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At least 667 records · Page 37

RNA-guided nucleic acid modifying enzymes and methods of use thereof

The present disclosure provides CasX proteins, nucleic acids encoding the CasX proteins, and modified host cells comprising the CasX proteins and/or nucleic acids encoding same. CasX proteins are useful in a variety of applications, which are provided. The present disclosure provides CasX guide RNAs that bind to and provide sequence specificity to the CasX proteins, nucleic acids encoding the CasX guide RNAs, and modified host cells comprising the CasX guide RNAs and/or nucleic acids encoding same. CasX guide RNAs are useful in a variety of applications, which are provided. The present disclosure provides archaeal Cas9 polypeptides and nucleic acids encoding same, as well as their associated archaeal Cas9 guide RNAs and nucleic acids encoding same.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Thermophilic and thermoacidophilic biopolymer-degrading genes and enzymes from Alicyclobacillus acidocaldarius and related organisms, methods

Isolated and/or purified polypeptides and nucleic acid sequences encoding polypeptides from Alicyclobacillus acidocaldarius are provided. Further provided are methods of at least partially degrading, cleaving, or removing polysaccharides, lignocellulose, cellulose, hemicellulose, lignin, starch, chitin, polyhydroxybutyrate, heteroxylans, glycosides, xylan-, glucan-, galactan-, or mannan-decorating groups using isolated and/or purified polypeptides and nucleic acid sequences encoding polypeptides from Alicyclobacillus acidocaldarius.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Thermophilic and thermoacidophilic metabolism genes and enzymes from Alicyclobacillus acidocaldarius and related organisms, methods

Isolated and/or purified polypeptides and nucleic acid sequences encoding polypeptides from Alicyclobacillus acidocaldarius are provided. Further provided are methods for modulating or altering metabolism in a cell using isolated and/or purified polypeptides and nucleic acid sequences from Alicyclobacillus acidocaldarius.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

A nitrogenase-like enzyme system catalyzes methionine, ethylene, and methane biogenesis

Bacterial production of gaseous hydrocarbons like ethylene and methane affect soil environments and atmospheric climate. We demonstrate that biogenic methane and ethylene from terrestrial and freshwater bacteria are directly produced by a previously unknown methionine biosynthesis pathway. This pathway, present in numerous species, employs a nitrogenase-like reductase that is distinct from known nitrogenases and nitrogenase-like reductases. It specifically functions in C-S bond breakage to reduce ubiquitous and significant volatile organic sulfur compounds such as dimethyl sulfide. Liberated methanethiol serves as the immediate precursor to methionine, while ethylene or methane is released into the environment. Anaerobic ethylene production by this pathway apparently explains the origin and long- standing observation of ethylene accumulation in oxygen-depleted soils. Methane production bolsters the accumulating evidence that methanogenesis is not exclusively archaeal.

North, Justin A.↗

Gene targets for improved enzyme production in fungi

Fungi that are genetically inactivated for the mstC gene (or a homolog thereof) are provided, which can also be genetically modified to increase production of heterologous proteins from a glucoamylase promoter. Methods of using these fungi, for example to degrade a biomass, are also provided.

Baker, Scott E.↗

Production of hydroxylated and methoxylated flavonoids in yeast by expression specific enzymes

Recombinant yeast that are genetically modified to contain and express genes or gene pathways that produce hydroxylated and/or methoxylated flavonoids are provided. The genes or gene pathways are derived from plants, for example, from sweet basil (Ocimum basilicum) and the hydroxylated and/or methoxylated flavonoids include, for example, 6-methoxylated naringenin, 6-methoxylated luteolin and 6-methoxylated kaempferol.

Gang, David↗

Mutant xylan biosynthetic enzymes capable of dominant suppression of xylan biosynthesis

The present invention provides for a polypeptide capable of dominant suppression of a first naturally occurring IRX10, wherein the polypeptide comprises an amino acid sequence having at least 70% identity as compared to a second naturally occurring IRX10 wherein the polypeptide comprises one or more of the conserved amino acid indicated in FIG. 2 substituted with a different amino acid residue.

Brandon, Andrew↗

RNA-guided nucleic acid modifying enzymes and methods of use thereof

The present disclosure provides CasY proteins, nucleic acids encoding the CasY proteins, and modified host cells comprising the CasY proteins and/or nucleic acids encoding same. CasY proteins are useful in a variety of applications, which are provided. The present disclosure provides CasY guide RNAs that bind to and provide sequence specificity to the CasY proteins, nucleic acids encoding the CasY guide RNAs, and modified host cells comprising the CasY guide RNAs and/or nucleic acids encoding same. CasY guide RNAs are useful in a variety of applications, which are provided. The present disclosure provides methods of identifying a CRISPR RNA-guided endonuclease.

Doudna, Jennifer A.↗

Gene targets for improved enzyme production in fungi

Fungi that are genetically inactivated for the mstC gene (or a homolog thereof) are provided, which can also be genetically modified to increase production of heterologous proteins from a glucoamylase promoter. Methods of using these fungi, for example to degrade a biomass, are also provided.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

RNA-guided nucleic acid modifying enzymes and methods of use thereof

The present disclosure provides CasX proteins, nucleic acids encoding the CasX proteins, and modified host cells comprising the CasX proteins and/or nucleic acids encoding same. CasX proteins are useful in a variety of applications, which are provided. The present disclosure provides CasX guide RNAs that bind to and provide sequence specificity to the CasX proteins, nucleic acids encoding the CasX guide RNAs, and modified host cells comprising the CasX guide RNAs and/or nucleic acids encoding same. CasX guide RNAs are useful in a variety of applications, which are provided. The present disclosure provides archaeal Cas9 polypeptides and nucleic acids encoding same, as well as their associated archaeal Cas9 guide RNAs and nucleic acids encoding same.

Doudna, Jennifer A.↗

Methane monooxygenase enzymes

Improved soluble methane monooxygenases and soluble methane monooxygenase systems are provided.

Clarke, Elizabeth Jane↗

RNA-guided nucleic acid modifying enzymes and methods of use thereof

The present disclosure provides CasX proteins, nucleic acids encoding the CasX proteins, and modified host cells comprising the CasX proteins and/or nucleic acids encoding same. CasX proteins are useful in a variety of applications, which are provided. The present disclosure provides CasX guide RNAs that bind to and provide sequence specificity to the CasX proteins, nucleic acids encoding the CasX guide RNAs, and modified host cells comprising the CasX guide RNAs and/or nucleic acids encoding same. CasX guide RNAs are useful in a variety of applications, which are provided. The present disclosure provides archaeal Cas9 polypeptides and nucleic acids encoding same, as well as their associated archaeal Cas9 guide RNAs and nucleic acids encoding same.

Doudna, Jennifer A.↗

Final Technical Report

The Department of Energy is interested in technologies that support the sustainable production of fuels, chemicals, and other bioproducts from plant biomass, to offset the nation’s reliance on fossil resources. The plant cell wall of energy crops provides the largest reservoir of raw materials for bioproducts. However, the widespread use of plant cell walls is hampered by their complexity and resistance to breakdown. To improve the productivity and cost-effectiveness of using energy crops to generate bioproducts, the fundamental problem of deconstructing plant cell walls must be addressed. This project developed and evaluated an innovative genetic modification technology to produce strategically designed enzymes that specifically accumulate in the plant cell wall. The resulting enzyme-engineered energy crops are expected to grow normally under natural conditions but break down more quickly and easily under high temperature during the production of biobased products. As such, this plant cell wall targeting enzyme engineering effort will reduce the cost of plant cell wall deconstruction and ultimately improve the economics of bioproducts. The overall objective of this project is to develop and evaluate the in-planta enzyme engineering technology to reduce lignocellulose deconstruction cost. The concept was first validated using tobacco plant, a model plant system that is typically used in lab testing for initial concept validation. Then the enzyme optimization was validated using switchgrass, the energy crop to be used to produce bioproducts. There are three specific objectives in this Phase I project: (1) validate the enzyme optimization concept using tobacco plant, a model plant system. (2) validate the enzyme optimization concept using switchgrass. (3) techno-economic analysis (TEA) for further scale-up application. By the end of this project, in-planta enzyme engineering was validated in both tobacco and switchgrass plants, with improved enzyme activity and saccharification efficiency. The in-planta enzyme engineering in Tabacco didn’t have a significant impact on plant growth and development. Transgenic tobacco plants with in-planta cellulose degrading enzymes showed higher biomass digestibility than wild type. Gene construction and transformation in switchgrass was much longer than expected, which delayed the research progress. Besides, in-planta engineering of lignin degrading enzyme is more challenging than cellulose degrading enzyme, in terms of expression detection. Expression of lignin degrading enzyme and cellulose degrading enzyme improved biomass yield and saccharification efficiency of switchgrass, respectively. It is promising to express both genes in switchgrass for optimized overall performance. According to the results of TEA, switchgrass biomass production cost is mainly attributed to by fertility and harvesting. Biomass production profit can increase up to 10-fold depending on biomass price. The PHA production profit is also sensitive to the biomass price. The proposed technology could potentially reduce the biomass deconstruction cost from 33% to 9% of PHA revenue, making the biomass-based PHA competitive to petroleum-based polymers even in case of relatively high biomass price of biomass. Therefore, cultivation of the genetically engineered self-deconstruction switchgrass for Polyhydroxyalkanoate (PHA) production could benefit switchgrass grower and PHA producer with attractive profits for both sectors. This new enzyme optimization approach will be beneficial for bioindustries that use energy crops as feedstocks. It will improve the economic viability of converting energy crops to renewable products that support a sustainable society and helps address the Nation’s long-term strategic needs for renewable products and reduction of reliance on fossil resources.

42 ENGINEERING↗

Cell Free and Immobilization Technologies (CFIT)

Today, several key factors negatively impact the production of fuels and chemicals from renewable sources. Common hindrances in the biological production of biochemicals are: (1) end-product or intermediate toxicity to the microbial biocatalyst, (2) the diversion of carbon to biomass formation, and (3) co-production of undesired byproducts. A particularly attractive alternative is to eliminate the biocatalyst entirely and instead operate the desired metabolic pathways in isolation, thus circumventing the roadblocks of biological toxicity, lower yields, and lack of specificity. However, cell-free enzyme systems still suffer from low productivities owing in part to the effects of free diffusion of intermediates, lack of long term enzyme stability, cofactor cost or inefficient recycling rates, and finally, the cost of enzyme production/purification. This project represents a new effort to propose innovative and cost competitive routes to producing biochemicals from a variety of feedstocks using cell free approaches. These routes will help reduce the current risk and cost associated with classical cell free production. Cell free technologies show promise for application to the production of toxic/inhibitory products or products difficult to separate from microbial growth media and can help reduce the production barriers in multiple areas of biological conversion of feedstocks to biochemicals. More specifically, we are developing new technologies and routes that could be used to produce high value biochemicals such as 2,3 BDO and terpenes (among many others) from biomass derived C5/C6 sugars or lignin but also from waste byproducts such as glycerol. This project will lead to significant innovation and also lead to new concepts and rational design of pathways and enzymes. Within this project, we will develop new metabolic enzyme cascades that will represent natural or artificial combinations of enzymes to produce the desired biochemicals from a variety of feedstocks. We are also developing basic design principals for constructing synthetic metabolons, using fusion proteins and synthetic protein scaffolds, to promote substrate channeling and stability while conserving peak activity. Additionally, our efforts include a techno economic analysis (TEA) of cell free approaches to provide the sensitivities of the process to enzyme loading, activity, pH, reactor volumes, cofactor recycling rates. Finally, we are focusing on further increasing stability, operating lifetime and efficiency of the pathway enzymes by immobilization on support surfaces. We are also focus on immobilizing pathway enzymes or combinations of enzymes on several different conducting polymers and evaluate the effect on stability and operating lifetime. As more combinations become available we will conduct a more systematic study of the means of immobilizing these enzymes. This preliminary work will enable the in-depth study of cofactor recycling at these interfaces using mediators for electron transfer. Taken together, these approaches will enable process intensification, continuous operation, lower capital and separations costs and end-product flexibility, and thus has the potential to contribute significantly to BETO's goals of cost competitive biofuels and bioproducts. To date we have demonstrated 1) the conversion of pyruvate to 2,3 BDO (4 enzymes with cofactor recycling, no additional cofactors needed) at >100g/L (>3g/L/h) using our enzyme tethering approach, 2) Generated mutants of a key redox enzyme with >180- fold improvement in NADH utilization over WT to >85% of NADPH utilization. 3) Produced mevalonate at >10g/L from glucose, limonene at >10g/L from mevalonate and more than >5g/L from glucose with crude enzyme preparations and complete cofactor recycling. 4) successfully generated fully active cross-linked aggregates (CLEAs) of NOX, a cofactor-regenerating water-forming oxidase that is key to our process with increased stability 5) Engineered and identified enzymes able to use the biomimetic cofactor NMN and synthesized new synthetic cofactors.

biocatalysis↗