Cloning of the (Thr6)-phyllokinin precursor from Phyllomedusa sauvagei skin confirms a non-consensus tyrosine O-sulfation motif.
Nine bradykinin-related peptides were identified in Phyllomedusa sauvagei skin secretion using QTOF MS/MS fragmentation sequencing. The major peptides were (Thr6)-bradykinin, (Hyp3, Thr6)-bradykinin, (Thr6)-phyllokinin and (Hyp3, Thr6)-phyllokinin. The phyllokinins occurred in both sulfated and non-sulfated forms. All (Thr6)-substituted bradykinins/phyllokinins could be generated from a common precursor by differential post-translational processing and modification. The open-reading frame of the cloned precursor cDNA consisted of 62 amino acid residues with a single bradykinin/phyllokinin coding sequence located at the C-terminus. Structural features included a Glu-Arg processing site at the N-terminus of the bradykinin/phyllokinin domain and the absence of an acidic amino acid residue adjacent to the C-terminal Tyr residue in the phyllokinins. However, the neutral amino acid residue (Ile) at position -1 and the basic amino acid residue (Arg) at position -2 from the Tyr residue, constitute a sulfation motif previously identified only in a protochordean.
Chen
Tianbao
T
Pharmaceutical Biotechnology Research Group, School of Biomedical Sciences, University of Ulster, Cromore Road, BT52 1SA, Northern Ireland, Coleraine, UK.
Shaw
Chris
C
D000595:Amino Acid Sequence; D000818:Animals; D001001:Anura / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D001920:Bradykinin / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D018076:DNA, Complementary; D015723:Gene Library; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D012867:Skin / Q000378:metabolism; D014443:Tyrosine / Q000235:genetics / Q000378:metabolism*
D018076:DNA, Complementary; D010455:Peptides; D014443:Tyrosine; D001920:Bradykinin