Optimized expression of the Starmerella bombicola lactone esterase in Pichia pastoris through temperature adaptation, codon-optimization and co-expression with HAC1

The Starmerella bombicola lactone esterase (SBLE) is a novel enzyme that, in vivo, catalyzes the intramolecular esterification (lactonization) of acidic sophorolipids in an aqueous environment. In fact, this is an unusual reaction given the unfavorable conditions for dehydration. This characteristic strongly contributes to the potential of SBLE to become a 'green' tool in industrial applications. Indeed, lactonization occurs normally in organic solvents, an application for which microbial lipases are increasingly used as biocatalysts. Previously, we described the production of recombinant SBLE (rSBLE) in Pichia pastoris (syn. Komagataella phaffii). However, expression was not optimal to delve deeper into the enzyme's potential for industrial application. In the current study, we explored codon-optimization of the SBLE gene and we optimized the rSBLE expression protocol. Temperature reduction had the biggest impact followed by codon-optimization and co-expression of the HAC1 transcription factor. Combining these approaches, we achieved a 32-fold improvement of the yield during rSBLE production (from 0.75 mg/l to 24 mg/L culture) accompanied with a strong reduction of contaminants after affinity purification

Petroselinic acid purification and its use for the fermentation of new sophorolipids

Petroselinic acid, a positional isomer of oleic acid, was isolated from the vegetable oil of Coriandrum sativum fruits. This uncommon fatty acid was subsequently used as substrate for sophorolipid fermentation with a Starmerella bombicola lactone esterase overexpression (oe sble) strain. A petroselinic acid based diacetylated sophorolipid lactone was obtained in high purity without incorporation of de novo synthesized fatty acids such as oleic acid. A total production of 40 g/L was obtained. The petroselinic acid based sophorolipid lactone was subsequently hydrolyzed towards the petroselinic acid based sophorolipid acid. For both compounds, their critical micelle concentration (CMC) and corresponding surface tension were compared to their oleic acid based counterparts. Both petroselinic acid based sophorolipids displayed a much lower CMC value than their oleic acid based counterparts, although their minimal surface tension was the same. Besides, the sophorolipid fermentation product was chemically modified towards a novel C12 sophorolipid aldehyde. This derivative constitutes an interesting building block for further modification towards new-to-nature sophorolipids with high potential for self-assembly applications

FD Mediagroup: Surviving digital disruption

The FD Mediagroep (FDMG) case describes how a leading local, niche newspaper company dealt with the challenges of digital disruption in the period 2011-2020. It describes both the actions taken at the corporate and business unit level and shows how FDMG has strengthened its core media business. Furthermore, the case describes how FDMG grew beyond its media core and unveils how the company decided to manage this new business division, and how it chose its operating model: Should the new business operate as an autonomous division or should the corporation actively pursue synergies with the other business divisions

KBC's digital transformation: a cultural and people change (B)

This is part of a case series. We follow Erik Luts, the responsible for Direct Channels at KBC Belgium. Together with Daniel Falque, CEO of KBC Belgium, and Johan Lema, Senior General Manager Customer Support Retail & Businesses, he has been working to get KBC ready for the digital age. They are leading an organisation-wide transformation to an omni-channel and customer-centric bank and insurance group, relying on new approaches to digitisation. Although the company has made significant progress with the execution of its strategy, there are still significant hurdles to be taken. One of the major hurdles is gaining acceptance of the strategy in the branches, still the main channel of the bank in Belgium

KBC's Digital Transformation: A Strategic Response

This is part of a case series. We follow Erik Luts, the responsible for Direct Channels at KBC Belgium. Together with Daniel Falque, CEO of KBC Belgium, and Johan Lema, Senior General Manager Customer Support Retail & Businesses, he has been working to get KBC ready for the digital age. They are leading an organisation-wide transformation to an omni-channel and customer-centric bank and insurance group, relying on new approaches to digitisation. Although the company has made significant progress with the execution of its strategy, there are still significant hurdles to be taken. One of the major hurdles is gaining acceptance of the strategy in the branches, still the main channel of the bank in Belgium

KBC's digital transformation: a strategic response (A)

This is part of a case series. We follow Erik Luts, the responsible for Direct Channels at KBC Belgium. Together with Daniel Falque, CEO of KBC Belgium, and Johan Lema, Senior General Manager Customer Support Retail & Businesses, he has been working to get KBC ready for the digital age. They are leading an organisation-wide transformation to an omni-channel and customer-centric bank and insurance group, relying on new approaches to digitisation. Although the company has made significant progress with the execution of its strategy, there are still significant hurdles to be taken. One of the major hurdles is gaining acceptance of the strategy in the branches, still the main channel of the bank in Belgium