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Black Mamba Snake Venom. Ifeoma Romaine Tamara Brooks. The Snake. Fastest snake in the world (4) speeds up to 12 mph 2 nd largest venous snake in the world (4) Average length – 8 ft. Longest length – 14 ft. Found in Sub-Saharan Africa. Tan areas indicate area where Black Mamba is found.
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Black Mamba Snake Venom Ifeoma Romaine Tamara Brooks
The Snake • Fastest snake in the world (4) • speeds up to 12 mph • 2nd largest venous snake in the world (4) • Average length – 8 ft. • Longest length – 14 ft. • Found in Sub-Saharan Africa Tan areas indicate area where Black Mamba is found
The Snake • Classification (4) • Kingdom: Animalia • Phylum: Chordata • Class: Reptilia • Order: Squamata • Suborder: Serpentes • Family: Elapidae • Genus: Dendroaspis • Species: D. polylepis
The Snake Are olive, brown, gray, or sometimes khaki with a cream underbelly Named for color of lining inside mouth (4) Found in low, open habitats, rocky places or open woodlands
The Snake • Breed once a year (5) • No other interaction besides breeding and female abandons eggs after laying them (5) • Oviparous with young fully functional upon hatching (5)
The Strategy • Avoid confrontation but become aggressive when threatened.(5) • Raise head up to 1 meter off the ground (5) • Rapid, numerous strikes followed by flee (5) • Depends on reason of bite
The Strategy • Diurnal and hunts both during the day and at night (4) • When hunting small animals, it delivers one bite then allows venom to take over (4) • Stalks prey until death • When hunting birds, clings to animal to prevent it from flying away (4)
LD50 of 0.25-0.32 mg/kg One bite delivers 100-120mg on average Maximum 400 mg 10 to 15 mg is deadly to a human adult Contains Calciseptine Toxin 1 Toxin K The Venom
The Dendrotoxin • Dendrotoxin Two: long and short chain “toxin k” (2) 57 Amino acid sequence (short) (2) 59 or 60 in the long Highly specific (6) Dendrotoxin in channel
The Dendrotoxin Mechanism • Potassium channel blocker(1) • Specific blocker of non-inactivating Kv1.1, voltage gated K+ channels (1) • Facilitate Ach release from the presynaptic membrane(2) • Kv1.1 channels produce sustained outward potassium currents in response to low changes in membrane potential away from resting (3)
The Dendrotoxin Mechanism • The blockage of potassium channels prevent the repolarization of nerve and muscle cells • Increases the release of neurotransmitters • Prevents the relaxation of muscle cells
Calciseptine • Natural peptide consisting of 60 amino acids with four disulfide bonds. (6) • Highly selective antagonist or agonist
Calciseptine Mechanism • Agonist in skeletal muscle • Increases amplitude of action potentials • Antagonist in cardiac and smooth muscle • Blocks K+ induced contraction in aortic smooth muscle • Blocks spontaneous contraction of uterine muscle and portal vein.
Calciseptine Mechanism • Blocks both Ca2+ and Na+ modes of L-type Ca channel • responsible for normal myocardial and vascular smooth muscle contractility.
L Type Ca2+ Channel • L Type Calcium Channel (7) • Long-lasting voltage-gated Calcium Channels are found in both excitable and non-excitable tissue. • They are responsible for normal myocardial and vascular smooth muscle contractility. • Blockage can abolish contractions in cardiac and smooth muscle
Five subunits make up the L-type channel and alpha-1 subunit is the binding site for calcium-based antagonists (6) Two distinct functions: as voltage sensors, regulate the release of Ca2+ by the sarcoplasmic reticulum (6) Channels are permeate to Ca2+ giving rise to very slowly activated Ca2+ currents (6) L Type Ca2+ Channel
The Relevance • One of the most dangerous snakes (5) • venom can kill within 20 minutes • Combination of speed, unpredictable aggression, and potent venom (5) • Help control pest population eat small rodents (5)
Conclusion • Not an endangered species, but problem of humans imposing on habitat (5) • Venom is toxic to about everything. (5) • Venom can induce the failure of major organ systems and eventually cause death
The Trivia • Nike’s “Air Jordan XIX” were designed after this snake (4) • Polymers used to cover laces resemble black snake skin • The 1982 British horror film "Venom" (starring Klaus Kinski) featured a black mamba, delivered to a young boy by mistake, and set loose in his house just as a kidnap plot went awry (4)
The Trivia • Uma Thurman's character Beatrix Kiddo in the Kill Bill movie series has the codename "Black Mamba" - all DiVA members have snake codenames. The character of Budd was killed by a black mamba planted in a suitcase full of money. As he lay dying, Elle Driver, the one responsible for planting the snake, reads to him a compilation of facts about the snake's venom (4)
References (1)Calbiochem. www.emdbiosciences.com/Shared images. Downloaded May1, 2007. (2) Errington, Adam C., Thomas Stohr, and George Lees. Voltage Gated ion Channels: Targets for Anticonvulsant Drugs. Current Topics in Medicinal Chemistry. Vol 5: 15-30. (3) Imredy, John P., and Rodercik Mackinnon. Energetic and Structural Interactions between δ-Dendrotoxin and a Voltage-gated Potassium Channels. 2000. Journal of Molecular Biology. Vol. 296:1282-1294. (4) Mamba. http:/./en.wikipedia.org/wiki/Mamba. Downloaded May 2, 2007. (5) Schott, Randy. Dendroaspis polylepis. www.animaldiversity.ummz.umich.edu/site/accounts/info. Downloaded May 2, 2007. (6) Garcia, M.C, et. al., Calciseptine, a Ca2+ Channel Blocker, Has Agonist Actions on L-type Ca2+ Currents of Frog and Mammalian Skeletal Muscle. 2001. Journal of Membrane Biology. Vol 184: 121-129 (7) L-Type Calcium Channel. http://www.online-medical-dictionary.org/L+Type+Calcium+Channel.asp?q=L+Type+Calcium+Channel