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Biological control of cyanobacteria is a well-researched area with a central focus on laboratory-scale studies. Numerous reports have been made on algicidal isolates, with bacteria as a major component of the antagonists. The research in this review draws a brief summary of what is currently known in the area of freshwater cyanobacteria being inhibited by bacterial isolates. Proteobacteria, Bacteroidetes and Firmicutes are among the most commonly reported phyla of bacteria associated with or employed in this research area. However, there are limited reports of upscaling these control measures beyond the laboratory scale. Lytic control agents are the most commonly reported in the literature with subsequent cyanotoxin release. From a water quality perspective, this is not feasible. Based on the available literature, temperature, pH and nutrient changes have been explored in this short review as possible contributors to less optimal bacterial performance. Moreover, the investigation into optimising some of these parameters may lead to increased bacterial performance and, therefore, viability for upscaling this biological control. Through the compilation of current research, this review offers insight to live predator-prey cell interactions between cyanobacteria and algicidal bacteria. [ABSTRACT FROM AUTHOR]

Cyanobacteria are an ideal host for biofuel production. Although efforts have been made to genetically engineer cyanobacteria for efficient production of biofuels and other important chemicals, the tools that can be applied to cyanobacteria are still limited. A new gene regulation tool, riboregulator, has been examined for application in cyanobacteria. A riboregulator is a nature-inspired RNA tool, which is composed of two artificially designed RNA fragments. Owing to its high specificity and efficacy, it is suitable for metabolic engineering in cyanobacteria, and several studies have been done to optimize and improve the function of the riboregulator. In this review, we focus on the recent improvements made to riboregulators and compare them with other RNA-mediated gene regulation tools developed in cyanobacteria to investigate future applications of riboregulators. [ABSTRACT FROM AUTHOR]

In our search for thermophilic and acid-tolerant nucleoside 2′-deoxyribosyltransferases (NDTs), we found a good candidate in an enzyme encoded by Chroococcidiopsis thermalis PCC 7203 (CtNDT). Biophysical and biochemical characterization revealed CtNDT as a homotetramer endowed with good activity and stability at both high temperatures (50-100 °C) and a wide range of pH values (from 3 to 7). CtNDT recognizes purine bases and their corresponding 2′-deoxynucleosides but is also proficient using cytosine and 2′-deoxycytidine as substrates. These unusual features preclude the strict classification of CtNDT as either a type I or a type II NDT and further suggest that this simple subdivision may need to be updated in the future. Our findings also hint at a possible link between oligomeric state and NDT’s substrate specificity. Interestingly from a practical perspective, CtNDT displays high activity (80-100%) in the presence of several water-miscible co-solvents in a proportion of up to 20% and was successfully employed in the enzymatic production of several therapeutic nucleosides such as didanosine, vidarabine, and cytarabine. [ABSTRACT FROM AUTHOR]