title: A mutation upstream of an ATPase gene significantly increases magnetosome production in Magnetospirillum gryphiswaldense.
abstract: A mutant of Magnetospirillum gryphiswaldense, NPHB, was obtained from a conjugation experiment. An aberrant recombination occurred between a putative elongation factor-G gene (fus-like) of the bacterial chromosome and the chloramphenicol resistant gene (cat) of a suicide vector, pSUP202. Complementary experiments and transcription analysis of genes around the recombinant site showed that the cat promoter enhanced the expression of adenosine triphosphatase gene downstream. Adenosine triphosphate hydrolyzing activity in NPHB was 35% higher than in the wild-type strain (M. gryphiswaldense MSR-1). NPHB accumulated 71% less poly-beta-hydroxybutyrate and consumed 56% more oxygen and 40% more lactate than MSR-1. The magnetosome content of NPHB was 69% higher than MSR-1 in flask culture. NPHB cultured in a 7.5-L bioreactor gave a maximum yield of 58.4 +/- 6.4 mg magnetosomes per liter.
authors.affiliation: State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Jiangning
authors.initials: J
authors.lastname: Liu
authors.forename: Yao
authors.initials: Y
authors.lastname: Ding
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.forename: Jiesheng
authors.initials: J
authors.lastname: Tian
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Jilun
authors.initials: J
authors.lastname: Li
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D005290:Ferric Compounds / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D007501:Iron / Q000378:metabolism; D008280:Magnetics; D042201:Magnetospirillum / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D011995:Recombination, Genetic; D013440:Sulfides / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D005290:Ferric Compounds; D013440:Sulfides; C111959:greigite; C000499:ferric oxide; D007501:Iron; D000251:Adenosine Triphosphatases