M4A1 Antibacterial Antibiotics Lecture Review

A set of 90 vocabulary-style flashcards covering the historical background, classification, source, structure-activity relationship (SAR), mechanism of action, and adverse effects of antibacterial antibiotics based on lecture notes.

Pasteur and Joubert

In $1877$, they observed that anthrax bacilli were killed when grown in culture with certain bacteria.

Alexander Fleming

In $1929$, he identified the bacterial properties of Penicillin.

Florey and Chain

In $1938$, they led the practical medical exploitation of Penicillin.

Vuillemin

The individual who defined "antibiosis" as meaning "against life."

Waksman

In $1942$, defined an antibiotic as a substance produced by microorganisms with the capacity to inhibit or destroy other microorganisms.

Metabolism

The biological process of which an antibiotic is a naturally occurring product.

Low Concentrations

The high-potency requirement for a substance to be classified as an antibiotic.

Bacitracin

An antibiotic that targets the cell wall to interrupt mucopeptide synthesis, exhibiting bactericidal activity.

Cephalosporin (Cell Wall)

An antibiotic that interrupts cell wall cross-linking and is bactericidal.

Cycloserine

An antibiotic that acts on the cell wall by interrupting the synthesis of cell wall peptides.

Penicillins (Process)

Antibiotics that act as bactericidal agents by interrupting cell wall cross-linking.

Vancomycin (Process)

A bactericidal antibiotic that interrupts mucopeptide synthesis.

Amphotericin B

An agent that targets the cell membrane to interrupt membrane function, categorized as fungicidal.

Nystatin

A fungicidal antibiotic that targets membrane function.

Polymyxins

Bactericidal antibiotics that target cell membrane integrity.

Chloramphenicol (Subunit)

An antibiotic that binds to the $50S$ ribosomal subunit to inhibit protein synthesis.

Erythromycin (Subunit)

A bacteriostatic antibiotic that binds to the $50S$ ribosomal subunit.

Lincomycins (Subunit)

Antibiotics that inhibit protein synthesis by targeting the $50S$ ribosomal subunit.

Aminoglycosides (Site)

Bactericidal antibiotics that target the $30S$ ribosomal subunit, affecting protein synthesis and fidelity.

Tetracyclines (Site)

Bacteriostatic antibiotics that target the $30S$ ribosomal subunit to inhibit protein synthesis.

Actinomycin

A pancidal agent that targets nucleic acids to interrupt $DNA$ and/or $RNA$ synthesis.

Griseofulvin

A fungistatic agent that interrupts cell division and microtubule assembly.

Mitomycin C

A pancidal agent that targets nucleic acids to interrupt $DNA$ synthesis.

Rifampin

A bactericidal agent that targets nucleic acids to interrupt $mRNA$ synthesis.

Streptomyces lincolensis

The microbial source of the antibiotic Lincomycin.

Penicillium notatum

The natural source used to derive Penicillin.

Penicillium chrysogenum

The source used for producing Penicillinase-Resistant Penicillin.

Cephalosporium acremonium

The microbial source of the antibiotic Cephalosphorin.

Bacillus Subtillis

The microbial source of the antibiotic Bacitracin.

Streptomyces orchidaceus

One of the microbial sources for the antibiotic Cycloserine.

Streptomyces orientalis

The microbial source of the antibiotic Vancomycin.

Streptomyces venezulae

The microbial source of the antibiotic Chloramphenicol.

Streptomyces griseus

The microbial source of the antibiotic Streptomycin.

Micromonaspora purpurea

The microbial source of the aminoglycoside Gentamicin.

Streptomyces fradiae

The microbial source of the antibiotic Neomycin.

Streptomyces aureofaciens

The microbial source of the antibiotic Chlortetracycline.

Streptomyces rimosus

The microbial source of the antibiotic Oxytetracycline.

Streptomyces erythreus

The microbial source of the antibiotic Erythromycin.

Bacillus colistinus

The microbial source of Colistin, also known as Polymyxin $E$.

Bacillus polymyxa

The microbial source of the antibiotic Polymyxin.

Streptomyces mediterranei

The microbial source of Rifampin (Rifampicin).

Streptomyces natalensis

The microbial source of the antibiotic Natamycin.

Streptomyces capreolin

The microbial source of the antibiotic Capreomyxin.

Streptomyces nodosus

The microbial source of the antifungal Amphotericin $B$.

Streptomyces noursei

The microbial source of the antifungal Nystatin.

Penicillium griseofulvum

The microbial source of the antibiotic Griseofulvin.

Beta-Lactam Mechanism

The inhibition of dipeptidoglycan biosynthesis by acylating bacterial $D$-transpeptidase.

D-transpeptidase

The specific enzyme acylated by beta-lactam antibiotics to prevent peptide cross-linking.

PBPs 1a and 1b

Penicillin-binding proteins associated with cell elongation; inhibition leads to spheroplast formation and rapid lysis.

PBP 2

Penicillin-binding proteins involved in maintaining the rod shape of bacilli.

PBP 3

Penicillin-binding proteins essential for septum formation during cell division.

PBP 4, 5, 6

Carboxypeptidases responsible for the hydrolysis of $D$-alanine–$D$-alanine terminal peptide bonds.

Bacterial Resistance mechanisms

Includes bacterial enzyme elaboration, decreased permeability, porin alteration, and changed PBP affinity.

Beta Lactam Ring

The active component essential for penicillin SAR.

Thiazolidine Ring

A five-membered sulfur-containing ring required for the structure of penicillin.

Carboxylic Acid (SAR)

A functional group in penicillins that is essential for solubility.

Acylamino Side Chain

The modification site on penicillins that determines the spectrum of antibacterial activity.

Penam

The core bicyclic ring system found in penicillin structures.

Penicilloic Acid

The inactive product formed when the beta-lactam ring of penicillin is hydrolyzed.

Penicillin G

Benzyl Penicillin; an acid-labile antibiotic often administered in repository forms like Benzathine or Procaine.

Penicillin V

Phenoxymethyl Penicillin; an acid-stable natural penicillin suitable for oral administration ($PO$).

Methicillin

The prototype penicillinase-resistant drug, chemically known as $2,6$-dimethoxyphenylpenicillin.

Nafcillin

A lipophilic penicillinase-resistant drug with naphthalene rings; primarily eliminated via biliary excretion.

Isoxazolyl Penicillins

A group including Oxacillin and Cloxacillin where the isoxazolyl ring prevents binding to $\beta$-lactamases.

Ampicillin

An aminopenicillin ($α$-aminobenzylpenicillin) that is poorly absorbed from the GIT and given $IV$.

Amoxicillin

$\text{D}$-$α$-Amino-$p$-hydroxybenzylpenicillin; an aminopenicillin that is well-absorbed orally.

Carbenicillin

The prototype carboxypenicillin ($α$-carboxybenzylpenicillin) used for $UTI$ caused by $P. aeruginosa$.

Ticarcillin

An isostere of carbenicillin where the phenyl group is replaced by a thienyl group.

Piperacillin

The most potent and useful extended-spectrum acylureidopenicillin, though it is acid-labile.

Mezlocillin

An acylureidopenicillin recommended specifically for serious bacterial infections.

Penicilloyl Proteins

The antigenic components that act as the most frequent allergens in penicillin hypersensitivity.

Class I Inhibitors

$\beta$-lactamase inhibitors that act as suicide substrates to prevent the degradation of $\beta$-lactams.

Augmentin

A combination drug consisting of Clavulanic Acid and Amoxicillin.

Unasyn

A combination drug consisting of Sulbactam and Ampicillin.

Tazocin

A combination drug consisting of Tazobactam and Piperacillin.

Timentin

A combination drug consisting of Ticarcillin and Clavulanic Acid.

Clavulanic Acid

A $\beta$-lactamase inhibitor isolated from Streptomyces clavuligeris.

Class 2 Inhibitors

Agents that possess potent antibacterial activity while also causing transient inhibition of $\beta$-lactamases.

DHP-1

Renal dehydropeptidases-1; the enzyme responsible for inactivating carbapenems in the kidney.

Thienamycin

A carbapenem isolated from Streptomyces cattleya.

Aztreonam

A monobactam with high affinity to $PBP 3$; active against aerobic $G(-)$ but inactive against $G(+)$.

Tigemonam

A newer monobactam noted for its excellent oral activity.

Cephalosporin SAR (Ring)

Requires a Dihydrothiazine ring fused to the beta-lactam.

Acetoxylmethyl

Identified as the most reactive site in the cephalosporin structure.

Klebsiella

A bacterial genus against which cephalosporins exhibit uniquely potent activity.

MTT Side Chain

$N$-methyl-$5$-thiotetrazole; associated with hypoprothrombinemia and disulfiram-like effects in certain cephalosporins.

Ring I (Aminoglycosides)

The part of aminoglycoside structure essential for broad-spectrum activity and the primary target for inactivating enzymes.

Streptomycin use

Clinically used for tularemia, bacterial endocarditis, and tuberculosis ($TB$).

Neomycin use

Used for preoperative bowel sanitation and treating enteropathogenic $E. coli$ infections.

Octahydronapthacene

The core structure of tetracyclines, consisting of four annulated $6$-membered rings.

Tetracyclines (Chelation)

The most important feature of this class, allowing them to form stable salts with metal ions.

Minocycline ADR

A potent tetracycline known for the adverse effect of vestibular toxicity.

Doxycycline prophylaxis

The safest tetracycline for renal impairment and the agent of choice for traveler's diarrhea prophylaxis.

Disulfiram-like effect

An adverse reaction occurring when cephalosporins containing the $MTT$ group are taken with $CNS$ drugs.

6-methyl ester of erythromycin

The chemical description of the macrolide Clarithromycin.

Lincomycen Binding

Inhibits protein synthesis by binding specifically to the $50S$ ribosomal subunit.

Red Man Syndrome

An adverse reaction (flushing) associated with the rapid $IV$ administration of Vancomycin.

Polymyxin B

A polypeptide antibiotic derived from $B. polymyxa$ used for systemic $UTI$ and septicemia.

Gray Baby Syndrome

A toxic syndrome in neonates caused by the antibiotic Chloramphenicol.

Tigecycline

The first antibiotic in the glycylcycline class, structurally related to minocycline with $5\times$ the ribosomal affinity.