Can conformational changes be responsible for solvent and excipient effects on the catalytic behavior of subtilisin Carlsberg in organic solvents?

Journal Article · Thu Feb 20 04:00:00 EST 1997 · Biotechnology and Bioengineering

DOI:https://doi.org/10.1002/(SICI)1097-0290(19970220)53:4<351::AID-BIT1>3.0.CO;2-M· OSTI ID:566337

Griebenow, K; Klibanov, A M ^[1]

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1. Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Chemistry

A growing number of studies are devoted to enhancing enzymatic activity in organic solvents. The authors developed and FTIR (Fourier transform infrared) methodology for quantitatively assessing the secondary structure of proteins suspended in nonaqueous media. This methodology was used to measure the percentages of {alpha}-helices and {beta}-sheets of subtilisin Carlsberg, prepared under different conditions, placed in various organic solvents. The title question was addressed with respect to some instances of markedly influencing the subtilisin activity in organic solvents reported in the literature. It is concluded that the mechanism of subtilisin activation by KCl and N-Ac-L-Phe-NH{sub 2} present in the aqueous solution of the enzyme prior to lyophilization may be due to their preservation of the secondary structure, otherwise altered by the dehydration. Likewise, subtilisin inactivation in the protein-dissolving solvent DMSO (dimethyl sulfoxide) is likely caused by enzyme denaturation (the loss of both {alpha}-helices and {beta}-sheets). On the other hand, some other ligands, as well as protein nondissolving organic solvents, while greatly affecting the subtilisin activity, have little effect on its secondary structure, thus ruling out the causal relationship between the two.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• OSTI ID: 566337
• Journal Information: Biotechnology and Bioengineering, Journal Name: Biotechnology and Bioengineering Journal Issue: 4 Vol. 53; ISSN BIBIAU; ISSN 0006-3592
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
BIODEGRADATION
ENZYME ACTIVITY
FOURIER TRANSFORMATION
MOLECULAR STRUCTURE
ORGANIC SOLVENTS
SERINE PROTEINASES