Abstract: According to the present disclosure, on the basis of all existing mutations, the tenth glycine of a BC-PC-PLC is mutated into aspartic acid, a specific enzyme activity thereof is 83% higher than that of a sequence before the mutation, and protein expression and degumming activity of unit enzyme activity do not change, so as to further reduce manufacturing costs.

Abstract: Provided is a Pichia pastoris mutant strain for expressing an exogenous gene. Specifically, provided is a Pichia pastoris mutant strain comprising, with respect to Pichia pastoris mutant strain GS115 or CICC32806, one or more of the following six mutations: BQ9382_C1-2260, EKK deletions at positions 308-310, a hypothetical protein; BQ9382_C1-3800, E129K, 60S ribosomal subunit assembly/exported protein LOC1; BQ9382_C1-5700, I312M, mitochondrial external NADH dehydrogenase, type II NAD(P)H:quinone oxidoreductase; BQ9382_C2-3950, Q145X, an essential protein having a binding partner Psr1p and used for completely activating a general stress response; BQ9382_C3-2220, E188K, a hypothetical protein; and BQ9382_C3-4370, W196X, orotidine 5\?-phosphate decarboxylase. The provided Pichia pastoris mutant strain is an effective commonly employed host for exogenous expression, and can efficiently express different proteins, especially phospholipase and lipase.

Abstract: Provided is a polypeptide having phospholipase C activity. The polypeptide has: 1) an amino acid sequence represented by SEQ ID No: 2, comprising amino acid substitutions occurred at one or more positions, wherein the one or more positions are selected from positions 6, 8, 10, 104, and 205 in the amino acid sequence represented by SEQ ID No: 2 or any combination thereof; or 2) having at least 80% sequence identity with 1), and at least one of positions 6, 8, 10, 104 and 205 being different from positions 6, 8, 10, 104, and 205 in the amino acid sequence represented by SEQ ID No: 2. Provided are a nucleic acid molecule for encoding the polypeptide, a vector comprising the nucleic acid molecule, and a cell comprising the nucleic acid molecule or the vector. Provided are uses of the polypeptide, the nucleic acid molecule, the vector, and the cell.

Abstract: Provided in the present invention is a phospholipase C mutant with high enzyme activity, a polypeptide with the sequence as shown in SEQ ID NO:7, or a polypeptide derived from the phospholipase C formed by performing substitution, deletion or addition of one or a plurality of amino acids on the polypeptide of SEQ ID NO:7 while retaining the phospholipase C activity provided by SEQ ID NO:7. The phospholipase C mutant of the present invention can improve degumming efficiency and increase the yield of diacylglycerol (DAG) during degumming.

Abstract: According to the present disclosure, on the basis of all existing mutations, the tenth glycine of a BC-PC-PLC is mutated into aspartic acid, a specific enzyme activity thereof is 83% higher than that of a sequence before the mutation, and protein expression and degumming activity of unit enzyme activity do not change, so as to further reduce manufacturing costs.

Abstract: Provided is a mutant of the wild type phosphatidylcholine-specific phospholipase C of Bacillus cereus. The mutations involved comprise the amino acid residue at position 63 being mutated from asparagine to aspartic acid, the amino acid residue at position 131 being mutated from asparagine to serine, and the amino acid residue at position 134 being mutated from asparagine to aspartic acid, and may comprise the amino acid residue at position 56 being mutated from tyrosine to alanine, lysine, asparagine, glutamine, histidine or tryptophan, and further, may also comprise the amino acid residue at position 106 being mutated from methionine to valine. Also provided are a polynucleotide molecule encoding the mutant, a nucleic acid construct and a host cell comprising the polynucleotide molecule, a composition comprising the mutant, and the use of the mutant, the polynucleotide molecule, the nucleic acid construct and the host cell.

Abstract: Provided is a mutant of the wild type phosphatidylcholine-specific phospholipase C of Bacillus cereus. The mutations involved comprise the amino acid residue at position 63 being mutated from asparagine to aspartic acid, the amino acid residue at position 131 being mutated from asparagine to serine, and the amino acid residue at position 134 being mutated from asparagine to aspartic acid, and may comprise the amino acid residue at position 56 being mutated from tyrosine to alanine, lysine, asparagine, glutamine, histidine or tryptophan, and further, may also comprise the amino acid residue at position 106 being mutated from methionine to valine. Also provided are a polynucleotide molecule encoding the mutant, a nucleic acid construct and a host cell comprising the polynucleotide molecule, a composition comprising the mutant, and the use of the mutant, the polynucleotide molecule, the nucleic acid construct and the host cell.

Abstract: The present invention relates to transcriptional gene silencing (TGS) of endogenes in plants, plant tissue and plant cells. More specifically, the present invention relates to nucleic acid constructs that are capable of more effectively silencing genes of interest, such as endogenes, in plants, plant tissue and plant cells by TGS. The present invention further relates to methods of more effectively reducing endogenous gene expression in plants, plant tissues or plant cells by TGS using the nucleic acid constructs of the invention.

Abstract: The present invention provides compositions and methods for enhancing protein stability in transgenic plants. The compositions are nucleic acid constructs which encode fusion proteins, fusion proteins, transgenic plant cells and transgenic plants. A fusion protein in accordance with the present invention comprises a protein of interest and a UBA1 or UBA2 domain of an Arabidopsis RAD23 protein. The methods use the nucleic acid constructs to produce fusion proteins in transgenic plant cells or transgenic plants. The fusion proteins have greater stability than the protein of interest and have the same function as the proteins of interest.

Abstract: Chemically inducible promoters are described that may be used to transform plants, including tobacco and lettuce, with genes which are easily regulatable by adding the plants or plant cells to a medium containing an inducer of the promoter or by removing the plants or plant cells from such medium. The promoters described are ones that are inducible by a glucocorticoid or estrogen which is not endogenous to plants. Such promoters may be used with a variety of genes such as ipt, CKI1, or knotted1, to induce shoot formation in the presence of an appropriate inducer. The promoters may be used with genes which induce somatic embryos such as Lec1 or SERK to prepare somatic embryos which can be grown into seedlings and then into plants. The promoter may also be used with antibiotic or herbicide resistance genes which are then regulatable by the presence or absence of inducer rather than being constitutive. Other examples of genes which may be placed under the control of the inducible promoter are also presented.

Abstract: Chemically inducible promoters are described that may be used to transform plants, including tobacco and lettuce, with genes which are easily regulatable by adding the plants or plant cells to a medium containing an inducer of the promoter or by removing the plants or plant cells from such medium. The promoters described are ones that are inducible by a glucocorticoid or estrogen which is not endogenous to plants. Such promoters may be used with a variety of genes such as ipt, CKI1, or knotted1, to induce shoot formation in the presence of an appropriate inducer. The promoters may be used with genes which induce somatic embryos such as Lec1 or SERK to prepare somatic embryos which can be grown into seedlings and then into plants. The promoter may also be used with antibiotic or herbicide resistance genes which are then regulatable by the presence or absence of inducer rather than being constitutive. Other examples of genes which may be placed under the control of the inducible promoter are also presented.

Abstract: Chemically inducible promoters are described that may be used to transform plants, including tobacco and lettuce, with genes which are easily regulatable by adding the plants or plant cells to a medium containing an inducer of the promoter or by removing the plants or plant cells from such medium. The promoters described are ones that are inducible by a glucocorticoid or estrogen which is not endogenous to plants. Such promoters may be used with a variety of genes such as ipt, CKI1, or knotted1, to induce shoot formation in the presence of an appropriate inducer. The promoters may be used with genes which induce somatic embryos such as Lec1 or SERK to prepare somatic embryos which can be grown into seedlings and then into plants. The promoter may also be used with antibiotic or herbicide resistance genes which are then regulatable by the presence or absence of inducer rather than being constitutive. Other examples of genes which may be placed under the control of the inducible promoter are also presented.