Whole‐Cell Biocatalysis in Seawater: New Halotolerant Yeast Strains for the Regio‐ and Stereoselectivity Reduction of 1‐Phenylpropane‐1,2‐Dione in Saline‐Rich Media

Abstract

The application of green chemistry concepts in catalysis has considerably increased in recent years, and the interest in using sustainable solvents in the chemical industry is growing. One of the recent proposals to fall in line with this is to employ seawater as a solvent in biocatalytic processes. This involves selecting halotolerant strains capable of carrying out chemical conversions in the presence of the salt concentrations found in this solution. Recent studies by our group have revealed the interest in using strains belonging to Debaryomyces and Schwanniomyces for catalytic processes run in this medium. In the present work, we select other yeasts based on their halotolerance to widen the scope of this strategy. We consider them for the monoreduction of 1‐phenylpropane‐1,2‐dione, a well‐characterized reaction that produces acyloin intermediates of pharmaceutical interest. The results obtained herein indicate that using seawater as a solvent for this reaction is possible. The best ones were obtained for Saccharomyces cerevisiae FY86 and Kluyveromyces marxianus, for which acyloins with different stereochemistry were obtained with good to excellent enantiomeric excess.

Developing a broad-range promoter set for metabolic engineering in the thermotolerant yeast Kluyveromyces marxianus

“…Due to its native stress tolerance, the yeast Kluyveromyces marxianus is a promising eukaryotic host for bioproduction. Various strains of this species are able to grow at 45 ​°C and above and in media with high salt concentration (≥5% NaCl) ( Andreu and Del Olmo, 2020 ; Nonklang et al., 2008 ; Yuan et al., 2008 ; Lane and Morrissey, 2010 ). K. marxianus also benefits from the ability to metabolize a range of C5, C6, and C12 sugars and exhibits the fastest growth rate (~0.7 h −1 ) of any known eukaryote ( Löbs et al., 2016 , 2017 ; Rodrussamee et al., 2011 ).…”

Clostridium thermocellum as a Promising Source of Genetic Material for Designer Cellulosomes: An Overview

“…Generally, the incorporation of more catalytic enzymes onto the primary Scaf results in higher synergy for substrate decomposition [70]. The thermotolerant K. marxianus has several advantages (e.g., a wide range of sugars assimilation, thermo, salinity, and toxin tolerance, a wide range of pH, high ethanol yield at elevated temperature) for industrial applications [71,72], and therefore it could be used as an alternative to S. cerevisiae in specific conditions. Recently, the anchoring protein OlpB was successfully introduced and expressed in K. marxianus cells by Anandharaj and coworkers [73].…”

Bioprocesses with Reduced Ecological Footprint by Marine Debaryomyces hansenii Strain for Potential Applications in Circular Economy

“…Recently, marine yeasts have been explored as source of enzymes useful in bioprocesses [7][8][9][10]. The salt tolerance showed by these enzymes makes them more resistant to industrial bioprocess conditions [40].…”

“…This is also true of their enzymes, which present features often more suitable for developing bioconversions. For these reasons, marine yeasts have great potential to be applied in industrial biotechnological processes [7][8][9][10].…”