11. Antibiotic Production I-> Discovery and Mechanism of Action

Antibiotic

Any compound that inhibits the growth or actively kills microorganisms, usually referring to compounds that selectively target bacteria.

Bacteriostatic

Antibiotics that inhibit bacterial growth without actively killing.

Bactericidal

Antibiotics that actively kill bacteria.

Broad-spectrum antibiotic

Antibiotics that are active against a wide range of pathogenic bacteria.

Narrow-spectrum antibiotic

Antibiotics that are active against a specific family or limited number of pathogenic bacteria.

Minimum inhibitory concentration (MIC)

The lowest concentration of a drug that will inhibit the visible growth of an organism after overnight incubation.

Actinomycetes

Gram-positive, non-motile bacteria often found in the soil that produce antibiotics and other important compounds.

Traditional approach to antibiotic discovery

Screening environmental samples, identifying antibiotic-producing organisms, fermentation, and purification to isolate pure antibiotics.

Industrial production of antibiotics

Improving productivity, selection and maintenance of stable producers, mutagenesis and selection of overproducers, fermentation medium optimization, and fermentation process optimization and scale-up.

Beta-lactams

Penicillins and cephalosporins, which target the peptidoglycan in the bacterial cell wall.

Aminoglycosides, macrolides, glycopeptides, polymyxins, tetracyclines, and ansamycins

Important classes of natural product antibiotics.

Oxazolidinones, (fluoro)quinolones, azoles, and sulfonamides

Important classes of synthetic antibiotics.

Antibacterial targets

Processes essential for bacterial survival, including cell wall biosynthesis, protein synthesis, and nucleic acid synthesis.

β-lactam antibiotics

The most widely used class of antibiotics that target the peptidoglycan in the bacterial cell wall.

Penicillin binding protein (PBP)

A transpeptidase that catalyzes peptidoglycan cross-linking and is the target of β-lactam antibiotics.

Antimicrobial resistance (AMR)

The ability of bacteria to resist the effects of antibiotics.

Carbapenase

An enzyme that degrades carbapenems, a class of β-lactam antibiotics.

Enterobacteriaceae

A family of Gram-negative bacteria that includes many widespread pathogens.

Antibacterial resistance mechanisms

Destruction, exclusion, and target modification.

Adaptive evolution

The development of resistance through random mutagenesis and horizontal gene transfer.