Lec. 3 Fungi & Algae Flashcards
Hundreds Of Dead Seabirds, Sea Lions Wash Up In Southern California
- The likely culprit is a toxic algal bloom, fueled by warmer ocean temperatures.May 31, 2017
- this happens cuz of the weather and the accumulation of fertilizer
- Alaska shellfish farms temporarily shuttered due to deadly toxin
- Shellfish may contain toxins even in winter months
ALGAE
- “Algae” is used broadly to mean anything photosynthetic that lives in water
- No common taxonomic relationship among organisms called algae;
–includes both eukaryotic and prokaryotic organisms
–Both unicellular (microscopic) and multicellular (macroscopic) species
BASIC CHARACTERISTICS OF DINOFLAGELLATE ALGAE
- Unicellular, eukaryotic organisms
- Live mainly in marine water or nearby beach sand (that is wet);
- Cells contain chloroplasts which perform photosynthesis (autotrophic); May have other pigments that mask green color, but usually green
- Have two flagella, one propelling forward and one sideways
- Have cell walls made of cellulose, often as thick plates;
- Form cysts for protection
- Reproduction is asexual by binary fission (similar to mitosis, but they don’t call it that for single celled organisms) … process of dividing
Pseudo-nitzschia
domoic acid (extremely toxic poison causing Amnesic]), amnesic shellfish poisoning
Alexandrium
saxitoxin, paralytic shellfish poisonin
Harmful Microalgae
Dinoflagellates causing shellfish poisoning produce toxins into water
DINOFLAGELLATE TOXINS
- Have complex chemical compsitions
- Are neurotoxins
-they are not present in freshwater
HOW ARE HUMAN EXPOSED TO TOXINS PRODUCED BY DINOFLAGELLATES?
- Swallowing small amounts of water containing the toxin while swimming
- Eating shellfish in which the toxin has a higher concentration
- Shellfish are aquatic invertebrates with an exoskeleton
-each toxin is produce by a certain species
SHELLFISH/FISH POISONING SIGNS/SYMPTOMS
- For all types: Onset within 10-30 min. after eating contaminated shellfish; numbness tingling in mouth
- Diarrhetic - causes diarrhea, nausea, vomiting
- Neurotoxic - slurred speech, nausea, vomiting
- Paralytic - parathesias, loss of coordination, death
- Amnesic - permanent loss of short term memory, death
- Ciguatera fish poisoning - gastrointestinal and neurological impairment
TREATMENT OF SHELLFISH POISONING
- Induce vomiting and/or pump stomach to get rid of as much toxin as possible
- Feed charcoal to victim to adsorb the toxins
- Provide mechanized breathing assistance if respiratory muscles are paralyzed
- No antidote has been discovered that counteracts effects of the toxins
STATISTICS ON SHELLFISH/FISH POISONINGS
- USA – each year ≈30 cases; 1 death ≈every 4 years
* Globally – 100,000 cases/year; 1.5% death rate
PREVENTION OF SHELLFISH POISONING
- inspection/testing
- warnings
- educatopm
- thorough cooking does NOT prevent shellfish poisoning
Consumers Advised To Not Eat Rock Crabs, Bivalve Shellfish Caught Along Monterey Bay, Peninsula
- Dangerous levels of toxin domoic acid (amnesic shellfish poisoning) found in rock crabs, oysters, clams, mussels and scallops, CA Department of Health said.
- Shellfish monitors keep tabs on deadly toxins
CHARACTERISTICS OF ALL FUNGI
- Eukaryotic cellular structure
- Cells do not contain chloroplasts and do not perform photosynthesis; they are heterotrophic
- Most species have cell walls containing chitin
- Both unicellular (microscopic) and multicellular (macroscopic) species (mushrooms) exist
-morphology of the fungi is very important for fungi identification of diseases
FUNGAL CELL WALLS
- Mannan
- B-Glucan
- Chitin (KEY MOLECULE IN THE CELL WALL OF THE FUNGI)
YEAST
•A single or two-cell form of fungus
•Reproduces by budding (daughter cell buds from mother cell) (small cell attached to a larger cell)
CHECK SLIDE 23
MOLD
•A multicellular fungus
•Cells joined together in a filamentous structure (hypha, pl. hyphae)
–septate (with walls separating cells)
–aspetate (without cross walls separating cells) (nonseperate hyphae) check slide 24
•A mycelium is a collection of hyphae
–Vegatative mycelium grows into a source of nutrients
–Aerial mycelium grow up into the air
•A colony occurs when the mycelium grows and becomes visible to naked eye
MOLD REPRODUCTION
- Mold reproduction is primarily asexual, especially for the species that cause human disease
- Reproductive units are produced by aerial mycelia and dispersed by winds, animals etc.
•There are two types of asexual reproductive units:
–Conidia
–Sporangiospores
DIMORPHIC FUNGI HAVE BOTH A YEAST AND A MOLD PHASE
–Mold (saprophytic) phase is in the soil
•Specific species are in specific geographic locations
•Grows at <37°C. (body temperature)
–Yeast (parasitic) phase occurs (the phase where humans get sick) in a human/animal after conidia are inhaled from the soil
•Temperature must be ≥37°C. for conversion to yeast phase
•Causes disease in some infected humans
–Yeast phase cannot be transmitted from one human to another
WHO GETS FUNGAL INFECTIONS (MYCOSES)?
•Minor fungal infections:
–Occur in most people constantly
–Are self-limiting
•Severe life-threatening fungal infections:
–occur primarily in immunosuppressed persons
•Due to medications
•Due to underlying diseases, e.g. AIDS
–Are increasing in frequency because more people are immunosuppressed
DISTRIBUTION OF SHELLFISH POISONING
Along the west coast and east coast of USA
ARE RED TIDES ASSOCIATED WITH SHELLFISH POISONING?
no, but they can be present in there
GEOGRAPHICAL DISTRIBUTION OF HISTOPLASMA CAPSULATUM
- CHECK SLIDE 32
- likes to grow in areas with a lot of bird poop
CHEST X-RAY OF HISTOPLASMA CAPSULATUM INFECTION
You can see the cloudy dots that show the infection
- professor has this in her chest, but it is in graduloma or algo asi so its okay…
- as long as it stays incased in the granduloma then you chilling B
- there is medication to treat it
GEOGRAPHICAL DISTRIBUTION OF COCCIDIOIDES IMMITIS (Valley fever)
- central valley and south west
- dust storm in phoenix, AZ, 2008
- this is cuz its dry and the wind blows around
- will also see granulomas in the lungs… nothing bad happens to people (unless they have week immunology) cuz they body can bounce back
GEOGRAPHICAL DISTRIBUTION OF BLASTOMYCES DERMATITIDIS
mid east
- does dimesminate in the blood
- can be all over the body
- it is treatable
- skin is most likely place to have an effect
