摘要:
The present invention concerns a mutant cephalosporin C acylase derived from a precursor of the formula:A.sup.1-268 --X.sup.1 --Tyr--X.sup.2 --A.sup.272-304 --X.sup.3 --A.sup.306-773(SEQ ID NO:1), wherein:A.sup.1-268 is the same amino acid sequence as that from Thr.sup.1 to Gly.sup.268 of native CC acylase,A.sup.272-304 is the same amino acid sequence as that from Gln.sup.272 to Tyr.sup.304 of native CC acylase,A.sup.306-773 is the same amino acid sequence as that from Val.sup.306 to Ala.sup.773 of native CC acylase,X.sup.1 is Met or other amino acid,X.sup.2 is Ala or Tyr, andX.sup.3 is Cys or Ser,provided that when X.sup.1 is Met and X.sup.2 is Ala, X.sup.3 is Ser; and that the mutant cephalosporin C acylase has a property selected from the group consisting of higher enzymatic potency and higher processing efficiency, as compared to native CC acylase. The present invention also concerns DNA encoding the mutant cephalosporin C acylase, an expression vector containing the DNA, a host cell transformed with the expression vector, a process for producing the mutant cephalosporin C acylase by culturing the transformed host cell, and a process for preparing a cephalosporin C using the mutant cephalosporin C acylase.
摘要翻译:本发明涉及衍生自下式的前体的突变型头孢菌素C酰基转移酶:A1-268-X1-Tyr-X2-A272-304-X3-A306-773(SEQ ID NO:1),其中:A1-268是 与天然CC酰基转移酶A272-304的Thr1至Gly268相同的氨基酸序列与天然CC酰基转移酶从Gln272至Tyr304的氨基酸序列相同,氨基酸序列与Val306至 天然CC酰基转移酶的Ala773,X1是Met或其他氨基酸,X2是Ala或Tyr,X3是Cys或Ser,条件是当X1是Met,X2是Ala时,X3是Ser; 并且与天然CC酰基转移酶相比,突变型头孢菌素C酰基转移酶具有选自较高酶效力和较高加工效率的性质。 本发明还涉及编码突变型头孢菌素C酰基转移酶的DNA,含有DNA的表达载体,用表达载体转化的宿主细胞,通过培养转化的宿主细胞产生突变型头孢菌素C酰基转移酶的方法,以及制备 使用突变型头孢菌素C酰基转移酶的头孢菌素C。
摘要:
DNA fragments which contain a sequence of DNA which encodes a protective peptide-fused &agr;-hANP in which the protective peptide has a C-terminus lysine residue which is directly fused to the N-terminus of the &agr;-hANP, vectors which contain such a DNA sequence, and microorganisms transformed which such a vector are useful for the production of &agr;-hANP.
摘要:
An expression vector containing both a DNA encoding an L-sorbose dehydrogenase and a DNA encoding an L-sorbosone dehydrogenase; a transformant having an ability to produce 2-keto-L-gulonic acid (hereinafter 2KLGA) at high yields from D-sorbitol, which is prepared by transforming, with said expression vector, a microorganism capable of producing L-sorbose at high yields from D-sorbitol, which has no or low 2KLGA-decomposing activity or a host microorganism having, in addition to the above-mentioned properties, no or low L-idonic acid-producing activity; and a process for producing 2KLGA, which comprises culturing said transformant in a medium containing D-sorbitol. According to the present invention, 2KLGA useful for the production of L-ascorbic acid can be produced with ease and in larger amounts by a single operation of culture.
摘要:
A novel L-sorbose dehydrogenase (SDH) and a novel L-sorbosone dehydrogenase both derived from Gluconobacter oxydans T-100, a DNA which encodes the SDH and/or SNDH, an expression vector which contains the DNA, a host cell transformed by the expression vector and a process for producing the SDH and/or SNDH, which comprises culturing the host cell in a medium and recovering the SDH and/or SNDH from the resulting culture. The SDH and SNDH of the present invention are useful enzymes having preferable properties for the production of 2-keto-L-gulonic acid, as well as L-ascorbic acid. According to the production method of the present invention, the SDH and SNDH having such preferable properties can be produced in large amounts by genetic engineering.
摘要:
A novel L-sorbose dehydrogenase (SDH) and a novel L-sorbosone dehydrogenase both derived from Gluconobacter oxydans T-100, a DNA which encodes the SDH and/or SNDH, an expression vector which contains the DNA, a host cell transformed by the expression vector and a process for producing the SDH and/or SNDH, which comprises culturing the host cell in a medium and recovering the SDH and/or SNDH from the resulting culture. The SDH and SNDH of the present invention are useful enzymes having preferable properties for the production of 2-keto-L-gulonic acid, as well as L-ascorbic acid. According to the production method of the present invention, the SDH and SNDH having such preferable properties can be produced in large amounts by genetic engineering.
摘要:
Two-cistronic Met-IGF-I expression vector, in which the first cistron encodes a protective peptide with a molecular weight of about 500-50,000 and the second cistron encodes IGF-I, was provided. Also provided is a process for preparing Met-IGF-I, which comprises transforming E. coli with said vector and growing the resultant transformant, followed by the lysis of the cell culture and isolation of Met-IGF-I.
摘要:
An expression vector containing both a DNA encoding an L-sorbose dehydrogenase and a DNA encoding an L-sorbosone dehydrogenase; a transformant having an ability to produce 2-keto-L-gulonic acid (hereinafter 2KLGA) at high yields from D-sorbitol, which is prepared by transforming, with said expression vector, a microorganism capable of producing L-sorbose at high yields from D-sorbitol, which has no or low 2KLGA-decomposing activity or a host microorganism having, in addition to the above-mentioned properties, no or low L-idonic acid-producing activity; and a process for producing 2KLGA, which comprises culturing said transformant in a medium containing D-sorbitol. According to the present invention, 2KLGA useful for the production of L-ascorbic acid can be produced with ease and in larger amounts by a single operation of culture.
摘要:
A novel L-sorbose dehydrogenase (SDH) and a novel L-sorbosone dehydrogenase (SNDH) both derived from Gluconobacter oxydans T-100, a DNA which encodes the SDH and/or SNDH, an expression vector which contains the DNA, a host cell transformed by the expression vector and a process for producing the SDH and/or SNDH, which comprises culturing the host cell in a medium and recovering the SDH and/or SNDH from the resulting culture. The SDH and SNDH of the present invention are useful enzymes having preferable properties for the production of 2-keto-L-gulonic acid, as well as L-ascorbic acid. According to the production method of the present invention, the SDH and SNDH having such preferable properties can be produced in large amounts by genetic engineering.
摘要:
A mutant CC acylase wherein at least one amino acid at the Ala.sup.49, Met.sup.164, Ser.sup.166, Met.sup.174, Glu.sup.358, Met.sup.465, Met.sup.506, or Met.sup.750 position of the amino acid sequence of the native CC acylase is replaced by a different amino acid, a DNA coding therefor, an expression vector containing the said DNA, a microorganism transformed with the said expression vector, the production of the CC acylase by culturing the said transformant, and use thereof for the production of a compound. The mutant CC acylase of the invention has desirable properties in terms of enzymatic potency, alteration of pH profile, efficiency of processing, and the like.
摘要:
The cysteine-containing polypeptide is oxidized with hydrogen peroxide to produce the biologically active polypeptide having the intramolecular disulfide bridge.