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Daniel Otzen

Electrostatics in the active site of an α-amylase

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Electrostatics in the active site of an α-amylase. / Nielsen, Jens E.; Beier, Lars; Otzen, Daniel; Borchert, Torben V.; Frantzen, Henrik B.; Andersen, Kim V.; Svendsen, Allan.

In: European Journal of Biochemistry, Vol. 264, No. 3, 15.09.1999, p. 816-824.

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

Harvard

Nielsen, JE, Beier, L, Otzen, D, Borchert, TV, Frantzen, HB, Andersen, KV & Svendsen, A 1999, 'Electrostatics in the active site of an α-amylase', European Journal of Biochemistry, vol. 264, no. 3, pp. 816-824. https://doi.org/10.1046/j.1432-1327.1999.00664.x

APA

Nielsen, J. E., Beier, L., Otzen, D., Borchert, T. V., Frantzen, H. B., Andersen, K. V., & Svendsen, A. (1999). Electrostatics in the active site of an α-amylase. European Journal of Biochemistry, 264(3), 816-824. https://doi.org/10.1046/j.1432-1327.1999.00664.x

CBE

Nielsen JE, Beier L, Otzen D, Borchert TV, Frantzen HB, Andersen KV, Svendsen A. 1999. Electrostatics in the active site of an α-amylase. European Journal of Biochemistry. 264(3):816-824. https://doi.org/10.1046/j.1432-1327.1999.00664.x

MLA

Nielsen, Jens E. et al. "Electrostatics in the active site of an α-amylase". European Journal of Biochemistry. 1999, 264(3). 816-824. https://doi.org/10.1046/j.1432-1327.1999.00664.x

Vancouver

Nielsen JE, Beier L, Otzen D, Borchert TV, Frantzen HB, Andersen KV et al. Electrostatics in the active site of an α-amylase. European Journal of Biochemistry. 1999 Sep 15;264(3):816-824. https://doi.org/10.1046/j.1432-1327.1999.00664.x

Author

Nielsen, Jens E. ; Beier, Lars ; Otzen, Daniel ; Borchert, Torben V. ; Frantzen, Henrik B. ; Andersen, Kim V. ; Svendsen, Allan. / Electrostatics in the active site of an α-amylase. In: European Journal of Biochemistry. 1999 ; Vol. 264, No. 3. pp. 816-824.

Bibtex

@article{69746892f21b4b28befe94375634cb86,
title = "Electrostatics in the active site of an α-amylase",
abstract = "The importance of electrostatics in catalysis has been emphasized in the literature for a large number of enzymes. We examined this hypothesis for the Bacillus licheniformis α-amylase by constructing site-directed mutants that were predicted to change the pk(a) values of the catalytic residues and thus change the pH-activity profile of the enzyme. To change the pk(a) of the catalytic residues in the active site, we constructed mutations that altered the hydrogen bonding network, mutations that changed the solvent accessibility, and mutations that altered the net charge of the molecule. The results show that changing the hydrogen bonding network near an active site residue or changing the solvent accessibility of an active site residue will very likely result in an enzyme with drastically reduced activity. The differences in the pH-activity profiles for these mutants were modest, pH- activity profiles of mutants which change the net charge on the molecule were significantly different from the wild-type pH-activity profile. The differences were, however, difficult to correlate with the electrostatic field changes calculated. In several cases we observed that pH-activity profiles shifted in the opposite direction compared to the shift predicted from electrostatic calculations. This strongly suggests that electrostatic effects cannot be solely responsible for the pH-activity profile of the B. licheniformis α-amylase.",
keywords = "α-Amylase, Active site, Electrostatics, pH-activity profile, Protein engineering",
author = "Nielsen, {Jens E.} and Lars Beier and Daniel Otzen and Borchert, {Torben V.} and Frantzen, {Henrik B.} and Andersen, {Kim V.} and Allan Svendsen",
year = "1999",
month = sep,
day = "15",
doi = "10.1046/j.1432-1327.1999.00664.x",
language = "English",
volume = "264",
pages = "816--824",
journal = "European Journal of Biochemistry",
issn = "0014-2956",
publisher = "Springer-Verlag",
number = "3",

}

RIS

TY - JOUR

T1 - Electrostatics in the active site of an α-amylase

AU - Nielsen, Jens E.

AU - Beier, Lars

AU - Otzen, Daniel

AU - Borchert, Torben V.

AU - Frantzen, Henrik B.

AU - Andersen, Kim V.

AU - Svendsen, Allan

PY - 1999/9/15

Y1 - 1999/9/15

N2 - The importance of electrostatics in catalysis has been emphasized in the literature for a large number of enzymes. We examined this hypothesis for the Bacillus licheniformis α-amylase by constructing site-directed mutants that were predicted to change the pk(a) values of the catalytic residues and thus change the pH-activity profile of the enzyme. To change the pk(a) of the catalytic residues in the active site, we constructed mutations that altered the hydrogen bonding network, mutations that changed the solvent accessibility, and mutations that altered the net charge of the molecule. The results show that changing the hydrogen bonding network near an active site residue or changing the solvent accessibility of an active site residue will very likely result in an enzyme with drastically reduced activity. The differences in the pH-activity profiles for these mutants were modest, pH- activity profiles of mutants which change the net charge on the molecule were significantly different from the wild-type pH-activity profile. The differences were, however, difficult to correlate with the electrostatic field changes calculated. In several cases we observed that pH-activity profiles shifted in the opposite direction compared to the shift predicted from electrostatic calculations. This strongly suggests that electrostatic effects cannot be solely responsible for the pH-activity profile of the B. licheniformis α-amylase.

AB - The importance of electrostatics in catalysis has been emphasized in the literature for a large number of enzymes. We examined this hypothesis for the Bacillus licheniformis α-amylase by constructing site-directed mutants that were predicted to change the pk(a) values of the catalytic residues and thus change the pH-activity profile of the enzyme. To change the pk(a) of the catalytic residues in the active site, we constructed mutations that altered the hydrogen bonding network, mutations that changed the solvent accessibility, and mutations that altered the net charge of the molecule. The results show that changing the hydrogen bonding network near an active site residue or changing the solvent accessibility of an active site residue will very likely result in an enzyme with drastically reduced activity. The differences in the pH-activity profiles for these mutants were modest, pH- activity profiles of mutants which change the net charge on the molecule were significantly different from the wild-type pH-activity profile. The differences were, however, difficult to correlate with the electrostatic field changes calculated. In several cases we observed that pH-activity profiles shifted in the opposite direction compared to the shift predicted from electrostatic calculations. This strongly suggests that electrostatic effects cannot be solely responsible for the pH-activity profile of the B. licheniformis α-amylase.

KW - α-Amylase

KW - Active site

KW - Electrostatics

KW - pH-activity profile

KW - Protein engineering

UR - http://www.scopus.com/inward/record.url?scp=0033568136&partnerID=8YFLogxK

U2 - 10.1046/j.1432-1327.1999.00664.x

DO - 10.1046/j.1432-1327.1999.00664.x

M3 - Journal article

C2 - 10491128

AN - SCOPUS:0033568136

VL - 264

SP - 816

EP - 824

JO - European Journal of Biochemistry

JF - European Journal of Biochemistry

SN - 0014-2956

IS - 3

ER -