1. Antibacterial and haemolytic peptides containing D-alloisoleucine from the skin of Bombina variegata
G Mignogna, M Simmaco, G Kreil, D Barra EMBO J. 1993 Dec;12(12):4829-32. doi: 10.1002/j.1460-2075.1993.tb06172.x.
A family of bombinin-related peptides is present in the skin of Bombina variegata. These peptides contain 27 residues with Gly as N-terminus and display antimicrobial activity. From sequence analysis of the cDNAs encoding for the corresponding peptide precursors, the presence of a novel 20-residue peptide with Ile as N-terminus was predicted. We have now purified a family of hydrophobic peptides named H1-H5, whose sequences correspond to the predicted peptide with some variability in positions 1, 2 and 8. In particular, H3-H5 contain a D-alloisoleucine residue in the second position. All these peptides display antibacterial and haemolytic activity.
2. Antimicrobial peptides from skin secretions of Chinese red belly toad Bombina maxima
Ren Lai, Yong Tang Zheng, Ji Hong Shen, Guan Jie Liu, Hen Liu, Wen Hui Lee, Shao Zhong Tang, Yun Zhang Peptides. 2002 Mar;23(3):427-35. doi: 10.1016/s0196-9781(01)00641-6.
Two groups of antimicrobial peptides have been isolated from skin secretions of Bombina maxima. Peptides in the first group, named maximins 1, 2, 3, 4 and 5, are structurally related to bombinin-like peptides (BLPs). Unlike BLPs, sequence variations in maximins occurred all through the molecules. In addition to the potent antimicrobial activity, cytotoxicity against tumor cells and spermicidal action of maximins, maximin 3 possessed a significant anti-HIV activity. Maximins 1 and 3 were toxic to mice with LD(50) values of 8.2 and 4.3 mg/kg, respectively. Peptides in the second group, termed maximins H1, H2, H3 and H4, are homologous with bombinin H peptides. cDNA sequences revealed that one maximin peptide plus one maximin H peptide derived from a common larger protein.
