Why is Alexandrium spp harmful?
By producing potent neurotoxins, known as saxitoxins (STXs), A. fundyense is responsible for outbreaks of paralytic shellfish poisoning (PSP), which is potentially fatal to humans (Llewellyn, 2006).
What toxins does Alexandrium produce?
The dinoflagellate alga Alexandrium fundyense produces a suite of potent neurotoxins (saxitoxin and its derivatives) resulting in Paralytic Shellfish Poisoning (PSP). PSP is known to impair physiological functions in bivalve molluscs and copepods.
What causes Alexandrium blooms?
Alexandrium blooms occur seasonally and are influenced by a multitude of abiotic conditions from temperature, salinity, nutrient availability and even weather patterns. They also are impacted by biological factors including predation, infection from viruses, bacteria, parasites or cell encystment.
Is Alexandrium a Catenella an algae?
catenella is categorized as a harmful algal bloom (HAB) species. Alexandrium catenella’s multiplication is stimulated by higher ammonia and inorganic nitrogen concentrations. The optimal growth conditions for A.
What do alexandrium Catenella eat?
The toxin is produced by dinoflagellates such as Protogonyaulax sp., Gymnodium catenatum, Alexandrium catenella and Alexandrium minutum. Mussels, clams and oysters feed on these dinoflagellates or red algae with which they may be associated and thus become toxic.
What does alexandrium Fundyense need to grow?
A. fundyense rely on nitrogen and phosphate nutrients to grow (13).
Where are algae blooms the worst?
The most well known harmful algal bloom (HAB) on the east coast is Alexandrium catenella, also known as the Gulf of Maine “red tide.” This toxic dinoflagellate produces saxitoxins that can accumulate in shellfish and cause paralytic shellfish poisoning in human consumers. It occurs from Maine to New York.
Where is alexandrium Fundyense from?
Alexandrium fundyense grows primarily in low-salinity, marine environments during the spring and summer months. The highest concentrations of Alexandrium cells are generally seen near the surface waters of the Gulf of Maine.
What do alexandrium Fundyense need to grow?
Is there a cure for paralytic shellfish poisoning?
There is no antidote for Paralytic Shellfish Poison. The only treatment for severe cases is the use of life support systems such as a mechanical respirator and oxygen until the toxin passes from the victim’s system. Survivors can have a full recovery.
How do you treat mussel poisoning?
There is no specific cure available for shellfish poisoning, and antibiotics do not shorten the illness. Drugs used to control diarrhea, vomiting, and stomach cramps should not be used except for bismuth (Pepto-Bismol). These drugs are referred to as antimotility drugs since they decrease stomach and intestine motion.
What is the function of Alexandrium?
Some species of Alexandrium are colonial organisms. For example, Alexandrium catenella is a catenate (chain-forming) organism. Alexandrium produce paralytic shellfish poisoning toxins (PST). PSTs are neurotoxins. They inhibit transmisison of nerve impulses by blocking sodium channels.
Is Alexandrium a colonial organism?
Some species of Alexandrium are colonial organisms. For example, Alexandrium catenella is a catenate (chain-forming) organism. Alexandrium produce paralytic shellfish poisoning toxins (PST). PSTs are neurotoxins.
How do you identify Alexandrium species?
DNA sequencing is one of the most popular ways to identifiy different Alexandrium species. Diagram of life cycle. By Jack Cook, Woods Hole Oceanographic Institution. Alexandrium species are considered armored dinoflagellates, because they are covered with thecal plates. Alexandrium have two flagella.
Are all Alexandrium species dangerous to humans?
Many Alexandrium species are toxic, which can cause both medical and economic harm to humans. The non-toxic species can cause trouble as well. DNA sequencing is one of the most popular ways to identifiy different Alexandrium species.