title: Expression of a Tandemly Arrayed Plectasin Gene from Pseudoplectania nigrella in Pichia pastoris and its Antimicrobial Activity.
abstract: In recent years, various naturally occurring defence peptides such as plectasin have attracted considerable research interest because they could serve as alternatives to antibiotics. However, the production of plectasin from natural microorganisms is still not commercially feasible because of its low expression levels and weak stability. A tandemly arrayed plectasin gene (1,002 bp) from Pseudoplectania nigrella was generated using the isoschizomer construction method, and was inserted into the pPICZαA vector and expressed in Pichia pastoris. The selected P. pastoris strain yielded 143 μg/ml recombinant plectasin (Ple) under the control of the methanol-inducible alcohol oxidase 1 (AOX1) promoter. Ple was estimated by SDS-PAGE to be 41 kDa. In vitro studies have shown that Ple efficiently inhibited the growth of several gram-positive bacteria such as Streptococcus suis and Staphylococcus aureus. S. suis is the most sensitive bacterial species to Ple, with a minimum inhibitory concentration (MIC) of 4 μg/ml. Importantly, Ple exhibited resistance to pepsin but it was quite sensitive to trypsin and maintained antimicrobial activity over a wide pH range (pH 2.0 to 10.0). P. pastoris offers an attractive system for the cost-effective production of Ple. The antimicrobial activity of Ple suggested that it could be a potential alternative to antibiotics against S. suis and S. aureus infections.
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Jin
authors.initials: J
authors.lastname: Wan
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Daiwen
authors.initials: D
authors.lastname: Chen
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Yu
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Ping
authors.initials: P
authors.lastname: Zheng
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Xiangbing
authors.initials: X
authors.lastname: Mao
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yu
authors.affiliation: Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, Sichuan 625014, P.R. China.|Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Beijing 100029, P.R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: He
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism / Q000494:pharmacology*; D015870:Gene Expression; D006094:Gram-Positive Bacteria / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D010455:Peptides / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology*; D010843:Pichia / Q000235:genetics* / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects; D017011:Streptococcus suis / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; C504857:plectasin
keywords: Antimicrobial activity; Expression; Pichia pastoris; Plectasin; Purification