Coproduction of cell-bound and secreted value-added compounds: Simultaneous production of carotenoids and amino acids by Corynebacterium glutamicum

2018 ◽  
Vol 247 ◽  
pp. 744-752 ◽  
Author(s):  
Nadja A. Henke ◽  
Daniela Wiebe ◽  
Fernando Pérez-García ◽  
Petra Peters-Wendisch ◽  
Volker F. Wendisch
Keyword(s):  
Amino Acids ◽  
Corynebacterium Glutamicum ◽  
Value Added ◽  
Simultaneous Production

scholarly journals Metabolic engineering of Corynebacterium glutamicum for producing branched chain amino acids

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Shengzhu Yu ◽  
Bo Zheng ◽  
Zhenya Chen ◽  
Yi-Xin Huo
Keyword(s):  
Amino Acids ◽  
Metabolic Engineering ◽  
Corynebacterium Glutamicum ◽  
Animal Feed ◽  
Feedback Inhibition ◽  
Value Added ◽  
Branched Chain Amino Acids ◽  
High Yield ◽  
Acetohydroxy Acid Synthase ◽  
Branched Chain

Abstract Background Branched chain amino acids (BCAAs) are widely applied in the food, pharmaceutical, and animal feed industries. Traditional chemical synthetic and enzymatic BCAAs production in vitro has been hampered by expensive raw materials, harsh reaction conditions, and environmental pollution. Microbial metabolic engineering has attracted considerable attention as an alternative method for BCAAs biosynthesis because it is environmentally friendly and delivers high yield. Main text Corynebacterium glutamicum (C. glutamicum) possesses clear genetic background and mature gene manipulation toolbox, and has been utilized as industrial host for producing BCAAs. Acetohydroxy acid synthase (AHAS) is a crucial enzyme in the BCAAs biosynthetic pathway of C. glutamicum, but feedback inhibition is a disadvantage. We therefore reviewed AHAS modifications that relieve feedback inhibition and then investigated the importance of AHAS modifications in regulating production ratios of three BCAAs. We have comprehensively summarized and discussed metabolic engineering strategies to promote BCAAs synthesis in C. glutamicum and offer solutions to the barriers associated with BCAAs biosynthesis. We also considered the future applications of strains that could produce abundant amounts of BCAAs. Conclusions Branched chain amino acids have been synthesized by engineering the metabolism of C. glutamicum. Future investigations should focus on the feedback inhibition and/or transcription attenuation mechanisms of crucial enzymes. Enzymes with substrate specificity should be developed and applied to the production of individual BCAAs. The strategies used to construct strains producing BCAAs provide guidance for the biosynthesis of other high value-added compounds.

scholarly journals Engineering Corynebacterium glutamicum for the Efficient Production of 3-Hydroxypropionic Acid from a Mixture of Glucose and Acetate via the Malonyl-CoA Pathway

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 203
Author(s):  
Zhishuai Chang ◽  
Wei Dai ◽  
Yufeng Mao ◽  
Zhenzhen Cui ◽  
Zhiwen Wang ◽  
...  
Keyword(s):  
Corynebacterium Glutamicum ◽  
Value Added ◽  
Acid Synthesis ◽  
Efficient Production ◽  
Endogenous Gene ◽  
Malonyl Coa ◽  
Acetate Accumulation ◽  
Level I ◽  
Coa Reductase ◽  
Hydroxypropionic Acid

3-Hydroxypropionic acid (3-HP) has been recognized as one of the top value-added building block chemicals, due to its numerous potential applications. Over the past decade, biosynthesis of 3-HP via the malonyl-CoA pathway has been increasingly favored because it is balanced in terms of ATP and reducing equivalents, does not require the addition of costly coenzymes, and can utilize renewable lignocellulosic biomass. In this study, gene mcr encoding malonyl-CoA reductase from Chloroflexus aurantiacus was introduced into Corynebacterium glutamicum ATCC13032 to construct the strain Cgz1, which accumulated 0.30 g/L 3-HP. Gene ldhA encoding lactate dehydrogenase was subsequently deleted to eliminate lactate accumulation, but this decreased 3-HP production and greatly increased acetate accumulation. Then, different acetate utilization genes were overexpressed to reuse the acetate, and the best candidate Cgz5 expressing endogenous gene pta could effectively reduce the acetate accumulation and produced 0.68 g/L 3-HP. To enhance the supply of the precursor acetyl-CoA, acetate was used as an ancillary carbon source to improve the 3-HP production, and 1.33 g/L 3-HP could be produced from a mixture of glucose and acetate, with a 2.06-fold higher yield than from glucose alone. Finally, to inhibit the major 3-HP competing pathway-fatty acid synthesis, 10 μM cerulenin was added and strain Cgz5 produced 3.77 g/L 3-HP from 15.47 g/L glucose and 4.68 g/L acetate with a yield of 187 mg/g substrate in 48 h, which was 12.57-fold higher than that of Cgz1. To our best knowledge, this is the first report on engineering C. glutamicum to produce 3-HP via the malonyl-CoA pathway. The results indicate that the innocuous biosafety level I microorganism C. glutamicum is a potential industrial 3-HP producer.

scholarly journals Nutritional Profiling and the Value of Processing By-Products from Gilthead Sea Bream (Sparus aurata)

Marine Drugs ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 101 ◽  
Author(s):  
Mirian Pateiro ◽  
Paulo E. S. Munekata ◽  
Rubén Domínguez ◽  
Min Wang ◽  
Francisco J. Barba ◽  
...  
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Amino Acid ◽  
Mineral Content ◽  
Value Added ◽  
Amino Acid Profile ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Fish Processing ◽  
By Products

Fish processing industries generate a large volume of discards. In order to fulfil with the principles of a sustainable circular economy, it is necessary to maintain aquaculture by-products in the food chain through the production of high-value biomolecules that can be used as novel ingredients. In this study, we try to give value to the gilthead sea bream by-products, evaluating the composition and the nutritional value of the muscle and six discards commonly obtained from the fish processing industry (fishbone, gills, guts, heads, liver, and skin), which represent ≈ 61% of the whole fish. Significant differences were detected among muscle and by-products for fatty acid and amino acid profile, as well as mineral content. The discards studied were rich in protein (10%–25%), showing skin and fishbone to have the highest contents. The amino acid profile reflected the high quality of its protein, with 41%–49% being essential amino acids—lysine, leucine, and arginine were the most abundant amino acids. Guts, liver, and skin were the fattiest by-products (25%–35%). High contents of polyunsaturated fatty acids (PUFAs) (31%–34%), n-3 fatty acids (12%–14%), and eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) (6%–8%) characterized these discards. The head displayed by far the highest ash content (9.14%), which was reflected in the mineral content, especially in calcium and phosphorous. These results revealed that gilthead sea bream by-products can be used as source of value-added products such as protein, oils, and mineral supplements.

Corynebacterium glutamicum as a potent biocatalyst for the bioconversion of pentose sugars to value-added products

2011 ◽  
Vol 93 (1) ◽  
pp. 95-106 ◽  
Author(s):  
Vipin Gopinath ◽  
Anusree Murali ◽  
Kiran S. Dhar ◽  
K. Madhavan Nampoothiri
Keyword(s):  
Corynebacterium Glutamicum ◽  
Value Added ◽  
Pentose Sugars ◽  
Value Added Products

scholarly journals Anaerobic Growth of Corynebacterium glutamicum via Mixed-Acid Fermentation

2015 ◽  
Vol 81 (21) ◽  
pp. 7496-7508 ◽  
Author(s):  
Andrea Michel ◽  
Abigail Koch-Koerfges ◽  
Karin Krumbach ◽  
Melanie Brocker ◽  
Michael Bott
Keyword(s):  
Amino Acids ◽  
Corynebacterium Glutamicum ◽  
Tricarboxylic Acid Cycle ◽  
Model Organism ◽  
Anaerobic Growth ◽  
Efficient Production ◽  
Ph Homeostasis ◽  
Anaerobic Conditions ◽  
Acid Fermentation ◽  
Content Type

ABSTRACTCorynebacterium glutamicum, a model organism in microbial biotechnology, is known to metabolize glucose under oxygen-deprived conditions tol-lactate, succinate, and acetate without significant growth. This property is exploited for efficient production of lactate and succinate. Our detailed analysis revealed that marginal growth takes place under anaerobic conditions with glucose, fructose, sucrose, or ribose as a carbon and energy source but not with gluconate, pyruvate, lactate, propionate, or acetate. Supplementation of glucose minimal medium with tryptone strongly enhanced growth up to a final optical density at 600 nm (OD600) of 12, whereas tryptone alone did not allow growth. Amino acids with a high ATP demand for biosynthesis and amino acids of the glutamate family were particularly important for growth stimulation, indicating ATP limitation and a restricted carbon flux into the oxidative tricarboxylic acid cycle toward 2-oxoglutarate. Anaerobic cultivation in a bioreactor with constant nitrogen flushing disclosed that CO2is required to achieve maximal growth and that the pH tolerance is reduced compared to that under aerobic conditions, reflecting a decreased capability for pH homeostasis. Continued growth under anaerobic conditions indicated the absence of an oxygen-requiring reaction that is essential for biomass formation. The results provide an improved understanding of the physiology ofC. glutamicumunder anaerobic conditions.

scholarly journals Genome-wide association study and population structure analysis of seed-bound amino acids and total protein in watermelon

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12343
Author(s):  
Vijay Joshi ◽  
Padma Nimmakayala ◽  
Qiushuo Song ◽  
Venkata Abburi ◽  
Purushothaman Natarajan ◽  
...  
Keyword(s):  
Amino Acids ◽  
Association Study ◽  
Total Protein ◽  
Free Amino Acids ◽  
Free Amino ◽  
Natural Variation ◽  
Genome Wide Association Study ◽  
Value Added ◽  
Genome Wide Association ◽  
Genome Wide

Background Watermelon seeds are a powerhouse of value-added traits such as proteins, free amino acids, vitamins, and essential minerals, offering a paleo-friendly dietary option. Despite the availability of substantial genetic variation, there is no sufficient information on the natural variation in seed-bound amino acids or proteins across the watermelon germplasm. This study aimed to analyze the natural variation in watermelon seed amino acids and total protein and explore underpinning genetic loci by genome-wide association study (GWAS). Methods The study evaluated the distribution of seed-bound free amino acids and total protein in 211 watermelon accessions of Citrullus spp, including 154 of Citrullus lanatus, 54 of Citrullus mucosospermus (egusi) and three of Citrullus amarus. We used the GWAS approach to associate seed phenotypes with 11,456 single nucleotide polymorphisms (SNPs) generated by genotyping-by-sequencing (GBS). Results Our results demonstrate a significant natural variation in different free amino acids and total protein content across accessions and geographic regions. The accessions with high protein content and proportion of essential amino acids warrant its use for value-added benefits in the food and feed industries via biofortification. The GWAS analysis identified 188 SNPs coinciding with 167 candidate genes associated with watermelon seed-bound amino acids and total protein. Clustering of SNPs associated with individual amino acids found by principal component analysis was independent of the speciation or cultivar groups and was not selected during the domestication of sweet watermelon. The identified candidate genes were involved in metabolic pathways associated with amino acid metabolism, such as Argininosuccinate synthase, explaining 7% of the variation in arginine content, which validate their functional relevance and potential for marker-assisted analysis selection. This study provides a platform for exploring potential gene loci involved in seed-bound amino acids metabolism, useful in genetic analysis and development of watermelon varieties with superior seed nutritional values.

scholarly journals Engineering central pathways for industrial-level D-(-)-acetoin biosynthesis in Corynebacterium glutamicum

2020 ◽  
Author(s):  
Lingxue Lu ◽  
Yufeng Mao ◽  
Mengyun Kou ◽  
Zhenzhen Cui ◽  
Biao Jin ◽  
...  
Keyword(s):  
Corynebacterium Glutamicum ◽  
Citrate Synthase ◽  
Value Added ◽  
Environmentally Friendly ◽  
Product Yield ◽  
Microbial Fermentation ◽  
Near Future ◽  
Optically Pure ◽  
Environmentally Friendly Production ◽  
Competitive Product

Abstract Background: Acetoin, especially the optically pure L-(+)- or D-(-)-enantiomer, is a high-value-added bio-based platform chemical and important potential pharmaceutical intermediate. Over the past decades, intense efforts have been devoted to the production of acetoin through green biotechniques. However, efficient and economical methods for the production of optically pure acetoin enantiomers are rarely reported. Previously, we systematically engineered the GRAS microorganism Corynebacterium glutamicum to efficiently produce D-(-)-acetoin from glucose. Nevertheless, its yield and average productivity were still unsatisfactory for industrial bioprocesses. Results: In this study, cellular carbon fluxes in the acetoin producer CGR6 were further redirected toward acetoin synthesis using several metabolic engineering strategies, including blocking anaplerotic pathways, attenuating key genes of the TCA cycle and integrating additional copies of the alsSD operon into the genome. Among them, the combination of attenuation of citrate synthase and inactivation of phosphoenolpyruvate carboxylase showed a significant synergistic effect on acetoin production. Finally, the optimal engineered strain CGS11 produced a titer of 102.45 g/L acetoin with a yield of 0.419 g/g glucose at a rate of 1.86 g/L/h in a 5 L fermenter. The optical purity of the resulting D-(-)-acetoin surpassed 95%. To the best of our knowledge, this is the highest titer of highly enantiomerically enriched D-(-)-acetoin, together with a competitive product yield and productivity, achieved in a simple, green process without expensive additives or substrates. This process therefore opens the possibility to achieve easy, efficient, economical and environmentally-friendly production of D-(-)-acetoin via microbial fermentation in the near future. Conclusion: To the best of our knowledge, this is the highest titer of highly enantiomerically enriched D-(-)-acetoin, together with a competitive product yield and productivity, achieved in a simple, green processes without expensive additives or substrates. This process therefore opens the possibility to achieve easy, efficient, economical and environmentally-friendly production of D-(-)-acetoin via microbial fermentation in the near future.

Sign in / Sign up

Export Citation Format

Share Document