Project description:Iron is limiting in the environment, bacteria respond to this deprivation by activating genes required for bacterial iron homeostasis. Transcriptional regulation in response to iron in Gram-negative bacteria is largely mediated by the ferric uptake regulator protein Fur, which in the presence of iron binds to a specific sequence in the promoter regions of genes under its control and acts as a repressor. Here we describe comparative global gene expression analysis using DNA microarray based on the whole genome sequence of the magnetotactic bacterium Magnetospirillum magneticum AMB-1 was conducted between wild type strain and a non-magnetic NMA61 mutant strain, generated by mini-Tn5 transposon mutagenesis which is incapable of assimilating iron to cytoplasm. No induction of the fur genes in NMA61 mutant strain was considered to be due to low intracellular iron concentration. In the iron-replete condition, among 4492 genes, 434 genes were down-regulated and 527 genes were up-regulated in the wild type strain. Among 434 genes down-regulated, 299 genes were not down-regulated in NMA61 mutant strain, indicating these genes are candidates of Fur-regulated. A non-magnetic mutant of Magnetospirillum magneticum AMB-1 (NMA61) generated transposon mutagenesis was grown under various iron conditions. Global gene expression analysis of iron-inducible genes was conducted by using DNA microarray.
Project description:Deatails of the series are available in the publications Suzuki et al., The Journal of Bacteriology “Global gene expression analysis of iron-inducible genes in Magnetospirillum magneticum AMB-1”, accepted for the publication. The gene expression profiles were categorized into 5 patterns. Abstract of the publication: "feo, tpd and ftr which encode ferrous transporters were up-regulated under iron-rich conditions.The concomitant rapid iron uptake and magnetite formation suggest that these uptake systems serve as iron supply lines for magnetosome synthesis." Keywords: iron response
Project description:Iron is limiting in the environment, bacteria respond to this deprivation by activating genes required for bacterial iron homeostasis. Transcriptional regulation in response to iron in Gram-negative bacteria is largely mediated by the ferric uptake regulator protein Fur, which in the presence of iron binds to a specific sequence in the promoter regions of genes under its control and acts as a repressor. Here we describe comparative global gene expression analysis using DNA microarray based on the whole genome sequence of the magnetotactic bacterium Magnetospirillum magneticum AMB-1 was conducted between wild type strain and a non-magnetic NMA61 mutant strain, generated by mini-Tn5 transposon mutagenesis which is incapable of assimilating iron to cytoplasm. No induction of the fur genes in NMA61 mutant strain was considered to be due to low intracellular iron concentration. In the iron-replete condition, among 4492 genes, 434 genes were down-regulated and 527 genes were up-regulated in the wild type strain. Among 434 genes down-regulated, 299 genes were not down-regulated in NMA61 mutant strain, indicating these genes are candidates of Fur-regulated. Keywords: Iron, magnetotactic bacteria
Project description:Expression analysis of Magnetospirillum magneticum AMB-1 WT, ΔMAI, ΔctrA, ΔdivK, and ΔctrA complemented with CtrA D51E, CtrA D51A, and an empty vector control