30 S Protein Synthesis Inhibitors Flashcards
30s
AT
Aminoglycosides
Tetracyclines
50s
Chloramphenicol Erythromycin (Macrolides) Lincosamides (Clindamycin) Linezolid Streptogramins
All bacterial protein synthesis inhibitors are BACTERIOSTATIC EXCEPT
Aminoglycosides
Streptogramins
Chloramphenicol
AMINOGLYCOSIDES
(-) protein synthesis at the 30s ribosomal subunits
SYNERGISTIC w/ beta lactam antibiotics and vancomycin (1+1 = 3)
Neomycin Tobramycin Gentamicin Streptomycin Kanamycin Amikacin
“mycin” - from StreptoMYces
“micin” - from MICrominospora
Most OTOTOXIC aminoglycosides
You will not hear my NAK
NEOMYCIN
KANAMYCIN
AMIKACIN
Most VESTIBULOTOXIC aminoglycosides
Si SG laging naka VEST
STREPTOMYCIN
GENTAMICIN
TOBRAMYCIN
Most NEPHROTOXIC aminoglycosides
NEOMYCIN
TOBRAMYCIN
GENTAMICIN
MOA - Aminoglycosides
bind to the 30s ribosomal subunit and interfere w/ protein synthesis:
- block formation of the initiation complex
- cause misreading of the code on the MRNA template
- (-) translocation
Limited to TOPICAL and ORAL use
Neomycin
Aminoglycosides + B lactam antibiotics - SYNERGISM
if given SEQUENTIALLY
do NOT mix w/ B lactam in same solution
- nucleophilic opening of the B lactam ring
- acylation of the amino group of the aminoglycosides
What is the MOST TOXIC AMINOGLYCOSIDES
TOBRAMYCIN
Aminoglycosides - with ANTAGONISM with other bacteriostatic antibiotics
bacteriostatic + bactericidal = NO NO NO
1+1 = 0
d.t.
(-) of energy dependent uptake of aminoglycosides
interference w/ movement of the ribosome along mRNA
BacterioSTATIC
prevents aminoacyl-tRNA from binding to acceptor site ribosome mRNA complex
TETRACYCLINE
TETRACYCLINES
(+) naphthacene rings
SHORT ACTING
- Tetracycline
- Chlortetracycline
- Oxytetracycline
INTERMEDIATE ACTING
- Demeclocycline
- Methacycline
LONG ACTING
- Doxycline
- Minoxycline
All tetracyclines are excreted renally EXCEPT
Doxycycline - BILE
Absorption of tetracyclines are impaired by foods (antacids, dairy products, divalent cations - Ca, Mg, Fe) EXCEPT
BAWAL D.T.
COMPLEX FORMATION/CHELATION
*tetracycline ring gets attached to divalent cations – locked tetracycline structure – making it UNABSORBABLE
wait for 2-3 hrs bago mag milk or etc
Doxycycline
Minocycline
Aminoglycosides coverage
gram (+) EXCEPT Strep pneumoniae gram (-) Pseudomonas M. tuberculosis - STREPTOMYCIN NO COVERAGE for atypical and anaerobic
Tetracyclines coverage
BROADEST SPECTRUM ANTIBIOTIC
gram (+)
gram (-)
atypical organisms - Legionella, Chlamydophila, Mycoplasma
anaerobic organisms
NO COVERAGE against Pseudomonas
Tetracycline that covers everything but stops at 3PM
Pseudomonas
Proteus
Providencia
Morganella
TIGECYCLINE - pero powerful na to ha
Adverse Effects - Tetracycline
PERMANENT TEETH DISCOLORATION and ENAMEL HYPOPLASIA
bone deformity/growth retardation
AVOID during PREGNANCY and CHILDREN < 8 y/o
GI disturbances
Tetracycline used for SIADH
Demeclocycline
Tetracycline used for CAP and Bronchitis
Doxycycline
Aminoglycosides used for RESISTANT GONORRHEA
Spectinomycin
Aminoglycosides used for visceral leishmaniasis
Paromomycin
