Model-based biotechnological potential analysis of Kluyveromyces marxianus central metabolism

Funding Information: The research was supported by ERDF project Nr. 2DP/2.1.1.1.0/14/APIA/VIAA/043. Publisher Copyright: © 2017, Society for Industrial Microbiology and Biotechnology.The non-conventional yeast Kluyveromyces marxianus is an emerging industrial producer for many biotechnological processes. Here, we show the application of a biomass-linked stoichiometric model of central metabolism that is experimentally validated, and mass and charge balanced for assessing the carbon conversion efficiency of wild type and modified K. marxianus. Pairs of substrates (lactose, glucose, inulin, xylose) and products (ethanol, acetate, lactate, glycerol, ethyl acetate, succinate, glutamate, phenylethanol and phenylalanine) are examined by various modelling and optimisation methods. Our model reveals the organism’s potential for industrial application and metabolic engineering. Modelling results imply that the aeration regime can be used as a tool to optimise product yield and flux distribution in K. marxianus. Also rebalancing NADH and NADPH utilisation can be used to improve the efficiency of substrate conversion. Xylose is identified as a biotechnologically promising substrate for K. marxianus.publishersversionPeer reviewe

Categorisation of Ancillary Services for Providers

The focus of the work presented here is to raise awareness of how ancillary services within the NordPool area could be of value in supporting the future grid, and who could be the provider of these services. The ancillary services considered here are not limited to the current market, but also services for future market solutions as well as services for fulfilment of grid codes. The goal is to promote the development of existing and novel solutions to increase the utilisation and thus the value of equipment within the power system. The paper includes a techno-economical categorisation of ancillary services, from a provider\u27s perspective, presenting opportunities and competition. Furthermore, procurers of services could utilise this kind of categorisation to identify possible providers or partners. The analysis of the categorisation shows a broad range of possible providers for each service and a broad range of possible services from each provider

Model based biotechnological potential analysis of Kluyveromyces marxianus central metabolism

The non-conventional yeast Kluyveromyces marxianus is an emerging industrial producer for many biotechnological processes. Here we show the application of a biomass-linked stoichiometric model of central metabolism that is experimentally validated, and mass and charge balanced for assessing the carbon conversion efficiency of wild type and modified K. marxianus. Pairs of substrates (lactose, glucose, inulin, xylose) and products (ethanol, acetate, lactate, glycerol, ethyl acetate, succinate, glutamate, phenylethanol and phenylalanine) are examined by various modeling and optimisation methods. Our model reveals the organism's potential for industrial application and metabolic engineering. Modeling results imply that the aeration regime can be used as a tool to optimise product yield and flux distribution in K. marxianus. Also rebalancing NADH and NADPH utilisation can be used to improve the efficiency of substrate conversion. Xylose is identified as a biotechnologically promising substrate for K. marxianus

Electric Consumption Assessment using Smart Meter Data and KPI Methodology

In the modern world, many cities make use of state-of-the-art technologies for a diversity of applications. A field with very specific needs is the electric power system that deals with both large entities that govern themselves (grid operators) and the citizens. For both and all actors in between, there is an increased need for information. Steps to provide these data are always taken and several initiatives are ongoing across the world to equip residential users with last generation smart meters. However, a full deployment is still not possible. Considering this aspect, the authors propose KPIs for the specific situation when some information is available from the meters and other sources, but some is not. The study case is based on a residential area occupied mainly by university students and after an extensive measurement campaign the results have been studied and analysis methods proposed

Energy Management Modelling Under Real-time Approach

The paper describes modelling, design and testing of the developed Energy Management Strategy (EMS) system simulation model. The project was carried out by NTNU and IPE contributing to CloudGrid, with the aim to develop a new real-time simulation model with price-based Demand Response (DR) program for future implementation as consumer flexibility tool. Real load data were used as the basis of the model that was tested in Real-time Simulator in Norwegian National Smart Grid Laboratory at NTNU, with an algorithm and measurements provided from IPE member side

ENGINEERING FOR RURAL DEVELOPMENT KINETIC MODELING OF ETHANOL FERMENTATION BY YEAST KLUYVEROMYCES MARXIANUS FROM LACTOSE-AND INULIN-CONTAINING SUBSTRATES

Abstract. An unstructured kinetic model was developed in this study for the batch production of bioethanol by the yeast Kluyveromyces marxianus DSM 5422 from the renewable sources of agricultural and food processing origin, such as whey permeate or inulin, which include the terms of both substrate and product inhibitions. Experimental data collected from multiple fermentations in bioreactors with three different initial concentrations for each substrate were used to estimate the parameters and to validate the proposed model. The growth of K.marxianus can be expressed by the Haldane-type extended Monod model in combination with the Jerusalimsky term for the non-competitive product inhibition and the Luedeking-Piret equation was adequate to describe the growth-associated formation of ethanol as the target product. The parameters in the models were estimated by minimizing mean-squared errors between the predictions of the models and the experimental data using the differential evolution (DE) algorithm and the L-BFGS-B nonlinear optimization code. In all cases, the model simulation matched well with the fermentation data being confirmed by the high R-squared values (0.984, 0.992 and 0.965 for WP, lactose and inulin, respectively). The kinetic models proposed here can be employed for the development and optimization of the bioethanol production processes from renewable resources