The cDNA sequence coding for prepro-PGS (prepro-magainins) and aspects of the processing of this prepro-polypeptide.
Amphibian skin is well known as a source of peptides homologous to bioactive peptides found in mammalian gut and brain. A systematic investigation of the skin secretions from Xenopus laevis revealed several peptides not derivable from known precursors. The sequence elucidation, utilizing fast atom bombardment/mass spectrometry, of two peptides, PGS and PGS Gly-10;Lys-22, is reported. These have been independently characterized and named magainins and found to have antimicrobial activity. A mixed sequence oligonucleotide probe complementary to the mRNA sequence coding for PGS was synthesized and used to screen a Xenopus skin cDNA library. A full length cDNA species encoding prepro-PGS was isolated and characterized, and its sequence is reported. The deduced precursor sequence was found to contain one copy of PGS Gly-10;Lys-22 and five copies of PGS. The proteolytic processing of this prepro-polypeptide is discussed.
Terry
A S
AS
University Chemical Laboratories, Cambridge, United Kingdom.
Poulter
L
L
Williams
D H
DH
Nutkins
J C
JC
Giovannini
M G
MG
Moore
C H
CH
Gibson
B W
BW
D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000235:genetics*; D004262:DNA Restriction Enzymes; D054806:Magainins; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010455:Peptides / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D012867:Skin / Q000032:analysis*; D029867:Xenopus Proteins; D014982:Xenopus laevis
D023181:Antimicrobial Cationic Peptides; D054806:Magainins; D010455:Peptides; D011498:Protein Precursors; D012333:RNA, Messenger; D029867:Xenopus Proteins; C053301:magainin 2 peptide, Xenopus; C053300:magainin 1 peptide, Xenopus; D004247:DNA; D004262:DNA Restriction Enzymes