Contryphans from Conus textile venom ducts.
Contryphans are unusual Conus peptides which contain a distinctive post-translational modification, D-tryptophan or D-leucine. cDNA clones encoding new contryphans from the mollusc-hunting cone snail Conus textile were identified and the inferred mature peptides were synthesized: contryphan-Tx (Gly-Cys-Hyp-D-Trp-Gln-Pro-Tyr-Cys-NH(2)), Leu-contryphan-Tx (Cys-Val-D-Leu-Tyr-Pro-Trp-Cys-NH(2)) and contryphan R/Tx which is identical to contryphan-R [Jimenez et al., 1996. Contryphan is a D-tryptophan containing Conus peptide. J. Biol. Chem. 281, 28002-28005]. Leu-contryphan-Tx exhibits a single peak, but contryphan-Tx shows two peaks under reverse-phase high-performance liquid chromatography conditions. Ultraviolet resonance Raman spectroscopy demonstrates a difference in the D-tryptophan dihedral angle for the two contryphan-Tx equilibrium conformers. Both the sequences and in vivo effects of all contryphans isolated suggest that there are two major branches of the contryphan family.
Jimenez
E C
EC
Department of Biology, University of Utah, Salt Lake City, UT 84112, USA.
Watkins
M
M
Juszczak
L J
LJ
Cruz
L J
LJ
Olivera
B M
BM
D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D018076:DNA, Complementary; D008387:Marine Toxins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D008974:Mollusca; D008978:Mollusk Venoms / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
D018076:DNA, Complementary; D008387:Marine Toxins; D008978:Mollusk Venoms