Micro quiz 111210

• like leukocidin
• does not kill phagocytes
• interferes with the ability of phagocytes to phagocytize cells

• present in staphylococci
• action: digests lipids
• purpose: helps the bacteria to colonize oily skin

• aka DNase
• present in staphylococci
• action:digests DNA
• purpose: destroy leukocytes

• present in many different species, especially staphylococci and streptococci
• action: cleaves members of the penicillin drug family
• purpose: confers resistance to beta lactam antibiotics

• work on peptidoglycan preventing cell wall synthesis, ultimately leading to cell death
• allows infection to persist

• present in Entamoeba histolytica
• enzyme digests the protective coating on mucous membranes
• is a virulence factor in amebic dysentery

• digest keratin-principal component of skin and hair
• present in dermatophytes (fungal species that reside in the epidermal layer of the skin)
• organisms cause superficial cutaneous infection
• ex. ring worm (tinea)

• powerful fungi toxins
• infections results form ingestion of poisonous
• species
• more than 400 mycotoxins. 150 species of fungi
• effects: hallucinations, emesis, diarrhea, coma, death
• ex. Aspergillus, Penicillium, Fusarium, Stachbotrys

• one of the most potent fungal toxin
• occur in nuts, grains and cereals under conditions of high temperature and high humidity
• consist of 10 types: B&G
• target: liver damage and cancer of liver (jaundice, hepatitis, hepatic cancer)
• produced by:Aspergillus flavus and Aspergillus parasiticus
• B1 is considered the most potent naturally-occuring hepatocarcinogen

B aflatoxins

B and G aflatoins

• liver damage
• aflatoxin

• cancer of the liver
• aflatoxin

• nausea
• emesis
• abdominal pain
• diarrhea
• cerebral edema
• permanent brain damage

• Mycotoxin
• produced by Aspergillus versicolor, Aspedillus flavus, Aspergillus parasiticus
• considered a precursor to aflatoxins

• produced by Aspergillus and Penicillium
• found on cereals, coffee and bread
• most frequent contaminating mycotoxin in the world
• A is the most toxic (nephrotoxic, nephropathogenic, immunosuppressive, carcinogenic, tetratogenic)
• linked to idiopathic nephropathies
• linked to rare tumors of the pelvis and ureter

• ochratoxin
• fatal renal disease in rural populations of Croatia, Bosnia, Bulgaria, and Romania

• produced by Claviceps
• present on the surface of grain
• 40 types
• divide in 3 main groups: lysergic acid, isolysergic acid, dimethylergoline
• result in ergotism
• gangrenous form
• convusive ergotism

• Toxins constrict blood vessels and impair circulation
• Affect CNS (neurotoxic effect)
• Hallucinations and convulsions
• Loss of mental function
• Spasms and cramps
• Paresthesia in calves and/or edema of the legs
• Paresthesia: an abnormal touch sensation; feelings of burning or prickling in the absence of an external stimulus; Tingling or burning sensations
• Feelings of intense cold
• Can result in gangrene; this may require amputation

• Gastroenteritis (nausea and emesis)
• Dizziness
• CNS symptoms:
• Drowsiness
• Prolonged sleepiness
• Twitching
• Convulsions
• Paralysis
• Blindness

• Ergot Alkaloids
• e.g. ergotamine, ergocristine

e.g. ergotaminine

e.g. agroclavine

an abnormal touch sensation; feelings of burning or prickling in the absence of an external stimulus; Tingling or burning sensations

• produced by Fusarium, Trichoderma, Trichothecium, Mycrothecium, Stachybotyrs
• associated with contaminated rice or wheat
• more than 150
• divided into 4 classes: T1-T4
• example: Vomitoxin, Nivalenol, T-2 toxin
• extremely toxic: causes cytolysic and necrosis, results in blistering lesions. prevents mitosis of cells lining the intestine and bone marrow cells

• Abdominal pain
• Nausea
• Emesis
• Heachache
• Dizziness and vertigo
• Fatigue
• Fever/Chills
• Diarrhea

• Produced by Fusarium moniliforme
• Grow on corn (maize)
• Two main types: A and B
• A (1-2) and B (1-4)
• B1 and B2 are most toxigenic
• Considered a carcinogen
• Associated with esophageal cancer

• Toxin: alpha-amanitin
• Made by different species of Amanita
• e.g. Amanita phalloides
• Deadliest mushroom
• Common name
• Death cap
• Contains enough toxin in the cap of the mushroom to kill an adult

• Deadliest mushroom
• Common name: Death cap
• Contains enough toxin in the cap of the mushroom to kill an adult

• Produced by Stachybotrys chartarum
• Typical symptoms include: irritation of the mouth, lips, nose and throat
• Can progress to leukopenia and ulceration of the mucosal surfaces of the nose and throat and lungs
• Presented as a possible etiological agent for acute idiopathic hemorrhage in infants (not conclusive)

• Also called cyanotoxins
• Microcystin
• Anatoxin-a
• Cylindrospermopsin
• Domoic acid

• Are hepatotoxins
• Toxin targets the liver
• Most commonly detected cyanotoxin in fresh water or brackish water
• Produced by Microcystis and related species
• Toxin cannot penetrate directly into animal membranes
• Uptake through cell membrane transporters
• Are heat stable
• Linked to liver cancer in humans

• Two main types: Anatoxin-a & Anatoxin-as
• Are neurotoxins
• Result in paralysis, respiratory distress, asphyxiation, convulsions and death
• Are alkaloids
• Are susceptible to breakdown by sunlight

• Some diatoms produce a toxin called domoic acid
• Until recently, diatoms were thought not to produce toxins
• Causes amnesic shellfish poisoning which results in the loss of short term memory
• Symptoms: loss of memory, nausea, vomiting, diarrhea, and abdominal cramps

• dinoflagellate
• Produced by Karenia brevis
• This dinoflagellate causes red tides
• Disease is called neurotoxic shellfish poisoning.
• Fish eat dinoflagellate→ Humans eat fish→ food poisoning

• A tingling sensation in the mouth and fingers (paresthesia)
• Dizziness
• Ataxia: extreme lack of coordination
• Myalgia: muscle pain
• GI symptoms: diarrhea, vomiting, abdominal pain
• Symptoms are mild and self-limiting

• dinoflagellate
• Produced by Gonyaulax catenella
• This organism also makes the toxin gonyautoxin
• Both of these toxins are neurotoxins
• Considered very potent toxins
• Disease is called paralytic shellfish poisoning
• Shellfish (clams, oysters, mussels) eat dinoflagellate→humans eat shellfish→paralytic shellfish poisoning

• This organism also makes the toxin gonyautoxin
• Both of these toxins are neurotoxins
• Considered very potent toxins

• Mild form
• General numbness: mouth, lips, face and extremities (paresthesia)
• GI symptoms: nausea, vomiting, diarrhea and abdominal pain

• Severe form
• General muscle weakness
• Ataxia: lack of coordination; difficulty walking
• Dysphonia: difficulty speaking
• Dysphagia: difficulty swallowing
• Respiratory failure: Impaired respiration from muscle paralysis
• Death can result from respiratory failure

• dinoflagellate
• One of the most powerful toxins known
• Produced by Gambierdiscus toxicus
• Disease is called ciguatera (fish poisoning)
• Fish eat dinoflagellate→Humans eat fish→Food poisoning
• Toxin is heat stable and remains in flesh of fish even after the fish has been cooked

• GI symptoms: vomiting, profuse diarrhea, abdominal pain
• Reversal of cold and hot sensations (e.g.: ice-cream tastes hot, coffee tastes cold)
• Bradycardia: reduced pulse rate; heart beat slows to less than 60 beats per minute
• Myalgia: specifically, pain and weakness in the lower extremities
• Coma and Respiratory failure (in severe cases)

• Produced by Pfiesteria piscicida
• Complex life cycle; has 24 intermediate forms
• Produces two toxins: one toxin stuns fish & other toxin causes lesions on the fish
• Organism feeds on the fish’s red blood cells which allows it to sexually reproduce

• Prolonged amnesia
• Confusion
• Headaches
• Muscle cramps
• gastrointestinal complaints
• Also bloody skin lesions in humans exposed to the toxins at the point of contact with infected fish