Flashcards in Microbiology and Infectious Diseases Deck (51):
Inhibit bacterial growth by inhibiting protein synthesis
Minimum Inhibitory Concentration
Minimum concentration of antibiotic at which visible growth is inhibited
Give a syndergistic example of 2 types of antibiotics used to treat streptococcal endocarditis
Aminoglycoside and beta lactam
Which types of antibiotics target the bacterial cell wall?
Beta lactams and glycopeptides
What is the name of the major constituent of bacterial cell walls and name the 2 glucose derivatives that it is made up of
N-acetyl muramic acid (NAM)
N-acetyl glycosamine (NAG)
Describe the beta lactam ring
C-C-C-N in a ring structure. Structural analogue of D-alanyl D-alanine
How do beta lactams work?
Interfere with the function of the 'penicillin binding proteins' (transpeptidase enzymes) involved in the peptidoglycan cross linking
Name 4 types of beta lactams
Penicillins, cephalosporins, carbapenems,monobactams
Amoxicillin is an example of what type of antibiotic?
Penicillin- beta lactam
cefuroxime is an example of what type of antibiotic?
meropenem is an example of what type of antibiotic?
azteronam is an example of what type of antibiotic?
Give an example of a glycopeptide
How do glycopeptides work?
Bind directly to terminal D-alanyl-D-alanine on NAM to prevent binding of transpeptidases and thus peptidoglycan cross linking
Glycopeptides work on what sort of bacteria?
Gram +ve- unable to penetrate outer membrane on gram -ves
Name the different antibiotics that act as protein synthesis inhibitors
Macrolides, Lincosamides, streptogramins (MLS)
(others e.g. mupirocin, fusidic acid)
Name an example of an aminoglycoside
How do aminoglycosides work?
Bind to 30s ribosomal subunit
Name an example of a macrolide
How do MLS antibiotics work?
Bind to 50S ribosomal subunit
Name an example of a tetracycline
How do tetracyclines work?
Bind to 30S ribosomal subunit, and interfere with binding of tRNA to rRNA
Name an example of an oxazolidinone
How do oxazolidinones work?
Bind to 50S ribosomal subunit and inhibits assembly of initiation complex.
Name the types of DNA Synthesis inhibitors
Trimethoprim and Sulfonamides
Quinolones and Fluoroquinolones
How do trimethoprim and sulfonamides work?
Inhibit folate synthesis- folic acid is a purine synthesis precursor.
What is the target enzyme in DNA synthesis that trimethoprim targets?
What is the target enzyme in DNA synthesis that sulfonamides target?
Give an example of a trimethoprim/sulfonamide antibiotic
How do quinolones and fluoroquinolones act?
Inhibit enzymes involved in remodelling of DNA during DNA replication
Give an example of a quinolone/fluoroquinolone
What categories of antibiotics act as RNA synthesis inhibitors?
How does rifampicin work?
RNA polymerase inhibitor- prevents synthesis of RNA
What adverse effects are common with aminoglycosides?
reversible renal impairment and ototoxicity -toxic to ear
What adverse effects commonly occur with beta lactams?
Allergic reactions and rashes
What adverse effects commonly occur with linezolid
Bone marrow depression
Safe to use which beta lactams in patients with non-severe penicillin allergy?
Cephalosporins and carbapenems
Safe to use which beta lactam in patients with severe penicillin allergy?
What is the name of the hypervirulent strain of C.Diff?
C.Diff may be precipitated by any antibiotic, but which 4 most commonly?
Co-amoxiclal cephalosporin, ciproflaxin, clindamycin
Clindamycin belongs to what group of antibiotics?
3 strategies of antibiotic use- in order of specificity
Empiric, targeted, susceptibility guided
What antibiotic is used to treat staph A
What antibiotic is used to treat steptococcus pyogenes
What class of antibiotic is used to treat gram -ve bacilli
What type of antibiotic is used to treat anaerobes?
What antibiotic is used to treat gram +ves?
What antibiotic is used as a last option to treat multi-resistant gram negatives?
What antibiotics are used to treat CSF infections?