Xi X , Li B , Chen T , Kwok HF .

	Figure 1. (a) cDNA-encoded biosynthetic precursors are identified from skin secretion of Bombina maxima; (b) cDNA-encoded biosynthetic precursors are identified from skin secretion of Bombina orientalis and Bombina variegate. BOK and BVK represent preprobradykinin kininogens from Bombina orientalis and Bombina variegate, respectively. The putative signal peptide sequences are shown in italic typeface and the mature peptide sequences are represented in bold typeface. The access numbers are shown after the name of each precursor.
	Figure 2. Biosynthetic precursors were identified from skin secretion of the amphibian family, Hylidae. The species and their access numbers are shown before the alignments of each precursor. The classic prepropeptide convertase processing sites –KR– are shown in bold typeface. The putative acidic amino acid residues rich peptides were located between two –KR– in each case. The regions with a single underline indicate highly conserved sequences as compared to conventional BK.
	Figure 3. Biosynthetic skin prepropeptides are identified from skin secretion of multiple species from Ranidae. (a) Three BRP precursors are identified from Lithobates palustris; (b) Four skin prepropeptides are identified from Rana guentheri; (c) Four prepropeptides were discovered from Rana chensinensis; (d) The skin prepropeptides containing single copies were discovered in skin secretion of multiple Ranidae species. The access numbers of the Uniprot database are shown at the head of each precursor. The regions shown in italic typeface are signal peptides. Classic prepropeptide convertase processing sites, –KR–, are shown in bold typeface. The regions with a single underline indicate highly conserved sequences as compared to conventional BK.
	Figure 3. Biosynthetic skin prepropeptides are identified from skin secretion of multiple species from Ranidae. (a) Three BRP precursors are identified from Lithobates palustris; (b) Four skin prepropeptides are identified from Rana guentheri; (c) Four prepropeptides were discovered from Rana chensinensis; (d) The skin prepropeptides containing single copies were discovered in skin secretion of multiple Ranidae species. The access numbers of the Uniprot database are shown at the head of each precursor. The regions shown in italic typeface are signal peptides. Classic prepropeptide convertase processing sites, –KR–, are shown in bold typeface. The regions with a single underline indicate highly conserved sequences as compared to conventional BK.

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