Index >> Microbial Products Influencing Plant Growth >> Resistance to Antiobiotics

Resistance to antibiotics
Resistance to antibiotics may be intrinsic (inherent) or acquired. Prior to the use of antibiotics, inherent or intrinsic resistance was common whereas acquired resistance is a result of exposure to these agents. Acquired resis­tance may be the result of spontaneous chromosomal mutations or due to entry of plasmids with resistance factors (R factors) and transposons. The resistance genes may be transferred to plasmids from chromosomes and vice versa by recombination (exchanges of DNA pieces) in the presence of a recA gene showing genetic homology. Transposons are also pieces of DNA that carry resistance genes. They are known as 'jumping genes' and can get inserted into chromosomes or plasmids even if homology does not exist and this process is independent of a recA gene.