1. Novel antimicrobial peptides isolated from the skin secretions of Hainan odorous frog, Odorrana hainanensis
Hui Wang, Zhijun Yu, Yuhong Hu, Fengjiao Li, Limeng Liu, Hongyuan Zheng, Hao Meng, Shujie Yang, Xiaolong Yang, Jingze Liu Peptides. 2012 Jun;35(2):285-90. doi: 10.1016/j.peptides.2012.03.007. Epub 2012 Mar 16.
Long time geographical isolation of Hainan Island from the China continent has resulted in appearance of many novel frog species. As one of them, Hainan odorous frog, Odorrana hainanensis possesses some special antimicrobial peptides distinct from those found in other Odorrana. In this study, three antimicrobial peptides have been purified and characterized from the skin secretion of O. hainanensis. With the similarity to the temporin family, two peptides are characterized by amidated C-terminals, so they are named as temporin-HN1 (AILTTLANWARKFL-NH(2)) and temporin-HN2 (NILNTIINLAKKIL-NH(2)). The third antimicrobial peptide belongs to the brevinin-1 family which is widely distributed in Eurasian ranids, and thus, it is named as brevinin-1HN1 (FLPLIASLAANFVPKIFCKITKKC). Furthermore, after sequencing 68 clones, eight cDNAs encoding antimicrobial peptide precursors were cloned from the skin-derived cDNA library of O. hainanensis. These eight cDNAs can encode seven mature antimicrobial peptides including the above three, as well as brevinin-1V, brevinin-2HS2, odorranain-A6, and odorranain-B1. Twelve different species of microorganisms were chosen, including Gram-positive, Gram-negative and fungi, to test the antimicrobial activities of temporin-HN1, temporin-HN2, brevinin-1HN1, brevinin-1V, and brevinin-2HS2. The result shows that, in addition to their activities against Gram-positive bacteria, temporin-HN1 and temporin-HN2 also possess activities against some Gram-negative bacteria and fungi. However, the two antimicrobial peptides, brevinin-1HN1 and brevinin-1V of the brevinin-1 family have stronger antimicrobial activities than temporin-HN1 and temporin-HN2 of the temporin family. Brevinin-1HN1 possesses activity against Staphylococcus aureus (ATCC25923), Rhodococcus rhodochrous X15, and Slime mould 090223 at the concentration of 1.2 μM.
2. Host defense peptides from Lithobates forreri, Hylarana luctuosa, and Hylarana signata (Ranidae): phylogenetic relationships inferred from primary structures of ranatuerin-2 and brevinin-2 peptides
J Michael Conlon, et al. Comp Biochem Physiol Part D Genomics Proteomics. 2014 Mar;9:49-57. doi: 10.1016/j.cbd.2014.01.002. Epub 2014 Jan 11.
The primary structures of host-defense peptides present in frog skin secretions constitute useful molecular markers for establishing taxonomic classifications and investigating phylogenetic relationships between species within a particular genus. Peptidomic analysis has led to the characterization of multiple host-defense peptides in norepinephrine-stimulated skin secretions of three species of frogs from the family Ranidae: Lithobates forreri (Boulenger, 1883), Hylarana luctuosa (Peters, 1871), and Hylarana signata (Günther, 1872). The L. forreri secretions contain ranatuerin-2 (2 peptides), brevinin-1 (4 peptides), and temporin (1 peptide). The H. luctuosa secretions contain brevinin-2 (4 peptides), esculentin-1 (1 peptide), esculentin-2 (1 peptide), palustrin-2 (2 peptides), and temporin (2 peptides). The H. signata secretions contain brevinin-2 (4 peptides), brevinin-1 (5 peptides), palustrin-2 (1 peptide), and temporin (2 peptides). Cladistic analysis based upon the primary structures of 44 ranatuerin-2 peptides from 20 Lithobates species indicates a close phylogenetic relationship between L. forreri, Lithobates onca, and Lithobates yavapaiensis. A similar cladistic analysis based upon the primary structures of 27 brevinin-2 peptides from 8 Hylarana species provides support for a close phylogenetic relationship between H. signata and Hylarana picturata, while showing that the species are not conspecific, with H. luctuosa more distantly related.
3. The novel antimicrobial peptides from skin of Chinese broad-folded frog, Hylarana latouchii (Anura:Ranidae)
Hui Wang, Yi Lu, Xiuqing Zhang, Yuhong Hu, Haining Yu, Jingze Liu, Junshe Sun Peptides. 2009 Feb;30(2):273-82. doi: 10.1016/j.peptides.2008.10.016. Epub 2008 Nov 5.
Broad-folded frogs (Hylarana latouchii), one member of 12 species of the genus Hylarana in the Chinese frog fauna, are widely distributed in the South of China. In this study, we purified and characterized three antimicrobial peptides from the skin secretion of H. latouchii. Five different cDNA fragments encoding the precursors of these antimicrobial peptides were cloned, and five mature antimicrobial peptides belonging to two different families were deduced from the five cDNAs. Structural characterization of the mature peptides had identified them as members of the brevinin-1 and temporin families. They were named brevinin-1LTa (FFGTALKIAANVLPTAICKILKKC), brevinin-1LTb (FFGTALKIAANILPTAICKILKKC), temporin-LTa (FFPLVLGALGSILPKIF-NH(2)), temporin-LTb (FIITGLVRGLTKLF-NH(2)) and temorin-LTc (SLSRFLSFLKIVYPPAF-NH(2)). Brevinin-1LTa, temporin-LTa, temporin-LTb and temporin-LTc with different antimicrobial activities induced significant morphological alterations of the tested microbial surfaces as shown by scanning electron microscopy, which indicated strong membrane disruption.
