title: The Disruption of an OxyR-Like Protein Impairs Intracellular Magnetite Biomineralization inMagnetospirillum gryphiswaldenseMSR-1.
abstract: Magnetotactic bacteria synthesize intracellular membrane-enveloped magnetite bodies known as magnetosomes which have been applied in biotechnology and medicine. A series of proteins involved in ferric ion transport and redox required for magnetite formation have been identified but the knowledge of magnetosome biomineralization remains very limited. Here, we identify a novel OxyR homolog (named OxyR-Like), the disruption of which resulted in low ferromagnetism and disfigured nano-sized iron oxide crystals. High resolution-transmission electron microscopy showed that these nanoparticles are mainly composed of magnetite accompanied with ferric oxide including α-Fe2O3and 𝜀-Fe2O3. Electrophoretic mobility shift assay and DNase I footprinting showed that OxyR-Like binds the conserved 5'-GATA-N{9}-TATC-3' region within the promoter of pyruvate dehydrogenase (pdh) complex operon. Quantitative real-time reverse transcriptase PCR indicated that not only the expression ofpdhoperon but also genes related to magnetosomes biosynthesis and tricarboxylic acid cycle decreased dramatically, suggesting a link between carbon metabolism and magnetosome formation. Taken together, our results show that OxyR-Like plays a key role in magnetosomes formation.
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Tong
authors.initials: T
authors.lastname: Wen
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry SciencesBeijing, China.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Geng
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Junquan
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University Beijing, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Guohua
authors.initials: G
authors.lastname: Guan
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Jiesheng
authors.initials: J
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Jilun
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Chemistry and Molecular Engineering, Peking University Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ju
authors.affiliation: State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural UniversityBeijing, China; France-China Bio-Mineralization and Nano-Structures LaboratoryBeijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
keywords: Magnetospirillum gryphiswaldense MSR-1; OxyR-like protein; biomineralization; carbon metabolism; magnetosome formation