Disease relevance of Elapidae

• Hence, utilizing a constructed cDNA library from the venom glands of the black mamba (Dendroaspis polylepis), the gene encoding dendrotoxin K was isolated, amplified, and expressed as a maltose-binding fusion protein in the periplasmic space of Escherichia coli [1].
• This report describes two accidents, involving snakes of the Micrurus corallinus species, where compromising respiratory function was not observed and the specific anti-elapidic serum was the single therapy used, and a third incident, probably involving Micrurus frontalis, where neostigmine was used to remedy respiratory failure [2].
• External ophthalmoplegia in elapidae bites and its response to neostigmine [3].
• The neurotoxic venoms (represented chiefly by the non-spitting cobras and mambas) cause high mortality due to rapid onset of paresis and require antivenom and mechanical ventilatory support which is life-saving [4].

High impact information on Elapidae

• Toxins from mamba venoms: small proteins with selectivities for different subtypes of muscarinic acetylcholine receptors [5].
• Muscarinic toxin 7 (MT7) is a mamba venom protein antagonist with extremely high selectivity for the M1 muscarinic acetylcholine receptor [6].
• Expression and activity of mutants of fasciculin, a peptidic acetylcholinesterase inhibitor from mamba venom [7].
• Dendroaspis natriuretic peptide (DNP) relaxed aortic strips that had been contracted by 40 mM KCl with a potency (K0.5 = 20 nM) similar to that of atrial natriuretic peptide (ANP) and larger than that of C type natriuretic peptide (CNP) [8].
• Dendrotoxin K from black mamba venom provides a good model to test this, since it contains the BPTI fold and was shown to fold predominantly via the same pathway, but its native conformation is stable than that of BPTI [9].

Biological context of Elapidae

• The mechanism of binding of toxin MT2 from venom of green mamba Dendroaspis angusticeps to muscarinic acetylcholine receptors from rat cerebral cortex was investigated by studying the kinetics of the toxin-receptor interaction [10].
• The amino acid sequences of four presynaptically active toxins from mamba snake venom (termed 'dendrotoxins') were compared systematically with homologous sequences of members of the proteinase inhibitor family (Kunitz) [11].
• The interaction of these binding sites with those for dendrotoxin (a convulsant polypeptide from mamba venom) and mast-cell-degranulating peptide (from bee venom) was examined in the light of the known effects of all three toxins on voltage-dependent K+ currents [12].
• This is the first nucleotide sequence of a Factor V-like component from Oxyuranus venom and the second sequence within Elapidae to be reported [13].

Anatomical context of Elapidae

• The epileptogenic and neurodegenerative effects of dendrotoxin K (DTx-K), from Dendroaspis polylepsis, a specific blocker of a noninactivating, voltage-sensitive K+ channel, were studied after focal injection into one dorsal hippocampus in rats pretreated with the 21-aminosteriod U-74389G, a scavenger of free oxygen radicals [14].
• 1 The venom of the green mamba, Dendroaspis angusticeps, was tested for effects on neuromuscular transmission and skeletal muscle contractility in isolated phrenic nerve-hemidiaphragm preparations of the rat and mouse, chick biventer cervicis muscle preparations and in aneural cultures of embryonic chick skeletal muscle [15].
• Labeling of M2-M5 muscarinic receptors using [3H]N-methyl-scopolamine (NMS) by occluding various receptor subtypes with muscarinic antagonist and mamba venom resulted in the labeling of M2-M5 receptors in brain as well as in human peripheral blood lymphocytes [16].
• Dendrotoxin from the venom of the green mamba, Dendroaspis angusticeps. A neurotoxin that enhances acetylcholine release at neuromuscular junction [17].
• The inhibition of locus coeruleus (LC) acetylcholinesterase (AChE) by Fasciculin II (FAS), a novel anticholinesterase peptide from the green mamba (Dendroaspis angusticeps) venom, was studied in rats [18].

Associations of Elapidae with chemical compounds

• The pathways of the homologous proteins I and K from black mamba venom were determined here, using the disulphide interaction between their six cysteine residues to trap and identify the intermediate states, and are compared with those determined previously in the same way for the homologous bovine pancreatic trypsin inhibitor [19].
• Muscarinic toxin 2 from Dendroaspis angusticeps has been crystallized by vapour diffusion, in sodium acetate using sodium thiocyanate as a precipitant [20].
• PLIgamma was a 100-kDa glycoprotein containing 25-kDa and 20-kDa subunits and inhibited all of the PLA2s investigated equally, including Elapidae venom PLA2s (group I), Crotalidae and Viperidae venom PLA2s (group II) and honey-bee PLA2 (group III) [21].
• Comparative molecular modelling study of the calcium channel blockers nifedipine and black mamba toxin FS2 [22].
• 2 Dendrotoxin from the Eastern green mamba (Dendroaspis angusticeps) and toxins K and I from the black mamba (Dendroaspis polylepis polylepis) increased to indirect stimulation without affecting responses to exogenous acetylcholine, carbachol of KCl [23].

Gene context of Elapidae

• Pharmacological investigation of the electrophysiological properties of Kv1.1 demonstrated that the mamba snake toxin dendrotoxin-K (DTX-K) blocked the Kv1.1 outward current when expressed as a homotetrameric complex (EC(50) = 0.34 nM) [24].
• The present study used isolated rat hearts to investigate whether (1) Dendroaspis natriuretic peptide (DNP) is protective against post-ischemic myocardial dysfunction, and (2) whether the cardioprotective effects of DNP is related to alteration of Bcl-2 family protein levels [25].
• BACKGROUND: Fasciculin (FAS), a 61-residue polypeptide purified from mamba venom, is a three-fingered toxin which is a powerful reversible inhibitor of acetylcholinesterase (AChE) [26].
• The amino acid sequence was homologous with those of PLA2S from Elapidae venoms [27].
• We studied the action of the muscarinic toxins MT1, MT2 and MT3, from the venom of the snake Dendroaspis angusticeps, on muscarinic receptors, by using the classical muscarinic radioligand 3H-NMS as reporter of the inhibition of its own binding, to either native or cloned receptors [28].

Analytical, diagnostic and therapeutic context of Elapidae

• The cardiotoxic actions of Kenyan green mamba (Dendroaspis angusticeps) venom have been investigated using primary myocardial cell cultures isolated from neonatal rat hearts [29].
• Primary cultures of spontaneously beating myocardial cells isolated from neonatal rat hearts were used to screen the cardiotoxic effects of Jamesoni's mamba (Dendroaspis jamesoni) venom and components isolated from the venom by gel filtration and ion exchange chromatography [30].
• Two protein toxins that displace the muscarinic antagonist quinuclidinyl benzilate from rat cortex synaptosomal membranes have been isolated from the green mamba (Dendroaspis angusticeps) venom by gel filtration on sephadex G-50, chromatography on the ion-exchangers Bio-Rex 70 and Sulphopropyl-Sephadex C-25 and reversed-phase HPLC [31].

References