Chlamydomonas reinhardtii chloroplast factory construction for formate bioconversion.

The photosynthetic autotrophic production of microalgae is limited by the effective supply of carbon and light energy, and the production efficiency is lower than the theoretical value. Represented by methanol, C1 compounds have been industrially produced by artificial photosynthesis with a solar energy efficiency over 10%, but the complexity of artificial products is weak. Here, based on a construction of chloroplast factory, green microalgae Chlamydomonas reinhardtii CC137c was modified for the bioconversion of formate for biomass production.

Engineering a solar formic acid/pentose (SFAP) pathway in Escherichia coli for lactic acid production.

Microbial CO fixation into lactic acid (LA) is an important approach for low-carbon biomanufacturing. Engineering microbes to utilize CO and sugar as co-substrates can create efficient pathways through input of moderate reducing power to drive CO fixation into product. However, to achieve complete conservation of organic carbon, how to engineer the CO-fixing modules compatible with native central metabolism and merge the processes for improving bioproduction of LA is a big challenge.

Biocatalysis of CO and CH: Key enzymes and challenges.

Mitigating greenhouse gas emissions is a critical challenge for promoting global sustainability. The utilization of CO and CH as substrates for the production of valuable products offers a promising avenue for establishing an eco-friendly economy. Biocatalysis, a sustainable process utilizing enzymes to facilitate biochemical reactions, plays a significant role in upcycling greenhouse gases.

A kinetic-assisted growth curve prediction method for Chlamydomonas reinhardtii incorporating transfer learning.

Traditional predictions of microalgal growth states rely on empirical or easily implementable kinetic models, leading to significant biases and elevated cost. This study proposes a kinetic-assisted machine learning method for predicting the growth curve of microalgal biomass under small sample conditions. Firstly, a microalgae growth kinetic model is constructed based on the logistic model.

Enhancing photosynthetic CO fixation by assembling metal-organic frameworks on Chlorella pyrenoidosa.

The CO concentration at ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is crucial to improve photosynthetic efficiency for biomass yield. However, how to concentrate and transport atmospheric CO towards the Rubisco carboxylation is a big challenge. Herein, we report the self-assembly of metal-organic frameworks (MOFs) on the surface of the green alga Chlorella pyrenoidosa that can greatly enhance the photosynthetic carbon fixation.

Crosslinker Nanocarriers Delivery to Chloroplasts for Mapping of Photosynthetic Membrane Protein Complexes in Living Cells.

Photosynthesis, as the core of solar energy biotransformation, is driven by photosynthetic membrane protein complexes in plants and algae. Current methods for intracellular photosynthetic membrane protein complex analysis mostly require the separation of specific chloroplasts or the change of the intracellular environment, which causes the missing of real-time and on-site information. Thus, we explored a method for crosslinking and mapping of photosynthetic membrane protein complexes in the chloroplasts of living () cells under cultural conditions.

The Carbon Source Effect on the Production of Ralstonia eutropha H16 and Proteomic Response Underlying Targeting the Bioconversion with Solar Fuels.

Chemoautotrophic bacterium Ralstonia eutropha H16 can fix CO to bioplastic and is potentially useful for CO neutralization. Targeting the solar fuel-based plastic biomanufactory, the polyhydroxybutyrate (PHB) production between heterotrophy and chemoautotrophy conditions was evaluated and the proteomic responses of the R. eutropha H16 cells to different carbon and energy sources were investigated.

Quantitative analysis on photon numbers received per cell for triggering β-carotene accumulation in Dunaliella salina.

Accumulation of β-carotene in Dunaliella salina is highly dependent on light exposure intensity and duration, but quantitative analysis on photon numbers received per cell for triggering β-carotene accumulation is not available so far. In this study, experiment results showed that significant β-carotene accumulation occurred after at least 8 h illumination at 400 µmol photons·m·s. To quantify the average number of photons received per cell, correlations of light attenuation with light path, biomass concentration, and β-carotene content were, respectively, established using both Lambert-Beer and Cornet models, and the latter provided better simulation.

Cultivation of fractionated cells from a bioactive-alkaloid-bearing marine sponge Axinella sp.

Sponges are among the most primitive multicellular organisms and well-known as a major source of marine natural products. Cultivation of sponge cells has long been an attractive topic due to the prominent evolutionary and cytological significance of sponges and as a potential approach to supply sponge-derived compounds. Sponge cell culture is carried out through culturing organized cell aggregates called 'primmorphs.

A Quick Look Back at the Microalgal Biofuel Patents: Rise and Fall.

Microalgae is a promising organism as the feedstock of the next generation biofuels, as well as high value nature products, such as astaxanthin, normally under certain stress cultivation conditions. With the clear industrialization targets, there have been two waves of microalgae R&D from the last century and showed obvious energy-driven trends. The overall R&D came into a valley now, however, the promising is still there.

Galactolipid DGDG and Betaine Lipid DGTS Direct De Novo Synthesized Linolenate into Triacylglycerol in a Stress-Induced Starchless Mutant of Chlamydomonas reinhardtii.

The increasing demand for triacylglycerol (TAG) enriching polyunsaturated fatty acids (PUFAs) has led to a surge of interest in microalgal TAG metabolism. Polar membrane lipids serve as the desaturation carrier for PUFA, and the functional group of PUFA can be incorporated into TAG. Monogalactoglycerolipid has been found to provide the de novo synthesized oleate acyl group or the nascent polyunsaturated diacylglycerol backbone for TAG biosynthesis in the model green alga, Chlamydomonas reinhardtii.

Monogalactosyldiacylglycerols with High PUFA Content From Microalgae for Value-Added Products.

Monogalactosyldiacylglycerols (MGDGs) from microalgae containing a high proportion of polyunsaturated fatty acids (PUFAs) have enormous potential applications in various industries. In this study, the productivity and fatty acid composition of MGDGs from three microalgae in commercialized production, Chlorella sorokiniana GT, Nannochloropsis oceanica IMET1, and Arthrospira platensis, were evaluated under nitrogen-sufficient (+N) and nitrogen-deficient (-N) conditions. Under +N conditions, higher productivities of MGDGs from C.

Production and structural characterization of a new type of polysaccharide from nitrogen-limited cultivated in outdoor industrial-scale open raceway ponds.

Background: Carbohydrates are major biomass source in fuel-targeted biorefinery. is the largest commercialized microalgae with good environmental tolerance and high biomass production. However, the traditional target of cultivation is the protein, which is the downstream product of carbohydrates.

The heat-tolerance evaluation of an Isochrysis zhangjiangensis mutant generated by atmospheric and room temperature plasmas.

Isochrysis zhangjiangensis is widely used in the marine aquaculture as larval feed, especially for filter feeding cultures, as well as a good candidate for biofuels. However, the optimal cultivation temperature for I. zhangjiangensis is below 30 °C and this stain is seriously affected by high temperature, which causes the limited application during the summer.

Expanding of Phospholipid:Diacylglycerol AcylTransferase (PDAT) from Saccharomyces cerevisiae as Multifunctional Biocatalyst with Broad Acyl Donor/Acceptor Selectivity.

Triacylglycerols are considered one of the most promising feedstocks for biofuels. Phospholipid:diacylglycerol acyltransferase (PDAT), responsible for the last step of triacylglycerol synthesis in the acyl-CoA-independent pathway, has attracted much attention by catalyzing membrane lipid transformation. However, due to lack of biochemical and enzymatic studies, PDAT has not carried forward in biocatalyst application.

Stereoselective catalysis controlled by a native leucine or variant isoleucine wing-gatekeeper in 2-haloacid dehalogenase.

Comprehensively understanding enzymatic stereoselectivity will assist in the creation of new enzymes for producing optically pure compounds for chemical applications. The essential features for selecting enantiomers are controlled by particular residues or regions of the enzymes. We report a stereoselective mechanism in the D-2-haloacid dehalogenase HadD AJ1, in which L288 is identified as a gatekeeper in the access channel that strictly recognizes D-enantiomers.

The Δ'-guided supply of nitrogen in culture medium facilitates sustainable production of TAG in IMET1.

Background: Triacylglycerol (TAG) from photosynthetic microalgae is a sustainable feedstock for biodiesel production. Physiological stress triggers microalgal TAG accumulation. However excessive physiological stress will impair the photosynthesis system seriously thus decreasing TAG productivity because of the low biomass production.

The synchronous TAG production with the growth by the expression of chloroplast transit peptide-fused ScPDAT in .

Background: The synchronous triacylglycerol (TAG) production with the growth is a key step to lower the cost of the microalgae-based biofuel production. Phospholipid: diacylglycerol acyltransferase (PDAT) has been identified recently and catalyzes the phospholipid contributing acyl group to diacylglycerol to synthesize TAG, and is considered as the important source of TAG in .

Results: Using a chimeric Hsp70A-RbcS2 promoter, exogenous PDAT form fused with a chloroplast transit peptide was expressed in CC-137.