There are structural and functional differences in SmtB homologs, metal-responsive transcription factors responsible for sensing of excess heavy metal ions in marine and freshwater cyanobacterial strains. The structure of SmtB from freshwater Synechococcus sp. strain PCC 7942 is elucidated with nuclear magnetic resonance (NMR) and crystallography techniques. But knowledge about the functioning of SmtB homologs from marine species is limited till date. To enable NMR spectroscopic studies for investigating structural and functional aspects, modified protocols with higher yields of isotopically labeled SmtB, from marine species like Synechococcus sp. PCC 7002 are essential. In this study, smtB gene was cloned from genome of Synechococcus sp. PCC 7002 and overexpression protocol for recombinant SmtB was standardized in Escherichia coli containing T7 RNA polymerase/promoter system. Further, the protocol for large-scale production, isotope labeling with (15)N, and purification of recombinant SmtB in E. coli BL21(DE3)/pLysS cells was developed. Purified recombinant protein was successfully used for NMR spectroscopy experiments. These results indicate that the overexpression technique now developed is applicable to the structural and functional studies for the proteins being homologous to cyanobacterial SmtB from Synechococcus sp. PCC 7002.
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http://dx.doi.org/10.1007/s10930-013-9525-y | DOI Listing |
Funct Integr Genomics
January 2025
The Energy and Resources Institute, Lodi Road, New Delhi, 110003, India.
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View Article and Find Full Text PDFJ Plant Res
December 2024
Graduate School of Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, 422-8529, Japan.
Salinity and light markedly influence cyanobacterial viability. High salinity disrupts the osmotic balance, while excess light energy affects redox potential in the cells. Regulating the ratio of saturated and unsaturated alka(e)ne and fatty acids in cyanobacteria is thought to have crucial roles in coping with these stresses by regulating membrane fluidity.
View Article and Find Full Text PDFSci Rep
December 2024
Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan.
A circadian clock is reconstituted in vitro by incubating three proteins, KaiA, KaiB, and KaiC from the non-nitrogen-fixing cyanobacterium Synechococcus elongatus PCC 7942 in the presence of ATP. Leptolyngbya boryana is a filamentous cyanobacterium that grows diazotrophically under microoxic conditions. Among the aforementioned proteins, KaiC is the main clock oscillator belonging to the RecA ATPase superfamily.
View Article and Find Full Text PDFJ Biosci Bioeng
December 2024
Engineering Biology Research Center, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan; Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan. Electronic address:
In bacteria, mechanosensitive channels mediate extracellular release of osmolytes, including glutamate, functioning as safety valves upon osmotic downshift. In cyanobacteria, the role of mechanosensitive channels has not been completely elucidated. Recently, the glycogen-deficient ΔglgC mutant of Synechococcus elongatus PCC 7942 was found to release glutamate extracellularly, giving rise to a hypothesis that the role of mechanosensitive channels in cyanobacteria is conserved.
View Article and Find Full Text PDFBiotechnol Bioeng
December 2024
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona, USA.
Quantification of cyanobacterial CO fixation rates is vital to determining their potential as industrial strains in a circular bioeconomy. Currently, however, CO fixation rates are most often determined through indirect and/or low-resolution methods, resulting in an incomplete picture of both dynamic behaviors and total carbon fixation potential. To address this, we developed the "Automated Carbon and CO Experimental Sampling System" (ACCESS); a low-cost system for in situ off-gas analysis that supports the automated acquisition of high-resolution volumetric CO uptake rates from multiple cyanobacterial cultures in parallel.
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