Penicillin is a group of antibiotics derived from the fungus Penicillium. It was the first antibiotic discovered and has been instrumental in combating bacterial infections. Penicillin is highly effective against bacteria like Staphylococci, Clostridia, and Streptococci, making it one of the most widely used antibiotics in medical history. It is commonly used to treat bacterial infections of the ear, nose, throat, and skin, as well as diseases like pneumonia and scarlet fever. Penicillin works by inhibiting the formation of bacterial cell walls, ultimately destroying the bacteria. Its discovery marked a significant breakthrough in modern medicine, saving countless lives.
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Laws of Motion
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Introduction to Biotechnology
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Observing Space : Telescopes
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- Penicillin
- Working
- Caution
Introduction to Scientists:
In 1928, Alexander Fleming, a professor of microbiology at St. Mary’s Hospital, made a groundbreaking discovery while studying bacterial and fungal cultures in Petri dishes. On 3rd September 1928, Fleming noticed something unusual in one of the dishes containing staphylococci bacteria.
A fungus, identified as Penicillium, had grown in the dish, and the area around the fungal colonies was clear, indicating that the bacteria had been destroyed. After further research, Fleming confirmed that the substance secreted by the fungus was capable of killing bacteria. This accidental observation led to the discovery of penicillin, the first antibiotic, which became a cornerstone in the treatment of bacterial infections and paved the way for cures for many previously incurable diseases.
Dr. Alexander Fleming
Penicillin:
Working:
Penicillin works by targeting the bacterial cell wall, which is essential for the survival and reproduction of bacteria.
- Penicillin interferes with the production of peptidoglycan, a key component of the bacterial cell wall.
- It binds to and inhibits enzymes known as penicillin-binding proteins (PBPs) that are crucial for cross-linking peptidoglycan strands.
- Without proper cross-linking, the bacterial cell wall becomes weak and unable to maintain structural integrity.
- As a result of the weakened cell wall, bacteria cannot withstand osmotic pressure and burst (lyse), leading to their death.
- Penicillin specifically targets bacteria without harming human cells, as human cells lack peptidoglycan and PBPs.
This mechanism makes penicillin highly effective against actively growing and dividing bacteria, particularly Gram-positive bacteria like Streptococcus and Staphylococcus. However, some bacteria have developed resistance by producing beta-lactamase enzymes, which break down penicillin's structure.
Caution:
- Antibiotics should be taken strictly when prescribed by a qualified doctor.
- Do not buy antibiotics from a medical store without a valid prescription, as misuse can lead to serious health issues.
- Avoid using antibiotics on your own for common illnesses like throat infections, colds, or influenza, as these are often caused by viruses, not bacteria.
- Even if you feel better before finishing the prescribed antibiotic course, you must complete it to ensure the infection is fully treated.
- Never suggest antibiotics that worked for you to others, as their condition may require a different treatment.
- Misusing antibiotics can lead to resistance, where bacteria become immune, making future infections harder to treat.
- Take the antibiotic exactly as prescribed, including the correct dosage and duration, to ensure its effectiveness.
- Keep antibiotics in a safe place away from children and at the recommended temperature to preserve their potency.
- Report any unusual side effects to your doctor immediately for appropriate guidance.
- Using antibiotics unnecessarily or too frequently weakens their effectiveness for treating bacterial infections in the long term.
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