micro details Flashcards
what virulence factor allows E coli to cause neonatal meningitis?
K-capsule (usually K-1)– inhibs complement, phagocytosis and other host response. (the capsule = immunogenic and Abs = protective)
why are B-cells not very effective agst TB?
facultative IC org–mainly reside w/in Macrophages
major toxin of C. Diptheria works by…
inactivates EF-2 via ribosylation, thus inhibiting host-cell prot synth
major tox in of C. Diptheria = closest to what other toxin?
Pseudomonas aeruginosa exotoxin A- inactivates EF-2 via ribosylation, thus inhib host-cell prot synth
How does the Pertussis toxin work?
Disinhibits adenylate cyclase via Gi ADP ribosylation, increasing cAMP production in host cell; causes increased histamine sensitivity and phagocyte dysfunc
How does Cholera toxin work?
Activates adenylate cyclase via Gs ADP ribosylation, increasing cAMP production in the host cell; causes secretory diarrhea, dehydration & electrolyte deposition
which toxin increases cAMP by Gi ADP ribosylation?
Pertussis
which toxin increases cAMP by Gs ADP ribosylation?
Cholera
which toxins are AB toxins where the B subunit induces receptor mediated endocytosis/internalization of a toxin by enterocytes and the A subunit catalyses the removal of an Adenosine residue, which prevents binding of tRNA to the 60S ribosomal subunit/inhib prot synth?
Shigella toxin and shiga-like-toxin (E. Coli)
Name 6 common illnesses caused by lysogenic phages
- HUS (shiga-like-toxin)
- TTP (shiga-like toxin)
- Botulism
- cholera
- diptheria
- Toxic shock-like sysdrome (S. pyogenes)
which bact. = assoc. w/fever, abdo pain, diarrhea and faintly erythematous macules on abdo called “rose spots”
salmonella typhi - typhoid fever
What are the virulence factors acquired by specialized transduction?
REMEMBER– “specialized transduction = lysogenic phage!”
- COBEDS
1) Cholera
2) O-toxin from salmonella
3) Botulism
4) Exotoxins (STLS from Strep pyog)
5) Diptheria
6) Shiga-like-toxin (causes HUS and TTP)
Name 6 common illnesses caused by lysogenic phages
- HUS (shiga-like-toxin)
- TTP (shiga-like toxin)
- Botulism
- cholera
- diptheria
- Toxic shock-like sysdrome (S. pyogenes)
what is specialized transduction?
DNA being introduced from lysogenic phages (they integrate into DNA, and when they leave, they accidentally take some of the original bacteria with them. When they move on to the next bacteria, they infect that bacteria with the old host bacteria).
What are the virulence factors acquired by specialized transduction?
REMEMBER– “specialized transduction = lysogenic phage!”
- COBEDS
1) Cholera
2) O-toxin from salmonella
3) Botulism
4) Exotoxins (STLS from Strep pyog)
5) Diptheria
6) Shiga-like-toxin (causes HUS and TTP)
LPS is also called…
endotoxin
what is the toxic part of LPS?
lipid A
name 3 bacterial toxins that interfere w/ protein synthesis:
- Diptheria Corneybacterium
- Pseudomonas exotox
- Shigella (shigella-like)
many exotoxins are AB toxins where the A portion ______ and the B portion _____
A: active portion of toxin
B: Binds to cell receptor
name 4 bacterial toxins that result in increased cAMP (associated w/fluid moving into another space)
I like cAMPing BC it’s ChEAP
- B. Cerius (heat labile enterotox- activate adenylate cyclase)
- C. Jejuni (enterotox- activate adenylate cyclase)
- CHolera (cholera tox- ADP ribosylation activates Gs- activates adenylate cyclase)
- . ETEC (heat labile toxin, activates Gs)
- Anthrax (edema factor- intrinsic adenylate cyclase activity in toxin)
- Pertussis (ADP ribos. INACTIVATES Gi)
name 3 bacterial toxins that interfere w/ protein synthesis:
- Diptheria
- Shigella (shigella-like)
- Pseudomonas exotox
Haemophilus grows on…
chocolate Agar- w/factors 5 and 10
what grows on Thayer Martin media?
Gonorrhea– you have too many martinis, you can get gonorrhea
pertussis grows on…
Bordet-genou (a potato medium!)
BORDETella Pertussis
Diptheria grows on
Tellurite
What grows on MacConkey agars?
lactose-fermenting GN
contains bile salts that prevent GP from growing
What grows on Charcoal yeast extract w/cysteine?
Legionella
Legionella grows on…
Charcoal yeast extract w/cysteine
Fungi grows on…
Sabaraud agar
4 antibact that inhib cell wall…
- Penicillins
2 Cephalosporins - Vancomycin
- Carbapenims
which has an outer membrane, GN or GP?
GN
which has LPS, GN or GP?
GN
which has thick peptidoglycan layer, GP or GN?
GP
which stains pink, GP or GN? and which stains purple?
pink = GN purple = GP
which has cytoplasmic membrane, GP or GN?
both!
which has teichoic acid, , GP or GN?
GP– used for attachment
which stains pink, GP or GN? and which stains purple?
pink = GN purple = GP
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires a phage?
transduction
which genetic mechanism(s) requires homologous recombination?
Hfr
Transduction
Transformation
(all forms where new DNA = being incorp into chromosomal DNA)
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires naked DNA
transformation
which bacteria are transformation competent?
SHiN bacteria
S. pneumo
HiB
Neisseria
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires oriT + tra for transfer of genetic material?
conjugation (plasmid w/transposon on board)
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires oriT for transfer of genetic material?
Hfr and conjugation
what is oriT?
Origin of Transfer:
short DNA seq. necessary for transfer of a bacterial plasmid/chromosomal DNA from a bacterial host to recipient during bacterial conjugation. (The oriT is cis-acting - it is found on the same plasmid that is being transferred, and is transferred along with the plasmid. The origin of transfer consists of three functionally defined domains: a nicking domain, a transfer domain, and a termination domain.)
which genetic mechanism(s) (Hfr, Transduction, Conjugation, Transformation) requires oriT + tra for transfer of genetic material?
conjugation (plasmid w/transposon on board)
majority of multi-drug resistant orgs arise from what genetic mech?
conjugation
3 bact causes of typical pneumonias (gen represented as older, really sick people w/lobar pneumonia)
- strep pneumo
- HiB
- S. aureus
txt diptheria w/
penicillin (or erythromycin if penicillin allergy) + antitoxin
two unique things about mycoplasma pneumoniae and Ureaplasma
- no cell wall!
2. uses sterols in cell membrane
super sick kid, not vaccinated (immigrant/vac. status unknown), bull neck (LAD), psudomembrane
Diptheria!
corney bacterium diptheria
txt diptheria w/
penicillin, antitoxin + vaccine
how do you txt strep throat from S. pyogenes?
penicillin
how does sinusitis present?
after viral ifxn, sinus pain, head congestion, frontal tenderness/maxillary tenderness
otitis externa- ear pain = assoc. w/what 2 bugs?
- Pseudomonas aeruginosa– from SWIMMING IN INFECTED WATER
- S. aureus
P.S. my ear hurts!!!
how can you tell if sinusitis = caused by anaerobe?
smelly bc they make H2S
how does sinusitis present?
after viral ifxn, sinus pain, head congestion, frontal tenderness/maxillary tenderness
otitis externa- ear pain = assoc. w/what 2 bugs?
Pseudomonas aeruginosa– from SWIMMING IN INFECTED WATER
S. aureus
P.S. my ear hurts!!!
Pseudomonas causes what two things from being in water too long?
Otitis externa
Hot tub folliculitis
diarhea from shigella is ALWAYS…
BLOODY!! (bacillary dysentery)
- SHit i’m BLEEDING from SHigella
what is the most common bacterial diarrhea, and it comes from spoiled chicken?
C. jejuni
salmonella is associated w/which foods?
chicken and egg products
diarhea from shigella is ALWAYS…
BLOODY!! (bacillary dysentery)
- SHit i’m BLEEDING from SHigella
B. cereus = assoc w/
reheating rice (chinese food, etc)
C. perfringens = assoc w/what food
reheated meat
vibrio cholerae = assoc. w/what food?
seafood
what is assoc w/ honey in babies?
C. botulinum —> neurotoxin, can’t release ACh
ifxn w/EHEC commonly causes what 2 extraGI things?
HUS
TTP
(O157:H7 Shiga-like toxin)
0157:H7
EHEC- shiga-like toxin
undercooked hamburgers = commonly assoc w/
EHEC
ifxn w/EHEC commonly causes what 2 extraGI things?
HUS
TTP
(O157:H7 Shiga-like toxin)