Showing papers on "Naja published in 1982"
TL;DR: Prey capture behavior between cottonmouths and Egyptian cobras differ fundamentally in response to proximate factors and Cottonmouths, when presented with several mice in close succession, tended to release the first mice but hold on to later mice.
Abstract: Prey capture behavior between cottonmouths (Agkistrodon piscivorus) and Egyptian cobras (Naja haje) differ fundamentally in response to proximate factors. Cottonmouths, when presented with several mice in close succession, tended to release the first mice but hold on to later mice. Cottonmouths, too, were more deliberate in establishing coils from which to strike than the cobra. In the Egyptian cobra, there was no appreciable change in hold/release behavior through a sequence of up to 4 mice. More important was the retaliation of the mouse when struck. Egyptian cobras usually held a struck mouse, regardless of its position in the sequence, unless bitten by the mouse. Mice which bit the cobra were usually released. Cobra struck mice died more quickly if held in the jaws and the range of death rates was less than for mice released.
45 citations
TL;DR: That all three polypeptides are integral parts of CVF was demonstrated by investigation of the chain pattern after partial reduction, which showed that CVFh is much more sensitive to tryptic attack than CVFn.
Abstract: The chain structure of cobra venom factor, whether isolated from Naja naja venom (CVFn) or from Naja haje venom (CVFh), is similar. Both homologous proteins are composed of three disulphide-linked chains (A, B, and C) with apparent molecular weights of 72,000, 54,000, and 27,000–35,000 for CVFn and 68,000, 51,000, and 30,000–32,000 for CVFh. That all three polypeptides are integral parts of CVF was demonstrated by investigation of the chain pattern after partial reduction. Reduction with 1–2 mM dithiothreitol under nondenaturing conditions yielded free B-chain, together with an intermediate product composed of disulphide-linked A- and C-chains. The C-chain was heterogenous when investigated by electrophoresis in polyacrylamide slab gels in the presence of SDS. Similarly, isoelectric focusing of CVFn and CVFh showed a multiplicity of bands in the pH range 5.2–6.4. Limited tryptic digestion resulted primarily in the fragmentation of the B-chain. CVFh is much more sensitive to tryptic attack than CVFn. In all our preparations of CVFh a partial, trypsin-like fragmentation of the B-chain was detectable to various extents.
22 citations
Journal Article•
5 citations