Herbaspirillum seropedicae Z67 is a nitrogen-fixing bacterium able to colonize the rhizosphere and the interior of several plants. As iron is a key element for nitrogen fixation, we examined the response of this microorganism to iron deficiency under nitrogen fixing conditions. We identified a H. seropedicae exbD gene that was induced in response to iron limitation and is involved in iron homeostasis. We found that an exbD mutant grown in iron-chelated medium is unable to fix nitrogen. Moreover, we provide evidence that expression of the nifH and nifA genes is iron dependent in a H. seropedicae genetic background.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1574-6968.2006.00218.x | DOI Listing |
Trends Biotechnol
January 2025
College of Biological Sciences, China Agricultural University, Beijing 100193, China. Electronic address:
Engineering nitrogen fixation in cereals could reduce usage of chemical nitrogen fertilizers. Here, a nitrogenase biosynthesis pathway comprising 13 genes (nifB nifH nifD nifK nifE nifN nifX hesA nifV nifS nifU groES groEL) was introduced into rice by transforming multigene vectors and subsequently by sexual crossing between transgenic rice plants. Genome sequencing analysis revealed that 13 nif genes in F hybrid rice lines L12-13 and L8-17 were inserted at two loci on rice chromosome 1.
View Article and Find Full Text PDFJ Gen Appl Microbiol
January 2025
Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo.
We previously constructed an Escherichia coli strain expressing 16 nitrogen fixation (nif) and 2 nif-related genes from Azotobacter vinelandii and improved nitrogenase activity to some extent by enhancing NifH-related functions. In the present study, we analyzed the formation of dinitrogenase, a heterotetrameric NifDK, produced in E. coli, using gel-filtration chromatography and blue native PAGE to gain insight into further increases in nitrogenase activity.
View Article and Find Full Text PDFHortic Res
January 2025
College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
The circadian clock mediates metabolic functions of plants and rhythmically shapes structure and function of microbial communities in the rhizosphere. However, it is unclear how the circadian rhythm of plant hosts regulates changes in rhizosphere bacterial and fungal communities and nutrient cycles. In the present study, we measured diel changes in the rhizosphere of bacterial and fungal communities, and in nitrogen (N) and phosphorus (P) cycling in 20-year-old tea plantations.
View Article and Find Full Text PDFSci Total Environ
January 2025
Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.
Microlife
October 2024
Institute for General Microbiology, Christian-Albrechts-University, Am Botanischen Garten 1-9, 24118 Kiel, Germany.
is a model organism, providing a platform to explore methanoarchaeal regulation mechanisms on the transcriptional and translational level. This study investigates and evaluates various molecular tools to allow inducible gene expression in . (i) The TetR/TetO system was utilized to induce expression of a designed antisense RNA directed against sRNA allowing to increase transcripts of asRNA (500-fold), resulting in a significant decrease of sRNA levels (tetracycline-induced knockdown mutant).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!