Control of acid-base conditions in low-water media

J. Partridge, N. Harper, B.D. Moore, P.J. Halling, E.N. Vulfson (Editor), P.J. Halling (Editor), H.L. Holland (Editor)

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

The catalytic activity of an enzyme is profoundly affected by its ionisation state, whether it is dissolved in aqueous solution or suspended in low water organic media. In aqueous solution, counter ions can freely move around in solution. Since they are not closely associated with opposite charges, their identity does not effect the protonation state of the enzyme and so pH alone governs the protonation state. When a biocatalyst is suspended in low water organic solvent, the situation is more complex. In this case, counter ions are in closer contact with the opposite charges on the enzyme because of the lower dielectric constant of the medium. Thus, protonation of ionisable groups on the enzyme will be controlled by the type and availability of these ions as well as hydrogen ions. Changes in ionisation state of the protein can therefore be described by 2 equilibria which can, in theory, be controlled independently.
LanguageEnglish
Title of host publicationMethods in Biotechnology: Enzymes in Nonaqueous Solvents
Place of PublicationNJ, USA
Pages227-234
Number of pages7
Edition15
Publication statusPublished - 2001

Publication series

NameMethods in Biotechnology
PublisherHumana Press

Fingerprint

Protonation
Acids
Water
Enzymes
Radiation counters
Ionization
Organic solvents
Protons
Catalyst activity
Permittivity
Availability
Ions
Proteins

Keywords

  • acid-base conditions
  • low water media
  • enzymes

Cite this

Partridge, J., Harper, N., Moore, B. D., Halling, P. J., Vulfson, E. N. (Ed.), Halling, P. J. (Ed.), & Holland, H. L. (Ed.) (2001). Control of acid-base conditions in low-water media. In Methods in Biotechnology: Enzymes in Nonaqueous Solvents (15 ed., pp. 227-234). (Methods in Biotechnology). NJ, USA.
Partridge, J. ; Harper, N. ; Moore, B.D. ; Halling, P.J. ; Vulfson, E.N. (Editor) ; Halling, P.J. (Editor) ; Holland, H.L. (Editor). / Control of acid-base conditions in low-water media. Methods in Biotechnology: Enzymes in Nonaqueous Solvents. 15. ed. NJ, USA, 2001. pp. 227-234 (Methods in Biotechnology).
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Partridge, J, Harper, N, Moore, BD, Halling, PJ, Vulfson, EN (ed.), Halling, PJ (ed.) & Holland, HL (ed.) 2001, Control of acid-base conditions in low-water media. in Methods in Biotechnology: Enzymes in Nonaqueous Solvents. 15 edn, Methods in Biotechnology, NJ, USA, pp. 227-234.

Control of acid-base conditions in low-water media. / Partridge, J.; Harper, N.; Moore, B.D.; Halling, P.J.; Vulfson, E.N. (Editor); Halling, P.J. (Editor); Holland, H.L. (Editor).

Methods in Biotechnology: Enzymes in Nonaqueous Solvents. 15. ed. NJ, USA, 2001. p. 227-234 (Methods in Biotechnology).

Research output: Chapter in Book/Report/Conference proceedingChapter

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AU - Moore, B.D.

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KW - low water media

KW - enzymes

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M3 - Chapter

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T3 - Methods in Biotechnology

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BT - Methods in Biotechnology: Enzymes in Nonaqueous Solvents

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Partridge J, Harper N, Moore BD, Halling PJ, Vulfson EN, (ed.), Halling PJ, (ed.) et al. Control of acid-base conditions in low-water media. In Methods in Biotechnology: Enzymes in Nonaqueous Solvents. 15 ed. NJ, USA. 2001. p. 227-234. (Methods in Biotechnology).