title: The acquisition of Clostridium tyrobutyricum mutants with improved bioproduction under acidic conditions after two rounds of heavy-ion beam irradiation.
abstract: End-product inhibition is a key factor limiting the production of organic acid during fermentation. Two rounds of heavy-ion beam irradiation may be an inexpensive, indispensable and reliable approach to increase the production of butyric acid during industrial fermentation processes. However, studies of the application of heavy ion radiation for butyric acid fermentation engineering are lacking. In this study, a second (12)C(6+) heavy-ion irradiation-response curve is used to describe the effect of exposure to a given dose of heavy ions on mutant strains of Clostridium tyrobutyricum. Versatile statistical elements are introduced to characterize the mechanism and factors contributing to improved butyric acid production and enhanced acid tolerance in adapted mutant strains harvested from the fermentations. We characterized the physiological properties of the strains over a large pH value gradient, which revealed that the mutant strains obtained after a second round of radiation exposure were most resistant to harsh external pH values and were better able to tolerate external pH values between 4.5 and 5.0. A customized second round of heavy-ion beam irradiation may be invaluable in process engineering.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.|Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.|University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Jiang
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.
authors.forename: Shu-Yang
authors.initials: SY
authors.lastname: Wang
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Liang
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.
authors.forename: Xi-Hong
authors.initials: XH
authors.lastname: Lu
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences,509 Nanchang Rd., Lanzhou, Gansu 730000, P. R. China.|University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
mesh_terms: D018533:Biomass; D001709:Biotechnology / Q000379:methods*; D020148:Butyric Acid / Q000494:pharmacology; D048014:Clostridium tyrobutyricum / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005285:Fermentation / Q000187:drug effects; D020450:Heavy Ions; D006863:Hydrogen-Ion Concentration; D008390:Markov Chains; D009010:Monte Carlo Method; D009154:Mutation / Q000235:genetics*; D025341:Principal Component Analysis; D044967:Serum
chemical_list: D020148:Butyric Acid