| variability among the sites by which curaremimetic toxins bind to torpedo acetylcholine receptor, as revealed by identification of the functional residues of alpha-cobratoxin. | alpha-cobratoxin, a long chain curaremimetic toxin from naja kaouthia venom, was produced recombinantly (ralpha-cbtx) from escherichia coli. it was indistinguishable from the snake toxin. mutations at 8 of the 29 explored toxin positions resulted in affinity decreases for torpedo receptor with deltadeltag higher than 1.1 kcal/mol. these are r33e > k49e > d27r > k23e > f29a >/= w25a > r36a >/= f65a. these positions cover a homogeneous surface of approximately 880 a(2) and mostly belong to the sec ... | 1999 | 10574958 |
| "weak toxin" from naja kaouthia is a nontoxic antagonist of alpha 7 and muscle-type nicotinic acetylcholine receptors. | a novel "weak toxin" (wtx) from naja kaouthia snake venom competes with [(125)i]alpha-bungarotoxin for binding to the membrane-bound torpedo californica acetylcholine receptor (achr), with an ic(50) of approximately 2.2 microm. in this respect, it is approximately 300 times less potent than neurotoxin ii from naja oxiana and alpha-cobratoxin from n. kaouthia, representing short-type and long-type alpha-neurotoxins, respectively. wtx and alpha-cobratoxin displaced [(125)i]alpha-bungarotoxin from ... | 2001 | 11279130 |
| human monoclonal scfv neutralize lethal thai cobra, naja kaouthia, neurotoxin. | animal derived anti-naja. kaouthia (thai cobra) venom is used for specific treatment of the snake bitten victims. many recipients develop allergic reaction or anti-isotype response which causes serum sickness. a better therapeutic antibody is needed. in this study, long alpha-neurotoxin was purified from the n. kaouthia holovenom and verified by 2d-lc/ms-ms. the toxin was used as antigen in a phage bio-panning to select phage clones displaying human single chain variable antibody fragments (husc ... | 2009 | 19162253 |
| bacterial production and refolding from inclusion bodies of a "weak" toxin, a disulfide rich protein. | the gene for the "weak" toxin of naja kaouthia venom was expressed in escherichia coli. "weak" toxin is a specific inhibitor of nicotine acetylcholine receptor, but mechanisms of interaction of similar neurotoxins with receptors are still unknown. systems previously elaborated for neurotoxin ii from venom of the cobra naja oxiana were tested for bacterial production of "weak" toxin from n. kaouthia venom. constructs were designed for cytoplasmic production of n. kaouthia "weak" toxin in the form ... | 2009 | 19916927 |
| humanized-single domain antibodies (vh/vhh) that bound specifically to naja kaouthia phospholipase a2 and neutralized the enzymatic activity. | naja kaouthia (monocled cobra) venom contains many isoforms of secreted phospholipase a2 (spla(2)). the pla(2) exerts several pharmacologic and toxic effects in the snake bitten subject, dependent or independent on the enzymatic activity. n. kaouthia venom appeared in two protein profiles, p3 and p5, after fractionating the venom by ion exchange column chromatography. in this study, phage clones displaying humanized-camel single domain antibodies (vh/v(h)h) that bound specifically to the p3 and ... | 2012 | 22852068 |