The iron deficiency-dependent regulation of isiAB transcription in Synechocystis sp. PCC 6803 was analyzed by fusion of modified isiAB promoter fragments to gfp and in vivo quantification of Gfp fluorescence. For the putative Fur box only a slight repressing impact on promoter activity could be shown. In a heteroallelic fur mutant a corresponding incomplete repression of isiAB transcription under iron-replete conditions confirmed the role of Fur in isiAB regulation. However, a 90 bp region upstream of the putative -35 box of the isiAB promoter was essential for full promoter activity under iron-deplete conditions. This pattern indicates a dual promoter regulation by both a repressing mechanism exhibited via the Fur system and an unknown activating mechanism.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/S0378-1097(03)00689-X | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Investigation of the effect of salt stress on photosynthetic electron transport pathways in the Synechocystis PCC 6803 cyanobacterium.
Physiol Plant
January 2025
Institute of Plant Biology, HUN-REN Biological Research Centre, Szeged, Hungary.
Cyanobacteria are important model organisms for studying the process of photosynthesis and the effects of environmental stress factors. This study aimed to identify the inhibitory sites of NaCl in the whole photosynthetic electron transport in Synechocystis sp. PCC 6803 WT cells by using multiple biophysical tools.
View Article and Find Full Text PDFExploring and increased acetate biosynthesis in Synechocystis PCC 6803 through insertion of a heterologous phosphoketolase and overexpressing phosphotransacetylase.
Metab Eng
January 2025
Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden. Electronic address:
Acetate is a biological anion with many applications in the chemical and food industries. In addition to being a common microbial fermentative end-product, acetate can be produced by photosynthetic cyanobacteria from CO using solar energy. Using wild-type cells of the unicellular model cyanobacterium Synechocystis PCC 6803 only low levels of acetate are observed outside the cells.
View Article and Find Full Text PDFA High-Resolution Crystallographic Study of Cytochrome c6: Structural Basis for Electron Transfer in Cyanobacterial Photosynthesis.
Int J Mol Sci
January 2025
College of Chemistry and Life Science, Beijing University of Technology, Beijing 100124, China.
Cyanobacterial cytochrome c6 (Cyt c6) is crucial for electron transfer between the cytochrome b6f complex and photosystem I (PSI), playing a key role in photosynthesis and enhancing adaptation to extreme environments. This study investigates the high-resolution crystal structures of Cyt c6 from PCC 7942 and PCC 6803, focusing on its dimerization mechanisms and functional implications for photosynthesis. Cyt c6 was expressed in using a dual-plasmid co-expression system and characterized in both oxidized and reduced states.
View Article and Find Full Text PDF[Promotion of sp. on the photosynthetic growth of microalgae exposed to high concentrations of formate].
Sheng Wu Gong Cheng Xue Bao
January 2025
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China.
Formate is an important solar fuel, with large application potential in bioconversion. Especially, the win-win collaboration is achieved when formate is applied to the cultivation of microalgae, which combines the advantages from both artificial and natural photosynthesis. However, the inhibition of formate on the photosynthetic electron transport hinders the application of formate at high concentrations.
View Article and Find Full Text PDFLight-driven biotransformations in recombinant cyanobacteria benefit from the atom-efficient regeneration of reaction equivalents like NADPH from water and light by oxygenic photosynthesis. The self-shading of photosynthetic cells throughout the reaction volume, along with the need for extended light paths, limits adequate light supply and significantly restricts the potential for upscaling. Here, we present a flat panel photobioreactor (1 cm optical path length) as a scalable system to provide efficient illumination at high cell densities.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!