Gene transcription and antioxidants production in Arthrospira (Spirulina) platensis grown under temperature variation

Abstract

Aim To investigate the transcription of selected antioxidants and relevant genes under varying temperature conditions, and to identify the optimum temperature for antioxidants production by Arthrospira platensis. Methods and Results The dry weight (DW), pigment production, antioxidants production and gene transcription were examined in A. platensis growing under three temperatures of 23, 30 and 37°C. The cyanobacterial DW was highest in the high temperatures (30 and 37°C), while the pigments, such as Chl a, carotenoids, C‐phycocyanin and total phycobiliprotein contents, showed their maximum value at 30°C. The total soluble protein and carbohydrate contents were highest at 30°C. Lipid peroxidation, as a marker for thermal stress, was high at 23°C, while higher temperatures remarkably reduced lipid peroxidation levels. Antioxidants activity was increased by 1·5‐fold at 30°C and temperature fluctuations induced the antioxidant enzyme activities. The transcriptional abundance of heat shock protein (HSP90), glutamate synthase (GOGAT), delta‐9 desaturase (desC), iron‐superoxide dismutase (FeSOD) and the large subunit of Rubisco (rbcL) genes was measured under the same temperatures. Conclusion The optimal temperature for growth, biochemical constituents and antioxidants of A. platensis is 30°C while some antioxidant enzyme activity increased at lower and higher temperatures. Significance and Impact of the Study The study showed the significance of temperature for growth, enzymatic and non‐enzymatic antioxidants and gene expression in A. platensis. This contributes to the knowledge of culturing A. platensis to harvest specific antioxidants or as an antioxidant‐rich food source.

Modification of Some Structural and Functional Parameters of Living Culture of Arthrospira platensis as the Result of Selenium Nanoparticle Biosynthesis

“…In the case of the influence of selenium on A. platensis, an increase in the transcriptional abundance of hsp90 (4.4-times compared to the control) was observed, which points to a need to maintain the stability of cellular proteins. The same upregulation of hsp90 was observed, for example, when growing spirulina at temperatures lower or higher than the optimum one [ 42 ]. The role of HSPs in the adaptation to oxidative stress conditions caused by physical (radiation) and chemical factors (action of methyl viologen) was demonstrated in Synechococcu sp.…”

“…The first enzyme catalyzes the dismutation reaction of the superoxide radical into hydrogen peroxide, and the peroxidase—the decomposition reaction of peroxide into water and oxygen. In addition to the production of antioxidant enzymes, the defense mechanisms of cyanobacteria in relation to stress factors include the inclusion of other genes associated with the stress response, such as the genes of heat-shock proteins (HSPs), ribulose bisophosphate carboxylase/oxygenase (Rubisco), glutamate synthase and GOGAT [ 42 ].…”

“…HSPs are involved not only in the case of thermal stress, but also in other forms of stress, because they ensure the stability of proteins and the avoidance of their misfolding [ 42 , 43 , 44 , 45 ]. In the case of the influence of selenium on A. platensis, an increase in the transcriptional abundance of hsp90 (4.4-times compared to the control) was observed, which points to a need to maintain the stability of cellular proteins.…”

“…Gene rbcL (the large subunit of ribulose bisphosphate carboxylase/oxygenase; Rubisco) is involved in ensuring the growth of photosynthetic organisms and the metabolic activity necessary to maintain life, as the GOGAT gene, which codes the glutamate synthase enzyme [ 42 , 43 , 44 , 45 , 46 ]. rbcL is directly involved in carbon assimilation, thus, ensuring the process of photosynthesis and organism growth, and GOGAT catalyzes the reaction of glutamate formation from glutamines and 2-oxoglutarate.…”

Salinity matters the most: How environmental factors shape the diversity and structure of cyanobacterial mat communities in high altitude arid ecosystems

“…In less saline environments cyanobacteria store disaccharides (sucrose and trehalose) in their cells, in more saline ones, they accumulate glucosylglycerol in cytoplasm, and glycine betaine in moderately saline and hypersaline ( Oren, 2015 ). High water temperature also requires various physiological adaptations, such as producing antioxidants, or inducing various defense genes, for example genes responsible for biosynthesis of heat shock proteins or desaturases, enzymes responsible for fatty acids desaturations in membranes ( Ismaiel and Piercey-Normore, 2021 ). Not only induction of certain genes but also their number, as in the case of HSPs genes, is connected with the ability of cyanobacterial species to grow in stressful conditions, for example high temperature environments ( Jasser et al, 2022 ).…”