title: Secretory expression of lacticin Q fused with SUMO in Bacillus subtilis.
abstract: Lacticin Q is a 53-amino acid Class II bacteriocin produced by Lactococcus lactis QU 5. It shows antibacterial activity comparable to that of nisin A in terms of both spectrum and intensity. Moreover, it remains stable at alkaline pH values, while nisin A was inactivated. It may possibly be employed as an alternative to or in combination with nisin A. The objective of this study was to express lacticin Q extracellularly with Small ubiquitin-related modifier (SUMO) fusion technology in Bacillus subtilis. Secretory SUMO-lacticin Q fusion protein was efficiently produced in B. subtilis WB600 transformed with the recombinant expression plasmid and accounted for 19% of the culture supernatant proteins. Fusion SUMO-lacticin Q was purified by nickel nitrilotriacetate (Ni-NTA) affinity chromatography and digested with SUMO protease to release lacticin Q. Lacticin Q was further purified by Ni-NTA chromatography to yield about 2.5 mg of lacticin Q with more than 93% purity from 1L of supernatant of fermentation culture. An activity assay indicated that the recombinant bacteriocin exhibited excellent antimicrobial activity against indicator strains. The results obtained suggest that the secretory lacticin Q was efficiently expressed using SUMO fusion technology in B. subtilis. The expression and purification system could promote the application of lacticin Q in food and medicine.
authors.affiliation: Laboratory of Feed Biotechnology, State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
authors.forename: Zhanqiao
authors.initials: Z
authors.lastname: Yu
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.forename: Qingshan
authors.initials: Q
authors.lastname: Ma
authors.forename: Rijun
authors.initials: R
authors.lastname: Zhang
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism; D001412:Bacillus subtilis / Q000737:chemistry / Q000235:genetics*; D001430:Bacteriocins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli; D015964:Gene Expression Regulation, Bacterial; D013294:Lactococcus lactis / Q000235:genetics / Q000378:metabolism; D009561:Nisin / Q000737:chemistry / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D025842:SUMO-1 Protein / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D025801:Ubiquitin / Q000235:genetics / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D011993:Recombinant Fusion Proteins; D025842:SUMO-1 Protein; D025801:Ubiquitin; C548356:lacticin Q, Lactococcus lactis; D009561:Nisin; C102526:nisin A