All the rage this year about Bacterial Wilt/ Decline has me wondering about these unintended consequences when it comes to our obsession with plant health. “You don’t understand”, a competent golf turf manager said to me about 10 years ago, “I use these biostimulants because I grow grass on the edge”.
Close-up of yellow etiolation associated with Bacterial Wilt. In this case the plants did not decline and have remained in this state for 3 weeks.
oxygen gas by plant and bacterial photosynthesis
Th is is clearly d e m o nstrated in the photosynthetic sulfur bacteria, which Dxidize inorganic sulfur compounds and reduce carbon dioxide under the influence of light.
Plant Pigments & Photosynthesis - bozemanscience
To this end, there is a need for the development of industrial technology which makes use of biological principles in a sophisticated manner.
Biological energy conversions can be categorized into two groups: i) photosynthesis (the process whereby solar energy is fixed to yield energy useful to organisms and industry), and ii) biomass conversion (the product of photosynthesis) into energy.
Plant Energy Transformations-Photosynthesis
Now some panic and run for the Mycoshield because a diagnostic technician said they have bacterial wilt. Now raise your hand if you think our society needs MORE anti-biotics introduced into the environment. You think the current palette of plant health products is causing unintended consequences, stick around for the antibiotic resistant organisms we might create by spraying tetracycline every seven days!
Chapter 2 - Energy conversion by photosynthetic …
One of the fascinating characteristics of photosynthesis is its capacity for repair, self-renewal, and energy storage within chemical bonds. Given the evolutionary history of plant photosynthesis and the patchwork nature of many of its components, it is safe to assume that the light reactions of plant photosynthesis can be improved by genetic engineering (Leister, ). The evolutionary precursor of chloroplasts was a microorganism whose biochemistry was very similar to that of present-day cyanobacteria. Many cyanobacterial species are easy to manipulate genetically and grow robustly in liquid cultures that can be easily scaled up into photobioreactors. Therefore, cyanobacteria such as Synechocystis sp. PCC 6803 (hereafter “Synechocystis”) have widely been used for decades as model systems to study the principles of photosynthesis (Table ). Indeed, genetic engineering based on homologous recombination is well-established in Synechocystis. Moreover, new genetic engineering toolkits, including marker-less gene deletion and replacement strategies needing only a single transformation step (Viola et al., ) and novel approaches for chromosomal integration and expression of synthetic gene operons (Bentley et al., ), allow for large-scale replacement and/or integration of dozens of genes in reasonable time frames. This makes Synechocystis a very attractive basis for the experimental modification of important processes like photosynthesis, and it also suggests innovative ways of improving modules of related eukaryotic pathways, among them the combination of cyanobacterial and eukaryotic elements using the tools of synthetic biology.
Northern Illinois Department of Biological Sciences
In plants, the activity of the Calvin cycle (in particular the RuBisCO-mediated carbon fixation step) is considered to represent the major brake on photosynthetic efficiency under saturating irradiance and limiting CO2 concentrations (Quick et al., ; Stitt et al., ; Furbank et al., ). Autotrophic growth of Synechocystis, on the other hand, is constrained by the rate of phosphoglycerate reduction, owing to limitations on the ATP/NADPH supply from the light reactions (Marcus et al., ). In fact, cyanobacteria cannot absorb all incoming sunlight due to light reflection, dissipation, and shading effects. In some cases, significant numbers of the photons absorbed by the antennae are not used for energy conversion due to dissipation mechanisms. It has therefore been proposed that uneven light distribution could be avoided by using cell cultures with smaller antenna sizes packed in high-density cell cultures, thus allowing good light penetration into the inner parts of the reactor. Proof of principle for this concept has been obtained in the green alga Chlamydomonas reinhardtii (Beckmann et al., ), but antenna truncations in Synechocystis have so far failed to enhance biomass production (Page et al., ). Indeed, increased truncations of phycobilisomes were associated with reductions in photoautotrophic productivity, which were attributed to marked decrease in the PSI:PSII ratio (Collins et al., ).