title: A plate method for rapid screening of Ketogulonicigenium vulgare mutants for enhanced 2-keto-l-gulonic acid production.
abstract: A new plate method was developed for rapid screening of Ketogulonicigenium vulgare mutants overproducing 2-keto-l-gulonic acid (2-KLG). The screening methodology took the advantage of the acidity caused by 2-KLG, which changes the color of bromothymol blue (pH indicator) from blue to yellow. Using the proposed method, a mutant, K. vulgare 65, was selected from 20,000 colonies produced by a strain subjected to spaceflight mutagenesis. When co-cultured with Bacillus megaterium 2980 in 20-L fermenters, K. vulgare 65 showed a high conversion rate (94.45%) of l-sorbose to 2-KLG. In contrast to the traditional screening method, this one significantly improved the frequency of obtaining positive mutants. The proposed plate screening method is cost-effective and easy to run and is thus useful for the isolation and screening of K. vulgare mutants overproducing 2-KLG.
authors.affiliation: Chinese Academy of Sciences, Institute of Applied Ecology, Shenyang, China.
authors.forename: Weichao
authors.initials: W
authors.lastname: Yang
authors.affiliation: Northeast Pharmaceutical Group Co., Ltd., Fermentation & Biotechnology Laboratory, Shenyang, China.
authors.forename: Litao
authors.initials: L
authors.lastname: Han
authors.affiliation: Chinese Academy of Sciences, Institute of Applied Ecology, Shenyang, China.
authors.forename: Mandlaa
authors.initials: M
authors.lastname: Mandlaa
authors.affiliation: Northeast Pharmaceutical Group Co., Ltd., Fermentation & Biotechnology Laboratory, Shenyang, China.
authors.forename: Haihong
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Chinese Academy of Sciences, Institute of Applied Ecology, Shenyang, China.
authors.forename: Zhongze
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Chinese Academy of Sciences, Institute of Applied Ecology, Shenyang, China. Electronic address: hui.xu67@gmail.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
mesh_terms: D001431:Bacteriological Techniques / Q000295:instrumentation / Q000379:methods*; D005285:Fermentation; D009154:Mutation; D041902:Rhodobacteraceae / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D013013:Sorbose / Q000378:metabolism; D013400:Sugar Acids / Q000378:metabolism*
chemical_list: D013400:Sugar Acids; C011491:provitamin C; D013013:Sorbose
keywords: 2-Keto-l-gulonic acid; Ketogulonicigenium vulgare; Rapid screening; Spaceflight mutation; pH indicator