title: Mammalian peptide isomerase: platypus-type activity is present in mouse heart.
abstract: Male platypus (Ornithorhynchus anatinus) venom has a peptidyl aminoacyl L/D-isomerase (hereafter called peptide isomerase) that converts the second amino acid residue in from the N-terminus from the L- to the D-form, and vice versa. A reversed-phase high-performance liquid chromatography (RP-HPLC) assay has been developed to monitor the interconversion using synthetic hexapeptides derived from defensin-like peptide-2 (DLP-2) and DLP-4 as substrates. It was hypothesised that animals other than the platypus would have peptide isomerase with the same substrate specificity. Accordingly, eight mouse tissues were tested and heart was shown to have the activity. This is notable for being the first evidence of a peptide isomerase being present in a higher mammal and heralds finding the activity in man.
authors.affiliation: School of Molecular Biosciences, Building G08, University of Sydney, NSW 2006, Australia.
authors.forename: Jennifer M S
authors.initials: JM
authors.lastname: Koh
authors.forename: Stephanie J P
authors.initials: SJ
authors.lastname: Chow
authors.forename: Ben
authors.initials: B
authors.lastname: Crossett
authors.forename: Philip W
authors.initials: PW
authors.lastname: Kuchel
mesh_terms: D000591:Amino Acid Isomerases / Q000378:metabolism*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D008297:Male; D051379:Mice; D009206:Myocardium / Q000201:enzymology*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D010987:Platypus / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D010455:Peptides; D000591:Amino Acid Isomerases