Increasing uniformity of biosurfactant production in Starmerella bombicola via the expression of chimeric cytochrome P450s

Sophorolipids are one of the best known microbial biosurfactants and are produced by several yeast species. The best studied producer is Starmerella bombicola, a non-pathogenic yeast associated in nature with bumblebees. Sophorolipids are built up of the rare disaccharide sophorose, which is attached to a fatty acid through a glyosidic bound. Sophorolipids produced by S. bombicola mainly contain oleic acid as the incorporated hydrophobic group. Other chain lengths can, to a certain content, be incorporated by feeding the yeast with substrates of alternative chain lengths. However, the efficiency for such substrates is low as compared to the preferred C18 chain length and defined by the substrate specificity of the first enzymatic step in sophorolipid biosynthesis, i.e., the cytochrome P450 enzyme CYP52M1. To increase product uniformity and diversity at the same time, a new strain of S. bombicola was developed that produces sophorolipids with a palmitic acid acyl chain. This was achieved by heterologous expression of the cytochrome P450 cyp1 gene of Ustilago maydis and feeding with palmitic acid. Optimization of the production was done by protein and process engineering

Analysis and optimization of substitution treatment in Belgium (SUBANOP)

Since the Belgian Federal Drug policy note in 2001, a legal framework has been developed for the prescription and administration of opioid substitution treatment (OST). However, until today policymakers and fieldworkers point at various gaps in the knowledge on substitution treatment in Belgium, in particular regarding substitution treatment in settings outside specialized centres, on the characteristics of clients receiving substitution therapy and on challenges and obstacles in the provision of this type of treatment. This research tries to answer these questions by providing an extensive and up-to-date overview of key elements of substitution treatment in Belgium. How is the provision of OST organized in Belgium (availability, types of providers, spread, referral and psychosocial support)? How do the clients receiving OST experience substitution treatment? Which obstacles can be identified and which recommendations can be made to overcome these obstacles? The answers to these questions can be found in this book