scholarly journals Hydrolytic secretome engineering in Yarrowia lipolytica for consolidated bioprocessing on polysaccharide resources: review on starch, cellulose, xylan, and inulin

2021 ◽  
Vol 105 (3) ◽  
pp. 975-989
Author(s):  
Ewelina Celińska ◽  
Jean-Marc Nicaud ◽  
Wojciech Białas
Keyword(s):  
Yarrowia Lipolytica ◽  
High Efficiency ◽  
Consolidated Bioprocessing ◽  
Genome Mining ◽  
Value Added ◽  
Process Models ◽  
Process Efficiency ◽  
Secretory Proteins ◽  
Microbial Conversion ◽  
Key Points

Abstract Consolidated bioprocessing (CBP) featuring concomitant hydrolysis of renewable substrates and microbial conversion into value-added biomolecules is considered to bring substantial benefits to the overall process efficiency. The biggest challenge in developing an economically feasible CBP process is identification of bifunctional biocatalyst merging the ability to utilize the substrate and convert it to value-added product with high efficiency. Yarrowia lipolytica is known for its exceptional performance in hydrophobic substrates assimilation and storage. On the other hand, its capacity to grow on plant-derived biomass is strongly limited. Still, its high potential to simultaneously overproduce several secretory proteins makes Y. lipolytica a platform of choice for expanding its substrate range to complex polysaccharides by engineering its hydrolytic secretome. This review provides an overview of different genetic engineering strategies advancing development of Y. lipolytica strains able to grow on the following four complex polysaccharides: starch, cellulose, xylan, and inulin. Much attention has been paid to genome mining studies uncovering native potential of this species to assimilate untypical sugars, as in many cases it turns out that dormant pathways are present in Y. lipolytica’s genome. In addition, the magnitude of the economic gain by CBP processing is here discussed and supported with adequate calculations based on simulated process models. Key points • The mini-review updates the knowledge on polysaccharide-utilizing Yarrowia lipolytica. • Insight into molecular bases founding new biochemical qualities is provided. • Model industrial processes were simulated and the associated costs were calculated.

scholarly journals Indicative Marker Microbiome Structures Deduced from the Taxonomic Inventory of 67 Full-Scale Anaerobic Digesters of 49 Agricultural Biogas Plants

2021 ◽  
Vol 9 (7) ◽  
pp. 1457
Author(s):  
Julia Hassa ◽  
Johanna Klang ◽  
Dirk Benndorf ◽  
Marcel Pohl ◽  
Benedikt Hülsemann ◽  
...  
Keyword(s):  
Stable Process ◽  
Process Condition ◽  
Full Scale ◽  
Process Models ◽  
Process Efficiency ◽  
Process Conditions ◽  
Rrna Gene ◽  
General Process ◽  
Specific Distribution ◽  
Biogas Plants

There are almost 9500 biogas plants in Germany, which are predominantly operated with energy crops and residues from livestock husbandry over the last two decades. In the future, biogas plants must be enabled to use a much broader range of input materials in a flexible and demand-oriented manner. Hence, the microbial communities will be exposed to frequently varying process conditions, while an overall stable process must be ensured. To accompany this transition, there is the need to better understand how biogas microbiomes respond to management measures and how these responses affect the process efficiency. Therefore, 67 microbiomes originating from 49 agricultural, full-scale biogas plants were taxonomically investigated by 16S rRNA gene amplicon sequencing. These microbiomes were separated into three distinct clusters and one group of outliers, which are characterized by a specific distribution of 253 indicative taxa and their relative abundances. These indicative taxa seem to be adapted to specific process conditions which result from a different biogas plant operation. Based on these results, it seems to be possible to deduce/assess the general process condition of a biogas digester based solely on the microbiome structure, in particular on the distribution of specific indicative taxa, and without knowing the corresponding operational and chemical process parameters. Perspectively, this could allow the development of detection systems and advanced process models considering the microbial diversity.

scholarly journals Consolidated bioprocessing of lignocellulose for production of glucaric acid by an artificial microbial consortium

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Chaofeng Li ◽  
Xiaofeng Lin ◽  
Xing Ling ◽  
Shuo Li ◽  
Hao Fang
Keyword(s):  
Acid Production ◽  
Microbial Consortium ◽  
Consolidated Bioprocessing ◽  
High Titer ◽  
Value Added ◽  
Superior Performance ◽  
Glucaric Acid ◽  
Practical Applications ◽  
Work Distribution ◽  
Rut C30

Abstract Background The biomanufacturing of d-glucaric acid has attracted increasing interest because it is one of the top value-added chemicals produced from biomass. Saccharomyces cerevisiae is regarded as an excellent host for d-glucaric acid production. Results The opi1 gene was knocked out because of its negative regulation on myo-inositol synthesis, which is the limiting step of d-glucaric acid production by S. cerevisiae. We then constructed the biosynthesis pathway of d-glucaric acid in S. cerevisiae INVSc1 opi1Δ and obtained two engineered strains, LGA-1 and LGA-C, producing record-breaking titers of d-glucaric acid: 9.53 ± 0.46 g/L and 11.21 ± 0.63 g/L d-glucaric acid from 30 g/L glucose and 10.8 g/L myo-inositol in fed-batch fermentation mode, respectively. However, LGA-1 was preferable because of its genetic stability and its superior performance in practical applications. There have been no reports on d-glucaric acid production from lignocellulose. Therefore, the biorefinery processes, including separated hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP) were investigated and compared. CBP using an artificial microbial consortium composed of Trichoderma reesei (T. reesei) Rut-C30 and S. cerevisiae LGA-1 was found to have relatively high d-glucaric acid titers and yields after 7 d of fermentation, 0.54 ± 0.12 g/L d-glucaric acid from 15 g/L Avicel and 0.45 ± 0.06 g/L d-glucaric acid from 15 g/L steam-exploded corn stover (SECS), respectively. In an attempt to design the microbial consortium for more efficient CBP, the team consisting of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be the best, with excellent work distribution and collaboration. Conclusions Two engineered S. cerevisiae strains, LGA-1 and LGA-C, with high titers of d-glucaric acid were obtained. This indicated that S. cerevisiae INVSc1 is an excellent host for d-glucaric acid production. Lignocellulose is a preferable substrate over myo-inositol. SHF, SSF, and CBP were studied, and CBP using an artificial microbial consortium of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be promising because of its relatively high titer and yield. T. reesei Rut-C30 and S. cerevisiae LGA-1were proven to be the best teammates for CBP. Further work should be done to improve the efficiency of this microbial consortium for d-glucaric acid production from lignocellulose.

scholarly journals Quasi-graphitic carbon shell-induced Cu confinement promotes electrocatalytic CO2 reduction toward C2+ products

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ji-Yong Kim ◽  
Deokgi Hong ◽  
Jae-Chan Lee ◽  
Hyoung Gyun Kim ◽  
Sungwoo Lee ◽  
...  
Keyword(s):  
High Efficiency ◽  
Co2 Reduction ◽  
Value Added ◽  
Material Design ◽  
Catalyst System ◽  
Critical Issue ◽  
Reduction Reaction ◽  
Catalyst Design ◽  
Design Strategies ◽  
Faradaic Efficiency

AbstractFor steady electroconversion to value-added chemical products with high efficiency, electrocatalyst reconstruction during electrochemical reactions is a critical issue in catalyst design strategies. Here, we report a reconstruction-immunized catalyst system in which Cu nanoparticles are protected by a quasi-graphitic C shell. This C shell epitaxially grew on Cu with quasi-graphitic bonding via a gas–solid reaction governed by the CO (g) - CO2 (g) - C (s) equilibrium. The quasi-graphitic C shell-coated Cu was stable during the CO2 reduction reaction and provided a platform for rational material design. C2+ product selectivity could be additionally improved by doping p-block elements. These elements modulated the electronic structure of the Cu surface and its binding properties, which can affect the intermediate binding and CO dimerization barrier. B-modified Cu attained a 68.1% Faradaic efficiency for C2H4 at −0.55 V (vs RHE) and a C2H4 cathodic power conversion efficiency of 44.0%. In the case of N-modified Cu, an improved C2+ selectivity of 82.3% at a partial current density of 329.2 mA/cm2 was acquired. Quasi-graphitic C shells, which enable surface stabilization and inner element doping, can realize stable CO2-to-C2H4 conversion over 180 h and allow practical application of electrocatalysts for renewable energy conversion.

scholarly journals Bioproduction of succinic acid from xylose by engineered Yarrowia lipolytica without pH control

2020 ◽  
Author(s):  
Ashish Prabhu ◽  
Rodrigo Ledesma- Amaro ◽  
Carol Sze Ki Lin ◽  
Frederic Coulon ◽  
Vijay kumar Thakur ◽  
...  
Keyword(s):  
Cell Growth ◽  
Carbon Source ◽  
Succinic Acid ◽  
Yarrowia Lipolytica ◽  
Recombinant Strain ◽  
Sole Carbon Source ◽  
Substrate Inhibition ◽  
Biomass Concentration ◽  
Value Added ◽  
Green Economy

Abstract Background Xylose is a most prevalent sugar available in hemicellulose fraction of lignocellulosic biomass (LCB) and of great interest for the green economy. Unfortunately, most of the cell factories cannot inherently metabolize xylose as sole carbon source. Yarrowia lipolytica is a non-conventional yeast to produce industrially important metabolites, and it is able to metabolize a large variety of substrates including both hydrophilic and hydrophobic carbon sources. However, Y. lipolytica lacks effective metabolic pathway for xylose uptake and only scarce information is available on utilization of xylose. For the economically feasible of LCB-based biorefineries, effective utilization of both pentose and hexose sugars is obligatory. Results In the present study, succinic acid (SA) production from xylose by Y. lipolytica was examined. To this end, Y. lipolytica PSA02004 strain was engineered by overexpressing pentose pathway cassette comprising of xylose reductase ( XR ), xylitol dehydrogenase ( XDH ) and xylulose kinase ( XK ) gene. The recombinant strain exhibited a robust growth on xylose as sole carbon source and accumulated SA (3.8 g/L) with a yield of 0.19 g/g in shake flask studies. Substrate inhibition studies revealed a marked negative impact on cell growth and product formation above 60 g/L xylose concentration. The modelling based on inhibition kinetics revealed that Aiba model showed better fit with experimental data, which resulted the correlation coefficient (R 2 ) of 0.82 and inhibition constant (K I ) 88.9 g/L. The batch cultivation of recombinant strain in bioreactor resulted in a maximum biomass concentration of 7.3 g/L and SA titer of 11.2 g/L with the yield of 0.18 g/g. Similar results in term of cell growth and SA production were obtained with xylose-rich hydrolysate derived from sugarcane bagasse. The fed-batch fermentation yielded biomass concentration of 11.8 g/L (OD 600 : 56.1) and SA titer of 22.3 g/L with a gradual decrease in pH below 4.0. Acetic acid was obtained as a main byproduct in all the fermentations. Conclusion The recombinant strain displayed potential bioconversion of xylose to succinic acid. Further this study provided a new insight on conversion of LCB into value-added products. To the best of our knowledge, this is the first study on SA production by Y. lipolytica using xylose as a sole carbon source.

DSM-Based Product Representation for Retirement Process-Based Modularity

2009 ◽  
Author(s):  
Xiaoxia Lai ◽  
John K. Gershenson
Keyword(s):  
Product Design ◽  
Modular Design ◽  
Design Method ◽  
Value Added ◽  
Design Methods ◽  
Process Efficiency ◽  
Modular Architecture ◽  
Product Representation ◽  
Modular Product ◽  
Product Modularity

Researchers have expanded the definition of product modularity from function-based modularity to life-cycle process-based modularity. In parallel, measures of product modularity have been developed as well as corresponding modular product design methods. However, a correct modularity measure and modular design method are not enough to realize modular product design. To apply the measure and design method correctly, product representation becomes an important aspect of modular design and imperative for realizing the promised cost savings of modularity. In this paper, a representation for retirement process-based modular design has been developed. Built upon previous representations for assembly and manufacturing-based product design, the representation includes a process similarity matrix and a process dependency matrix. The retirement process-based similarity is based on the similarity in components’ post-life intents (recycling, reuse, disposal), and either the degree of their material compatibility if the components will be recycled, or their disassembly direction or disassembly tools if they need to be disassembled from each other for retirement. Process similarity within a module leads to increased process efficiency (the elimination of non-value added tasks) from the sharing of tooling/equipment. Retirement process-based dependency is developed based on disassembly difficulty, one aspect of the physical interactions between components. Retiring components together as a module to eliminate disassembly and differential processing and reducing the disassembly difficulty between the modules can increase the efficiency of the retirement process. We have first presented which process elements we should consider for defining retirement process similarity and dependency, and then constructed the respective similarity and dependency factors tables. These tables include similarity and dependency factors, which, along with their quantifications, are used to determine a product’s modular architecture to facilitate the retirement process. Finally, a fishing reel is used to illustrate how to apply these factors tables to generate the similarity and dependency matrices that represent a product for retirement-process based modular design. Using these representations as input to the DSM-based modular design methods, we can achieve a design with a modular architecture that improves the retirement process efficiency and reduces retirement costs.

scholarly journals Impact of overproduced heterologous protein characteristics on physiological response in Yarrowia lipolytica steady-state-maintained continuous cultures

2020 ◽  
Vol 104 (22) ◽  
pp. 9785-9800
Author(s):  
Paulina Korpys-Woźniak ◽  
Piotr Kubiak ◽  
Wojciech Białas ◽  
Ewelina Celińska
Keyword(s):  
Steady State ◽  
Yarrowia Lipolytica ◽  
Heterologous Protein ◽  
Target Protein ◽  
Host Cells ◽  
Synthesis Process ◽  
Secretory Proteins ◽  
Heterologous Proteins ◽  
Glycosylation Pattern ◽  
The Impact

Abstract Overproduction of recombinant secretory proteins triggers numerous physiological perturbations. Depending on a given heterologous protein characteristics, the producer cell is faced with different challenges which lead to varying responses in terms of its physiology and the target protein production rate. In the present study, we used steady-state-maintained Yarrowia lipolytica cells to investigate the impact of different heterologous proteins on the physiological behavior of the host cells. Such an approach allowed to uncouple the impact of the overproduction of a particular protein from the phenomena that result from growth phase or are caused by the heterogeneity of the analyzed populations. Altogether, eight variants of recombinant strains, individually overproducing heterologous proteins of varying molecular weight (27–65 kDa) and reporting activity (enzymatic and fluorescent) were subjected to chemostat cultivations. The steady-state-maintained cells were analyzed in terms of the substrate utilization, biomass and metabolites production, as well as the reporter protein synthesis. Simplified distribution of carbon and nitrogen between the respective products, as well as expression analysis of the heterologous genes were conducted. The here-obtained data suggest that using a more transcriptionally active promoter results in channeling more C flux towards the target protein, giving significantly higher specific amounts and production rates of the target polypeptide, at the cost of biomass accumulation, and with no significant impact on the polyols production. The extent of the reporter protein’s post-translational modifications, i.e., the number of disulfide bonds and glycosylation pattern, strongly impacts the synthesis process. Specific responses in terms of the protein formation kinetics, the gene expression levels, and transcript-to-protein linearity were observed. Key Points • Eight expression systems, producing different reporter proteins were analyzed. • The cells were maintained in steady-state by continuous chemostat culturing. • Protein- and promoter-specific effects were observed.

Effect of charge and deformation parameter on energy extraction in charged non-Kerr black holes

2019 ◽  
Vol 28 (16) ◽  
pp. 2040012
Author(s):  
Rehana Rahim ◽  
Khalid Saifullah
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Deformation Parameter ◽  
High Efficiency ◽  
Process Efficiency ◽  
Energy Extraction ◽  
Penrose Process ◽  
Kerr Black Holes ◽  
Very High

We analyze the charged Johannsen–Psaltis black hole for energy extraction via the Penrose process. Efficiency of the Penrose process is found to be dependent on the deformation parameter of the metric and charge. Doing the calculations numerically, we find that, in the nonextremal limit, presence of charge leads to lesser efficiency than the Kerr. In the extremal cases with negative deformation parameter, charge leads to a very high efficiency, higher than that of the Kerr and Johannsen–Psaltis black holes.

scholarly journals The Efficiency Analysis of National R&D Planning for the Field of Precision Medicine in Korea

2018 ◽  
Vol 4 (3) ◽  
pp. 39 ◽  
Author(s):  
BangRae Lee ◽  
EunSoo Sohn ◽  
DongKyu Won ◽  
WoonDong Yeo ◽  
KwangHoon Kim ◽  
...  
Keyword(s):  
Precision Medicine ◽  
Relative Efficiency ◽  
High Efficiency ◽  
Investment Decision ◽  
Value Added ◽  
Efficiency Analysis ◽  
Government Investment ◽  
Technology Sector ◽  
Investment Decision Making ◽  
Input Variables

Precision medicine has received a lot of attention in recent years and we have not yet found any research cases that apply Data Envelopment Analysis (DEA) to investment decision making in this area. The purpose of this study is to analyze the relative efficiency of candidate technology sectors in order to determine priorities for government investment in precision medicine. The results of the efficiency analysis can be used as an important reference for government policy makers to determine the amount of government investment in the next year for each candidate technology sector. The candidate technology for government investment in precision medicine was decided for 23 sectors based on the data analysis and the opinions of expert committees. This study applies the input-oriented DEA in regard to 23 technology sectors, which is widely used to analyze relative efficiency in terms of inputs versus outputs and to enhance efficiency through the propositional reduction of inputs. The input variables include the government’s research and development (R&D) investment and forward and backward industry linkage effects. The output variables are the employment creation effect, value-added effect, number of Korean patents, and number of Korean papers. Our analysis results show that the 23 technology sectors in precision medicine overall have a high efficiency, with the exception of the biobank technology sector. Therefore, since the Biobank technology sector has strong infrastructure characteristics, it seems to require continuous investment. The efficiency of DEA is high in most precision medicine sectors; therefore, overall, investing in these technologies is expected to yield good benefits.

Mechanical Research with Development of Automatic Handshaking Signal Module for Cross Connecting Cabinet Remote Monitoring Control

2014 ◽  
Vol 540 ◽  
pp. 403-406
Author(s):  
Gin Shan Chen ◽  
Zhi Yuan Chen
Keyword(s):  
Optical Fiber ◽  
High Speed ◽  
High Efficiency ◽  
Low Cost ◽  
Central Office ◽  
Value Added ◽  
Broadband Internet ◽  
Functional Changes ◽  
Fiber To The Home ◽  
Network Transmission

Since the urgent demands for high-speed broadband Internet, facilities originally installed in a unit-central office end are moved to the places close to the users in order to enhance the broadband and overcome the high-frequency attenuation of copper cables, such as cross connecting cabinets (CCC) on streets, and the lines between a unit-central office and CCC are changed to optical fiber cables. Network transmission technology has currently become the generation of optical fiber. To actually promote fiber to the home, the value-added services of high-speed Internet access, VoIP, and multimedia service for users are currently the highlighted telecommunications technology and businesses. Nevertheless, copper cables have been used for a long period of time that it would be costly to completely replace copper cables. Gradually replacing old cables with new ones is considered as the optimal strategy. Without constructing optical fiber lines at different places or completely removing copper cables, Automatic Handshaking Signal Module (AHSM) for a CCC developed in this study is considered economical and simple. It could monitor the signal handshaking through remote control and make structural and functional changes of existing copper-cable cross connecting cabinets for the low-cost and high-efficiency seamless technology transfer.

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