114 results about "Hydrogenase" patented technology

The invention provides methods and compositions for engineering microbes to generate Hydrogen. Some methods of the invention involve recoding of hydrogenase genes followed by subjecting the recoded genes to annealing-based recombination methods. The invention further provides methods of mating organisms that are transformed with recoded and recombined hydrogenase genes with other organisms containing different genome sequences.

A process for the production of hydrogen, comprising the steps of: (i) providing a photosynthetic microorganism having electron transfer capability through a photosynthetic “light” reaction pathway and through a respiratory electron transfer chain involving an oxidative phosphorylation pathway, and which expresses a hydrogenase, wherein regulation of the oxidative phosphorylation pathway is disrupted with the result that electron flow along the respiratory electron transfer chain toward cytochrome oxidase (complex IV) is reduced; ii) culturing the microorganism under microoxic and illuminated conditions; and (iii) collecting evolved hydrogen.

The invention relates to a microbial fuel cell, in particular to a green algae biological fuel cell generating power on the basis of photosynthesis, which comprises a transparent cathode cell of green algae culture solution and an anode cell containing rich oxygen or oxidant solution, wherein the cathode cell and the anode cell are isolated by a proton exchange membrane; the cathode and anode of the cell are fixed in the cathode cell and the anode cell respectively; the cathode cell is isolated from the air to create an anaerobic environment in the cathode cell, hydrogen-generating green algae is used a system green algae material, an indirect-process hydrogen generation regulating technique is adopted, an electronic transfer mediator is added into the system to enable electrons which aregenerated by photosynthesis to be combined with the electronic mediator through an electron transport chain before reaching hydrogenase, the electronic mediator releases electrons at a cathode electrode, and the electrons are transferred to the anode to combine with protons passing through the proton exchange membrane and oxidant in the cathode cell to form water. In the invention, optical energycan be converted into electric energy by coupling the photosynthesis of microalgae and a cell system, and a novel biological fuel cell is provided.

Enzymatically active hydrogenase is synthesized in a cell-free reaction. The hydrogenases are synthesized in a cell-free reaction comprising a cell extract derived from microbial strains expressing at least one hydrogenase accessory protein. In some embodiments, the extracts are produced under anerobic conditions.

An eka-cecropinA-magainin heterozygous gene engineering antibacterial peptide is prepared by adopting No.1-7 amino acid residue on N end of cecropinA CA and No.2-12 amino acid residue on N end of magainin M, design synthesizing heterozygous peptide CA(1-7)-M(2-12) gene by codon, connecting with carrier pPICZ alpha-A, mutating by point mutation technology to obtain mutant pPICZ alpha-CA-Mu-1, pPICZ alpha-CA-Mu-2 and pPICZ alpha-CA-Mu-3, converting SMD1168, and expressing CecA-Mag heterozygous antibacterial peptide to make into use under alcohol hydrogenase starter regulation.

It is intended to obtain anaerobic microbial cells in an amount sufficient for hydrogen generation reaction, impart a hydrogen generation function to an aerobic microorganism within a short time and provide an industrial advantageous method of producing hydrogen. The above object can be established by providing a highly efficient microbial hydrogen production method characterized by comprising culturing a microorganism having a formate dehydrogenase gene and a hydrogenase gene under aerobic conditions, culturing the resulting microbial cells under anaerobic conditions in a liquid culture medium containing a formic acid compound, and then using the thus obtained cells for hydrogen generation.

A reversible physiological process provides for the temporal separation of oxygen evolution and hydrogen production in a microorganism, which includes the steps of growing a culture of the microorganism in medium under illuminated conditions to accumulate an endogenous substrate, depleting from the medium a nutrient selected from the group consisting of sulfur, iron, and/or manganese, sealing the culture from atmospheric oxygen, incubating the culture in light whereby a rate of light-induced oxygen production is equal to or less than a rate of respiration, and collecting an evolved gas. The process is particularly useful to accomplish a sustained photobiological hydrogen gas production in cultures of microorganisms, such as Chlamydomonas reinhardtii.

The invention discloses a method for improving the fermentation productivity of carotenoid, which is realized by the following steps: rhodotorula mucilaginosa is used as fermentation strains of the carotenoid, and the rhodotorula mucilaginosa is inoculated into a culture medium according to the inoculum size of 2%-10%; a ferrous ion solvent is added into the culture medium, wherein the volume of addition of the ferrous ion solvent is that the molarity relative to the culture medium is between 0.05-0.5mmol/L, and the fermentation temperature is kept at 27-33 DEG C; after the fermentation lasts for 32-40 hours, the temperature is lowered to 20-25 DEG C for continuous fermentation; the fermentation lasts for 24-46 hours. By adding ferrous ions, the capability of beta-carotene for converting into the high antioxygen carotenoid is greatly improved, the insufficience of quantity of beta-carotene dioxygen dismutase and beta-carotene hydrogenase is made up; the beta-carotene is converted into the high antioxygen carotenoid; by the method, the fermentation yield is improved by 30-34%.

The invention relates to nano-iron-loaded biochar, a preparation method of the nano-iron-loaded biochar, and an application of the nano-iron-loaded biochar in a dark fermentation hydrogen production process. Ferrite and soluble starch are taken as raw materials which are subjected to reaction under proper conditions and are dried and charred to obtain the nano-iron-loaded biochar, wherein the maincomponent of the nano-iron-loaded biochar is Fe2O3/C, and the particle diameter range of the nano-iron-loaded biochar is 2-150nm. The biochar is of an amorphous structure, and Fe2O3 is of a mesoporous structure. By adding the iron-loaded biochar to an anaerobic fermentation system, a synergistic strengthening effect of iron and biochar in the dark fermentation hydrogen production process is realized, so that the hydrogen yield and the process stability are improved. Fe2O3 can not only release iron ions to enhance the activity of fermentative hydrogen producing bacterium hydrogenase but also increase the transfer rate of electrons; and furthermore, the biochar in nano-particles can enrich microorganisms, improve the concentration of hydrogen producing bacteria, buffer acid accumulation andrelieve ammonia inhibition.

The present invention provides a method for the biological production of n-butanol at high yield from a fermentable carbon source. In one aspect of the present invention, a process for the conversion of glucose to n-butanol is achieved by the use of a recombinant organism comprising a host C. acetobutilicum transformed i) to eliminate the butyrate pathway ii) to eliminate the acetone pathway iii) to eliminate the lactate pathway and iv) to eliminate the acetate pathway. In another aspect of the present invention, the hydrogen flux is decreased and the reducing power redirected to n-butanol production by attenuating the expression of the hydrogenase gene. Optionally the n-butanol produced can be eliminated during the fermentation by gas striping and further purified by distillation.

The present invention provides a method for the biological production of n-butanol at high yield from a fermentable carbon source. In one aspect of the present invention, a process for the conversion of glucose to n-butanol is achieved by the use of a recombinant organism comprising a host C. acetobutylicum transformed i) to eliminate the acetate pathway ii) to eliminate the butyrate pathway iii) to eliminate the lactate pathway and iv) to eliminate the acetone pathway. In another aspect of the present invention, the hydrogen flux is decreased and the reducing power redirected to n-butanol production by interrupting the expression of the hydrogenase gene. Optionally the n-butanol produced can be eliminated during the fermentation by gas striping and further purified by distillation.

The invention relates to a method for maintaining continuous hydrogen production after chlorella cell death. The invention belongs to the technical field of biology and particularly relates to a method for maintaining continuous hydrogen production after chlorella cell death. The invention aims to introduce a power supply system into the living environment of chlorella, and to realize high-efficiency and continuous hydrogen production in an anaerobic environment by utilizing hydrogenase in the chlorella body. The method comprises the following steps: taking chlorella pyrenoidosa as a basic organism, and constructing an integrated artificial hydrogen production system by using a biological enzyme-hydrogenase in the chlorella body through an external conductive medium pyrrole and an electronsupply system. The method enables the biological enzyme to be efficiently and fully utilized, not only can maintain the activity of life body of chlorella cells, but also can continue to utilize active substances in the body of the chlorella cells after the life body is dead, so that the chlorella pyrenoidosa can continuously and efficiently produce hydrogen in an anaerobic environment for more than two months.

MohC is required for expression of uptake hydrogenase in A. vinelandii and inactivation of this gene results in H₂ evolution via nitrogenase 3. Since MohC⁻ mutants are tungsten tolerant under nitrogen-fixing conditions, tungsten can be used to select spontaneous tungsten-tolerant mutants of nitrogen-fixing bacteria that are genetically uncharacterized. A major advantage of producing H₂ via nitrogenase 3 is that carbon substrates used to culture the nitrogen-fixing bacteria harboring this nitrogenase are derived from plant sources.

The invention discloses an artificial simulation hydrogenase of an aromatic ether dendritic polymer. The artificial simulation hydrogenase has the following two molecular structures of a molecular structure (I) and a molecular structure (II), wherein X is the aromatic ether dendritic polymer and has a structural formula shown in the description, R1, R2, R3 and R4 are carbonyl, isocyano, triphenylphosphino, trimethylphosphino, triethylphosphino, tributylphosphino or tripyzzolephosphino. Compared with natural hydrogenase, the artificial simulation hydrogenase of the aromatic ether dendritic polymer disclosed by the invention has good stability and is convenient to store; the artificial simulation hydrogenase is firstly used as a proton reduction catalyst for hydrogen production by water decomposed under catalysis of visible light; during hydrogen production, the catalyst has a stable property and a rather high hydrogen production catalytic activity; so far, the artificial simulation hydrogenase is an artificially synthesized artificial simulation hydrogenase with a highest catalytic activity.

Compositions of a fusion protein comprising a spatially tethered ferredoxin-NADP-reductase (FNR) and an active [FeFe] hydrogenase, genetic sequences encoding such fusion proteins, and methods of use thereof are provided. The fusion proteins of the invention link an FNR polypeptide to an active [FeFe] hydrogenase through a polypeptide linker. The fusion protein facilitates improved electron transfer through a ferredoxin, and allows direct electron transfer from NADPH to the hydrogenase.

The invention relates to a micro-organism comprising a hydrogenase enzyme system which is capable of converting carbon dioxide into formic acid and a second enzyme system which is capable of converting formic acid into aliphatic carboxylic acids having a chain length of five or more carbon atoms. Also described are various methods for producing oil, as well as other aspects of the invention.

In situ fluorescence method to monitor state of sulfur-deprived algal culture's ability to produce H₂ under sulfur depletion, comprising: a) providing sulfur-deprived algal culture; b) illuminating culture; c) measuring onset of H₂ percentage in produced gas phase at multiple times to ascertain point immediately after anerobiosis to obtain H₂ data as function of time; and d) determining any abrupt change in three in situ fluorescence parameters; i) increase in F_t (steady-state level of chlorophyll fluorescence in light adapted cells); ii) decrease in F_m, (maximal saturating light induced fluorescence level in light adapted cells); and iii) decrease in ΔF/F_m′=(F_m′−F_t)/F_m′ (calculated photochemical activity of photosystem II (PSII) signaling full reduction of plastoquinone pool between PSII and PSI, which indicates start of anaerobic conditions that induces synthesis of hydrogenase enzyme for subsequent H₂ production that signal oxidation of plastoquinone pool asmain factor to regulate H₂ under sulfur depletion.

The invention discloses rhodobacter capsulatus and an application thereof. The invention provides rhodobacter capsulatus BN-W-6 which has a collection number of CGMCC No.8311 and belongs to photosynthetic bacteria. The rhodobacter capsulatus is fermented by adding an energy source after enlargement cultivation to obtain fermentation products including chlorophyll a, carotenoid, ketone-carotenoid, hydrogenase, catalase and the like. Biological enzymes generated by the fermentation products of the rhodobacter capsulatus in a pond can ensure that macroscopic algae are gradually decomposed, the products including chlorophyll a, carotenoid and the like can absorb illumination wavebands necessary for growth of the macroscopic algae to make the macroscopic algae shrunk and agglomerated until death, and the dead macroscopic algae can not influence bottom matters, thereby achieving the aims of controlling rampant growth of algae and not influencing the normal growth of sea cucumbers. The fermentation broth of the rhodobacter capsulatus provided by the invention can be used for inhibiting and removing the macroscopic algae, so that the culture density is increased, the culture environment is improved, and the aim of improving the pond culture output of aquatic organisms is achieved.

The invention provides a [ferronickel]hydrogenase model compound containing dppf skeleton and O-alkyldithiophosphate ligand. The [ferronickel]hydrogenase model compound is a bimetallic complex formed by connection of 1, 1'-bis(diphenylphosphine)ferrocene (dppf) structural unit and the O-alkyldithiophosphate ligand with metal nickel atom, and has a chemical structure shown as the specification, wherein R can be methyl, ethyl, benzyl or phenethyl. The synthesis method provided by the invention has the advantages of simple operation, mild reaction conditions, simple post-treatment and high yield, etc., is suitable for synthesis of a variety of [ferronickel]hydrogenase model compounds containing 1, 1'-bis(dialkylphosphine)ferrocene skeleton and O-alkyldithiophosphate ligand, and the model compounds have good catalytic hydrogen production performance, thus having potential industrial application value.