A novel cationic ribonuclease with antimicrobial activity from Rana dybowskii.
A novel ribonuclease (RNase) A superfamily gene (Rdronc) has been cloned from the frog Rana dybowskii. The deduced amino acid sequence shows that it belongs to the ribonuclease A superfamily, with the highest identity, 73%, to Rana pipiens onconase. Adaptive evolution analysis based on maximum likelihood models of codon substitution has been conducted on 10 members of the Rana RNases of subcluster B. Rapid adaptive evolution and multiple positive selection sites have been detected, which indicates that these genes may be evolving under positive selection pressure. Functional assay demonstrates that the recombinant Rdronc protein possesses antimicrobial activity against Gram-negative Escherichia coli and Pseudomonas aeruginosa and weaker antimicrobial activity against Gram-positive Staphylococcus aureus and yeast Candida albicans. Our findings support the hypothesis that ribonuclease A superfamily members may function in host defense of early-diversified vertebrates.
College of Life Science and Technology, Beijing University of Chemical Technology, China. hgtfengyun@buu.edu.cn
Fengyun
F
Tao
Meiyin
M
Fan
Wei
W
Zhao
Qiang
Q
Lin
Runyu
R
Ma
D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D003001:Cloning, Molecular; D057075:Enzyme Assays; D004926:Escherichia coli / Q000187:drug effects; D008969:Molecular Sequence Data; D010802:Phylogeny; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D011898:Ranidae; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D012259:Ribonuclease, Pancreatic / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D016415:Sequence Alignment; D013211:Staphylococcus aureus / Q000187:drug effects
D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D011994:Recombinant Proteins; D012259:Ribonuclease, Pancreatic