title: Characterization and functional study of a Cecropin-like peptide from the Chinese oak silkworm, Antheraea pernyi.
abstract: In present study, a Cecropin-like peptide from Antheraea pernyi (ApCec) was cloned and characterized. The full-length ApCec cDNA encoded a protein with 64 amino acids including a putative 22-amino-acid signal peptide, a 4-amino-acid propeptide, and a 38-amino-acid mature peptide. ApCec gene was highly expressed in Malpighian tubules of A. pernyi after induction for 24 h by Escherichia coli in PBS. Pro-ApCec (including propeptide and mature peptide) and M-ApCec (just mature peptide) were synthesized chemically and analyzed by HPLC and mass spectroscopy. The antibacterial activity of M-ApCec is more potent than pro-ApCec against E. coli K12 or B. subtilus in both minimum inhibitory concentration and inhibition zone assays. Hemolytic assay results showed M-ApCec possessed a low cytotoxicity to mammalian cells. The secondary structure of M-ApCec forms α-helical structure, shown by circular dichroism spectroscopy. Transmission electron microscopy analysis suggested that M-ApCec killed bacteria by disrupting bacterial cell membrane integrity. Our results indicate ApCec may play an important role in defending from pathogenic bacteria in A. pernyi, and it may be as a potential candidate for applications in antibacterial drug development and agriculture.
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.|State Key Laboratory of Rice Biology, Institute of Insect Sciences, Zhejiang University, Hangzhou, Zhejiang, China.|Key Laboratory of Agricultural Entomology of Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Shao-Liang
authors.initials: SL
authors.lastname: Fang
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Insect Sciences, Zhejiang University, Hangzhou, Zhejiang, China.|Key Laboratory of Agricultural Entomology of Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Fang
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Xiao-San
authors.initials: XS
authors.lastname: Zhao
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Cen
authors.initials: C
authors.lastname: Qian
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Wei
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Bao-Jian
authors.initials: BJ
authors.lastname: Zhu
authors.affiliation: College of Life Science, Anhui Agricultural University, Hefei, Anhui, China.
authors.forename: Chao-Liang
authors.initials: CL
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D054807:Cecropins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000502:physiology; D048168:Escherichia coli K12 / Q000187:drug effects; D005786:Gene Expression Regulation; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D009036:Moths / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D000900:Anti-Bacterial Agents; D054807:Cecropins; D018076:DNA, Complementary; D019476:Insect Proteins; D012333:RNA, Messenger
keywords: Antheraea pernyi; antibacterial activity; antibacterial peptide; cecropin