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Peptide emulsifiers derived from plant proteins are gathering growing interest as green and sustainable replacements for chemical additives in food. Potato (Solanum tuberosum) is one of the most important crops for both human consumption and industrial processing. Globally, the annual production of potato starch exceeds 3,000,000 MT with more than 200,000 MT of potato protein isolated as a side-stream, providing an enormous source of raw protein. The direct isolation of food-grade protein is in many cases regarded as cost-ineffective. Nevertheless, potato proteins may be a valuable source of functional peptides.Previously, we demonstrated amphiphilicity-based bioinformatic prediction of peptide emulsifiers embedded in potato proteins1,2. Amongst the predicted peptides, especially one (γ1), derived from the storage protein patatin, showed exceptional emulsifying activity in vitro. Although patatin is the most abundant protein in potatoes, it is not a single protein, but a family of highly homologous isoforms. Using bottom-up proteomics in combination with multiple sequence alignment and in silico digestion, we identified several γ1 variants. The variants consist of both full-length isoforms with single amino acid substitutions and tryptic variants/truncations from different patatin isoforms. The emulsifying activity of the γ1 variants, physical stability of the emulsions during storage, and interfacial properties were investigated3. Furthermore, the interfacial conformation of the peptides was investigated by SRCD and supplemented by NMR and benchtop CD for selected peptides in micellar model systems. Based on these results, we are able to i) evaluate the full potential of using γ1 variants as peptide emulsifiers in food; ii) provide novel insight on the structure/function relationship of amphipathic, α-helical peptide emulsifiers; iii) combine in vitro functional validation with in silico proteolysis to design a scalable and targeted enzymatic hydrolysis, resulting in a hydrolysate with improved emulsifying properties; and iv) apply the hydrolysates as stabilizers for encapsulation of fish oil for foods.

Additional file 1: Table S1. This table contains the primer sequences of both the primers used for gene-amplification and the primer used for initial sanger-sequencing in fragments of around 700 bp, containing at least 50 bp overlap between each fragment. Table S2. This table contains the different plasmids utilized in the project, both the native plasmids used as expression vectors, but also plasmids purchased containing the synthetically derived codon optimized genes. Figure S1. Phylogenetic tree of the PPTases used in the present study (bold) together with 22 additional published PPTases. Bootstrap values (> 70%) from 1000 replications are indicated at the respective nodes. Figure S2. Predicted structure of sfp/ACP interaction with the CoA and Mg2+ ion highlighted by arrows. Figure S3. Production levels of bikaverin and bostrycoidin in the individual strains (relative to OD at 48 h) in the supernatant and pellets. The mean of the supernatant from BY4743::FvPPT1 was set to 100 for both compounds.

Natural products display a large structural variation and different uses within a broad spectrum of industries. In this study, we investigate the influence of carbohydrates and nitrogen sources on the production and selectivity of production of four different polyketides produced by Fusarium solani, fusarubin, javanicin, bostrycoidin and anhydrofusarubin. We introduce four different carbohydrates and two types of nitrogen sources. Hereafter, a full factorial design was applied using combinations of three levels of sucrose and three levels of the two types of nitrogen. Each combination displayed different selectivity and production yields for all the compounds of interest. Response surface design was utilized to investigate possible maximum yields for the surrounding combinations of media. It was also shown that the maximum yields were not always the ones illustrating high selectivity, which is an important factor for making purification steps easier. We visualized the production over time for one of the media types, illustrating high yields and selectivity.

Fusarium pigmentation is dictated by a set of two polyketide synthase (PKS) gene clusters where one is expressed during mycelial growth and the other during perithecial development. In the vast majority of Fusarium species, perithecial pigmentation relies on the PKS3 gene cluster responsible for biosynthesis of fusarubins and bostrycoidins. In these species, mycelial pigmentation is mediated by bikaverin or aurofusarin. However, the situation is different for F. solani where mycelial pigmentation is controlled by the PKS3 gene cluster, while the less common PKS35 is responsible for the perithecial pigmentation, although no actual compound(s) has ever been associated with the latter. We set out to characterize the polyketide pigments of F. solani. The PKS3 gene cluster of F. solani shares seven genes with the previously characterized clusters in F. graminearum and F. fujikuroi. However, it differs from the previously described clusters by containing additional genes, some with predicted enzymatic function related to secondary metabolism. When we overexpressed the cluster specific transcription factor in F. solani, we observed a massive increase in production of javanicin, bostrycoidin, fusarubin and dihydrofusarubin. In order to investigate the perithecial pigment chemistry we performed heterologous expression of the PKS35 in Saccharomyces cerevisiae, yielding prephenalenone and dehydroxyprephenalenone as the initial polyketide intermediates. Secondly, we overexpressed the local transcription factor gene in F. solani, resulting in a dark green and orange/red phenotype. We identified three new candidate compounds by mass spectrometry. To our surprise, the mutant also produced elevated levels of javanicin and bostrycoidin obscuring the observation and isolation of PKS35-related compounds. Interestingly, this co-expression indicates the regulation of both PKS3 and PKS35 gene clusters is somehow connected. Fusarium pigmentation is dictated by a set of two polyketide synthase (PKS) gene clusters where one is expressed during mycelial growth and the other during perithecial development. In the vast majority of Fusarium species, perithecial pigmentation relies on the PKS3 gene cluster responsible for biosynthesis of fusarubins and bostrycoidins. In these species, mycelial pigmentation is mediated by bikaverin or aurofusarin. However, the situation is different for F. solani where mycelial pigmentation is controlled by the PKS3 gene cluster, while the less common PKS35 is responsible for the perithecial pigmentation, although no actual compound(s) has ever been associated with the latter. We set out to characterize the polyketide pigments of F. solani. The PKS3 gene cluster of F. solani shares seven genes with the previously characterized clusters in F. graminearum and F. fujikuroi. However, it differs from the previously described clusters by containing additional genes, some with predicted enzymatic function related to secondary metabolism. When we overexpressed the cluster specific transcription factor in F. solani, we observed a massive increase in production of javanicin, bostrycoidin, fusarubin and dihydrofusarubin. In order to investigate the perithecial pigment chemistry we performed heterologous expression of the PKS35 in Saccharomyces cerevisiae, yielding prephenalenone and dehydroxyprephenalenone as the initial polyketide intermediates. Secondly, we overexpressed the local transcription factor gene in F. solani, resulting in a dark green and orange/red phenotype. We identified three new candidate compounds by mass spectrometry. To our surprise, the mutant also produced elevated levels of javanicin and bostrycoidin obscuring the observation and isolation of PKS35-related compounds. Interestingly, this co-expression indicates the regulation of both PKS3 and PKS35 gene clusters is somehow connected.

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2020; Aachen 1 Online-Ressource (167 Seiten) : Illustrationen, Diagramme (2020). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2020, In this thesis, BIM is examined as part of the integral planning methodology. Specifically, the BIM goal in this thesis is to develop the thermal-energy simulation of HVAC systems using the harmonized Information Delivery Manual (IDM) and Model View Definition (MVD) method, using various application examples. Based thereon, the requirements for a given software architecture are derived and several data models are interconnected. The connection of the different data models is accomplished via specially defined transformation logics. The approaches based on the object and data level allow the definition of the associated Level of Development (LOD)s. Through these extensive elaborations future tools and methods can be established and tailored according to practical requirements. With the development of an IDM, the goal-oriented modeling is described component by component. In the first step, the user level and the technical level are initially considered separately, but in thesecond step they are considered holistically . At the user level, a process diagram is defined from the perspective of management, coordinators, and modelers. While creating the process diagram, the individual tasks, the sequence of execution, and their interfaces are identified. Within the interfaces, the data and information needed for the exchange is specified. This preliminary work allows the definition of a data exchange requirement model at the technical level. Such a model records not only the method of transmission, but also the type of data and information subject to exchange in the respective interfaces.After this formalization, a MVD will be developed. The purpose of the MVD is to tailor the individual interfaces for future applications. The IDM, in particular the process diagram and the data exchange requirements model, form the basis for the definition of the LODs. The LODs define the coordination of the model versions to be delivered during the course of the collaboration on the building project. The specification of the period-related degrees of each model’s maturity allows the coordination of the project. A loss-free transfer in the different interfaces requires a further specification of the transformation of the data and information in the course of the generated output. For this purpose, the relationship structure of the individual models is examined and a method for the transformationof the different data is presented. The methods and results presented in this thesis were elaborated and examined during the course of the EnEff: BIM research project. This research project, funded by the Federal Ministry for Economic Affairs and Energy, was carried out from the end of 2013 to November 2016 and bears the title:ËnEff: BIM planning and operational optimization of energy-efficient buildings through building information models", with the funding code: 03ET1177A-F. To channel further international activities, this project was bundled and edited together with an international research consortium in the IEA EBC Annex 60: "New generation of computational tools for building and community energy systems based on the Modelica and Functional Mockup Interface standards"coordinated by the Energy and Buildings Communities Program., Published by Aachen