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Development of fungal cell factories for the production of secondary metabolites:Linking genomics and metabolism

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Synthetic and Systems Biotechnology 2017年第1期2卷 5-12页

作者： Jens Christian nielsen Jens nielsen Chalmers University of Technology Kemivagen 10Sweden

The genomic era has revolutionized research on secondary metabolites and bioinformatics methods have in recent years revived the antibiotic discovery process after decades with only few new active molecules being *** computational tools are driven by genomics and metabolomics analysis,and enables rapid identification of novel secondary *** translate this increased discovery rate into industrial exploitation,it is necessary to integrate secondary metabolite pathways in the metabolic engineering *** this review,we will describe the novel advances in discovery of secondary metabolites produced by filamentous fungi,highlight the utilization of genome-scale metabolic models(GEMs)in the design of fungal cell factories for the production of secondary metabolites and review strategies for optimizing secondary metabolite production through the construction of high yielding platform cell factories.

关键词： Secondary metabolism Fungi Biosynthetic gene clusters Genome mining Metabolic modeling Cell factories

New exotic charmonium states

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Chinese Physics C 2010年第9期34卷 1157-1162页

作者： M.nielsen Instituto de Física Universidade de So Paulo

In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the stru... 详细信息

关键词： non-perturbative methods heavy mesons spectroscopy exotic mesons

Plant exocytosis: Weaving distinct pathways to the plant plasma membrane

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Molecular Plant 2022年第3期15卷 382-384页

作者： Erik nielsen Department of Molecular Cellularand Developmental BiologyUniversity of MichiganAnn ArborMI 48109USA

During plant growth and development newly synthesized proteins and other cargo molecules must be selectively targeted to a variety of cellular *** the most important targeting involves the trafficking of proteins to the plasma membrane,where they control interactions with the environment and neighboring *** this process,proteins entering the secretory pathway are imported into the endoplasmic reticulum where they are folded and *** are then sorted and delivered to the Golgi complex,where they are further processed and modified.

关键词： neighboring processed complex

Targeting and Regulation of Cell Wall Synthesis During Tip Growth in Plants

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Journal of Integrative Plant Biology 2013年第9期55卷 835-846页

作者： Fangwei Gu Erik nielsen Department of Molecular Cellular and Developmental Biology University of MichiganAnn Arbor Michigan 48109 USA

Root hairs and pollen tubes are formed through tip growth, a process requiring synthesis of new cell wall material and the precise targeting and integration of these components to a selected apical plasma membrane domain in the growing tips of these cells. Presence of a tip-focused calcium gradient, control of actin cytoskeleton dynamics, and formation and targeting of secretory vesicles are essential to tip growth. Similar to cells undergoing diffuse growth, cellulose, hemi-celluloses, and pectins are also deposited in the growing apices of tip-growing cells. However, differences in the manner in which these cell wall components are targeted and inserted in the expanding portion of tip-growing cells is reflected by the identification of elements of the plant cell wall synthesis machinery which have been shown to play unique roles in tip-growing cells. In this review, we summarize our current understanding of the tip growth process, with a particular focus on the subcellular targeting of newly synthesized cell wall components, and their roles in this form of plant cell expansion.

关键词： Cellulose membrane trafficking plant cell wall pollen tube root hair tip growth.

Forming Process of Strong Anisotropic Material Based on the Hydrodynamic Deep Drawing with Radial Pressure

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Journal of Materials Science & Technology 2005年第5期21卷 733-737页

作者： Joachim DANCKERT Karl Brian nielsen Department of Production Aalborg University Fibigerstraede 16 DK-9220Aalborg DenmarkDepartment of ProductionAalborg University Fibigerstraede 16 DK-9220Aalborg Denmark

The hydrodynamic deep drawing process enables net shape or near net shape forming of complicated sheet metal parts made from difficultly forming materials, such as aluminium or high strength steels. Based on the conventional hydrodynamic deep drawing process, a new process, hydrodynamic deep drawing process, in which radial pressure is applied to the rim of the blank, is proposed. This new process has been analysed using FEM simulations and the obtained results have been compared with the experimental results. The material used in the experiments was Al-Mg-Si alloy, and in the FEM-simulations the elastic-plastic behaviour of Al-Mg-Si alloy was modelled using Barlat＇s 89 yield criteria.

关键词： Hydroforming Hydrodynamic deep draw Simulation Aluminum alloy

Shot-noise limited, supercontinuum-based optical coherence tomography

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Light(Science & Applications) 2021年第7期10卷 1372-1384页

作者： Shreesha Rao D.S. Mikkel Jensen Lars Grüner-nielsen Jesper Toft Olsen Peter Heiduschka Björn Kemper Jürgen Schnekenburger Martin Glud Mette Mogensen Niels Møller Israelsen Ole bang DTU Fotonik Dept.of Photonics EngineeringTechnical University of DenmarkØrsteds Plads2800 Kongens LyngbyDenmark NKT Photonics A/S Blokken 843460 BirkerødDenmark Department of Ophthalmology University of Münster Medical CentreDomagkstr.15D-48149 MünsterGermany Biomedical Technology Center of the Medical Faculty University of MünsterMendelstr.17D-48149 MünsterGermany Department of Dermatology Bisbebjerg HospitalUniversity of CopenhagenBispebjerg Bakke 232400 Copenhagen NVDenmark

We present the first demonstration of shot-noise limited supercontinuum-based spectral domain optical coherence tomography(SD-OCT)with an axial resolution of 5.9μm at a center wavelength of 1370 *** supercontinuumbased SD-OCT systems cannot be operated in the shot-noise limited detection regime because of severe pulse-topulse relative intensity noise of the supercontinuum *** overcome this disadvantage,we have developed a low-noise supercontinuum source based on an all-normal dispersion(ANDi)fiber,pumped by a femtosecond *** noise performance of our 90 MHz ANDi fiber-based supercontinuum source is compared to that of two commercial sources operating at 80 and 320 MHz repetition *** show that the low-noise of the ANDi fiber-based supercontinuum source improves the OCT images significantly in terms of both higher contrast,better sensitivity,and improved *** SD-OCT imaging of skin,retina,and multilayer stacks we conclude that supercontinuumbased SD-OCT can enter the domain of shot-noise limited detection.

关键词： fiber optical pumped

Coupling of Pi2 wave energy in the inner magnetosphere as inferred from low-latitude ground observations

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Science China(Technological Sciences) 2008年第10期51卷 1745-1758页

作者： C. P. nielsen Norwegian Polar Institute Ny lesund N-9173 Norway

Taking advantage of high time-resolution (1 s) geomagnetic field measurements obtained at low-latitude stations, we investigated frequency differences of Pi2 pul-sations between the dayside and the nightside. Firstly, we examined two Pi2 cases globally observed by multiple ground stations and found that the dominant fre-quency peaks at the dayside showed latitudinal dependence, i.e., the higher (lower) frequency peak was predominant at lower (higher) latitude. We also noticed that the dominant Pi2 frequency on the nightside was apparently higher than that on the dayside. We argue that the multiple frequency peaks observed on the ground are harmonics of a plasmaspheric cavity resonance mode (CRM) and that the latitu-dinal dependence of the dominant frequency peaks may result from the energy coupling between the CRM and field line resonance (FLR) occurred in the near Earth space. We also argue that the frequency difference between the dayside and the nightside could be caused by the reason that a higher harmonic was observed in the nightside plasmasphere but was not effectively observed in the dayside. In addition, we statistically examined 829 Pi2 events that were simultaneously re-corded at Kakioka (KAK, Maglat=27.2°) and Jicamarca (JIC, Maglat=0.0°), the two stations separated by ～10 h in local time (LT) and one of them (JIC) is located at the dip equator. We found that the Pi2 frequency observed at KAK on the nightside was higher than that observed at JIC on the dayside on average. After investigating the occurrence histogram of the frequency difference (△f=fJIC-fKAK) for the events si-multaneously observed at KAK and JIC, we found that close to half of the events had the identical frequency (|△f |<1.0 mHz). The statistical results are consistent with the facts reflected by case studies.

关键词： cavity resonance mode global Pi2 wave energy coupling

Impacts of prenatal nutrition on animal production and performance： a focus on growth and metabolic and endocrine function in sheep

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Journal of Animal Science and Biotechnology 2018年第1期9卷 10-23页

作者： Prabhat Khanal Mette Olaf nielsen Department of Veterinary and Animal Sciences Faculty of Health and Medical SciencesUniversity of Copenhagen Gronnegardsvey 31st floorDK-1870 Frederiksberg CDenmark Department of Nutrition Faculty of MedicineTransgenic Animal and Lipid StorageNorwegian Transgenic Centre(NTS)University of OsloOsloNotway

The concept of foetal programming（FP） originated from human epidemiological studies, where foetal life nutrition was linked to health and disease status later in life. Since the proposal of this phenomenon, it has been evaluated in various animal models to gain further insights into the mechanisms underlying the foetal origins of health and disease in humans. In FP research, the sheep has been quite extensively used as a model for humans. In this paper we will review findings mainly from our Copenhagen sheep model, on the implications of late gestation malnutrition for growth, development, and metabolic and endocrine functions later in life, and discuss how these implications may depend on the diet fed to the animal in early postnatal life. Our results have indicated that negative implications of foetal malnutrition, both as a result of overnutrition and, particularly, late gestation undernutrition, can impair a wide range of endocrine functions regulating growth and presumably also reproductive traits. These implications are not readily observable early in postnatal life, but are increasingly manifested as the animal approaches adulthood. No intervention or cure is known that can reverse this programming in postnatal life. Our findings suggest that close to normal growth and slaughter results can be obtained at least until puberty in animals which have undergone adverse programming in foetal life, but manifestation of programming effects becomes increasingly evident in adult *** to the risk of transfer of the adverse programming effects to future generations, it is therefore recommended that animals that are suspected to have undergone adverse FP are not used for reproduction. Unfortunately, no reliable biomarkers have as yet been identified that allow accurate identification of adversely programmed offspring at birth,except for very low or high birth weights, and, in pigs, characteristic changes in head shape（dolphin head）. Future efforts should be therefo

关键词： Adipose tissue Endocrine function Foetal programming Metabolic function Sheep

Full scale amendment of a contaminated wood impregnation site with iron water treatment residues

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Frontiers of Environmental Science & Engineering 2016年第4期10卷 169-178页

作者： Sanne Skov nielsen Peter KJELDSEN Rasmus JAKOBSEN Orbicon Ringstedvej 20 DK-4000 Roskilde Denmark Department of Environmental Engineering Technical University of Denmark Miljovej 113 DK-2800 Kgs. Lyngby Denmark Geological Survey of Denmark and Greenland Geological Survey of Denmark and Greenland Oster Voldgade 10 DK-1350 Copenhagen K Denmark

Iron water treatment residues （Fe-WTR） are a free by-product of the treatment of drinking water with high concentration of iron oxides and potential for arsenic sorption. This paper aims at applying Fe- WTR to a contaminated site, measuring the reduction in contaminant leaching, and discussing the design of delivery and mixing strategy for soil stabilization at field scale and present a cost-effective method of soil mixing by connnon contractor machinery. Soil contaminated by As, Cr, and Cu at an abandoned wood impregnation site was amended with 0.22% （dw） Fe-WTR. To evaluate the full scale amendment a 100 mtest site and a control site （without amendment） were monitored for 14 months. Also soil analysis of Fe to evaluate the degree of soil and Fe-WTR mixing was done. Stabilization with Fe-WTR had a significant effect on leachable contaminants, reducing pore water As by 93%, Cu by 91% and Cr by 95% in the upper samplers. Dosage and mixing of Fe-WTR in the soil proved to be difficult in the deeper part of the field, and Pire water concentrations of arsenic was generally *** water logged conditions no increase in dissolved iron or arsenic was observed in the amended soil. Our field scale amendment of contaminated soil was overall successful in decreasing leaching of As, Cr and Cu. With minor improvements in the mixing and delivery strategy, this stabilization method is suggested for use in cases, where leaching ofCu, Cr and As constitutes a risk for groundwater and freshwater.

关键词： Field experiment Iron oxide Arsenic Stabilization Wood preservation sites