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Modes and mechanism of action of antibiotics

MODES/MECHANISM OF ACTION Antibiotics work through many modes or mechanisms of action that disrupt the structure and/or function of the bacteria. The structure of a typical bacteria will have a plasma membrane and a cell wall. All bacteria will have their DNA in the form of a single circular chromosome. Within the bacteria cell DNA is replicated for cell division (binary fission), DNA is transcribed into mRNA that will travel to ribosomes where it gets translated into proteins. Let's look at some modes of action that antibiotics use to combat bacteria. There are 5 basic mechanisms or "modes of action" used by antibiotics: 1. Inhibition of Cell Wall Synthesis 2. Inhibition of Protein Synthesis 3. Interference with Membrane Functionality 4. Inhibition of Nucleic Acid Synthesis 5. Inhibition of Metabolic Pathways 1. INHIBITION OF CEL WALL SYNTHESIS The most popular mode of action used by antibiotics is inhibition of cell wall synthesis. There are 4 Classes o...
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Bactericidal vs Bacteriostatic Antibiotics Antibiotics will function to either: 1. Destroy or Kill Bacteria - Antibiotics that destroy or kill bacteria are called bactericidal. 2. Stop or Slow Down Bacterial Growth. - Antibiotics that halt or slow the growth of bacteria are called bacteriostatic. The Major Categories of Antibiotics  Narrow-Spectrum Antibiotics - These antibiotics function to control the growth of only a narrow range of microorganisms.  Broad-Spectrum Antibiotics - These antibiotics function to control the growth of very large ranges of microorganisms.Selective Toxicity Let's think about the idea of antibiotics for a minute. When a person has a bacterial infection, the bacteria are alive. We want to kill the bacteria, but not the host! It is also a good idea not to kill off too many of the "good" bacteria living inside that person either. So we need the antibiotic to be selectively toxic.  An antibiotic or antimicrobial drug that exhibits ...
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CONTROL OF MICROORGANISM BY ANTIBIOTICS

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CONTROL OF MICROORGANISM BY ANTIBIOTICS Control of microorganisms is essential in order to prevent the transmission of diseases And infection, stop decomposition and spoilage, and prevent unwanted microbial contamination. Microorganisms are controlled by means of physical agents and chemical agents. Physical agents include such methods of control as high or low temperature, desiccation, osmotic pressure, radiation, and filtration. Control by chemical agents refers to the use of disinfectants, antiseptics, antibiotics, and chemotherapeutic antimicrobial chemicals. ANTIBIOTICS The first antibiotic was discovered, quite by accident, by bacteriologist named Alexander Fleming in 1928. Alexander Fleming had been studying bacteria using Petri dishes, and left some unwashed Petri dishes piled high in a sink with Lysol. Some of the dishes were submerged in the Lysol disinfectant and some were not, because they were located high on top of the dish pile.  When Alexander Fleming re...
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