Toxins Flashcards
What are the functions of toxins?
Target specific cells in an organism, punching holes in their membranes, or modifying intracellular components
What is toxigenesis?
The ability to produce toxins
What are endotoxins?
Structural components of bacteria
Where are endotoxins located?
On the cell envelope, on the outside surface of bacteria
What are lipopolysaccharides?
Large molecules that are a vital component of the outer membrane of Gram-negative bacteria
What recognises forign molecules and alerts the immune system?
Patternn recognition receptors
What are exotoxins?
Usually proteins secreted by bacteria and stimulate host responses
Are toxins major contributors to disease?
Yes
What do enterotoxin, neurotoxin and hemolysin describe?
The targets of bacterial exotoxins
What are some common activities for exotoxins?
Degrading host membranes and forming pores in host membranes
What are the two subunits of toxins?
A and B
What is the subunit A?
Active
Has the toxic activity
What is the subunit B?
Binding
Binds to host cells
Does the A subunit act before subunit B?
Yes, the A part is delivered to the host cell through interactions between host cell and the B part
Where is AB toxin secreted from?
Bacterial cell
Where does B toxin bind to?
A specific receptor of host cell
Where is A toxin transferred?
Across host membrane into the host cell
What is A toxin able to do once in the host cell?
Interfere with normal cell function
What is diphtheria?
Thick coating at the back of the throat
What can diphtheria lead to?
Difficulty breathing
Paralysis
Death
What does diphtheria toxin cause?
A block of protein synthesis in the host
How much of diphtheria toxin is enough to kill a cell?
A single molecule
What is the mortality rate of diphtheria in the young?
High
Why is diphtheria morality in the young high?
The destruction of tissues in vital organs due to the blockage of protein synthesis
