Identification of duck liver-expressed antimicrobial peptide 2 and characterization of its bactericidal activity

Asian-Australasian Journal of Animal Sciences

Hyun S. Lillehoj¹  Geun-Bae Kim²  Kyungbaek Lee²  Anh Duc Truong²  Yeong Ho Hong²  Yeojin Hong²  Janggeun Lee²  Kang-Nyeong Heo³ 

[1] Animal Biosciences and Biotechnology Laboratory, Agricultural Research Services, United States Department of Agriculture, Beltsville, MD 20705, USA;Department of Animal Science and Technology, Chung-Ang University, Anseong 17546, Korea;Poultry Research Institute, National Institute of Animal Science, RDA, Pyeongchang 25342, Korea;

关键词: Antimicrobial Peptides;    Liver-expressed Antimicrobial Peptide 2 (LEAP-2);    Duck;    Disulfide Bond;    Pathogens;   

DOI  :  10.5713/ajas.18.0571

来源: DOAJ

【 摘 要 】

Objective This study was conducted to identify duck liver-expressed antimicrobial peptide 2 (LEAP-2) and demonstrate its antimicrobial activity against various pathogens. Methods Tissue samples were collected from 6 to 8-week-old Pekin ducks (Anas platyrhynchos domesticus), total RNA was extracted, and cDNA was synthesized. To confirm the duck LEAP-2 transcript expression levels, quantitative real-time polymerase chain reaction was conducted. Two kinds of peptides (a linear peptide and a disulfide-type peptide) were synthesized to compare the antimicrobial activity. Then, antimicrobial activity assay and fluorescence microscopic analysis were conducted to demonstrate duck LEAP-2 bactericidal activity. Results The duck LEAP-2 peptide sequence showed high identity with those of other avian species (>85%), as well as more than 55% of identity with mammalian sequences. LEAP-2 mRNA was highly expressed in the liver with duodenum next, and then followed by lung, spleen, bursa and jejunum and was the lowest in the muscle. Both of LEAP-2 peptides efficiently killed bacteria, although the disulfide-type LEAP-2 showed more powerful bactericidal activity. Also, gram-positive bacteria was more susceptible to duck LEAP-2 than gram-negative bacteria. Using microscopy, we confirmed that LEAP-2 peptides could kill bacteria by disrupting the bacterial cell envelope. Conclusion Duck LEAP-2 showed its antimicrobial activity against both gram-positive and gram-negative bacteria. Disulfide bonds were important for the powerful killing effect by disrupting the bacterial cell envelope. Therefore, duck LEAP-2 can be used for effective antibiotics alternatives.

【 授权许可】

Unknown