Antibiotics

Penicillin mode of action

• inhibitor of cell wall synthesis

• inhibits cross-linking

penicillin: true, synthetic, semisynthetic

• true → V&G (Penicillium)

• semisynthetic →ampicillin

penicillin spectrum

• broad → semisynthetic G(+), some G(-)

  • G(-): H. influenzae, Salmonella spp., S. dysenteriae

• narrow →True antibiotic (only G+)

penicillin contains a B-lactam ring, allergies

true

cephalosporin mode of action

• cell wall synthesis inhibitor

• inhibits cross linking

cephalosporin: true, synthetic, semisynthetic

true →Acremonium

penicillin: cidal or static?

cidal

cephalosporin: cidal or static?

cidal

cephalosporin spectrum?

broad: G(+) and some G(-)

cephalosporin is given to most patients w/ penicillin allergies

true

cephalosporin resistant bacteria

• N.gonorrhoea

• Enterobacteriaceae (HAI)

carbapenem mode of action

• inhibitor of cell wall synthesis

• inhibits cross-linking

carbapenem

original →true (Streptomycin cattleya)

all others →semisynthetic

carbapenem: cidal or static?

cidal

carbepenem spectrum

extremely broad →G(+) and G(-), anaerobes

whats the difference between carbapenem and penicillin

• substitution of sulfur atom

• resistant to beta lactamases

Vancomycin mode of action

• inhibitor of cell well synthesis

• Binds to D-ala-D-ala

vancomycin: true, semisynthetic, synthetic

true →Streptomyces orientalis

vancomycin static or cidal

cidal

vancomycin spectrum

narrow →G(+) only

BECCS

• Bacillus

• Enterococcus

• Clostridium

• Streptococcus 

• Staphylococcus

aminoglycosides mode of action

protein synthesis inhibitor (30s causes misreading of mRNA)

aminoglycosides: true synthetic, or semisynthetic

true:

• Streptomycin→Streptomyces spp

• Kanamycin →Streptomyces spp

• Neomycin →Streptomyces spp

• Gentamicin→Micromonospora sp.

aminoglycosides static or cidal

cidal

aminoglycosides spectrum

broad

aminoglycosides notes

toxic and cause renal damage

aminoglycosides: gentamycin G(-)

• gentamycin → aerobic G(-);

  • (PEKS)

  • Proteus

  • Escherichia

  • Klebsiella

  • Serratia

Tetracycline mode of action

• protein synthesis inhibitor

• 30S causes misreading of mRNA

Tetracycline: true, synthetic, or semisynthetic

true →Streptomyces spp

• Oxytetracycline 

• Chlorotetracycline 

Synthetic →doxycyline

Tetracycline: static or cidal

static

Tetracycline spectrum

Broad (atypical: MCR)

• Mycoplasma

• Chlamydia

• Rickettsia

tetracycline side effects

• Chelating calcium → black teeth

• Liver toxicity

• Not given to Pregnant and children

macrolides mode of action

• protein synthesis inhibitor

• binds to 23s rRNA of large 50s inhibiting chain elongation

macrolide: true, semisynthetic, or synthetic

• True → erythromycin (Saccharopolyspora)

• Semisynthetic →azithromycin

macrolide static or cidal?

static

macrolide spectrum

Broad: G(+) aerobic and anaerobic, mycoplasmas sp.

macrolides are used for penicillin and cephalosporin allergies

true

azithromycin is commonly perscribed for Chlamydia

true; Z-pack

what is macrolides usually prescribed with?

amoxicillin

lincosamide mode of action

protein synthesis inhibitor; 50s inhibits peptidyl transferase activity

lincosamides true, synthetic, or semisynthetic

true →Streptomyces sp.

semisynthetic →clindamycin

lincosamides static or cidal

static

lincosamide spectrum

broad: G(+) some G(-) (beta lactamase producers)

clindamycin can treat what?

CA-MRSA

lincosamides can support the growth of what?

C. diff

chloramphenicol mode of action

protein synthesis inhibitor ; 50s inhibits peptidyl transferase activity

chloramphenicol, true, synthetic, or semisynthetic

true →Streptomyces venezuelae

chloramphenicol static or cidal?

static

chloramphenicol spectrum

broad G(+), G(-), anaerobes, rickettsiae

side effects of chloramphenicol

• aplastic anemia

• leukemia

• neurotoxin rxns

• inhibits mitochondrial protein synthesis

• “grey baby syndrome”

oxazolidinones mode of action

protein synthesis inhibitor (binds to 23s rRNA to prevent 70s subunit)

oxazolidinones; true, semi-synthetic, synthetic

synthetic →Linezoid

oxazolidinones static or cidal?

static/cidal

oxazolidinones spectrum

broad: G(+) anaerobes, MRSA, VRE, penicillin resistant S.pneumonia

oxazolidinones side effects

few side effects, only used in hospitals

sulfonamides mode of action

metabolic antagonist (inhibits folic acid production; purines)

sulfonamides: true, synthetic, or semisynthetic

synthetic

sulfonamides static or cidal

static

sulfonamides spectrum

broad

sulfonamides has an analogy of what?

PABA

what enzyme do sulfonamides inhibit to prevent folic acid production

dihydropteroate synthase

trimethoprim mode of action

metabolic antagonist; Inhibits enzyme dihydrofolate

reductase

trimethoprim: true, synthetic, or semisynthetic

synthetic

trimethoprim static or cidal

• static

• cidal = synergism

trimethoprim spectrum

broad

trimethoprim is synergistic or antagonistic?

synergistic with other sulfa drugs; bactrium

trimethoprim side effects

photosensitivity and abdominal pain

fluoroquinolones mode of action

Nucleic acid synthesis inhibition; Inhibits topoisomerase IV (type II) & DNA-gyrase

fluoroquinolones; true, synthetic, or semi-synthetic

synthetic

fluoroquinolones examples

• norfloxacin

• ciprofloxacin

fluoroquinolones cidal or static?

cidal

fluoroquinolone spectrum

broad

fluoroquinolones side effects

tendonitis and tendon ruptures

what are fluoroquinolones highly effective against?

enteric bacteria

Rifamycin mode of action

Nucleic acid synthesis inhibition; Inhibits RNA polymerase (beta subunit)

Rifamycin: true, semi-synthetic, synthetic?

semi-synthetic

Rifamycin spectrum

broad:

• Rifampin →Mycobacterium infection

• Prophylaxis → bacterial meningitis exposure

Rifamycin causes what side effects?

red sweat and urine

rifamycin can be used as a multidrug for what?

TB and mycobacterial infections

Rifamycin can be used against?

Haemophilus influenzae, and type B meningitis

Tamiflu: anti-what?

anti-viral

tamiflu associated disease

influenza

tamiflu mode of action

neuramidase inhibitor

tamiflu is a cure for influenza

false

tamiflu resistance is seen

true

Xofluza: anti what?

anti-viral

xofluza associated disease

influenza

xofluza mode of action

inhibits transcription: prevents cap snatching = hosts 5’ cap are added to viral transcription

xofluza resistance is seen

true

Acyclovir and Vidarabine: anti-what?

anti-viral

Acyclovir & Vidarabine associated disease

Herpesviridae

Acyclovir & Vidarabine: mode of action

• Inhibit replication (chain termination of DNA replication)

• TK (herpesvirus-specific thymidine kinase) to phosphorylate nucleosides into nucleotides

Acyclovir & Vidarabine are analogs that inhibit what?

replication

Acyclovir & Vidarabine treat what?

• Herpes 

• Chickenpox 

• Shingles

• Cytomegalovirus 

HAART: antiwhat?

anti-viral

HAART associated disease

HIV

HAART mode of action

Combination drug therapy targeting multiple HIV life-cycle stages

what anti-viral is a drug cocktail used to curtail resistance

HAART

classes of antivirals

• NRTIs

• NNRTIs

• Protease inhibitors

• Integrase inhibitors

• Fusion inhibitors

PrEP anti-what?

anti-viral

PrEP associated disease

HIV