3781 results about "Engineered genetic" patented technology

The invention belongs to the technical field of gene engineering and enzyme engineering, and particularly relates to an ornithine decarboxylase mutant as well as a coding gene, an expression vector, a recombinant strain and application thereof. The ornithine decarboxylase mutant is obtained by mutating wild ornithine decarboxylase ODC10 of which the amino acid sequence is shown as SEQ ID NO.1, the catalytic activity of the obtained mutant is improved, and the biosynthesis efficiency of 1, 4-butanediamine is favorably improved. The recombinant strain for expressing the ornithine decarboxylase mutant constructed by the invention can efficiently synthesize 1, 4-butanediamine, and the molar conversion rate of ornithine is remarkably improved, so that the production benefit is improved, and the production cost is reduced.

The invention provides a genetically engineered bacterium, a preparation method thereof and application of the genetically engineered bacterium in synthesis of sclareol. The genetically engineered bacterium comprises a CcLPPS gene derived from Cistanus crenatus, and a CcLPPS gene derived from Cistanus crenatus, the genetically engineered bacterium is selected from yarrowia lipolytica. According to the invention, the stably expressed sclareol efficient de novo synthesis strain is constructed, and no organic reagent or any path intermediate substance is added in the whole fermentation process, so that the production cost is greatly reduced, and the subsequent separation and purification steps are simplified. The engineering yarrowia lipolytica strain provided by the invention is high in production intensity and simple in fermentation process, has a relatively good application prospect, and lays a foundation for producing sclareol by a microbial fermentation method.

The invention discloses a recombinant humanized XVII type collagen as well as an expression vector and a genetically engineered bacterium thereof. Four functional fragments with high activity are obtained through screening, one of the fragments is optimized and then combined according to a certain sequence to obtain recombinant humanized XVII type collagen JYC1703, or one of the fragments is optimized and then combined according to a certain sequence, and GPP sequences are fused at an amino terminal and a carboxyl terminal respectively to obtain recombinant humanized XVII type collagen JYC1701 and JYC1702, and the recombinant humanized XVII type collagen JYC1701 and JYC1702 are combined according to a certain sequence to obtain the recombinant humanized XVII type collagen JYC1701 and JYC1702. After codon optimization, amplifying and cloning into an expression vector, transforming into pichia pastoris competent cells after enzyme digestion linearization, and screening high-copy recombinants through G418 resistance gradient, so as to obtain pichia pastoris genetically engineered bacteria for expressing recombinant humanized XVII type collagen. The recombinant humanized XVII type collagen JYC1701, JYC1702 and JYC1703 disclosed by the invention show excellent functions of promoting cell adhesion, cell proliferation and cell migration, and are suitable for preparing products such as skin care products or medical instruments and the like.

According to the D-psicose 3-epimerase mutant and the application thereof, the D-psicose 3-epimerase mutant is obtained through protein C-terminal sequence modification, software analysis and sequence alignment of different sources of D-psicose 3-epimerase, the half-life period of the mutant enzyme at 60 DEG C, 70 DEG C and 80 DEG C is prolonged, and the activity of the mutant enzyme is improved. The substrate affinity and conversion efficiency of the enzyme to D-fructose as a substrate for synthesizing D-psicose are improved, and the Tm value of the mutant is 73.23 DEG C and is improved by 11.98 DEG C compared with that of a wild type; the half-life period at the temperature of 60 DEG C is 255.35 min and is 17.60 times that of a wild type, the problem that the half-life period of the wild type is too short at the high temperature is solved, the relative action time of the mutant enzyme is long, the yield of the product D-psicose is remarkably increased by applying the genetically engineered bacterium containing the modified enzyme for biotransformation, the product yield is increased by 4.3%, the equilibrium conversion rate reaches 33%, and the yield of the product is greatly increased. And a green, environment-friendly, sanitary and safe biological preparation method is provided for the preparation process of the D-psicose.

The invention belongs to the technical field of biology, and particularly provides UCRT X heat-resistant reverse transcriptase mutants with improved thermal stability, the UCRT heat-resistant reverse transcriptase mutants provided by the invention comprise four single-point mutants, six double mutants and four three mutants, and compared with wild-type UCRT X heat-resistant reverse transcriptase, the mutant has longer half-life period at 65 DEG C; the double mutant has a better effect, and the half-life period of the double mutant is about four times of that of wild type DNA polymerase. The invention also provides a genetically engineered bacterium containing the mutant. The UCRT heat-resistant reverse transcriptase mutant obtained by the construction method provided by the invention has better thermal stability, shows higher thermal stability when being used for synthesizing DNA (Deoxyribonucleic Acid) by reverse transcription at higher temperature, and has higher application potential.

The present invention relates to the construction of a high-yield indigo genetic engineering strain and a fermentation method. The present invention uses Escherichia coli as a starting strain, knocks out at least one of the yddG gene, trpR gene, tyrA gene or pheA gene in the host cell; integrates the tryptophanase gene tnaA and / or the flavin monooxygenase gene MaFMO on the genome; integrates one or more genes related to biofilm modification on the genome, and obtains the optimal engineering strain by comparing the fermentation yield; then transfers a plasmid into the strain to further strengthen the tryptophanase gene tnaA and the flavin monooxygenase gene MaFMO; finally, the yield is significantly increased by supplementing carbon sources and substrates and adding surfactants. The present invention provides an indigo-producing genetic engineering strain and a fermentation method with good stability and high synthesis efficiency, providing a reference for the subsequent development of more advantageous engineering strains.

The invention discloses a formate dehydrogenase mutant and application thereof in catalytic synthesis of D-mannitol, and belongs to the technical field of bioengineering. According to the formate dehydrogenase mutant provided by the invention, the 18th-site glutamic acid of wild-type formate dehydrogenase with an amino acid sequence shown as SEQ ID NO.2 is mutated into proline, the 57th-site asparagine is mutated into glutamic acid, the 70th-site histidine is mutated into tryptophan, the 235th-site serine is mutated into threonine, and the 316th-site valine is mutated into threonine, so that the formate dehydrogenase mutant is high in enzyme activity and catalytic activity; the coenzyme circulation efficiency during the production of D-mannitol can be obviously improved, so that the yield of D-mannitol can be effectively improved. When the genetically engineered bacterium co-expressed by the formate dehydrogenase mutant and the mannitol dehydrogenase mutant is used for catalyzing 150 g / L fructose to produce D-mannitol, the yield of D-mannitol within 15 h can reach 140 g / L or above.

The invention relates to a gene modified cell and a method for producing fucosyllactose by using the gene modified cell, in particular to a saccharomyces cerevisiae gene modified cell and application thereof, and belongs to the technical field of biological gene engineering. The present invention provides a genetically modified cell comprising a recombinant nucleic acid sequence encoding a polypeptide having an [alpha]-1, 2-fucosyltransferase polypeptide ([alpha]-1, 2-fucosyltransferase) activity. The alpha-1, 2-fucosyltransferase polypeptide includes, but is not limited to, polypeptides having at least 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99% and 100% identical amino acid sequences with the amino acid sequences of SEQ ID NO: 1-25. According to the gene modified cell, the fucosyllactose synthesis capability of an original strain is improved.

The invention discloses a genetically engineered algae capable of resisting aquatic pathogenic bacteria as well as a construction method and application thereof, and is characterized in that the genetically engineered algae is phaeodactylum tricornutum into which cell wall energizing plasmids pPha-T1-J48054-eGFP-Linker-Q4 or pPha-T1-J48054-eGFP-Linker-Q6 are introduced, and the preparation method of the genetically engineered algae comprises the following steps: taking genome DNA of the phaeodactylum tricornutum as a template; the method comprises the following steps: constructing a directional expression plasmid pPha-T1-J48054-eGFP by amplifying a Phatr3J48054 coding sequence, inserting Q4 and Q6 coding sequences into the downstream of the eGFP of a directional expression vector, constructing a cell wall energizing plasmid, electrically transforming the cell wall energizing plasmid into phaeodactylum tricornutum, coating an f / 2 plate culture medium with transformed phaeodactylum tricornutum cells for culturing, screening positive algae strains, and screening the positive algae strains. The feed additive has the advantage of inhibiting or killing aquatic pathogenic bacteria.

The invention belongs to the field of plant genetic engineering, and discloses application of a vitis amurensis cold-resistant gene VaWRKY65 in plant cold-resistant genetic improvement, the VaWRKY65 gene is a transcription factor separated and cloned from extremely cold-resistant vitis amurensis, and the sequence of the VaWRKY65 gene is shown as SEQ ID NO.1. The invention further discloses a preparation method of the vitis amurensis cold-resistant gene VaWRKY65. The gene is used for constructing an overexpression and interference vector, the overexpression and interference vector is respectively introduced into arabidopsis thaliana and vitis amurensis through agrobacterium tumefaciens-mediated genetic transformation, and biological function verification of the obtained transgenic plant shows that the cloned VaWRKY65 gene has the function of improving the cold resistance of the plant. The discovery of the gene provides a new gene resource for plant stress resistance molecular design breeding and provides a new genetic resource for implementation of green agriculture and water-saving agriculture, and development and utilization of the genetic resource are beneficial to reduction of agricultural production cost and realization of environmental friendliness.

The invention relates to the technical field of genetic engineering, and particularly discloses a genetic engineering bacterium for producing melanin as well as a construction method and application of the genetic engineering bacterium. According to the application, the yield of the melanin can be effectively increased by modifying a metabolic pathway of the genetically engineered bacterium, and the yield of the melanin reaches 6.2 g / L and 18.5 g / L respectively through shake-flask culture and 5L fermentation tank culture. Compared with the prior art, the yield of melanin produced by the genetically engineered bacterium is improved by 30% at the shake flask fermentation level, the fermentation yield of a fermentation tank is improved by 4.3 times, in addition, expensive tyrosine is changed into glucose as a fermentation precursor substance, the production cost is greatly reduced, and an efficient and feasible solution is provided for large-scale production of melanin.

The invention relates to the technical field of biological induction of calcium carbonate deposition, in particular to self-repairing concrete for biological induction of calcium carbonate deposition and a preparation method thereof. The cement comprises the following components in parts by weight: 320-380 parts of Portland cement and the like. The biomineralization composite inducer contains a genetically engineered bacterium solution, a urea-calcium chloride solution and a nano strontium carbonate seed crystal; the nano silicon dioxide-graphene composite powder is prepared by chemical vapor deposition; the wall material of the double-response microcapsule contains a temperature-sensitive polymer, and the core material contains a plurality of components; nanocellulose whiskers are also added; self-repairing is achieved through cooperation of multiple components, and all the components are specially treated or prepared. The self-repairing concrete is high in self-repairing efficiency, and wide cracks can be repaired; the mechanical property is excellent, and the compression strength and the breaking strength are remarkably improved; working performance is good, and construction is convenient; durability is good, and erosion and permeability are resisted; environmental protection and economy are considered, and the application prospect is wide.

The invention discloses a wheat E3 ubiquitin ligase gene RFEL1 and application of the wheat E3 ubiquitin ligase gene RFEL1 in wheat disease resistance, and belongs to the technical field of plant genetic engineering. The invention discloses a nucleotide sequence of a wheat E3 ubiquitin ligase gene RFEL1 as shown in SEQ ID NO. 3. The invention further provides application of the wheat E3 ubiquitin ligase gene RFEL1 or related biological materials thereof. The application comprises any one of the following applications: A1, improving the resistance of wheat to stripe rust; a2, the resistance of wheat to powdery mildew is improved; and A3, the resistance of wheat to leaf rust is improved. The E3 ubiquitin ligase RFEL1 gene provided by the invention not only has broad-spectrum resistance to different stripe rust, but also has resistance to wheat leaf rust and powdery mildew. The E3 ubiquitin ligase RFEL1 gene disclosed by the invention is applied to broad-spectrum resistance breeding of wheat and has important application value.

The invention belongs to the technical field of biology, and particularly provides reverse transcriptase UCRT vZ mutants with improved thermal stability, the reverse transcriptase UCRT vZ mutants comprise four single-point mutants, six double mutants and four three mutants, and compared with wild type reverse transcriptase UCRT vZ, the half-life period of the mutants is longer at 65 DEG C; the double-mutant has a better effect, and the half-life period of the double-mutant is about four times that of the wild reverse transcriptase UCRT vZ. The invention also provides a genetically engineered bacterium containing the mutant. The reverse transcriptase UCRT vZ mutant obtained by the construction method provided by the invention has better thermal stability, shows higher thermal stability when being used for reverse transcription of RNA (Ribonucleic Acid) into cDNA (Complementary Deoxyribose Nucleic Acid) at a higher temperature, and has higher application potential.

The invention provides a Ustilaginoidea virens gene UvASE2 for regulating and controlling rice resistance and application of the Ustilaginoidea virens gene UvASE2, and relates to the technical field of plant genetic engineering. The nucleotide sequence of the Ustilaginoidea virens gene UvASE2 is as shown in SEQ ID NO: 1, and the amino acid sequence of the encoding protein of the Ustilaginoidea virens gene UvASE2 is as shown in SEQ ID NO: 2. By constructing a transgenic rice plant for heterologous expression of UvASE2, it is found that the transgenic rice can significantly improve the resistance to false smut and bacterial blight and significantly induce the outbreak of active oxygen. The heterologous expression UvASE2 gene of Ustilaginoidea virens has the function of positively regulating and controlling the disease resistance of rice, and the UvASE2 gene can be used for improving the disease resistance of rice and has important significance on creation of disease-resistant germplasm of rice.

The invention relates to the field of ulcerative colitis, and discloses a multi-parameter monitoring system for evaluating the intestinal barrier function of ulcerative colitis, which is used for realizing the goal of automatically adjusting a treatment scheme according to a monitoring result by constructing a closed-loop feedback treatment system. According to the invention, by designing the nanoprobe of which the surface is modified with a specific binding element and combining with a swallowing capsule endoscopy, real-time imaging and molecular level dynamic tracking of the intestinal barrier are realized, genetically engineered bacteria are constructed to quantify intestinal permeability abnormality and local inflammation level, and an intestinal barrier function damage score and a disease progress prediction result are output; individual monitoring is achieved through transfer learning, ultrasonic elastography, optical coherence tomography, wearable equipment for measuring intestinal electric field impedance spectroscopy and other technologies are adopted, an intestinal wall mechanics-electrophysiology composite parameter set is obtained, and the evaluation accuracy is improved.

The invention relates to the technical field of plant genetic engineering, in particular to an application of an alfalfa MsPL19 protein and a gene thereof in regulating and controlling the plant height, fresh weight or biological yield of alfalfa. The invention provides an MsPL19 protein, a gene and application thereof, which can obviously improve the plant height, the biological yield and the fresh weight of medicago sativa and further improve the quality of the medicago sativa. Meanwhile, it is found that the MsPL19 protein and gene can respond to low temperature, drought, salt, hormone and other pathways, the protein interacting with MsPL19 is obtained through immunoprecipitation-mass spectrometry analysis, corresponding molecular modules can be enriched, the molecular mechanism of alfalfa MsPL19 responding to the low-temperature environment is analyzed, new cold-resistant varieties can be bred for alpine regions, and the application prospect is broad. And a new breeding direction is provided for increasing the yield of alfalfa.

The invention belongs to the technical field of biology, and particularly provides a reverse transcriptase UCRT v6 mutant with improved thermal stability, the reverse transcriptase UCRT v6 mutant comprises four single-point mutants, six double mutants and four three-point mutants, and compared with wild type reverse transcriptase UCRT v6, the half-life period of the mutant is longer at 65 DEG C; the three mutants are better in effect, and the half-life period of the three mutants is about 5 times that of the wild reverse transcriptase UCRT v6. The invention also provides a genetically engineered bacterium containing the mutant. The reverse transcriptase UCRT v6 mutant obtained by the construction method provided by the invention has better thermal stability, shows higher thermal stability when being used for reverse transcription of RNA (Ribonucleic Acid) into cDNA (Complementary Deoxyribonucleic Acid) at higher temperature, and has higher application potential.

The invention provides a keto-alcohol acid reductoisomerase mutant and application of the keto-alcohol acid reductoisomerase mutant in construction of genetically engineered bacteria for high yield of D-pantothenic acid. In order to solve the technical problem that in the prior art, the yield of D-pantothenic acid synthesized through microbial fermentation is not high, semi-rational design of enzyme is adopted, and a keto-alcohol acid reductoisomerase mutant with substrate specificity is obtained and applied to construction of genetically engineered bacteria for high yield of D-pantothenic acid. According to the invention, a genetically engineered bacterium with high yield of D-pantothenic acid is constructed by utilizing the keto-alcohol acid reductoisomerase mutant through a CRISPR-Cas9 gene editing technology, so that the yield of D-pantothenic acid is increased by about 12.04%, and compared with an original strain, the valine accumulation amount in obtained fermentation liquor is almost unchanged compared with that of a control, and the yield of D-pantothenic acid is greatly improved. However, the accumulation of branched chain amino acid isoleucine is less, so that the modification of the substrate specificity of the keto-alcohol acid reductoisomerase is achieved.

Provided are S-adenosylmethionine synthetase mutants and the use thereof, belonging to the technical field of biological enzyme engineering. Site-directed combinatorial mutations are performed on positions 189, 200, 234, 266 and 371 of S-adenosylmethionine synthetase MAT to obtain a series of mutants with improved enzyme activity, wherein the specific enzyme activity of I189V / V266H and V266H / N371R is increased by more than 10 times relative to the parent. The yields of S-adenosylmethionine synthesized by whole cells of recombinant bacteria expressing mutants I189V / V266H / N371R, V266H / Q234N / N371R and I189V / V266H / Q234N / N371R all reach 1550 mg / L or more. The provided enzyme mutants have broad application prospects in the production of S-adenosylmethionine and the construction of genetically engineered microorganisms for S-adenosylmethionine.

The invention belongs to the technical field of biology, and particularly provides UCRT VI heat-resistant reverse transcriptase mutants with improved thermal stability, the mutants comprise four single-point mutants, six double mutants and four three mutants, and compared with wild-type UCRT VI heat-resistant reverse transcriptase, the mutants have longer half-life period at 65 DEG C; the double mutant has a better effect, and the half-life period of the double mutant is about three times of that of wild type DNA polymerase. The invention also provides a genetically engineered bacterium containing the mutant. The UCRT heat-resistant reverse transcriptase mutant obtained by the construction method provided by the invention has better thermal stability, shows higher thermal stability when being used for synthesizing DNA (Deoxyribonucleic Acid) by reverse transcription at higher temperature, and has higher application potential.

The invention discloses a recombinant XVII type collagen engineering bacterium as well as a preparation method and application thereof, and belongs to the technical field of genetic engineering, and the recombinant XVII type collagen engineering bacterium is realized through three steps of designing and optimizing collagen, improving translation through codon optimization and selecting a vector for cloning. By optimizing the amino acid sequence and the codon, the expression efficiency and the stability of the recombinant XVII type collagen in engineering bacteria are improved. The optimization not only improves the production efficiency of the protein, but also reduces the production cost. The recombinant XVII type collagen has potential in the medical field, especially in the fields of skin repair, wound healing, aging resistance and the like. Meanwhile, in the fields of beauty and biological materials, collagen is widely applied to products such as masks and skin care products as a basic component, and can promote skin cell regeneration and enhance skin elasticity and repair capacity.

The invention discloses a high-efficiency lysine decarboxylase mutant and an application of the high-efficiency lysine decarboxylase mutant in synthesis of pentamethylene diamine. A series of mutants including a single mutant (such as N218G, T222V, C244P and the like), a double mutant and a three mutant are obtained by carrying out multi-site mutation on wild type lysine decarboxylase (SEQ ID NO.2) from Klebsiella grimontii. The catalytic efficiency of the mutant is remarkably improved, and the activity of the mutant is improved by 5.0-10.2 times compared with that of a wild type enzyme. According to the method disclosed by the invention, the substrate conversion rate of 99% or above can be realized within 2 hours through an optimized process of constructing an expression vector and a genetically engineered bacterium, inducing expression of lysine decarboxylase and synthesizing 1, 5-pentanediamine by utilizing a whole-cell catalysis technology. Compared with a traditional chemical method and a natural enzyme method, the method disclosed by the invention has the advantages of simplified process, high catalytic efficiency, low production cost and the like, and is suitable for producing bio-based 1, 5-pentamethylene diamine and nylon 56 salt.

The invention discloses a schizochytrium limacinum genetic engineering strain capable of remodeling an FAS (Fibroblast Activated Sequence) pathway as well as a construction method and application thereof. The schizochytrium limacinum gene engineering strain is obtained by heterologous expression of a C16 elongase gene E16, a C18 elongase gene E18, a delta 9 desaturase gene D9, a delta 5 desaturase gene D5, a delta 6 desaturase gene D6 and a delta 15 desaturase gene D15 in a schizochytrium limacinum wild type. The recombinant schizochytrium limacinum described herein is capable of producing EPA comprising 2.08% by total fatty acids while also producing DHA comprising at least more than 41% by total fatty acids. In addition, the invention discloses a method for producing unsaturated fatty acid through a double-path channel of PKS and FAS, which is beneficial to promotion and application of a technology for producing EPA and DHA by schizochytrium limacinum.

The invention belongs to the technical field of plant genetic engineering, and particularly relates to an SCRE10 gene for improving rice disease resistance and application of the SCRE10 gene, the base sequence of the SCRE10 gene is shown as SEQ ID NO.1, and the amino acid sequence of the SCRE10 gene is shown as SEQ ID NO.2. Through construction of a dexamethasone induced expression SCRE10 transgenic rice plant, it is found that the transgenic rice can significantly induce PR gene expression and active oxygen outbreak, and the resistance of rice to false smut and bacterial leaf blight can be improved. The invention proves that heterologous inducible expression of the Ustilaginoidea virens SCRE10 gene has the function of positively regulating the disease resistance of the rice, and the SCRE10 gene can be used for improving the disease resistance of the rice, which is of great significance to the creation of disease-resistant germplasm of the rice.

The invention relates to the technical field of dye synthesis, and particularly discloses a genetically engineered bacterium for synthesizing N-acetyl blue as well as a construction method and application of the genetically engineered bacterium. The supply capacity of precursor substances glutamic acid and glutamine of the genetically engineered bacterium is high, the fermentation process is simple, the production intensity of the precursor substances glutamine and N-acetylglutamine is improved by cutting off a consumption path, relieving negative feedback inhibition and enhancing the expression level of key genes through the genetically engineered bacterium, and finally the yield of N-acetylblue reaches 41.2 g / L.

The invention belongs to the technical field of plant genetic engineering, and particularly relates to a method for establishing an elymus nutans seed callus induction and regeneration system. The invention provides a tissue culture medium and a tissue culture method for culturing elymus nutans, and in the tissue culture medium provided by the invention, 2, 4-D can induce explants to form calluses and promote cell division and growth. The CH has a good effect on differentiation of embryoid and adventitious buds. ABA can promote the development of seed embryos. The KT can promote the generation of calluses and the growth of adventitious buds. NAA can promote plant growth and promote generation of adventitious roots. Under the combined action of NAA, 2, 4-D, ABA, KT and CH, the callus induction rate of the mature embryo is improved. The invention also provides a regeneration tissue culture method of elymus nutans, the mature embryo is used as an explant for tissue culture, and the callus induction rate of the mature embryo is high.

The invention belongs to the technical field of biology, and particularly relates to a latex duplex immunochromatography test strip for rapidly identifying a porcine transmissible gastroenteritis virus (TGEV) and a porcine epidemic diarrhea virus (PEDV) and a preparation method of the latex duplex immunochromatography test strip. Soluble TGEV N protein and PEDV N protein with immunogenicity and reactivity are respectively obtained by utilizing a prokaryotic expression system, the soluble TGEV N protein and the soluble PEDV N protein are used as immunogenicity to immunize mice, and specific monoclonal antibodies of the TGEV N protein and the PEDV N protein are respectively obtained by utilizing cell fusion and subcloning screening technologies. The antibody variable region gene sequence is obtained by using a nested PCR amplification technology, and can be subsequently obtained by using a gene engineering or protein engineering method. Then, the latex duplex immunochromatography test strip for detecting TGEV and PEDV, which is convenient, rapid and high in sensitivity, and the preparation method are researched and developed on the basis of specific monoclonal antibodies of TGEV N protein and PEDV N protein.

The invention provides a recombinant humanized elastin with high biological activity as well as a preparation method and application thereof, and belongs to the technical field of genetic engineering and biological materials. 100% of the amino acid sequence of the elastin is derived from human elastin and is prepared by expression of genetically engineered bacteria; the protein has a typical beta-spiral hydrophobic structural domain and a lysine-rich hydrophilic structural domain, has a good bionic structure and functional characteristics, can significantly promote proliferation, adhesion and migration of human skin fibroblasts, also has excellent antioxidant, anti-wrinkle and anti-aging activities, and can be used for preparing a biomimetic protein. The hydrogel can be widely applied to the fields of skin repair dressings, injection implants, artificial skin, biomedical materials, functional skin care products and the like; in addition, the elastin is good in solubility, high in stability, mature in expression system and suitable for large-scale production.

Provided herein are fusion polypeptides comprising an amino acid sequence of a bacteriocin, the amino acid sequence of the bacteriocin being a cleavage intein both on both the N-terminus and on both the C-terminus that cyclizes the bacteriocin. Also provided are nucleic acids and genetic vectors encoding the fusion polypeptides, as well as microbial cells genetically engineered with the nucleic acids or genetic vectors. Also provided are methods of making the cyclic bacteriocin, methods of screening using a library of nucleic acids or genetic vectors encoding the fusion polypeptides, and methods of controlling growth of organisms using the cyclic bacteriocin made by the methods provided herein.