Protective Effect of Biomass Components Against Interfacial Inactivation of α-Pinene Oxide Lyase from Pseudomonas rhodesiae CIP 107491

Denis Linares, Pierre Fontanille and Christian Larroche*

Laboratory of Chemical and Biochemical Engineering, Polytech’Clermont-Ferrand – University Blaise Pascal, BP 206, FR-63174 Aubière Cedex, France

Article history:

Received June 3, 2006
Accepted September 12, 2007

Key words:

bioconversion, isonovalal, interfacial inactivation, Pseudomonas rhodesiae CIP 107491, protective effect


α-Pinene oxide lyase is able to catalyze the cleavage of both rings of α-pinene oxide to form cis-2-methyl-5-isopropylhexa-2,5-dienal (isonovalal) with no cofactor requirements. This bioconversion, when carried out under biphasic conditions (water/hexadecane) by Pseudomonas rhodesiae CIP 107491, allows the accumulation of a very high concentration of the product. Nevertheless, the reaction stopped due to the loss of enzyme activity, which has been demonstrated to be an irreversible phenomenon. The enzyme was purified by chromatographic methods to study the reasons of its instability. Bioconversion with pure enzyme showed that a protein precipitation occurred at the liquid-liquid interface, giving rise to a decrease in soluble protein and in residual enzymatic activity. The rate of decrease in soluble protein concentration was not related to the presence of the precursor, which indicated that the inactivation was interfacial, i.e. due to the direct contact of the enzyme with the hexadecane layer. This phenomenon was not present when crude enzymatic extract was used as a biocatalyst. Biomass components present in this extract thus had a protective effect against interfacial phenomena, demonstrating that α-pinene oxide lyase purification does not attract much practical interest for isonovalal production.

*Corresponding author: 
                                               ++33 47 34 07 429
                                               ++33 47 34 07 829

We use cookies to improve our website and your experience when using it. Cookies used for the essential operation of the site have already been set. To find out more about the cookies we use and how to delete them, see our privacy policy.

I accept cookies from this site.

EU Cookie Directive Module Information