cyanobacteria
Editor's Pick Research Article | Ecological and Evolutionary ScienceTiming the Evolutionary Advent of Cyanobacteria and the Later Great Oxidation Event Using Gene Phylogenies of a SunscreenThe advent of cyanobacteria, with their invention of oxygenic photosynthesis, and the Great Oxidation Event are arguably among the most important events in the evolutionary history of life on Earth. Oxygen is a significant toxicant to all life, but its accumulation in the atmosphere also enabled the successful development and proliferation of many aerobic organisms, especially metazoans. The currently favored dating of the Great...
Research Article | Applied and Environmental ScienceComparative Genomics of Cyanobacterial Symbionts Reveals Distinct, Specialized Metabolism in Tropical Dysideidae SpongesNatural products provide the inspiration for most clinical drugs. With the rise in antibiotic resistance, it is imperative to discover new sources of chemical diversity. Bacteria living in symbiosis with marine invertebrates have emerged as an untapped source of natural chemistry. While symbiotic bacteria are often recalcitrant to growth in the lab, advances in metagenomic sequencing and assembly now make it possible to access their...
Research Article | Molecular Biology and PhysiologyCoordination of Polyploid Chromosome Replication with Cell Size and Growth in a CyanobacteriumPolyploidy has evolved many times across the kingdom of life. The relationship between cell growth and chromosome replication in bacteria has been studied extensively in monoploid model organisms such as Escherichia coli but not in polyploid organisms. Our study of the polyploid cyanobacterium...
Editor's Pick Research Article | Ecological and Evolutionary ScienceThe Transcriptional Cycle Is Suited to Daytime N2 Fixation in the Unicellular Cyanobacterium “Candidatus Atelocyanobacterium thalassa” (UCYN-A)The symbiotic N2-fixing cyanobacterium UCYN-A, which is closely related to Braarudosphaera bigelowii, and its eukaryotic algal host have been shown to be globally distributed and important in open-ocean N2 fixation. These unique cyanobacteria have reduced metabolic capabilities, even lacking genes for oxygenic photosynthesis and carbon fixation....
Research Article | Molecular Biology and PhysiologyThe Widely Conserved ebo Cluster Is Involved in Precursor Transport to the Periplasm during Scytonemin Synthesis in Nostoc punctiformeElucidating the biochemical and genetic basis of scytonemin constitutes an interesting challenge because of its unique structure and the unusual fact that it is partially synthesized in the periplasmic space. Our work points to the ebo gene cluster, associated with the scytonemin operon of cyanobacteria, as being responsible for the excretion of scytonemin intermediates from the cytoplasm into the periplasm during biosynthesis...
- Research ArticleEngineering Nitrogen Fixation Activity in an Oxygenic Phototroph
Application of chemically synthesized nitrogen fertilizers has revolutionized agriculture. However, the energetic costs of such production processes and the widespread application of fertilizers have raised serious environmental issues. A sustainable alternative is to endow to crop plants the ability to fix atmospheric N2in situ. One long-term approach is to transfer all nif genes from a prokaryote to plant...
- Research ArticleAdjustments to Photosystem Stoichiometry and Electron Transfer Proteins Are Key to the Remarkably Fast Growth of the Cyanobacterium Synechococcus elongatus UTEX 2973
As the global population increases, the amount of arable land continues to decrease. To prevent a looming food crisis, crop productivity per acre must increase. A promising target for improving crop productivity is increasing the photosynthetic rates in crop plants. Cyanobacteria serve as models for higher plant photosynthetic systems and are an important test bed for improvements in photosynthetic productivity. In this study, we...
- Editor's Pick Research ArticleOn the Origin of Reverse Transcriptase-Using CRISPR-Cas Systems and Their Hyperdiverse, Enigmatic Spacer Repertoires
While the majority of CRISPR-Cas immune systems adapt to foreign genetic elements by capturing segments of invasive DNA, some systems carry reverse transcriptases (RTs) that enable adaptation to RNA molecules. From analysis of available bacterial sequence data, we find evidence that RT-based RNA adaptation machinery has been able to join with CRISPR-Cas immune systems in many, diverse bacterial species. To investigate whether the...