Membrane fragments from electric tissue of Torpedo californica containing nicotinic acetylcholine receptor are composed of four different polypeptide chains with molecular weights of 40,000 (alpha), 48,000 (beta), 62,000 (gamma), and 66,000 (delta). The alpha and beta chains are still present in all and gamma and delta in some of the receptor preparations after Triton X-100 extraction and purif...

Three defensin-like peptides (DLPs) were isolated from platypus venom and sequenced. One of these peptides, DLP-1, was synthesized chemically and its three-dimensional structure was determined using NMR spectroscopy. The main structural elements of this 42-residue peptide were an anti-parallel beta-sheet comprising residues 15-18 and 37-40 and a small 3(10) helix spanning residues 10-12. The ov...

Introduction: Although aging is the most important risk factor for Alzheimer's disease (AD), there is evidence indicating that neuroinflammation may contribute to the development and progression of the disease. Several studies indicated that minocycline may exert neuroprotective effects in rodent models of neurodegenerative diseases. Nevertheless, there are also other studies implying that ...

In the present study, BmK alphaIV, a novel modulator of sodium channels, was cloned from venomous glands of the Chinese scorpion (Buthus martensi Karsch) and expressed successfully in Escherichia coli. The BmK alphaIV gene is composed of two exons separated by a 503 bp intron. The mature polypeptide contains 66 amino acids. BmK alphaIV has potent toxicity in mice and cockroaches. Surface-plasmo...

Introduction: The design and structural characterization of mini-proteins with a compact, folded structure provide insight into the complex architecture of proteins today and has long been a challenging issue in structural- functional studies. Alpha neurotoxins from snake venom have a distinct folded structure comprised of a disulphide core and three loops or “fingers” each of these loops are c...

The hemagglutinating protein HA33 from Clostridium botulinum is associated with the large botulinum neurotoxin secreted complexes and is critical in toxin protection, internalization, and possibly activation. We report the crystal structure of serotype A HA33 (HA33/A) at 1.5 A resolution that contains a unique domain organization and a carbohydrate recognition site. In addition, sequence alignm...

Scorpion venom is the richest source of peptide toxins with high levels of specific interactions with different ion-channel membrane proteins. The present study involved the amplification and sequencing of a 310-bp cDNA fragment encoding a beta-like neurotoxin active on sodium ion-channel from the venom glands of scorpion Androctonus crassicauda belonging to the Buthidae family using r...

Botulinum neurotoxins produced by Clostridium botulinum cause flaccid paralysis by inhibiting neurotransmitter release at peripheral nerve terminals. Previously, we found that neurons derived from the murine P19 embryonal carcinoma cell line exhibited high sensitivity to botulinum neurotoxin type C. In order to prove the utility of P19 cells for the study of the intracellular mechanism of botul...

Snake venoms are a mixture of pharmacologically active proteins and polypeptides that have led to the development of molecular probes and therapeutic agents. Here, we describe the structural and functional characterization of a novel neurotoxin, haditoxin, from the venom of Ophiophagus hannah (King cobra). Haditoxin exhibited novel pharmacology with antagonism toward muscle (alphabetagammadelta...

The previously characterized ( Rehm , H., and Betz, H. (1982) J. Biol. Chem. 257, 10015-10022) neuronal binding protein for the presynaptic neurotoxin beta-bungarotoxin (beta-BuTx) was solubilized from synaptic membrane fractions of chick brain using the nonionic detergent Triton X-100. 125I-beta-BuTx bound to the solubilized protein with a dissociation constant (KD) of 1.9 +/- 0.1 nM. This bin...