A protein with antimicrobial activity in the skin of Schlegel's green tree frog Rhacophorus schlegelii (Rhacophoridae) identified as histone H2B.
An extract of the skin of Schlegel's green tree frog, Rhacophorus schlegelii (Anura: Rhacophoridae), contained a protein that inhibited the growth of the Gram-negative bacterium Escherichia coli but was inactive against the Gram-positive bacterium Staphylococcus aureus. The protein was purified to near homogeneity by reverse-phase HPLC and amino acid sequence analysis of the products of an endoproteinase Glu-C digest identified the protein as histone H2B. The complete primary structure of the 125 amino acid residue Rhacophorus histone H2B was determined by nucleotide sequence analysis of a cloned cDNA encoding the protein. Mass spectrometry demonstrated that the protein isolated from the skin was not post-translationally modified. Histone fragments with antimicrobial activity were not identified in the Rhacophorus skin extract nor were cationic, alpha-helical antimicrobial peptides of the kind isolated from the skins of several other frog families. The data provide further evidence that histones play a role in the defense against microorganisms.
Kawasaki
Hiroaki
H
Department of Biology, Faculty of Science, Toho University, Funabashi, 274-8510, Chiba, Japan.
Isaacson
Todd
T
Iwamuro
Shawichi
S
Conlon
J Michael
JM
D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents; D001001:Anura / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D004926:Escherichia coli / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D006657:Histones / Q000737:chemistry* / Q000145:classification / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D017385:Sequence Homology; D012867:Skin / Q000737:chemistry* / Q000378:metabolism; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D006657:Histones