107 results about "Esterase Gene" patented technology

The present invention provides novel genes encoding Class II acyl-ACP thioesterases and variants thereof that are active on C8, C10, C12, C14, C16, and C18 acyl-ACP substrates. The thioesterases can be introduced into transgenic organisms, including microorganisms and photosynthetic organisms, for producing fatty acids and fatty acid products.

The invention discloses a deep-sea sediment-sourced novel esterase EST4 as well as an encoding gene and application thereof. A deep-sea sediment-sourced esterase gene est4 is obtained by screening a metagenome and has a nucleotide sequence shown as SEQ ID NO. 1, and the esterase EST4 encoded thereby has an amino acid sequence shown as SEQ ID NO. 2. After heterologous expression of the esterase gene provided by the invention, the catalytic activity is highest when a substrate is p-nitrophenol caproate (C6) and the enzymatic activity is 56.1U/mg. The optimum temperature for catalytic hydrolysis of the esterase EST4 is 35-40 DEG C; in the presence of Ca<2+>, Co<2+>, Sr<2+> and Zn<2+>, the enzymatic activity is increased. The esterase can be applied to chiral medicine synthesis, food processing and food flavor modification, wastewater treatment and washing industry and other industrial productions.

The invention provides feruloyl esterase and a preparing method and application thereof. A feruloyl esterase gene coming from a soil macro gene library have the nucleotide sequence and amino acid sequence shown in SEQ ID NO.1 and SEQ ID NO.2. The gene contains a tetrapeptide SXXK sequence motif which is rarely seen, and after the esterase gene is inserted into plasmid pET28a(+), the gene is transformed into escherichia coli BL21(DE3) to achieve heterogeneous expression. The molecular weight of purified recombinase (DLFae4) is 38.3 kDa. Besides, it is put forward for the first time that novel feruloyl esterase can hydrolyze penbritin, penicillin, cefazolin and other lactam antibiotics. As is shown by site-directed mutagenesis experiments, a catalysis triplet of DLFae4 is composed of serine(S11), histidine (H74) and aspartic acid (D302), and the mutation of any of serine (S11), histidine (H74) and aspartic acid (D302) can cause loss of the catalysis capability of DLFae4. DLFae4 has a high hydrolytic activity on methyl ferulate and has good heat stability. In the presence of cellulase, DLFae4 can obviously increase the amount of ferulic acid released from destarched wheat bran. Due to peculiar activities and enzymatic characteristics of novel feruloyl esterase, novel feruloyl esterase can be applied to feed, paper making, food, pharmacy and other fields.

The invention discloses recombinant bacteria using xylose to produce glycollic acid and a building method and application of the recombinant bacteria and belongs to the technical field of genetic engineering. The xylose dehydrogenase gene, xylonic acid lactonase gene, xylonic acid dehydratase gene, 3-deoxygenation-D-glycerin ketopentose acid aldolase gene and glycolic aldehyde dehydrogenase gene in the recombinant bacteria using the xylose to produce the glycollic acid are overexpressed. Meanwhile, the invention further provides a preparation method of the recombinant bacteria and a method using the recombinant bacteria to produce the glycollic acid. By the recombinant bacteria, the biological synthesizing path using D-xylose as the carbon source to form the glycollic acid through glycolic aldehyde conversion is achieved for the first time.

The invention relates to an esterase gene and the cloning and expression and application thereof and belongs to the field of bioengineering. The substrate characteristic of the esterase gene is disclosed. The esterase is wide in application range and high in industrial application value.

The invention provides a new esterase gene named Est_p1 and a recombination expression system thereof. The gene is cloned from the metagenomic library of the marginal mud 100 meters under the South China Sea. The gene is an 891bp long amino acid numbered 296, which successfully constructs a recombination expression system of a colon bacillus named pET28a-Est_p1/ BL21. The molecular weight of a target protein is 33.5 kD. With pNP-butyric ester as catalyzing substrates, the Est_p1 is proved to be a mildly alkaline medium temperature esterase. The Est_p1 has strong catalytic activity for short esters and is applicable to esterification and transesterification industries.

The invention relates to acquisition of an esterase gene, and cloning and expression and application thereof, which belong to the field of bioengineering. The invention discloses a substrate characteristic of the esterase gene. An esterase has a wide function and an important industrial application value.

There is provided a recombinant bacterium comprising at least one overexpressed acyl-ACP thioesterase gene, and wherein at least one gene from the tricarboxylic acid cycle or glycolysis or both is inactivated. There is also provided a method for producing fatty acids, said method comprising culturing bacteria comprising at least one overexpressed acyl-ACP thioesterase gene in a growth medium in a container having walls; allowing said bacteria to secrete fatty acids; and collecting said fatty acids. Acid supplementation is also shown to increase productivity.

The invention discloses novel deep-sea low-temperature salt-tolerant esterase E10 and a coding gene and application thereof. The invention relates to the esterase gene e10 coming from deep-sea bacteria Croceicoccus marinus E4A9T, and a nucleotide sequence is shown in SEQ ID No.1. After heterologous expression is conducted on an esterase gene, when a substrate is p-nitro phenol caproate (C6), the catalytic activity is the maximum, and the enzyme activity is 29.4 U/mg. The optimum temperature of esterase catalytic hydrolysis of the esterase E10 ranges from 15 DEG C to 20 DEG C; the activity remains 80 percent or above in 1 mol/L NaCl; under the condition of adding organic solvent of dimethyl sulfoxide, glycerin and isopropanol, the enzyme activity is increased. The esterase has the advantages of being low in temperature, resistant to salt and capable of being applied to industrial production such as chiral drug synthesis, food processing and food flavor improvement, wastewater treatment and washing industry under the low-temperature salt-containing condition.

The invention provides a pectin methylesterase gene Pcpme l cloned from phytophthora capsici and a preparation technique of a protein thereof, belonging to the technical field of biology. The invention proves that the pectin methylesterase gene Pcpme l effectively participates in the processes of infecting a host by the phytophthora capsici and causing the disease course of phytophthora capsici leonian on the basis of gene and protein levels and also proves that the protein coded by the pectin methylesterase gene Pcpme l has property of destroying leaf tissue cells and cell wall structures thereof to enable destroyed parts to generate obvious symptoms on the basis of a cell chemistry technique, thus the pectin methylesterase gene Pcpme l is an important target pathogenic gene of a coded phytophthora capsici pectin methylesterase gene cluster. The invention provides sufficient technical reserve for further researching a germ molecule detection technique.

The invention relates to obtaining, cloning expression and applications of an esterase gene, belongs to the field of biological engineering, and discloses substrate properties, wherein the esterase has wide effects and important industrial application values.

The invention discloses thermophilic esterase derived from an aquifex aeolicus strain and functional verification of the thermophilic esterase, and belongs to the field of bioengineering technology. According to the invention, a novel thermophilic esterase gene is discovered, three expression systems are constructed, and efficient expression and research of enzymatic properties are achieved. Construction of an eukaryotic expression system: preferably, a vector pPIC9K is adopted for expression vector construction, and a pichia pastoris host, preferably GS115, is transformed, so that efficient expression is achieved; construction of a prokaryotic escherichia coli expression system: preferably, a vector MBP3 is adopted for expression vector construction, and escherichia coli hosts, preferably BL21 and Origami2, are transformed, so that efficient expression is achieved; and construction of a prokaryotic bacillus megaterium expression system: preferably, a vector pHIS1525 is adopted for expression vector construction, and a bacillus megaterium host, preferably YYBm1, is transformed, so that efficient expression is achieved. The recombinant enzyme (the thermophilic esterase) has the advantages of esterase activity, ,thermophilic characteristic, thermal stability and the like; and the recombinant enzyme has a great potential in industrial application under a high-temperature condition.

The invention discloses an esterase gene estZ, an esterase gene estZ encoded protein and application of the esterase gene estZ. The esterase gene estZ has a total length of 1,206bp, has a G and C content of 65.2% and has a nucleotide sequence as shown in SEQ ID NO. 1. The esterase gene estZ is an encoded product and contains 401 amino acids, and the sequence of the amino acids is shown in SEQ ID NO. 2. The esterase gene estZ is capable of catalyzing and degrading ester bond containing pesticides like beta cypermethrin, lambda cyhalothrin, deltamethrin, cypermethrin, fenpropathrin, bifenthrin, kresoxim-methyl, pyraclostrobin and azoxystrobin. An enzyme preparation produced from the esterase gene estZ can be used for removing pesticide residue in agricultural products such as vegetables, fruits, tea leaves, cotton and tobacco so that the quality of the agricultural products can be improved and the additional value of the agricultural products can be increased. The esterase gene estZ can be further used for producing genetically modified crops so that the problem of excessive pesticide residue in agricultural products can be solved and pollution-free green agricultural products can be produced. The esterase gene estZ can be also used for restoring pesticide contaminated soil so that the problem of environmental pollution can be solved and the ecological environment and the human health can be protected.

The invention discloses esterase as well as encoding genes and application thereof. The amino acid sequence of the esterase is shown in SEQ ID NO.2. The esterase genes are obtained by cloning from pseudomonas Pseudomonas CGMCC NO.4184, and the esterase expressed by the genes has the characteristics of high expression quantity, high selectivity and chiral selectivity. The engineering bacteria containing the esterase genes are applied to a method for catalyzing hydrolysis of rac-2-carboxyethyl-3-cyano-5-methyl ethyl caproate so as to prepare 2-carboxyethyl-(S)-3-cyano-5-methyl ethyl caproate, and when the conversion rate of the reaction is controlled to exceed 50 percent, the unhydrolyzed high-purity 2-carboxyethyl-(S)-3-cyano-5-methyl ethyl caproate can be obtained.

The invention discloses a preparation method for archaea thermophilic esterase and (S)-ketoprofen. The method comprises preparation of a strain, a plasmid, enzymes and a culture medium, PCR amplification and construction of recombinant plasmid, and inducible expression of a gene and purification of protein. Specifically, the method comprises the following steps: (1) designing a pair of primers, carrying out amplification with a whole genome sequence of Thermotogamaritima as a template, carrying out enzyme digestion with endonuclease, connecting the primers to pET15b which has undergone enzyme digestion by same endonuclease, transforming ligation productsinto escherichia coli DH5 alpha, carrying out screening to obtain a recombinant plasmid and carrying out double digestion and sequencing confirmation; and (2) carrying out inducible expression of the gene and purification of the protein so as to obtain the archaea thermophilic esterase. According to the invention, through usage of a genetic engineering method, the gene of the esterase is cloned and expressed in escherichia coli, the protein of the esterase is prepared, and the protein has a high purity (more than 95%). The optimal reaction temperature and the reaction pH value of the esterase are 70 DEG C and 5.0 to 5.5, respectively; the esterase has good acid resistance and can maintain about 50% of its activity when treated for 60 min in a reaction system where the temperature is 70 DEG C and the pH value is 4.5.