Explain How Penicillin Stops Bacteria Without Harming Human Cells
When a microorganism produces a substance that can kill other microorganisms, it is called antibiosis. You can compare this word to 'symbiosis,' which is when organisms live together in a way that is often mutually beneficial. The word 'antibiotic' comes from this 'antibiosis.' The antibiotic-producing mold was identified as a member of the genus Penicillium, and its antibacterial compound was eventually isolated and named penicillin. In the early 1940s, Howard Florey and Ernst Chain carried out the first clinical trials of penicillin, just in time for the drug to be used on wounded soldiers in the final stages of World War II. From that time forward, antibiotics have made a huge impact on human history and drastically reduced the infectious disease burden in the world. By now, you're probably super curious about how penicillin actually works. It turns out that penicillin interferes with the synthesis of peptidoglycan in bacterial cell walls. Remember that peptidoglycan is a complex molecule made of sugars and polypeptides that forms a tough, strong lattice that surrounds bacterial cells. Peptidoglycan is a major component of most bacterial cell walls. The rigid peptidoglycan layer helps bacteria stay intact in the face of osmotic pressure, which is when water tends to flow into or out of a cell to balance out the concentration of solutes on either side of a membrane.
This is due to several reasons, including low profitability due to short treatment cycles, lack of new therapeutic targets or strategies for killing bacterial cells, and low tolerability in the medical community for side effects.
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