85 results about "Nitrogenase" patented technology

Disclosed herein are methods, compositions, and kits for determining the presence or absence of a target polypeptide (e.g., a polypeptide involved in nitrogen fixation) in a sample (e.g., a sample of soil from the rhizosphere of a non-leguminous plant).

The invention discloses a pseudomonas for antimony detoxification and autotrophic nitrogen fixation and application of the pseudomonas. The strain is separated from the rhizosphere of a pioneer plant in antimony-polluted soil of a tin mine in cold water river city, Hunan province, and is identified to be capable of quickly oxidizing high-toxicity antimony (III) into low-toxicity antimony (V) through autotrophic metabolism in a high-antimony environment, so that antimony detoxification is realized, and the detoxification rate is 108.6 (mu mol / (L.day)). The strain has autotrophic nitrogen fixation activity and can achieve autotrophic growth under the oligotrophic condition of a mining area, and the nitrogenase activity is larger than or equal to 223.4 (nmol C2H2 / (g.h)). Particularly, the antimony detoxification and nitrogen fixation capabilities of the strain have a synergistic effect, so that the strain has unique advantages in the field of heavy metal antimony pollution remediation, and dual effects of antimony pollution treatment and soil improvement can be synchronously realized; the development and application prospects are good.

The invention discloses an autotrophic nitrogen fixation Klebsiella strain with antimony oxidation and growth promoting capabilities and application thereof. The strain is different from traditional heterotrophic nitrogen-fixing bacteria depending on an organic carbon source, nitrogen fixation can be carried out by taking carbon dioxide as a main carbon source under an oligotrophic condition, Sb (III) oxidation is taken as a main energy acquisition way, autotrophic metabolism is realized, and plant growth can also be promoted. Through identification, Sb (III) can be oxidized into Sb (V) in three days in a high-antimony environment, and the oxidation rate reaches 89.11 (mu mol / L / day); the activity of nitrogenase is greater than or equal to 167.4 (nmolC2H2 / (g.h)). The strain has unique advantages in the field of in-situ remediation of antimony-polluted tailings and other oligotrophic matrixes, and can synchronously realize multiple effects of antimony pollution treatment, soil nitrogen supply and quality improvement. The strain is safe to human and livestock, has no environmental pollution problem, is simple in culture condition and easy to preserve, and has good development and application prospects.

According to the high-temperature-resistant nitrogen-fixing bacteria microcapsule fertilizer and the preparation method thereof, aiming at the problems of thallus inactivation and nutrient loss in a high-temperature environment, a sodium alginate-chitosan double-layer embedding technology is combined with magnetic nanoparticle modification, and a stable double-layer structure is formed by optimizing the ratio of an embedding material, so that the high-temperature-resistant nitrogen-fixing bacteria microcapsule fertilizer is prepared. The survival rate and activity of the nitrogen-fixing bacteria at high temperature are remarkably improved, and meanwhile, the functions of intelligent nutrient release and magnetic recovery are achieved. The fertilizer is prepared from composite microcapsules, amino acid, humic acid and other raw materials according to a specific ratio through magnetic field orientation treatment, multi-stage mixing, atomization granulation and magnetic field screening processes, the particle size is controlled to be 0.5-3.35 mm, and the shelf life is prolonged to 12 months. The method has the technical effects that trehalose-glycerol / sorbitol synergistically forms a glassy protective film to maintain the stability of thalli, gamma-aminobutyric acid activates nitrogenase gene expression, magnetic nanoparticles construct a photosynthetic symbiotic system to optimize rhizosphere oxygen supply, and silanized FeO nanoparticles fix heavy metal ions through electrostatic adsorption, so that the heavy metal ions in the thalli are effectively adsorbed, and the heavy metal ions in the thalli are effectively adsorbed. And the humic acid buffers the pH fluctuation of the soil, so that the nitrogen fixation efficiency is finally improved by 30-50%, and the crop yield is increased by 15-25%.

The invention discloses a microbial fertilizer and a preparation method and application thereof.The microbial fertilizer comprises a biochar carrier and non-symbiotic nitrogen-fixing bacteria attached to the biochar carrier, and the non-symbiotic nitrogen-fixing bacteria are Klebsiella pneumoniae sp. The straw biochar has the advantage that the effect of improving the activity of nitrogenase is more remarkable according to the particle size of 0.25-2 mm. The biochar with the particle size of 0.25-2mm provides a good habitat for strain cells and can better preserve water and fertilizer, so that growth and reproduction of strains are guaranteed, and the biochar can be put into soil for use. The loading effect of the corn straw biochar is superior to that of wood biochar, the C: N value of the corn straw biochar is remarkably lower and ranges from 61 to 84, and growth of nitrogen-fixing bacteria is facilitated. The content of total nitrogen and microbial biomass nitrogen in soil is effectively improved, and the corn stalk carbon has a more obvious effect on increasing the microbial biomass nitrogen in the soil and is closely related to the activity of soil microorganisms.

The invention discloses an application of paenibacillus polymyxa in improving the yield of pyrroloquinoline quinone, and relates to an application of hyphomicrobium in improving the nitrogen fixation capability of the paenibacillus polymyxa. The invention also discloses a co-culture system with high pyrroloquinoline quinone yield. The invention further discloses the hyphomicrobium, and the preservation number of the hyphomicrobium is CCTCC (China Center For Type Culture Collection) NO: M 20241604. The invention further discloses the paenibacillus polymyxa, and the preservation number of the paenibacillus polymyxa is CCTCC (China Center for Type Culture Collection) NO: M 20241603. The invention also discloses a fermentation broth prepared by using the co-culture system. The invention further discloses application of the co-culture system and the fermentation liquor. The paenibacillus polymyxa and the hyphomicrobe are co-cultured and fermented, so that the yield of PQQ produced by the hyphomicrobe can be bidirectionally promoted at the same time, and the nitrogenase activity of the paenibacillus polymyxa can be improved; the co-culture fermentation broth can improve nitrogen fixation, stress resistance, growth and yield of crops.

The invention discloses bacillus safensis and application thereof to synergistically promoting soybean root nodule formation and yield increase with pseudomonas, the bacillus safensis is preserved in China General Microbiological Culture Collection Center (CGMCC), the preservation number is CGMCC No.34634, the preservation date is May 22, 2025, the preservation number is CGMCC No.34634, the preservation number is CGMCC No.34634, the preservation number is CGMCC No.34634, and the preservation number is CGMCC No.34634. The preservation address is Institute of Microbiology, Chinese Academy of Sciences, No.3, Yard 1, Beichen West Road, Chaoyang District, Beijing. According to the method disclosed by the invention, the increase of nodules and the increase of nitrogenase activity can be promoted by co-inoculating the bacillus safensis and the pseudomonas, and meanwhile, the increase of the yield of a biological membrane is also promoted by co-inoculating.

The invention provides application of GmEDS5a and / or GmEDS5b genes in regulation and control of soybean root nodule size and soybean nitrogenase activity or in soybean breeding, and belongs to the technical field of gene engineering. The GmEDS5a and / or GmEDS5b genes are / is knocked out, the proportion of root nodules with the particle size larger than 2 mm is increased, the soybean nitrogenase activity is remarkably improved, symbiotic nitrogen fixation is promoted, and great significance is achieved for increasing the soybean yield.

The invention discloses a natural nitrogenase-like FeMo nano-enzyme and a preparation method and application thereof, and relates to the technical field of nano-enzymes and agriculture, the method comprises the following steps: respectively dissolving 1, 3, 4-thiadiazole-2, 5-diamine, molybdenum pentachloride, ferric chloride and 2, 5-thiophenedicarboxylic acid in absolute ethyl alcohol; the preparation method comprises the following steps: adding a molybdenum pentachloride solution and a ferric chloride solution into a 1, 3, 4-thiadiazole-2, 5-diamine solution, and stirring until the solution is yellowish-brown to obtain a FeMo nano-enzyme mixed solution; and adding a 2, 5-thiophenedicarboxylic acid solution into the FeMo nano-enzyme mixed solution, stirring, and sequentially centrifuging, drying and calcining to obtain the natural nitrogenase-like FeMo nano-enzyme. The FeMo nano-enzyme has nitrogen fixation activity similar to that of natural nitrogenase, nitrogen and water can generate ammonia at normal temperature and normal pressure, and the technical problem that in-situ generation of ammonia in plants at normal temperature and normal pressure is difficult in the prior art is solved.

The invention relates to the field of growth-promoting bacteria, in particular to screening and application of saline-alkali soil crop growth-promoting bacteria, and discloses a screening method and application of the saline-alkali soil crop growth-promoting bacteria. Through gradient domestication, multi-index function verification and molecular identification, a strain which is salt-tolerant, can efficiently solubilize phosphorus (more than 150 mu g / mL), can secrete IAA (more than 30 mg / L) and has nitrogenase activity more than 20 IU / L is screened from rhizosphere soil with salt concentration of 0.8%-1.2% and pH of 7.8-8.5. Screened strains are compounded with a carrier (the ratio of decomposed sheep manure to attapulgite to humic acid to xanthine is (70-75): (20-25): (8-10): (0.3-1)), the complex microbial inoculant is prepared through secondary fermentation, and a final field test shows that the yield of corn can be increased by 18%-32%, the pH of soil is reduced by 0.5-1.0, the salinity is reduced by 0.2%-0.5%, the saline-alkaline environment is remarkably improved, and the complex microbial inoculant has a wide application prospect.

Heterologous synthesis of a nitrogen-fixing system in a non-diazotrophic organism is a long-sought-after goal because of the significance of nitrogenase for areas related to agronomy, energy and environment. Two simplified nitrogenase analogs from Azotobacter vinelandii in Escherichia coli were successfully heterologously synthesized. One analog comprise the reductase component (NifH) and, in place of the catalytic component (NifDK), a cofactor maturase (NifEN); whereas the other analog comprised only NifEN. Metal, EPR and activity analyses verified the cluster composition and functional competence of the heterologously expressed NifH and NifEN. Moreover, NMR, nanoSIMS and growth experiments illustrated the abilities of both systems to mimic the nitrogenase in reducing N2 and incorporating the reduced N into the cellular mass. These results firmly established NifEN / NifH or NifEN as a simplified nitrogenase analog that could be engineered or expanded to facilitate future transgenic expression of nitrogenase and development of nitrogenase-based biotechnological applications.

The invention discloses a gene GmSCAMP3 for regulating and controlling the symbiotic nitrogen fixation capacity of soybean root nodules and application of the gene GmSCAMP3. Specifically, the invention provides a protein for regulating and controlling the symbiotic nitrogen fixation capacity of soybean root nodules, and the amino acid sequence of the protein is as shown in SEQ ID NO: 2. The invention also provides a method for improving soybean yield or changing soybean root nodule symbiotic nitrogen fixation capacity. The method comprises the step of introducing the polynucleotide encoding the protein into soybean cells or tissues to obtain transgenic soybeans. The invention finds that the nitrogenase activity of the Gmscamp3 mutant root nodule is only 65.79% of that of a wild type root nodule, which indicates that the GmSCAMP3 protein plays an important role in the process of regulating and controlling the symbiotic nitrogen fixation capacity of the soybean root nodule.

The invention relates to a recombinant engineering bacterium for expressing pure iron nitrogenase as well as a construction method and application of the recombinant engineering bacterium, and belongs to the field of biotechnology and bioengineering. Key gene clusters of rhodopseudomonas and Vilnelande nitrogen-fixing bacteria are amplified and cloned into an expression vector, escherichia coli is converted to obtain recombinant engineering bacteria for expressing pure iron nitrogenase, and the pure iron nitrogenase expressed by the recombinant engineering bacteria can reduce carbon dioxide (CO2) into methane (CH4); the recombinant engineering bacteria are cultured in an LB culture medium added with ferric chloride, ampicillin and spectinomycin, oxygen exposure is reduced as much as possible under the optimized semi-anaerobic condition, the enzyme activity can be improved to the maximum extent, and compared with a traditional system, the methane yield is remarkably increased; by providing a novel methane production scheme, the technical defects of low efficiency and oxygen sensitivity of the traditional nitrogenase process are improved; the process of the present invention contributes to carbon capture and utilization by converting waste carbon dioxide into valuable methane.

The invention relates to the technical field of biology, and discloses application of PHR2 in regulating nodulation and nitrogen fixation processes of leguminous plants under phosphorus starvation stress, and the application is any one of the following applications: P1, application in enhancing nitrogen fixation capability of the leguminous plants under the phosphorus starvation stress; p2, application in promoting formation of root nodules with nitrogen fixation capacity of leguminous plants under phosphorus starvation stress; p3, application of improving activity of nitrogenase in leguminous plant root nodules under phosphorus starvation stress; p4, application in leguminous plant breeding. The PHR2 protein and related biological materials thereof can be used for regulating and controlling the nitrogen fixation capacity of leguminous plants under phosphorus starvation stress.

The invention relates to an artificial efficient nitrogen fixation system and a preparation method and application thereof. The artificial efficient nitrogen fixation system contains recombinant engineering bacteria constructed by an artificial combination module and nitrogen fixation chassis microorganisms; wherein the artificial combination module sequentially comprises a constitutive promoter element Pc and a coding gene of methyltransferase selected from nitrogen-fixing pseudomonas stutzeri A1501 in the direction from upstream to downstream. According to the recombinant engineering bacteria constructed by introducing the artificial combination module into the nitrogen-fixing chassis microorganism, the nitrogenase activity of the nitrogen-fixing chassis microorganism can be remarkably improved, the nitrogen-fixing capacity of the nitrogen-fixing chassis microorganism is remarkably improved, and the recombinant engineering bacteria have a relatively good application prospect in the aspect of promoting plant growth.

The invention belongs to the technical field of soil improvement, and particularly relates to stenotrophomonas maltophilia C-GD and application thereof in nitrogen fixation. The nitrogenase activity of the stenotrophomonas maltophilia C-GD is 45.90 (ng / g / 24h), and the stenotrophomonas maltophilia C-GD shows relatively good nitrogen fixation activity and can be used for nitrogen fixation of soil. The invention provides a strain of Stenotrophomonas maltophilia C-GD with a nitrogen fixation function, and after the Stenotrophomonas maltophilia C-GD is prepared into a microbial inoculum to be applied, the key nutrient indexes of organic matters, total nitrogen, total phosphorus, available phosphorus, alkali-hydrolyzable nitrogen and the like in soil can be greatly improved.

The invention belongs to the technical field of microbial protein production, and particularly relates to a method for improving the yield of microbial protein functional bacteria. The method comprises the following steps that enriched nitrogen-fixing gas hydrogen-oxidizing bacteria and an ammonium-free culture medium are mixed and then inoculated into a bioreactor, a gas supply strategy is dynamically adjusted in a multi-stage mode according to biomass changes, the biomass is expressed by OD600, and the method specifically comprises the following processes that when OD600 is smaller than a preset value, a first-stage gas supply method is adopted; when OD600 changes to a preset value, the gas supply mode is adjusted from the first stage to the next stage; the proportion of oxygen in the gas supply method in the first stage is lower than that in the gas supply method in the later stage. When the biomass is low, inhibition of oxygen on nitrogenase is relieved by properly reducing the proportion of oxygen, the delay period of the earlier culture period is shortened, oxygen is supplemented in time after the biomass is increased, sufficient electron and energy supply is guaranteed, high-speed growth in the rapid growth period is maintained, and efficient growth of nitrogen-fixing hydrogen oxidizing bacteria is achieved.

The invention discloses application of a GmNSE1 gene in regulation and control of soybean root nodule nitrogen fixation efficiency. The application of the GmNSE1 gene or a biological material related to the GmNSE1 gene in at least one of the following aspects: A1) regulating and controlling the nitrogen fixation efficiency of soybean root nodules or preparing a product for regulating and controlling the nitrogen fixation efficiency of the soybean root nodules; a2) cultivating soybeans with improved nitrogen fixation efficiency or preparing products for improving the nitrogen fixation efficiency of the soybeans; a3) preparing transgenic soybeans; the nucleotide sequence of the GmNSE1 gene is as shown in SEQ ID NO. 1. The specificity of the GmNSE1 gene is expressed in a root nodule infection area, the GmNSE1 gene has E3 ubiquitin ligase enzyme activity in vitro, and compared with a control group, the nitrogenase activity of a soybean plant with the overexpressed GmNSE1 gene is remarkably improved, which shows that the GmNSE1 gene plays an important role in the process of regulating and controlling the symbiotic nitrogen fixation capacity of soybean root nodules, and the GmNSE1 gene has a good application prospect in the field of soybean root nodule symbiotic nitrogen fixation. The method has application prospects in research on nitrogen fixation mechanisms of leguminous crops and agricultural production.

The invention relates to the technical field of microorganisms, and provides a rhizobium mutant and application thereof, the rhizobium mutant is HH103 delta nuo, and is a mutant obtained by taking sinorhizobium fredii (sinorhizobium fredii) HH103 as a starting strain and performing gene knockout on a nuo control unit in an NADH oxidoreductase subunit I of the sinorhizobium fredii HH103. When the HH103 delta nuo is inoculated in the soybean seedling stage, the plant shows that the leaves are darker green, the plant biomass is up-regulated, the nitrogenase activity of a single plant is obviously higher than that of a wild type strain, and the plant height is integrally increased, so that the HH103 delta nuo improves the symbiotic effect of the rhizobium and the soybean.

The invention relates to an efficient gene transcription activation system and application thereof. The system comprises a positive regulatory gene, a DNA sequence which is located at the upstream of the positive regulatory gene and is combined with a positive regulatory protein expressed by the positive regulatory gene, and a corresponding promoter of the DNA sequence. According to the system, a UAS sequence combined with a positive regulatory protein expressed by a positive regulatory gene and a corresponding promoter are utilized to express the positive regulatory gene, the just synthesized positive regulatory protein can be immediately combined to an upstream UAS sequence, and the positive regulatory protein interacts with a sigma 54 factor to stimulate the expression of the downstream positive regulatory gene of the corresponding promoter, so that more positive regulatory proteins are synthesized, and the positive regulatory protein is expressed by the corresponding promoter. A positive feedback transcriptional regulation expression cycle is formed. The invention provides a gene transcription activation system taking the nifA gene as a positive regulation gene, so that the enzyme activity of nitrogenase and the yield of indole-3-acetic acid and prodigiosin are effectively improved. The invention further provides a gene transcription activation system taking the slnR gene as a positive regulation gene, and the salinomycin yield is effectively improved.

The invention discloses application of a GmNSE1 gene in regulation and control of soybean root nodule nitrogen fixation efficiency. The application of the GmNSE1 gene or a biological material related to the GmNSE1 gene in at least one of the following aspects: A1) regulating and controlling the nitrogen fixation efficiency of soybean root nodules or preparing a product for regulating and controlling the nitrogen fixation efficiency of the soybean root nodules; a2) cultivating soybeans with improved nitrogen fixation efficiency or preparing products for improving the nitrogen fixation efficiency of the soybeans; a3) preparing transgenic soybeans; the nucleotide sequence of the GmNSE1 gene is as shown in SEQ ID NO. 1. The specificity of the GmNSE1 gene is expressed in a root nodule infection area, the GmNSE1 gene has E3 ubiquitin ligase enzyme activity in vitro, and the activity of a mutant with the GmNSE1 gene knocked out is remarkably reduced compared with that of wild nitrogenase, so that the GmNSE1 gene plays an important role in the process of regulating and controlling the symbiotic nitrogen fixation capacity of soybean root nodules; the method has application prospects in research on nitrogen fixation mechanisms of leguminous crops and agricultural production.

The invention provides application of hydroxypropyl chitosan oligosaccharide in preparation of a plant growth regulator, and belongs to the technical field of plant growth. The hydroxypropyl chitosan oligosaccharide is used as a raw material to prepare the plant growth regulator, new application of the hydroxypropyl chitosan oligosaccharide is provided, the seedling height of plants can be effectively increased, the root length can be effectively increased, the number and / or weight of root nodules can be effectively increased, the number of the root nodules of the plants and / or the activity of nitrogenase can be effectively increased, and the yield of the plants is increased. According to the present invention, the activity of glutathione reductase (GR) and / or glutathione transferase (GST) is improved so as to increase the reduced glutathione content, enhance the oxidation resistance of plants and / or enhance the salt resistance of crops, and after the compound fertilizer is compounded with the calcium-magnesium element fertilizer, the use amount of the compound fertilizer is reduced so as to provide effects of application reducing and effect increasing. The method for preparing the plant growth regulator is simple and easy to implement, environmentally friendly and convenient to popularize and apply.

The invention discloses ammonium-tolerant nitrogen-fixing paenibacillus and application thereof, and belongs to the technical field of agriculture. The bacterial strain is preserved in Guangdong Microbial Culture Collection Center on September 19, 2025, the preservation number is GDMCC 66998, and the bacterial strain is named Paenibacillus sp. By taxonomy. The ammonium-tolerant nitrogen-fixing paenibacillus from the red soil rice field is obtained through screening, the strain still shows high nitrogenase activity under the condition of 80-100 mM NH4 < + >, and the limitation that traditional nitrogen-fixing bacteria are prone to being inhibited by ammonium is broken through. In addition, the strain can significantly improve the germination rate of rice seeds, promote the root length, plant height and biomass accumulation of rice seedlings, and show a good growth promotion effect. Due to the characteristic of forming spores, the strain can also be prepared into a microbial fertilizer preparation which is used for nitrogen fertilizer replacement and synergism in a rice field ecological system.

The invention provides a NifA protein mutant and application thereof, the NifA protein mutant comprises mutation based on a reference sequence, the amino acid sequence of the reference sequence is as shown in SEQ ID NO: 1, and the amino acid of the NifA protein mutant comprises: (1) amino acid mutation corresponding to at least one site in R194 and R198 of the SEQ ID NO: 1, preferably amino acid mutation corresponding to the R194 and R198 of the SEQ ID NO: 1; (2) an amino acid mutation corresponding to at least one site in the 182-VNEED-186 of SEQ ID NO: 1, preferably an amino acid mutation corresponding to the 182-VNEED-186 site of SEQ ID NO: 1; or (3) N-terminal amino acid truncation corresponding to SEQ ID NO: 1, preferably amino acid deletion corresponding to the first 209 sites of SEQ ID NO: 1. The NifA protein mutant disclosed by the invention has the characteristic of immortality, can enhance the expression of nitrogenase genes, has a good application prospect in the aspects of improving the nitrogen fixation efficiency of nitrogen-fixing bacteria, developing green and efficient biological fertilizers and the like, and promotes the development of a biological nitrogen fixation technology to a certain extent.

The invention discloses a microbial agent composition capable of promoting growth and yield increase of soybeans in saline soil and application of the microbial agent composition. A microbial agent is an enterobacter strain THD10 or a complex microbial agent formed by the enterobacter strain THD10. The microbial agent provided by the invention can significantly improve the plant height, fresh weight, dry weight, nodulation number and nitrogenase activity of soybeans. In saline soil, compared with treatment without inoculation of the microbial inoculum, inoculation treatment can significantly improve the soybean biomass, and the nitrogen fixation efficiency of a single soybean plant is improved; the SOD, CAT and POD contents of soybean leaves are increased, and the malondialdehyde content of the leaves is reduced; the method can improve the soybean yield and promote the improvement of soybean quality indexes, has very important significance for enlarging the soybean cultivation area and improving the per unit yield in China, and has important guidance and reference significance for cultivation of other crops in saline soil.

The invention relates to a method for promoting growth, nodulation and nitrogen fixation of indigofera pseudotinctoria by utilizing rhizobium D303 and a bacterial solution thereof. The biological preservation number of the rhizobium sp. D303 is CCTCC (China Center for Type Culture Collection) NO: M20252803. Pot culture tie-back tests prove that the indigofera pseudotinctoria seedlings inoculated with the rhizobium are obviously superior to a control group in the aspects of plant height, root length, overground dry weight, underground dry weight, root nodule number, root nodule weight, root nodule diameter, nitrogenase activity, antioxidant enzyme activity and the like. The rhizobium strain provided by the invention has efficient nodulation and nitrogen fixation capability and excellent growth promoting characteristic, obviously improves the growth speed, nodulation capability and nitrogen fixation efficiency of the indigofera pseudotinctoria, reduces the dependence on chemical nitrogen fertilizer, and has a broad application prospect in development of special biological bacterial fertilizer for indigofera pseudotinctoria. The method has important ecological and economic benefits for promoting the application of the indigofera pseudotinctoria in ecological restoration and feed production, and is suitable for slope greening, water and soil conservation and barren mountain ecological restoration projects.

The invention discloses an oxygen-resistant photosynthetic nitrogen-fixing engineering bacterium as well as a construction method and application thereof. The oxygen-resistant photosynthetic nitrogen fixation engineering bacterium disclosed by the invention does not contain a fixL gene and a fixJ gene. The photosynthetic nitrogen-fixing engineering bacteria disclosed by the invention can be used for nitrogen-fixing growth under an aerobic condition. The obtained photosynthetic nitrogen-fixing engineering bacterium breaks through the limitation that oxygen inhibits nitrogenase expression, nitrogen fixation under the aerobic condition is achieved, the nitrogen-fixing efficiency and nitrogen-fixing stability of photosynthetic microorganisms are improved, a theoretical basis is provided for developing rhodopseudomonas palustris as an efficient photosynthetic nitrogen-fixing microbial agent and expanding application of rhodopseudomonas palustris in the fields of industry and agriculture, and the photosynthetic nitrogen-fixing engineering bacterium has a wide application prospect. Good application prospects are realized.

The invention relates to novel paenibacillus with biomacromolecule degradation capacity and nitrogen fixation and phosphorus solubilization effects and application of the novel paenibacillus, the strain is identified as a novel strain of paenibacillus through multi-phase classification, and the novel paenibacillus has the capacity of degrading biomacromolecules such as starch, cellulose, casein, chitin and lecithin. The method can be applied to degradation of related carbohydrates, proteins and lipid substances and preparation of biological enzymes; the bacillus subtilis has the advantages that the bacillus subtilis can be used for preparing the bacillus subtilis, has the phosphorus dissolving capacity of dissolving organic phosphorus and inorganic phosphorus, has nitrogenase and beta-1, 3-glucanase and the activity of generating IAA (Indoleacetic Acid), can play a probiotic role on crops by fixing nitrogen, dissolving phosphorus and inhibiting pathogenic bacteria, can grow in an environment with the salinity not higher than 4.5%, and has certain salt-tolerant activity. Due to multiple functions, the strain can be used for preparing and applying biological nitrogen fertilizers, phosphate fertilizers and crop probiotics, so that the strain plays an important role in crop growth and green agricultural production.

The invention belongs to the technical field of soil nitrogen fixation and environmental protection, and relates to a method for enhancing soil nitrogen fixation by using pure iron powder. A method for enhancing soil nitrogen fixation by using pure iron powder comprises the following steps: mixing rice soil and wheat straw powder to obtain a soil sample; the method comprises the following steps: mixing a soil sample with pure iron powder under a waterflooding condition; pure iron powder is added to regulate and control microbial ecology of rice soil biological nitrogen fixation, the soil iron reduction process is enhanced, the abundance of iron reducing bacteria in soil is improved, the relative contribution of iron reducing bacteria nitrogen fixation is enhanced to a certain extent, the diversity of iron reducing bacteria communities is reduced, the ecological niches of dominant groups are enhanced, and the ecological niches of the dominant groups are increased. Finally, the nitrogenase activity of the soil is enhanced, and the nitrogen fixation capacity of the rice soil is improved.