title: Photo-biological hydrogen production by an acid tolerant mutant of Rhodovulum sulfidophilum P5 generated by transposon mutagenesis.
abstract: Most of the photosynthetic bacterial strains exhibit optimum hydrogen production at neutral initial pH, and lower initial pH resulted in a sharp decrease in hydrogen yield. Thus, screening of acid-tolerant hydrogen-producing photosynthetic bacteria is very important. To obtain acid tolerant mutants, a Tn7-based transposon was randomly inserted into the genomic DNA of Rhodovulum sulfidophilum P5. An acid tolerant mutant strain TH-102 exhibited increased hydrogen production in acidic environment (pH 4.5-6.5) and at higher temperatures (35 and 37°C) than the wild-type strain. At pH 5.5 and 35°C, the mutant strain TH-102 continuously produced hydrogen. The hydrogen yield and average rate were 2.16 ± 0.10 mol/mol acetate and 10.06 ± 0.47 mL/Lh, which was about 17.32 and 15.37-fold higher than that of the wild-type strain, respectively. This acid- and temperature-tolerant mutant strain TH-102 could be used in a cost-effective hydrogen production process employing both dark fermentative and photosynthetic bacteria.
authors.affiliation: Tianjin Key Laboratory of Marine Resources and Chemistry, College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, PR China. Electronic address: jinlingcai@tust.edu.cn.
authors.forename: Jinling
authors.initials: J
authors.lastname: Cai
authors.affiliation: Tianjin Key Laboratory of Marine Resources and Chemistry, College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, PR China; Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, Shandong, PR China. Electronic address: gcwang@ms.qdio.ac.cn.
authors.forename: Guangce
authors.initials: G
authors.lastname: Wang
mesh_terms: D000143:Acids / Q000494:pharmacology*; D000222:Adaptation, Physiological / Q000187:drug effects*; D061249:Batch Cell Culture Techniques; D004251:DNA Transposable Elements / Q000235:genetics*; D006859:Hydrogen / Q000378:metabolism*; D016296:Mutagenesis / Q000187:drug effects / Q000235:genetics; D009154:Mutation / Q000235:genetics*; D018462:Photobiology / Q000379:methods*; D016133:Polymerase Chain Reaction; D041903:Rhodovulum / Q000187:drug effects / Q000235:genetics*; D013696:Temperature
chemical_list: D000143:Acids; D004251:DNA Transposable Elements; D006859:Hydrogen
keywords: Acid tolerant; Hydrogen production; Mutation; Photosynthetic bacteria; Transposon