Rapid differentiation of phenotypically and genotypically similar Synechococcus elongatus strains by PCR fingerprinting

Study on the Bioconversion of Curcumin to Calebin-A Using Spirulina subsalsa and Its Taxonomic Resolution Using 16S rRNA Analysis

Due to morphological convergence and the application of numerous taxonomic concepts, the systematics of filamentous cyanobacteria is still a significant problem. The incorporation and integration of modern molecular, cyto-morphological and ecological approaches in cyanobacterial taxonomy are essential and must be acknowledged as the valid methods for the development of their modern systematics. In this study, method of using 16S rRNA gene sequences to infer the genetic relationships of twelve freshwater cyanobacterial isolates amongst themselves was evaluated. The taxonomic resolution was inferred from their phylogenetic tree, in silico restriction digestion analysis and secondary structure prediction. These methods allowed cyanobacterial genera to be well distinguished with their genotypic and phenotypic differences. Amongst twelve strains, Spirulina subsalsa with highest protein content was used in this study for evaluating the stability of Curcumin which is a curcuminoid compound reported from Curcuma longa. Though they have wide properties, they still lack stability and bioavailability. It is reported previously that microbes are used for biotransformation and act as a carrier molecule. Therefore, in this study, Spirulina incorporated with curcumin resulted with pH stability of curcumin and were found to have a biotransformation into Calebin-A, curcuminoid compound originally present in smaller amount (0.005%) in C. longa with various biomedical applications.

Release of ecologically relevant metabolites by the cyanobacterium Synechococcus elongates CCMP 1631

Photoautotrophic plankton in the surface ocean release organic compounds that fuel secondary production by heterotrophic bacteria. Here we show that an abundant marine cyanobacterium, Synechococcus elongatus, contributes a variety of nitrogen-rich and sulfur-containing compounds to dissolved organic matter. A combination of targeted and untargeted metabolomics and genomic tools was used to characterize the intracellular and extracellular metabolites of S. elongatus. Aromatic compounds, such as 4-hydroxybenzoic acid and phenylalanine, as well as nucleosides (e.g. thymidine, 5'-methylthioadenosine, xanthosine), the organosulfur compound 3-mercaptopropionate, and the plant auxin indole 3-acetic acid, were released by S. elongatus at multiple time points during its growth. Further, the amino acid kynurenine was found to accumulate in the media even though it was not present in the predicted metabolome of S. elongatus. This indicates that some metabolites, including those not predicted by an organism's genome, are likely excreted into the environment as waste; however, these molecules may have broader ecological relevance if they are labile to nearby microbes. The compounds described herein provide excellent targets for quantitative analysis in field settings to assess the source and lability of dissolved organic matter in situ.