scholarly journals Manipulation of the ATP pool as a tool for metabolic engineering

2015 ◽  
Vol 43 (6) ◽  
pp. 1140-1145 ◽  
Author(s):  
Oliver Hädicke ◽  
Steffen Klamt
Keyword(s):  
Metabolic Engineering ◽  
Product Yield ◽  
Volumetric Productivity ◽  
Special Focus ◽  
Process Performance ◽  
Performance Parameters ◽  
Cofactor Engineering ◽  
Atp Pool ◽  
Fine Tune

Cofactor engineering has been long identified as a valuable tool for metabolic engineering. Besides interventions targeting the pools of redox cofactors, many studies addressed the adenosine pools of microorganisms. In this mini-review, we discuss interventions that manipulate the availability of ATP with a special focus on ATP wasting strategies. We discuss the importance to fine-tune the ATP yield along a production pathway to balance process performance parameters like product yield and volumetric productivity.

scholarly journals Hijacking high-flux metabolic pathways to enhance product yield in metabolic engineering

2017 ◽  
Vol 47 (3) ◽  
pp. 262-270
Author(s):  
Yi ZHENG ◽  
Xin WANG ◽  
A. Zhipeng WANG ◽  
YanHe HUANG ◽  
JinShi LIN
Keyword(s):  
Metabolic Engineering ◽  
Metabolic Pathways ◽  
Product Yield ◽  
High Flux

scholarly journals Engineering cofactor metabolism for improved protein and glucoamylase production in Aspergillus niger

2020 ◽  
Author(s):  
Yu-fei Sui ◽  
Tabea Schütze ◽  
Li-Ming Ouyang ◽  
Hong-zhong Lu ◽  
Peng Liu ◽  
...  
Keyword(s):  
Metabolic Engineering ◽  
Aspergillus Niger ◽  
Gene Copy ◽  
Cell Factory ◽  
Flux Analysis ◽  
Cofactor Engineering ◽  
Nadph Regeneration ◽  
Gene Copies ◽  
Glaa Gene ◽  
Glucoamylase Production

Abstract Background: Nicotinamide adenine dinucleotide phosphate (NADPH) is an important cofactor ensuring intracellular redox balance, anabolism and cell growth in all living systems. Our recent multi-omics analyses of glucoamylase (GlaA) biosynthesis in the filamentous fungal cell factory Aspergillus niger indicated that low availability of NADPH might be a limiting factor for GlaA overproduction. Results: We thus employed the Design-Build-Test-Learn cycle for metabolic engineering to identify and prioritize effective cofactor engineering strategies for GlaA overproduction. Based on available metabolomics and 13C metabolic flux analysis data, we individually overexpressed seven predicted genes encoding NADPH regeneration enzymes under the control of Tet-on gene switch in two A. niger recipient strains, one carrying a single and one carrying seven glaA gene copies, respectively, to test their individual effects on GlaA overproduction. Both strains were selected to understand if a strong pull towards glaA biosynthesis (seven gene copies) mandates a higher NADPH supply compared to the native condition (one gene copy). Detailed analysis of all 14 strains cultivated in shake flask cultures uncovered that overexpression of the gsdA gene (glucose 6-phosphate dehydrogenase), gndA gene (6-phosphogluconate dehydrogenase) and maeA gene (NADP-dependent malic enzyme) supported GlaA production on a subtle (10%) but significant level in the background strain carrying seven glaA gene copies. We thus performed maltose-limited chemostat cultures combining metabolome analysis for these three isolates to characterize metabolic-level fluctuations caused by cofactor engineering. In these cultures, overexpression of either the gndA or maeA gene increased the intracellular NADPH pool by 45% and 66%, and the yield of GlaA by 65% and 30%, respectively. In contrast, overexpression of the gsdA gene had a negative effect on both total protein and glucoamylase production. Conclusions: This data suggests for the first time that increased NADPH availability can indeed underpin protein and especially GlaA production in strains where a strong pull towards GlaA biosynthesis exists. This data also indicates that the highest impact on GlaA production can be engineered on a genetic level by increasing the flux through the reverse TCA cycle ( maeA gene) followed by engineering the flux through the pentose phosphate pathway ( gndA gene). We thus propose that NADPH cofactor engineering is indeed a valid strategy for metabolic engineering of A. niger to improve GlaA production, a strategy which is certainly also applicable to the rational design of other microbial cell factories.

scholarly journals Engineering cofactor metabolism for improved protein and glucoamylase production in Aspergillus niger

2020 ◽  
Author(s):  
Yu-fei Sui ◽  
Tabea Schütze ◽  
Li-Ming Ouyang ◽  
Hong-zhong Lu ◽  
Peng Liu ◽  
...  
Keyword(s):  
Metabolic Engineering ◽  
Aspergillus Niger ◽  
Pentose Phosphate Pathway ◽  
Total Protein ◽  
Tca Cycle ◽  
Pentose Phosphate ◽  
Gene Copy ◽  
Cofactor Engineering ◽  
Gene Copies ◽  
Glucoamylase Production

Abstract Background: Nicotinamide adenine dinucleotide phosphate (NADPH) is an important cofactor ensuring intracellular redox balance, anabolism and cell growth in all living systems. Our recent multi-omics analyses of glucoamylase (GlaA) biosynthesis in the filamentous fungal cell factory Aspergillus niger indicated that low availability of NADPH might be a limiting factor for GlaA overproduction.Results: We thus employed the Design-Build-Test-Learn cycle for metabolic engineering to identify and prioritize effective cofactor engineering strategies for GlaA overproduction. Based on available metabolomics and 13C metabolic flux analysis data, we individually overexpressed seven predicted genes encoding NADPH generation enzymes under the control of Tet-on gene switch in two A. niger recipient strains, one carrying a single and one carrying seven glaA gene copies, respectively, to test their individual effects on GlaA and total protein overproduction. Both strains were selected to understand if a strong pull towards glaA biosynthesis (seven gene copies) mandates a higher NADPH supply compared to the native condition (one gene copy). Detailed analysis of all 14 strains cultivated in shake flask cultures uncovered that overexpression of the gsdA gene (glucose 6-phosphate dehydrogenase), gndA gene (6-phosphogluconate dehydrogenase) and maeA gene (NADP-dependent malic enzyme) supported GlaA production on a subtle (10%) but significant level in the background strain carrying seven glaA gene copies. We thus performed maltose-limited chemostat cultures combining metabolome analysis for these three isolates to characterize metabolic-level fluctuations caused by cofactor engineering. In these cultures, overexpression of either the gndA or maeA gene increased the intracellular NADPH pool by 45% and 66%, and the yield of GlaA by 65% and 30%, respectively. In contrast, overexpression of the gsdA gene had a negative effect on both total protein and glucoamylase production.Conclusions: This data suggests for the first time that increased NADPH availability can indeed underpin protein and especially GlaA production in strains where a strong pull towards GlaA biosynthesis exists. This data also indicates that the highest impact on GlaA production can be engineered on a genetic level by increasing the flux through the pentose phosphate pathway (gndA gene)reverse TCA cycle (maeA gene) followed by engineering the flux through the reverse TCA cycle (maeA gene) pentose phosphate pathway (gndA gene). We thus propose that NADPH cofactor engineering is indeed a valid strategy for metabolic engineering of A. niger to improve GlaA production, a strategy which is certainly also applicable to the rational design of other microbial cell factories.

Monitoring of biofilm reactors using natural fluorescence fingerprints

2003 ◽  
Vol 47 (5) ◽  
pp. 161-167 ◽  
Author(s):  
G. Wolf ◽  
J.S. Almeida ◽  
J.G. Crespo ◽  
M.A.M. Reis
Keyword(s):  
Membrane Bioreactor ◽  
Process Performance ◽  
Performance Parameters ◽  
Biofilm Reactors ◽  
Non Invasive ◽  
On Line ◽  
Natural Fluorescence ◽  
Pattern Recognition Approach ◽  
Biofilm Process

Natural fluorescence as a method to monitor biofilm processes was studied, using the example of an extractive membrane bioreactor for the degradation of 3-chloro-4 methylaniline and 1,2-dichloroethane. Non-invasive, on-line, in-situ 2D fluorometry monitoring was employed to elicit biofilm process status. The fluorescence fingerprints were deconvoluted in a pattern recognition approach using artificial neural networks (ANN) through association with key process performance parameters.

Research of Automatic Multi-Function Flat Tea Frying Machine and Process Performance Parameters

2012 ◽  
Vol 479-481 ◽  
pp. 2595-2599
Author(s):  
Wei Xiao ◽  
Zhou Guang Pan
Keyword(s):  
Expert Assessment ◽  
Process Performance ◽  
Performance Parameters ◽  
Frying Temperature ◽  
Test Analysis ◽  
Frying Process ◽  
Tea Quality ◽  
Machine Structure ◽  
Better Than

Automatic multi-function flat frying machine set crank up the tea, science articles, squash, Hui dry in a multi-functional machine structure, staffing fried tea mimic the mechanism of continuous complete Na, friction, pressure, shaking, turning, etc. frying action, the use of computer systems in the process of tea frying temperature, pressure, dry speed process monitoring; through the frying process performance parameters of the test analysis showed that: the automatic multi-function flat frying machine frying tea tea quality of tea samples close to hand-frying, frying by the expert assessment of mechanical parameters were better than some of the tea hand-frying, with the promotional value.

scholarly journals Receptor–Receptor Interactions and Glial Cell Functions with a Special Focus on G Protein-Coupled Receptors

2021 ◽  
Vol 22 (16) ◽  
pp. 8656
Author(s):  
Diego Guidolin ◽  
Cinzia Tortorella ◽  
Manuela Marcoli ◽  
Chiara Cervetto ◽  
Guido Maura ◽  
...  
Keyword(s):  
Intercellular Communication ◽  
Brain Network ◽  
Synaptic Activity ◽  
Special Focus ◽  
Neuronal Populations ◽  
Cell Functions ◽  
Receptor Complexes ◽  
Receptor Interactions ◽  
G Protein Coupled ◽  
Fine Tune

The discovery that receptors from all families can establish allosteric receptor–receptor interactions and variably associate to form receptor complexes operating as integrative input units endowed with a high functional and structural plasticity has expanded our understanding of intercellular communication. Regarding the nervous system, most research in the field has focused on neuronal populations and has led to the identification of many receptor complexes representing an important mechanism to fine-tune synaptic efficiency. Receptor–receptor interactions, however, also modulate glia–neuron and glia–glia intercellular communication, with significant consequences on synaptic activity and brain network plasticity. The research on this topic is probably still at the beginning and, here, available evidence will be reviewed and discussed. It may also be of potential interest from a pharmacological standpoint, opening the possibility to explore, inter alia, glia-based neuroprotective therapeutic strategies.

scholarly journals Data-Driven Prediction of CRISPR-Based Transcription Regulation for Programmable Control of Metabolic Flux

2017 ◽  
Author(s):  
Jiayuan Sheng ◽  
Weihua Guo ◽  
Christine Ash ◽  
Brendan Freitas ◽  
Mitchell Paoletti ◽  
...  
Keyword(s):  
Metabolic Engineering ◽  
Metabolic Flux ◽  
Target Genes ◽  
Product Yield ◽  
Fine Tuning ◽  
Data Driven ◽  
Gene Expressions ◽  
Guide Rnas ◽  
Directional Control ◽  
Transcription Regulators

AbstractMultiplex and multi-directional control of metabolic pathways is crucial for metabolic engineering to improve product yield of fuels, chemicals, and pharmaceuticals. To achieve this goal, artificial transcriptional regulators such as CRISPR-based transcription regulators have been developed to specifically activate or repress genes of interest. Here, we found that by deploying guide RNAs to target on DNA sites at different locations of genetic cassettes, we could use just one synthetic CRISPR-based transcriptional regulator to simultaneously activate and repress gene expressions. By using the pairwise datasets of guide RNAs and gene expressions, we developed a data-driven predictive model to rationally design this system for fine-tuning expression of target genes. We demonstrated that this system could achieve programmable control of metabolic fluxes when using yeast to produce versatile chemicals. We anticipate that this master CRISPR-based transcription regulator will be a valuable addition to the synthetic biology toolkit for metabolic engineering, speeding up the “design-build-test” cycle in industrial biomanufacturing as well as generating new biological insights on the fates of eukaryotic cells.

Sign in / Sign up

Export Citation Format

Share Document