Toxins Flashcards
Define: Toxins
Specific, characterisable poisonous chemicals
Toxins can be produced by…
Microbes (including fungi)
Animals
Plants
What are plant toxins?
Toxic compounds that are normal components of plants. The components normally serve defence functions against insects, herbivorous animals, bacteria and fungi
Name some examples of plant toxins
Digitalin
Pyrrolzidine alkaloids
Grayanotoxin
Phytohaemagglutinin
What are the effects of phytohaemaglutenin
- Induces cell mitosis
- Affects host cell transport systems
- Agglutinates red blood cells
What are common symptoms of food poinsoning
Vomiting Dizziness Muscle weakness Nausea Abdominal cramping Diarrhoea
What are RIP’s
Ribosome inactivating proteins
Catalytic toxins
E.g Ricin
Inhibit protein synthesis in target cell
Which of the following is not true of RIP’s
- Commonly found in castor beans
- Fatal at low doses
- Soaking will release ricin content to safe levels
- Present in barley, rye, wheat germ
- Affect host cell transport systems
Affect host cell transport systems
RIPs are split into two parts. Part 1: Inhibiting protein synthesis.
2: mediate entry to the cell
What are the differences between bacterial infection and bacterial intoxication
Infection Live cell consumed Long onset time Long lived Puritanical (fever) response
Intoxication Viable cells may not be present Rapid onset Short duration Usually not pyrogenic
Define: endotoxins
- generally cell bound
- released in large amounts upon cell lysis
Define: exotoxins
Released from the cell as it grown
Often enzymes
Define: enterotoxin
Specifically toxic to cells of the digestive tract
Causes characteristic r&b associated with food poinsoning
Which of the following is true if campylobacter
Most common form of food poinsoning
Little is known of it
Positive for cytolethal distending toxin
Hinders host Immune response
All
How does salmonella work
Secretes toxins which tricks the host cell into endocytosing it
Bacterial cell loves inside host cell
Produces enterotoxin
What’s the difference between emetic and diarrhoeal enterotoxin
Emetic affects the cns and are typically acid and heat stable therefore can act in the guy
Diarrhoeal are sensitive to heat and digestive proteases
