Antibiotic Resistance

Only available on StudyMode
  • Download(s) : 50
  • Published : May 15, 2013
Open Document
Text Preview
My research shows the rise in antibiotic resistant pathogens through horizontal gene transfer. Located in the bacteria are plasmids. They are independent, self-duplicating, and allow bacteria to perform new functions/generate new products. Basically plasmids help their hosts to stop the action of antibiotics and become resistant. “Gene transfer must be integral and critical to the overall survival of bacteria, providing a way for them to adapt to difficult conditions” (Levy 2002, 83). Horizontal gene transfer can occur through conjugation, transposition, transduction, and transformation. These forms of horizontal gene transfer have led to several ways for antibiotic resistant genes to be obtained. The acquiring of these resistant genes allow bacteria to stop the function of antibiotics. Conjugation is a physical bridge between two bacteria that has cell-to-cell contact. The bacterium produces a fine filamentous protein called a “pilus” (Levy 2002, 83). The pilus brings the donor bacterium and the accepting bacterium together. The donor bacterium then makes a duplicate of its resistance plasmid and gives the copy to the accepting bacterium. Conjugation can also occur when small plasmids that do not have the ability to direct their own transfer ride on the backs of larger plasmids in order to enter a new bacterium. Another form of a mating system is the use of sex pheromones. Pheromones are substances secreted by bacteria that attract two different cells to attach together. Closely attached bacteria can exchange whole plasmids or pieces of plasmids. Bacteria can exchange resistant genes without having their plasmid remain in the cell they exchanged with. This is transposition; small segments of DNA called transposons can jump from one piece of DNA to another. Transposons do not rely on any sort of host cell in order to survive and multiply. Professor Ruth Hall from Australia was first to discover integrin, a new kind of transposon. An integrin “acts like a...
tracking img