Contryphan Genes and Mature Peptides in the Venom of Nine Cone Snail Species by Transcriptomic and Mass Spectrometric Analysis.
The occurrence of contryphans, a class of single-disulfide-bond-containing peptides, is demonstrated by the analysis of the venom of nine species of cone snails. Ten full gene sequences and two partial gene sequences coding for contryphan precursor proteins have been identified by next-generation sequencing and compared with available sequences. The occurrence of mature peptides in isolated venom has been demonstrated by LC-ESI-MS/MS analysis. De novo sequencing of reduced, alkylated contryphans from C. frigidus and C. araneosus provides evidence of sequence variation and post-translational modification, notably gamma carboxylation of glutamic acid. The characterization of Fr965 (C. frigidus) provides a rare example of a sequence lacking Pro at position 5 in the disulfide loop. The widespread occurrence of contryphan genes and mature peptides in the venom of diverse cone snails is suggestive of their potential biological significance.
Molecular Biophysics Unit, Indian Institute of Science , Bangalore 560012, India.
Marimuthu
M
Vijayasarathy
Molecular Biophysics Unit, Indian Institute of Science , Bangalore 560012, India.
Soorej M
SM
Basheer
Andaman and Nicobar Centre for Ocean Science and Technology, Earth System Sciences Organisation-National Institute of Ocean Technology, Ministry of Earth Sciences, Government of India , Port Blair 744103, India.
Jayaseelan Benjamin
JB
Franklin
Molecular Biophysics Unit, Indian Institute of Science , Bangalore 560012, India.
Padmanabhan
0000-0002-6577-933X
P
Balaram
D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D020916:Conotoxins / Q000737:chemistry / Q000235:genetics*; D052078:Conus Snail / Q000737:chemistry / Q000235:genetics; D013058:Mass Spectrometry; D010455:Peptides / Q000737:chemistry / Q000235:genetics; D010456:Peptides, Cyclic / Q000235:genetics*; D011499:Protein Processing, Post-Translational; D059467:Transcriptome / Q000235:genetics*; D014688:Venoms / Q000737:chemistry / Q000235:genetics*
D020916:Conotoxins; D010455:Peptides; D010456:Peptides, Cyclic; D014688:Venoms; C102355:contryphan
Conus venom peptides; cone snails; conotoxins; contryphan genes; contryphans; mass spectrometry; next-generation sequencing; peptide disulfides