title: Effects of different replicons in conjugative plasmids on transformation efficiency, plasmid stability, gene expression and n-butanol biosynthesis in Clostridium tyrobutyricum.
abstract: Clostridium tyrobutyricum ATCC 25755 can produce butyric acid, acetic acid, and hydrogen as the main products from various carbon sources. In this study, C. tyrobutyricum was used as a host to produce n-butanol by expressing adhE2 gene under the control of a native thiolase promoter using four different conjugative plasmids (pMTL82151, 83151, 84151, and 85151) each with a different replicon (pBP1 from C. botulinum NCTC2916, pCB102 from C. butyricum, pCD6 from Clostridium difficile, and pIM13 from Bacillus subtilis). The effects of different replicons on transformation efficiency, plasmid stability, adhE2 expression and aldehyde/alcohol dehydrogenase activities, and butanol production by different mutants of C. tyrobutyricum were investigated. Among the four plasmids and replicons studied, pMTL82151 with pBP1 gave the highest transformation efficiency, plasmid stability, gene expression, and butanol biosynthesis. Butanol production from various substrates, including glucose, xylose, mannose, and mannitol were then investigated with the best mutant strain harboring adhE2 in pMTL82151. A high butanol titer of 20.5 g/L with 0.33 g/g yield and 0.32 g/L h productivity was obtained with mannitol as the substrate in batch fermentation with pH controlled at ~6.0.
authors.affiliation: William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, 140 West 19th Ave., Columbus, OH 43210, USA.
authors.forename: Mingrui
authors.initials: M
authors.lastname: Yu
authors.forename: Yinming
authors.initials: Y
authors.lastname: Du
authors.forename: Wenyan
authors.initials: W
authors.lastname: Jiang
authors.forename: Wei-Lun
authors.initials: WL
authors.lastname: Chang
authors.forename: Shang-Tian
authors.initials: ST
authors.lastname: Yang
authors.forename: I-Ching
authors.initials: IC
authors.lastname: Tang
mesh_terms: D020001:1-Butanol / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D053898:Biosynthetic Pathways / Q000235:genetics*; D050260:Carbohydrate Metabolism; D048014:Clostridium tyrobutyricum / Q000235:genetics / Q000378:metabolism*; D003227:Conjugation, Genetic; D015870:Gene Expression; D042822:Genomic Instability; D060847:Metabolic Engineering; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012093:Replicon; D014169:Transformation, Bacterial
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D020001:1-Butanol; C446050:AdhE2 protein, Clostridium acetobutylicum; D010088:Oxidoreductases