterial pathogens has severe implications for the future treatment and prevention of infectious diseases in both animals and humans. The versatility with which bacteria adapt to their environment and exchange DNA between different genera highlights the need to implement effective antimicrobial stewardship and infection control programs in both human and veterinary medicine.

Antimicrobial, Antiviral Activity and GC-MS Analysis of Essential Oil Extracted from Achillea fragrantissima Plant Growing In Sinai Peninsula, Egypt

“…Although, the pharmacological companies have produced a number of new antibiotics recently, but even then microorganism resistance to antibiotics increased throughout the world [5,7]. This situation has attract attention of researchers towards herbal products for developing and improve the antibacterial drugs quality [6,7].…”

“…Although, the pharmacological companies have produced a number of new antibiotics recently, but even then microorganism resistance to antibiotics increased throughout the world [5,7]. This situation has attract attention of researchers towards herbal products for developing and improve the antibacterial drugs quality [6,7].Natural products of higher plants may possess a new source of antimicrobial agents with possibly novel mechanisms for treatment of infectious diseases [8,9]. Medicinal plants contain active principles which can be used as alternative effective herbal drugs against common bacterial infections [10].…”

Studies on avian pathogenic Escherichia coli in commercial broiler chicken in South East Queensland

“…Antimicrobial resistance is defined as the bacteria's ability to survive and/or grow in the presence of a chemical (drug) that would normally kill them or inhibit their growth (Harbottle et al, 2006). The genetic flexibility of bacteria enables them to adapt, evolve and survive in their environment by developing different resistance mechanisms (Acar et al, 2012).…”

“…Horizontal gene transfer is the most important mechanism increasing resistance and is due to the transfer of genes among different bacterial strains and/or species. Horizontal gene transfer occurs mainly through conjugation and MGE (Allen et al, 2013;Boerlin and White, 2013;Davies, 1994;Harbottle et al, 2006).…”

Antimicrobial potentiality of Polyalthia longifolia seed oil against multi drug resistant (MDR) strains of bacteria and fungus of clinical origin

“…Since the discovery of these antibiotics and their uses as chemotherapeutic agents, there has been a belief in the medical group that this would lead to the eventual eradication of infectious diseases. However, overuse of antibiotics has become the major factor for the emergence and dissemination of multi-drug resistant (MDR) strains of several groups of microorganisms (Harbottle et al, 2006). The worldwide emergence of Escherichia coli, Klebsiella pneumoniae, Haemophilus and many other β-lactamase producers has become a major therapeutic problem.…”