Antibiotics mechanism of action on the USMLE Step 1 exam

Tyler York

Antibiotics may be bacteriostatic or bactericidal. They can be classified according to their mechanism of action. This video describes the mechanism of action of currently used antibiotics.

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Full Antibiotics mechanism of action on the USMLE Step 1 exam exam video transcript:

Hello everyone. I'm so job that I'm the founder of Gracie with Emily and he was simply altered achievable

In this video, I would like to discuss the mechanics of affection of antibiotics. Antibiotics may be back to yesterday or bactericidal.

Bactericidal antibiotics are able to kill the bacteria and they are used in very specific situations, like endocarditis life-threatening infections and infections in immunocompromised. Host, on the other hand, bacteriostatic, antibiotics are able to inhibit the growth of bacteria without killing them.

According to their mechanism of action. Antibiotics can be classified into six classes. These are antibiotics acting on the cell wall antibiotics acting on the cell membrane. Bacterial, protein synthesis, Inhibitors messenger, RNA synthesis Inhibitors antibiotics, affecting DNA, replication and antibiotics interfering with folic acid metabolism.

Cell wall synthesis inhibitor has influenza B. Talatum antibiotics like penicillin tense of Ballast Point and also vancomycin cycloserine and Bacitracin.

Penicillin. Sunset Palace points have the same mechanism of action. There is a component in the cell wall of bacteria, which is called, as d-alanine dla9, this component, normally binds to a protein called as penicillin binding protein. There are various types of penicillin binding, proteins. Have a beetle Acton bring which mimics this d l. N n d l n e.

The beetle XM ring of penicillin sensor. Power steering binds to the penicillin binding proteins, which inhibits the synthesis of peptide of lighting in the cell wall of bacteria. Not only that penicillin. Also inhibits the function of Trance peptide, Aces, and this in a b cross-linking of the bacterial cell wall.

Some patients May develop severe allergic reactions to penicillin. Some of them may have anaphylaxis.

If I was born in sin penicillins, share a cross-reactivity of about 1 to 5% for severe allergic reactions.

Glycopeptides like Vancomycin Antico planning the directly behind to the DL. In Indiana named portion of the bacterial, cell wall. And, in this way, they inhibit the pride of life in synthesis in back.

Carbapenems like Emma Penn American. A Mexican drug inhibits cell wall synthesis by binding to the penicillin binding proteins monobactams like aztreonam, also inhibits cell wall synthesis in bacteria.

Antibiotics that are active on the bacterial cell membrane include polymyxins and optimizing, which is koleston they bind to the outer membrane polysaccharides and then disrupt the outer membrane acting as cationic detergents.

Colston also has anti in 2,000 activity since it binds to an innie B, the activity of lipid a

Daptomycin is a lipopeptide antibiotic it attaches itself to the cell membrane of bacteria and then it punches holes causing leakage of irons from the outer membrane which causes cell death.

Antibiotics that inhibits bacterial protein synthesis are for the group as 30s, ribosomal subunit, in a Bitters and 50s, ribosomal subunit, inhibitors.

Aminoglycosides and tetracyclines at on the 30s ribosomal subunit, and they can be remembered by the mnemonic at 30 or 8030.

The antibiotics that act and the 50s ribosomal. Subunit, are chloramphenicol lincosamides macrolides Elena solid, and they can be remembered by the mnemonic clumsy line at 50.

Aminoglycosides in a bit protein synthesis by causing premature. Termination of mRNA in Translation by binding near the a site on the 30s. Ribosome

Aminoglycosides act synergistically with Penicillin, which lies the cell wall allowing the aminoglycoside to enter the cell and inhibit the ribosomes.

Tetracyclines and play suicide Queens like to do cycling prevent binding of Transfer RNA to be a state.

Chloramphenicol binds to an inhibitor 23s, ribosomal subunit of the 50s ribosome, does it inhibits peptidyl transferase activity? It also inhibits The Binding of TRNA to the east side.

Microwave legitimizing lincosamides like Linda myosin and streptogramins like, weenie, Preston and Alpha Christine inhibit protein synthesis by causing premature, Detachment of the incomplete peptide chain.

Linezolid, prevents the formation of the initiation complex for protein synthesis.

Colognes or bactericidal drugs, which inhibit DNA replication. They include ofloxacin, norfluoxetine, ciprofloxacin or levofloxacin exactra

Funeral homes in a DNA, replication by inhibiting, the enzyme topoisomerase for all cyclists DNA, gyrase in bacteria. It interferes with strand, cutting and resealing function of the inside.

Antibiotics, that interfere with folic acid, metabolism, include sulfonamides and trimethoprim distinct steps. In the pathway leading to folic acid and tetrahydrofolate synthesis

Sulfonamides are structural analogue of para mi, no Benz like acid, which is a substrate for the enzyme dihydrate Arrowhead dentist. Sulfonamides competitively inhibited and does inhibit DNA synthesis.

Trimethoprim inhibits the enzyme dihydrofolate reductase which converts dihydrofolate to tetrahydrofolate. This step is in a later stage in folic acid synthesis.

Eminem synthesis, Inhibitors include Rifampin and rebuilding. Both of these antibiotics inhibit the enzyme bacterial RNA polymerase East.

For more details on indications and adverse effects of antibiotics, please refer to, as you believe. It's Emily online, textbook.

Hope you like today sweetie, I thank you.
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