Week12C1 : pathogens Flashcards
the endotoxins are heat ____ while the exotoxins are heat ____
endotoxin are heat stable while exotoxins are heat labile
is there any antibodies relesed for LPS?
no
** T or F : the LPS is a very effective activator of the immune system
true
the gram___ bacteria effectively activate the immune system
- (because of the endotoxin lipidA)
**what is the name of the form of innactivated toxin used in vaccines
toxoid
is there a vaccine against endotoxin?
no because can’t be innactivated by formaldehyde or heat.
___ toxin produces fever
endotoxin
gram - are all ___toxin
endotoxin
what are pathogenicity islands?
specific region of the chromosome that encode for virulence factors
name the virulence factors seen in class
- adhesiin
- capsule
- invasins
- type 3 and type 4 secretion system
what are the two basic features of virulence
- invasivness
2. toxigenicity
define invasiness
capacity of a microorganisms to become establish in the host system
define toxigenicity
capacity of a microorganism to produce toxins
**which one is more specific, invasive microorganisms or toxic microorganisms
toxic.
where does the afimbiral adhesin attaches
to the glyco and lipo proteins of the cells (close attachment)
where does the fimbiral adhesin attaches
attachement to the polymrs of the fimbria or pili (loose attachement)
what are the two pathogens that uses the capsule method for the invasion of tissues
the streptococcus pneumonia and the haemophilus influenza and e.coli
** the capsule is only a virulence factor
not always, used by many non-pathogenic bacteria
name this enzyme: degrade hyaluronic acid
hyaluronidase
what are the pathogene that uses hyaluronidase to invade cells
- streptococci
- staphylococci
- clostridia
name this enzyme: degrades the protein collagen present in connective tissues. what pathogen uses this enzyme
collagenase, clostridium
degrades lecithin (phosphatidylcholine) in cell membrane and causes lysis of the RBC and destroys tissues.
lechinase
name a pathhogen that uses lecithinase
clostridium
what is the action of this enzyme: hemolysin
causes the lysis of red blood cells
name the enzymes seen in class that are in the category of hemolysin
lecithinase, phospholipase
what are the different method of invasiveness
adhesin capsules invasins enzyme that destroy tissues type 3 secretion system and type 4
what is the action of this enzyme: leucocidin
causes lysis of the leucocytes.
what are the pathogens that uses leucocidin
staphylococci, streptococci and gram negative
what is the action of this enzyme: coagulase
causes the fibrin to be deposited on bacterial cells and cloaks the bacteria from the immune system
what pathogens uses coagulase
staphylococci
what are the pathogens that use invasins
mycobacterium, salmonella, listeria and chlamydia
the gram ____ uses the T3SS and T4SS
negative
name the steps in the T3SS invasion
- invasion
- blocking of the phagosome maturation
- take controle of host cell
in the case of diphteria, the site a of the AB toxin will interfere with the ____
ADP-ribosyltransferase
what is the effect of the a subunit in the AB5 toxin of the vibrio cholarea
activation of adenylate cyclase (increase of CAMP) and so no Na+ can enter and Cl- and HCO3- are released from the cell.
the gram ___ contain lipid A, an endotoxin
negative
T or F : the endotoxins are very effective activators of the immune system
true
