%D 2020
%L upm66123
%A Mónica Pantín de Prado
%I Agronomica
%T Estudio de la selectividad de borneol deshidrogenasas de
varias especies de plantas mediante reconstrucción ancestral y expresión recombinante en Escherichia
%C Madrid
%X Terpenoids are a large class of plant natural products with many industrial uses. Thus, pure enantiomers of borneol are fragrant constituents of several essential oils with important applications in the cosmetic industry and in several therapies. Recent studies show that (+)-borneol has anti-inflammatory and neuroprotective effects and (-)-borneol has wound-healing and oxidative damage protection activities. The main natural source of (-)-borneol is the endangered plant Dipterocarpus turbinatus whereas (+)-borneol can be obtained from the plant Blumea balsamifera. Due to the limited supply of these plants, the price of enantiomerically pure borneol is extremely high. Borneol can also be chemically synthesized by reduction methods from racemic camphor, which is a cheap waste material from pine tree processing. However, the quality of pure natural borneol is significantly higher than the chemically synthesized one, because this later product is not optically pure, containing four different stereoisomers: (+)-isoborneol, (-)-isoborneol, (+)-borneol and (-)-borneol. Therefore, there is an increased effort in defining purification methods aiming to separate these different stereoisomers from racemic borneol. On the other hand, within the scope of the international research project “Camphor-based polymers”, the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB are working on an efficient biocatalytic process for the selective functionalization of the camphor into biobased monomers. Enantioselective biocatalysts would be highly desirable for the selective catalytic separation of borneol, isoborneol and camphor stereoisomers under mild reaction conditions. So far, several borneol dehydrogenases from plants and bacteria have been reported, but none have shown sufficient stereoselectivity and stability. This work reports the reconstruction of two ancestors from the borneol dehydrogenase family. Recombinant expression of these enzymes in E. coli has allowed functional characterization of these two borneol dehydrogenases and their comparison to other borneol dehydrogenases currently under study.