title: Improvement of surfactin production in Bacillus subtilis using synthetic wastewater by overexpression of specific extracellular signaling peptides, comX and phrC.
abstract: Surfactin is a biological surfactant with numerous potential applications. In this study, Bacillus subtilis was engineered to improve surfactin production by the activation of two competence-stimulating pheromones, ComX and competence and sporulation factor (CSF) to stimulate the transcription of srfA operon. Both signaling factors, encoded by comX and phrC, were successfully overexpressed and subsequently increased surfactin production. Surfactin produced by engineered strains showed functional groups similar to the commercially available surfactin analyzed via Fourier transform infrared spectroscopy (FTIR). Surfactin production in the B. subtilis (pHT43-comXphrC) strain was 6.4-fold greater than in the wild strain, with approximately 135.1 mg/L surfactin produced after 48 h cultivation. To reduce the production costs of surfactin, synthetic wastewater was used, from which the B. subtilis (pHT43-comXphrC) strain produced approximately 140.2 mg/L surfactin. The results obtained demonstrated the production of surfactin from synthetic wastewater, which is beneficial in lowering the overall production costs.
authors.affiliation: School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Ju
authors.initials: J
authors.lastname: Jung
authors.forename: Kyung Ok
authors.initials: KO
authors.lastname: Yu
authors.forename: Ahmad Bazli
authors.initials: AB
authors.lastname: Ramzi
authors.forename: Se Hoon
authors.initials: SH
authors.lastname: Choe
authors.forename: Seung Wook
authors.initials: SW
authors.lastname: Kim
authors.forename: Sung Ok
authors.initials: SO
authors.lastname: Han
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005818:Genetic Engineering; D055666:Lipopeptides / Q000096:biosynthesis* / Q000191:economics / Q000378:metabolism; D008956:Models, Chemical; D010456:Peptides, Cyclic / Q000096:biosynthesis* / Q000191:economics / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D012097:Repressor Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D012722:Sewage; D014867:Water / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C087040:ComX protein, Bacillus subtilis; D055666:Lipopeptides; D010456:Peptides, Cyclic; C101115:PhrC protein, Bacillus subtilis; D012097:Repressor Proteins; D012722:Sewage; D014867:Water; C009365:surfactin peptide