Micro Flashcards
Herpesviruses
Enveloped (from nuc membrane), dsDNA, linear HSV-1, 2, VZV, EBV, CMV, HHV-6/7: roseola (exanthem subitum), HHV-8 (kaposi sarcoma)
Hepadnavirus
Enveloped, partially DS and circular
HBV
Hepadnavirus (enveloped, circular DNA)
Adenovirus
Naked, linear dsDNA Febrile pharyngitis, acute hemorrhagic cystitis, pneumonia, conjunctivitis
Parvovirus
naked, ssDNA (-) B19, Aplastic crises, slapped cheeks: erythema infectiosum (fifth dz)
Papillomavirus
Naked, circular dsDNA HPV
Polyomavirus
Naked circular dsDNA JC virus: PML in HIV BK virus: transplants, kidney
Poxvirus
Enveloped, dsDNA, linear (largest DNA virus) Smallpox, cowpox, molluscum contagiosum
Positive stranded RNA viruses:
Retro Toga Flavi Corona Hepe Calici Picorna
Nonenveloped RNA:
Calici, Picorna, Reo (dsRNA), Hepe
Rotavirus
Reovirus, linear dsRNA, naked, icosahedral, 10-12 segments
Picornavirus
Poliovirus Echovirus - aseptic meningitis Rhinovirus Coxsackievirus - aseptic meningitis, herpangina, HFMD, myocarditis, pericarditis HAV PERCH on a pic
Hepatitis E
Hepevirus linear +ssRNA, naked, icosahedral
Norovirus
Calicivirus Naked, +ssRNA, linear, icosahedral
Flaviviruses:
Enveloped, +ssRNA, linear, icosahedral HCV Yellow fever Dengue St. Louis encephalitis West Nile Virus
Togaviruses:
enveloped, +ssRNA, linear, Icosahedral Rubella Eastern/Western equine encephalitis
Retroviruses
enveloped, +ssRNA, linear, have RT HTLV: icosahedral, T-cell leukemia HIV: complex, conical
Coronaviruses
enveloped, +ssRNA, linear, helical SARS, common cold
Influenza
Orthomyxo, -ssRNA, linear, 8 segments, helical
Paramyxoviruses
Enveloped, -ssRNA, linear, helical All contain surface F protein, causes resp epithel cells to fuse and form multinuc cells Parainfluenza - croup RSV - bronchiolitis tx: ribavirin, pneumonia - palivizumab is MAb against F protein, prevents in preme Measles, Mumps
Rhabdoviruses
enveloped, -ssRNA, linear, helical
Filoviruses
enveloped, -ssRNA, linear, helical Ebola/Marburg hemorrhagic fever, often fatal
Arenaviruses
enveloped, -ssRNA, circular, 2 segments, helical LCMV
Bunyaviruses
enveloped, -ssRNA, circular, 3 segments, helical California encephalitis, hantavirus
HDV
Deltavirus Enveloped, -ssRNA, circular, requires HBV coinfection
Negative stranded RNA viruses:
FAB PRO Filo, arena, bunya, paramyxo, rhabdo, orthomyxo Must transcribe - to +, brings its own RNA-dep RNA polymerase
Segmented viruses:
BOAR RNA viruses, Bunya, Orthomyxo, Arena, Reo
Rubella
Togavirus, Naked, linear +ssRNA High fever, post. auricular LA, fine rash starts on face, spread centrifugally TORCHES infection: blueberry muffin baby b/c extramedullary hematopoiesis
Roseola:
HHV-6, sometimes 7 High fevers, can cause seizures, followed by diffuse macular rash, starts on trunk, spreads peripherally
Left off at Measles pg 164
sgadfg
Which bugs make a toxin that ADP-ribosylate EF-2?
Diptheria (DT) and Pseudomonas (Exotoxin A)
Both AB toxins, block protein synth (G+ & G-)
Which bugs make toxin that overactivates adenylate cyclase?
ETEC - heat LABILE toxin Cholera - permanently activates Gs
Pertussis: ADP ribosylates Gi, disables it - impairs phagocytosis Increase cAMP, causing Cl- secretion and H2O efflux in gut.
All AB toxins
How do Shiga and Shiga-like toxin function?
Inactivate 60S ribosome by removing adenine from rRNA Both AB toxins, block protein synthesis
ST –> GI mucosal damage –> dysentery
ST and SLT both enhance cytokine release, –> HUS
EHEC does NOT invade host cells
Which bug has a PRP capsule?
Hib
Picorna Viruses: charact/imp ones
ss + linear naked RNA, PERCH on a Pic Polio Echo (aseptic meningitis) Rhinovirus Coxsackie (aseptic meningitis, herpangina, HFMD, myocarditis, pericarditis) HAV
Catalase positive orgs:
PLACESS for cats
Pseudomonas, Listeria, Aspergillus, Candida, E. coli, S. aureus, Serratia
Encapsulated orgs:
SHiNE SKiS
Strep pneumoniae, H influenzae B, Neisseria meningitidis, E. coli, Salmonella, Klebsiella pneumoniae, group B Strep
Spirochetes
BLT Borrelia (big), Leptospira, Treponema
B anthracis toxin:
Trimeric exotoxin containing:
Protective antigen - translocates both toxins into the cell, necessary for funtion
Edema factor - mimics adenylate cyclase to increase cAMP and increase fluid secretion –> edematous borders of black eschar
Lethal Factor - zinc-dependent protease, inhibits MAPK signaling –> apoptosis and multisystem physiologic disruption
Which bacterium has a polypeptide capsule (D-glutamate)?
B. anthracis G+ spore forming rod
Pertussis toxin
Pertussis toxin: ADP-ribosylates Gi, which increases cAMP –> edema and impairs phagocytosis
C. dif toxins
Toxin A: enterotoxin, binds brush border of gut. Recruits and activates neutrophils –> cytokine release that causes mucosal inflamm, fluid loss, diarrhea
Toxin B: cytotoxin, induces actin depolymerization –> mucosal cell death, bowel wall necrosis, and pseudomembrane formation
PCR detection of toxin genes for diagnosis!
Genes for bacterial toxins in lysogenic phage:
SLT
Botox
Cholera
Diptheria toxin
Erythrogenic toxin of GAS
(BCDES)
Legionella pneumophila
G- rod, stains poorly use silver stain
Charcoal yeast extract with iron and cysteine
detect Ag via urine EIA
Legionanaires disease: severe pneumonia, fever w/ relative bradycardia, GI - watery diarrhea, CNS sx, hyponatremia
Leptospira interrogans
spirochete, in water contaminated with animal urine
Leptospirosis: flu-like sx, jaundice, photophobia w/ conjunctival suffusion (erythema w/o exudate)
See among surfurs and in tropics
Severe form: Weil Disease: icterohemorrhagic leptospirosis - jaundice, azotemia (liver/kidney dysfx), fever, hemorrhage, anemia