EP0252666B1
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EP
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Chimeric enzymes
Assignee: Novo Nordisk AS
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Filing: 1987-06-30
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Granted: 1993-06-23
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Expires: 2007-06-30
Abstract
Abstract Chimeric alpha-amylases are disclosed of the formula Q-R-L in which Q is a N-terminal polypeptide residue of from 55 to 60 amino acid residues which is at least 75 percent homologous to the 55 N-terminal amino acid residues in the Bacillus amyloliquefaciens alpha-amylase as described in Takkinen et al., J. Biol. Chem. 258 (1983) 1007-1013, R is a polypeptide residue of the general formula <CHEM> in which X8 comprises His or Gln, X9 comprises Gly or Ser, and X10 comprises Ser or Asp; and L comprises a C-terminal polypeptide of from 390 to 400 amino acid residues which is at least 75 percent homologous to the 395 C-terminal amino acid residues in the Bacillus licheniformis 584 (ATCC 27811) alpha-amylase.
Inventors
- 👤 Borge Krag Diderichsen
- 👤 Helle Outtrup
- 👤 Martin Schülein
- 👤 Barrie Edmund Norman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 05:18
CPC Classifications
C; C12; C12N; C12N9/00; C12N9/14; C12N9/24; C12N9/2402; C12N9/2405; C12N9/2408; C12N9/2411; C12N9/2414; C12N9/2417; C12P; C12P19/00; C12P19/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
93 words
A process for the production of a chimeric alpha-amylase comprising: (a) recombining in vivo the N-terminal coding region of the alpha-amylase gene of B. amyloliquefaciens with the C-terminal coding region of the alpha-amylase gene of B. licheniformis to form recombinants; (b) selecting the recombinants that produce a chimeric alpha-amylase that is thermostable and exhibits a reduced negative effect on the use of A. niger glucoamylase and B. acidopullulyticus pullulanase for the saccharification of starch; (c) culturing the selected recombinants in an appropriate growth medium, and (d) recovering the chimeric alpha-amylase from the culture.
Claim 2
Dependent Claim
172 words
A process for converting starch into high dextrose syrup, comprising: (a) reacting the starch with a chimeric alpha-amylase, which is thermostable and exhibits a reduced negative effect on the use of A. niger glucoamylase and B. acidopullulyticus pullulanase for the saccharification of starch, having the general formula I in which Q comprises a N-terminal part of from 55 to 60 amino acid residues which is at least 75% homologous to the 55 N-terminal amino acid residues in the Bacillus amyloliquefaciens alpha-amylase as described in Takkinen et al., J. Biol. Chem. 258 (1983) 1007-1013; R comprises a part of the general formula Ia in which X₈ comprises His or Gln, X₉ comprises Gly or Ser, X₁₀ comprises Ser or Asp; and L comprises a C-terminal part of from 390 to 400 amino acid residues which is at least 75% homologous to the 395 C-terminal amino acid residues in the Bacillus licheniformis 584 (ATCC 27811) alpha-amylase, to form oligosaccharides: and (b) reacting the oligosaccharides formed in step (a) with a glucoamylase to form dextrose.
Claim 3
Dependent Claim
21 words
A process according to Claim 2, wherein, in the chimeric alpha-amylase, X₈ comprises His, X₉ comprises Gly, and X₁₀ comprises Ser.
Claim 4
Dependent Claim
21 words
A process according to Claim 2, wherein, in the chimeric alpha-amylase X₈ comprises Gln, X₉ comprises Ser, and X₁₀ comprises Asp.
Claim 5
Dependent Claim
18 words
A process according to Claim 2, wherein, in the chimeric alpha-amylase, the homologies are at least 80 percent.
Claim 6
Dependent Claim
18 words
A process according to Claim 2, wherein, in the chimeric alpha-amylase the homologies are at least 90 percent.
Claim 7
Dependent Claim
59 words
A process according to Claim 2, wherein, in the chimeric alpha-amylase, Q comprises an N-terminal part of the general formula Ib in which X₁ comprises Ala-Asn-Leu or Val, X₂ comprises Met or Thr, X₃ comprises Ser-Ala-Tyr or Ala-Glu-His, X₄ comprises Ala-Gly-His or Ser-Asp-Ile, X₅ comprises Thr or Leu, X₆ comprises Ala or Ser, and X₇ comprises Val or Asn.
Claim 8
Dependent Claim
33 words
A process according to Claim 7, wherein, in the chimeric alpha-amylase, X₁ comprises Val, X₂ comprises Thr, X₃ comprises Ala-Glu-His, X₄ comprises Ser-Asp-Ile, X₅ comprises Leu, X₆ comprises Ser, and X₇ comprises Asn.
Claim 9
Dependent Claim
62 words
A process for converting starch into high dextrose syrup, comprising: (a) reacting the starch with a chimeric alpha-amylase to form oligosaccharides; and (b) reacting the oligosaccharides formed in step (a) with a glucoamylase to form dextrose, the chimeric alpha-amylase being as defined in Claim 5, 6, 7 or 8 and in which L comprises a C-terminal part of the general formula Ic
References Cited (Backward Citations)
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