title: Identification, eukaryotic expression and structure & function characterizations of β-defensin like homologues from Pelodiscus sinensis.
abstract: Defensins are a group of host defense peptides that play a central role in host innate immune responses. Here, 26 genes encoding β-defensin-like peptides have been identified for the first time in Pelodiscus sinensis using database mining approach. Phylogenetic study confirmed that β-defensins are fast evolving genes with high rates of sequence substitutions. The expression level of several selected genes in different tissues was examined by RT-PCR. Ps-BDs mainly adopt β-strands and/or α-helix conformations homology modeled by Rosetta program. Further, Ps-BD2 was expressed in Pichia pastoris and purified using Ni-NTA column and RT-HPLC. As expected, the rPs-BD2 showed strong antimicrobial activity, but displayed a negligible hemolytic and cytotoxic activity on human erythrocytes and Raw 264.7 murine macrophage cells, respectively. Our results suggested that the Ps-BD2 was produced efficiently in P. pastoris expression system, which makes the large-scale use of rPs-BDs possible in the future clinical practice.
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China. Electronic address: yuhaining@dlut.edu.cn.
authors.forename: Haining
authors.initials: H
authors.lastname: Yu
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China.
authors.forename: Xuelian
authors.initials: X
authors.lastname: Liu
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Feng
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Qiao
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China.
authors.forename: Shasha
authors.initials: S
authors.lastname: Cai
authors.affiliation: School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China.
authors.forename: Nannan
authors.initials: N
authors.lastname: Shi
authors.affiliation: College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123 China. Electronic address: yipengwang@suda.edu.cn.
authors.forename: Yipeng
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism*; D003001:Cloning, Molecular; D003198:Computer Simulation; D020869:Gene Expression Profiling; D007113:Immunity, Innate; D010802:Phylogeny; D011487:Protein Conformation; D015202:Protein Engineering; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D014426:Turtles / Q000276:immunology*; D023083:beta-Defensins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D023083:beta-Defensins
keywords: Eukaryotic expression; Pelodiscus sinensis; Phylogenetic analysis; Tertiary structure; β-Defensin