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Mendoza Beltran Angelica Scheel Claus Nordstrøm Fitton Nuala Schmidt Jannick Kløverpris Jesper Hedal 《The International Journal of Life Cycle Assessment》2021,26(8):1570-1585
The International Journal of Life Cycle Assessment - To estimate life cycle impacts from introducing the yield-enhancing inoculant containing the nitrogen-fixing bacterium Bradyrhizobium japonicum... 相似文献
2.
Lars Milke Patrícia Ferreira Nicolai Kallscheuer Adelaide Braga Michael Vogt Jannick Kappelmann Joana Oliveira Ana Rita Silva Isabel Rocha Michael Bott Stephan Noack Nuno Faria Jan Marienhagen 《Biotechnology and bioengineering》2019,116(6):1380-1391
In recent years microorganisms have been engineered towards synthesizing interesting plant polyphenols such as flavonoids and stilbenes from glucose. Currently, the low endogenous supply of malonyl-CoA, indispensable for plant polyphenol synthesis, impedes high product titers. Usually, limited malonyl-CoA availability during plant polyphenol production is avoided by supplementing fatty acid synthesis-inhibiting antibiotics such as cerulenin, which are known to increase the intracellular malonyl-CoA pool as a side effect. Motivated by the goal of microbial polyphenol synthesis being independent of such expensive additives, we used rational metabolic engineering approaches to modulate regulation of fatty acid synthesis and flux into the tricarboxylic acid cycle (TCA cycle) in Corynebacterium glutamicum strains capable of flavonoid and stilbene synthesis. Initial experiments showed that sole overexpression of genes coding for the native malonyl-CoA-forming acetyl-CoA carboxylase is not sufficient for increasing polyphenol production in C. glutamicum. Hence, the intracellular acetyl-CoA availability was also increased by reducing the flux into the TCA cycle through reduction of citrate synthase activity. In defined cultivation medium, the constructed C. glutamicum strains accumulated 24 mg·L −1 (0.088 mM) naringenin or 112 mg·L −1 (0.49 mM) resveratrol from glucose without supplementation of phenylpropanoid precursor molecules or any inhibitors of fatty acid synthesis. 相似文献
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Optimizing expression and purification from cell culture medium of trispecific recombinant antibody derivatives 总被引:3,自引:0,他引:3
Willems A Leoen J Schoonooghe S Grooten J Mertens N 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,786(1-2):161-176
Antibody fragments offer the possibility to build multifunctional manifolds tailored to meet a large variety of needs. We optimized the production of a manifold consisting of one (bibody) or two (tribody) single-chain variable fragments coupled to the C-terminus of Fab chains. Different strong mammalian promoters were compared and the influence of expression media on production and recovery was investigated. Since the physical and chemical nature of these molecules largely depends on the nature of the antibody building blocks incorporated, a generally applicable process for the purification of recombinant antibody derivatives from serum containing mammalian cell culture medium was designed. To this end we compared protein L, hydroxyapatite, immobilized metal affinity chromatography, cation-exchange chromatography and hydrophobic charge induction chromatography. 相似文献
4.
Jannick Van Cauwenberghe Rosa I. Santamaría Patricia Bustos Soledad Jurez Maria Antonella Ducci Trinidad Figueroa Fleming Angela Virginia Etcheverry Víctor Gonzlez 《The ISME journal》2021,15(7):2092
Bacteriophages play significant roles in the composition, diversity, and evolution of bacterial communities. Despite their importance, it remains unclear how phage diversity and phage-host interactions are spatially structured. Local adaptation may play a key role. Nitrogen-fixing symbiotic bacteria, known as rhizobia, have been shown to locally adapt to domesticated common bean at its Mesoamerican and Andean sites of origin. This may affect phage-rhizobium interactions. However, knowledge about the diversity and coevolution of phages with their respective Rhizobium populations is lacking. Here, through the study of four phage-Rhizobium communities in Mexico and Argentina, we show that both phage and host diversity is spatially structured. Cross-infection experiments demonstrated that phage infection rates were higher overall in sympatric rhizobia than in allopatric rhizobia except for one Argentinean community, indicating phage local adaptation and host maladaptation. Phage-host interactions were shaped by the genetic identity and geographic origin of both the phage and the host. The phages ranged from specialists to generalists, revealing a nested network of interactions. Our results suggest a key role of local adaptation to resident host bacterial communities in shaping the phage genetic and phenotypic composition, following a similar spatial pattern of diversity and coevolution to that in the host.Subject terms: Microbial ecology, Bacteriophages, Microbial ecology, Biogeography, Microbial communities 相似文献
5.
Henrik Lund Brian Vad Mathiesen Per Christensen Jannick Hoejrup Schmidt 《The International Journal of Life Cycle Assessment》2010,15(3):260-271
Background, aim and scope
This paper discusses the identification of the environmental consequences of marginal electricity supplies in consequential life cycle assessments (LCA). According to the methodology, environmental characteristics can be examined by identifying affected activities, i.e. often the marginal technology. The present ‘state-of the-art’ method is to identify the long-term change in power plant capacity, known as the long-term marginal technology, and assume that the marginal supply will be fully produced at such capacity. However, the marginal change in capacity will have to operate as an integrated part of the total energy system. Consequently, it does not necessarily represent the marginal change in electricity supply, which is likely to involve a mixture of different production technologies. Especially when planning future sustainable energy systems involving combined heat and power (CHP) and fluctuating renewable energy sources, such issue becomes very important. 相似文献6.
Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88 总被引:1,自引:0,他引:1
Pel HJ de Winde JH Archer DB Dyer PS Hofmann G Schaap PJ Turner G de Vries RP Albang R Albermann K Andersen MR Bendtsen JD Benen JA van den Berg M Breestraat S Caddick MX Contreras R Cornell M Coutinho PM Danchin EG Debets AJ Dekker P van Dijck PW van Dijk A Dijkhuizen L Driessen AJ d'Enfert C Geysens S Goosen C Groot GS de Groot PW Guillemette T Henrissat B Herweijer M van den Hombergh JP van den Hondel CA van der Heijden RT van der Kaaij RM Klis FM Kools HJ Kubicek CP van Kuyk PA Lauber J 《Nature biotechnology》2007,25(2):221-231
7.
We present here a neural network based method for prediction of N-terminal acetylation-by far the most abundant post-translational modification in eukaryotes. The method was developed on a yeast dataset for N-acetyltransferase A (NatA) acetylation, which is the type of N-acetylation for which most examples are known and for which orthologs have been found in several eukaryotes. We obtain correlation coefficients close to 0.7 on yeast data and a sensitivity up to 74% on mammalian data, suggesting that the method is valid for eukaryotic NatA orthologs. 相似文献
8.
Michele De Rosa Jannick Schmidt Miguel Brandão Massimo Pizzol 《The International Journal of Life Cycle Assessment》2017,22(2):172-184
Purpose
Despite a mature debate on the importance of a time-dependent account of carbon fluxes in life cycle assessments (LCA) of forestry products, static accounts of fluxes are still common. Time-explicit inventory of carbon fluxes is not available to LCA practitioners, since the most commonly used life cycle inventory (LCI) databases use a static approach. Existing forest models are typically applied to specific study fields for which the detailed input parameters required are available. This paper presents a simplified parametric model to obtain a time-explicit balanced account of the carbon fluxes in a forest for use in LCA. The model was applied to the case of spruce as an example.Methods
The model calculated endogenous and exogenous carbon fluxes in tons of carbon per hectare. It was designed to allow users to choose (a) the carbon pools to be included in the analysis (aboveground and belowground carbon pools, only aboveground carbon or only carbon in stem); (b) a linear or sigmoidal dynamic function describing biomass growth; (c) a sigmoidal, negative exponential or linear dynamic function describing independently the decomposition of aboveground and belowground biomass; and (d) the forest management features such as stand type, rotation time, thinning frequency and intensity.Results and discussion
The parametric model provides a time-dependent LCI of forest carbon fluxes per unit of product, taking into account the typically limited data available to LCA practitioners, while providing consistent and robust outcomes. The results obtained for the case study were validated with the more complex CO2FIX. The model ensures carbon balance within spatial and time delimitation defined by the user by accounting for the annual biomass degradation and production in each carbon pool. The inventory can be used in LCA studies and coupled with classic indicators (e.g. global warming potential) to accurately determine the climate impacts over time. The model is applicable globally and to any forest management practice.Conclusions
This paper proposes a simplified and flexible forest model, which facilitates the implementation in LCA of time-dependent assessments of bio-based products.9.
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