Improved production of novel (bola) glycolipid biosurfactants with the yeast Starmerella bombicola through an integrative approach combining genetic engineering and multiomics analyses

Starmerella bombicola is well known for its natural efficient capacity to produce glycolipids sophorolipids (SLs) at high titers (> 200 g/L) and high-volumetric productivities (> 2 g/L h). These traits make this nonpathogenic yeast industrially relevant, resulting in valorization of SLs as microbial biosurfactants by several companies. The efficient glycolipid machinery of S. bombicola has, on the other hand, been employed toward the biosynthesis of novel types of glycolipid biosurfactants. This has resulted in the generation of a battery of novel S. bombicola strains, producing a range of (novel) glycolipids of which an overview is given in the first part of this chapter. The novel glycolipids have varying properties resulting in a diverse valorization potential, which is very promising toward the further development of the bio-based economy. However, some of the novel S. bombicola strains suffer(ed) from decreased glycolipid productivity levels, while the molecular regulation of glycolipid biosynthesis with S. bombicola is yet to be fully elucidated. Our lab has applied several (integrated) -omic strategies to overcome these hurdles, and in some cases, this strategy allowed us to acquire the information required to resolve the productivity decrease, giving rise to efficient production of novel glycolipids. Further determination and integration of -omic datasets and even in-line/in-process determination of specific -omic data is expected to positively impact further developments and follow-up of glycolipid biosurfactant production processes with S. bombicola.