scholarly journals First time β-farnesene production by the versatile bacterium Cupriavidus necator

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Sofia Milker ◽  
Dirk Holtmann
Keyword(s):  
Artemisia Annua ◽  
Scale Up ◽  
Batch Process ◽  
Jet Fuel ◽  
Cupriavidus Necator ◽  
Fuel Additive ◽  
E Coli ◽  
New Synthesis ◽  
Production Host ◽  
First Time

Abstract Background Terpenes are remarkably diverse natural structures, which can be formed via two different pathways leading to two common intermediates. Among those, sesquiterpenes represent a variety of industrially relevant products. One important industrially produced product is β-farnesene as a precursor for a jet fuel additive. So far, microbial terpene production has been mostly limited to known production hosts, which are only able to grow on heterotrophic substrates. Results In this paper, we for the first time describe β-farnesene production by the versatile bacterial host Cupriavidus necator on fructose, which is known to grow hetero- and autotrophically and even in bioelectrochemical systems. We were able to show a growth-dependent production of β-farnesene by expressing the β-farnesene synthase from Artemisia annua in C. necator H16 PHB-4. Additionally, we performed a scale-up in a parallel reactor system with production titers of 26.3 ± 1.3 µM β-farnesene with a fed-batch process. Conclusions The β-farnesene production titers reported in this paper are not in the same range as titers published with known heterotrophic producers E. coli or S. cerevisiae. However, this proof-of-principle study with C. necator as production host opens new synthesis routes toward a sustainable economy and leaves room for further optimizations, which have been already performed with the known production strains.

Cloning and Characterization of a Carotenoid Cleavage Dioxygenase from Artemisia Annua L

2011 ◽  
Vol 108 ◽  
pp. 274-281
Author(s):  
Shuo Qian Liu ◽  
Na Tian ◽  
Zhong Hua Liu ◽  
Jia Nan Huang ◽  
Juan Li
Keyword(s):  
Amino Acid ◽  
Artemisia Annua ◽  
Amino Acid Identity ◽  
Carotenoid Cleavage Dioxygenase ◽  
E Coli ◽  
Acid Protein ◽  
Rapid Amplification ◽  
First Time

In order to discover the formation mechanism of carotenoid derived aroma, which has been wildly used on protection of crop against insect attacks, the full-length cDNA of an Artemisia annua carotenoid cleavage dioxygenase (AaCCD1) was cloned by rapid amplification of cDNA ends. The function of AaCCD1 was characterized by expression of AaCCD1 in a strain of E. coli accumulating carotenoids and enzyme assay in vitro. The completed open read frame of AaCCD1 was 1629 bp and it encoded a 542-amino acid protein with a 77% amino acid identity to Arabidopsis thaliana CCD1, a predicted molecular mass of 61.04 kDa and a pI of 5.8. AaCCD1 efficiently cleaves carotenoids and regulate the formation of terpenoid compounds. This is the first time to report the cloning and identification of carotenoid cleavage dioxygenase from Atemisia annua, which will play a great role on understanding the regulation of volatile compounds.

PENGGUNAAN AIR SUPER KRITIS PADA DEPOLIMERISASI NYLON-12 (BATCH PROCESS)

2018 ◽  
Vol 5 (3) ◽  
Author(s):  
Mohamad Yusman
Keyword(s):  
Supercritical Water ◽  
Scale Up ◽  
Experimental Studies ◽  
Reaction System ◽  
Batch Process ◽  
Chemical Recycling ◽  
Water Decomposition ◽  
Product Distributions ◽  
New Process ◽  
Nylon 12

Water at the supercritical state is a new process for the chemical recycling. At this thermodynamic state i.e. Pc = 218 atmospheres and Tc = 374oC , water behaves very differently from its everyday temperament and it is a very good solvent for organic components. Experimental studies show that supercritical water can decompose hydrocarbons/polymers and produce useful products like 2-Azacyclotridecanone /lactam-1 from Nylon-12 (batch process). The decomposition process itself was carried out in batch reaction system in order to get more information about product distributions, time dependence, and scale-up possibilities.Keywords: supercritical water, decomposition, batch, polymer, hydrocarbon

Direct synthesis of jet fuel range dicycloalkane by the aqueous phase hydrodeoxygenation of polycarbonate

2021 ◽  
Author(s):  
Lulin Wang ◽  
Guangyi Li ◽  
Cong Yu ◽  
Ai-Qin Wang ◽  
Xiaodong Wang ◽  
...  
Keyword(s):  
Aqueous Phase ◽  
Direct Synthesis ◽  
Jet Fuel ◽  
Catalyst Systems ◽  
First Time

For the first time, propane-2,2-diyldicyclohexane, a jet fuel range C15 dicycloalkane was directly produced by the aqueous-phase hydrodeoxygenation (APHDO) of polycarbonate (PC). Among the investigated catalyst systems, a mixture of...

scholarly journals Efficacy of compressed sodium chloride (CSC) against E. coli and Candida auris in minutes and methods improvement for testing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lan N. Truong ◽  
Brayden D. Whitlock
Keyword(s):  
Sodium Chloride ◽  
Improved Method ◽  
Candida Auris ◽  
Antimicrobial Surfaces ◽  
E Coli ◽  
Route Of Transmission ◽  
The World ◽  
Short Time ◽  
First Time ◽  
Time Point

AbstractControlling infections has become one of the biggest problems in the world, whether measured in lives lost or money spent. This is worsening as pathogens continue becoming resistant to therapeutics. Antimicrobial surfaces are one strategy being investigated in an attempt to decrease the spread of infections through the most common route of transmission: surfaces, including hands. Regulators have chosen two hours as the time point at which efficacy should be measured. The objectives of this study were to characterize the new antimicrobial surface compressed sodium chloride (CSC) so that its action may be understood at timepoints more relevant to real-time infection control, under two minutes; to develop a sensitive method to test efficacy at short time points; and to investigate antifungal properties for the first time. E. coli and Candida auris are added to surfaces, and the surfaces are monitored by contact plate, or by washing into collection vats. An improved method of testing antimicrobial efficacy is reported. Antimicrobial CSC achieves at least 99.9% reduction of E. coli in the first two minutes of contact, and at least 99% reduction of C. auris in one minute.

scholarly journals Antimicrobial and Immunomodulating Activities of Two Endemic Nepeta Species and Their Major Iridoids Isolated from Natural Sources

2021 ◽  
Vol 14 (5) ◽  
pp. 414
Author(s):  
Neda Aničić ◽  
Uroš Gašić ◽  
Feng Lu ◽  
Ana Ćirić ◽  
Marija Ivanov ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Food Industry ◽  
Balkan Peninsula ◽  
Antimicrobial Activities ◽  
Natural Sources ◽  
E Coli ◽  
Food Borne ◽  
Metabolite Profiles ◽  
Aspergillus Sp ◽  
First Time

Two Balkan Peninsula endemics, Nepeta rtanjensis and N. argolica subsp. argolica, both characterized by specialized metabolite profiles predominated by iridoids and phenolics, are differentiated according to the stereochemistry of major iridoid aglycone nepetalactone (NL). For the first time, the present study provides a comparative analysis of antimicrobial and immunomodulating activities of the two Nepeta species and their major iridoids isolated from natural sources—cis,trans-NL, trans,cis-NL, and 1,5,9-epideoxyloganic acid (1,5,9-eDLA), as well as of phenolic acid rosmarinic acid (RA). Methanol extracts and pure iridoids displayed excellent antimicrobial activity against eight strains of bacteria and seven strains of fungi. They were especially potent against food-borne pathogens such as L. monocytogenes, E. coli, S. aureus, Penicillium sp., and Aspergillus sp. Targeted iridoids were efficient agents in preventing biofilm formation of resistant P. aeruginosa strain, and they displayed additive antimicrobial interaction. Iridoids are, to a great extent, responsible for the prominent antimicrobial activities of the two Nepeta species, although are probably minor contributors to the moderate immunomodulatory effects. The analyzed iridoids and RA, individually or in mixtures, have the potential to be used in the pharmaceutical industry as potent antimicrobials, and in the food industry to increase the shelf life and safety of food products.

scholarly journals Complete biosynthesis of a sulfated chondroitin in Escherichia coli

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Abinaya Badri ◽  
Asher Williams ◽  
Adeola Awofiranye ◽  
Payel Datta ◽  
Ke Xia ◽  
...  
Keyword(s):  
Chondroitin Sulfate ◽  
Scale Up ◽  
Production Methods ◽  
E Coli ◽  
Microbial Cell Factories ◽  
Cell Factories ◽  
Microbial Product ◽  
Dry Cell Weight ◽  
One Step ◽  
Dry Cell

AbstractSulfated glycosaminoglycans (GAGs) are a class of important biologics that are currently manufactured by extraction from animal tissues. Although such methods are unsustainable and prone to contamination, animal-free production methods have not emerged as competitive alternatives due to complexities in scale-up, requirement for multiple stages and cost of co-factors and purification. Here, we demonstrate the development of single microbial cell factories capable of complete, one-step biosynthesis of chondroitin sulfate (CS), a type of GAG. We engineer E. coli to produce all three required components for CS production–chondroitin, sulfate donor and sulfotransferase. In this way, we achieve intracellular CS production of ~27 μg/g dry-cell-weight with about 96% of the disaccharides sulfated. We further explore four different factors that can affect the sulfation levels of this microbial product. Overall, this is a demonstration of simple, one-step microbial production of a sulfated GAG and marks an important step in the animal-free production of these molecules.

scholarly journals Radical Dehalogenation and Purine Nucleoside Phosphorylase E. coli: How Does an Admixture of 2′,3′-Anhydroinosine Hinder 2-fluoro-cordycepin Synthesis

Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 539
Author(s):  
Alexey L. Kayushin ◽  
Julia A. Tokunova ◽  
Ilja V. Fateev ◽  
Alexandra O. Arnautova ◽  
Maria Ya. Berzina ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Chemical Synthesis ◽  
Purine Nucleoside Phosphorylase ◽  
Purine Nucleoside ◽  
Preparative Synthesis ◽  
Nucleoside Phosphorylase ◽  
E Coli ◽  
First Time

During the preparative synthesis of 2-fluorocordycepin from 2-fluoroadenosine and 3′-deoxyinosine catalyzed by E. coli purine nucleoside phosphorylase, a slowdown of the reaction and decrease of yield down to 5% were encountered. An unknown nucleoside was found in the reaction mixture and its structure was established. This nucleoside is formed from the admixture of 2′,3′-anhydroinosine, a byproduct in the preparation of 3-′deoxyinosine. Moreover, 2′,3′-anhydroinosine forms during radical dehalogenation of 9-(2′,5′-di-O-acetyl-3′-bromo- -3′-deoxyxylofuranosyl)hypoxanthine, a precursor of 3′-deoxyinosine in chemical synthesis. The products of 2′,3′-anhydroinosine hydrolysis inhibit the formation of 1-phospho-3-deoxyribose during the synthesis of 2-fluorocordycepin. The progress of 2′,3′-anhydroinosine hydrolysis was investigated. The reactions were performed in D2O instead of H2O; this allowed accumulating intermediate substances in sufficient quantities. Two intermediates were isolated and their structures were confirmed by mass and NMR spectroscopy. A mechanism of 2′,3′-anhydroinosine hydrolysis in D2O is fully determined for the first time.

scholarly journals Antimicrobial Activity of L-Lysine and Poly-L-Lysine with Pulsed Electric Fields

2021 ◽  
Vol 11 (6) ◽  
pp. 2708
Author(s):  
Jurgita Švedienė ◽  
Vitalij Novickij ◽  
Rokas Žalnėravičius ◽  
Vita Raudonienė ◽  
Svetlana Markovskaja ◽  
...  
Keyword(s):  
Electric Fields ◽  
Pulsed Electric Fields ◽  
Antimicrobial Treatment ◽  
Treatment Development ◽  
E Coli ◽  
Yeast Fungi ◽  
New Treatment ◽  
First Time ◽  
Resistant Microorganism ◽  
Susceptibility Patterns

For the first time, the possibility to use L-lysine (Lys) and poly-L-lysine (PLL) as additives with pulsed electric fields (PEF) for antimicrobial treatment is reported. The antimicrobial efficacy of Lys and PLL for Escherichia coli, Staphylococcus aureus, Trichophyton rubrum and Candida albicans was determined. Inactivation of microorganisms was also studied by combining Lys and PLL with PEF of 15 and 30 kV/cm. For PEF treatment, pulses of 0.5, 1, 10 or 100 μs were applied in a sequence of 10 to 5000 at 1 kHz frequency. The obtained results showed that 100 μs pulses were the most effective in combination with Lys and PLL for all microorganisms. Equivalent energy PEF bursts with a shorter duration of the pulse were less effective independently on PEF amplitude. Additionally, various treatment susceptibility patterns of microorganisms were determined and reported. In this study, the Gram-negative E. coli was the most treatment-resistant microorganism. Nevertheless, inactivation rates exceeding 2 log viability reduction were achieved for all analyzed yeast, fungi, and bacteria. This methodology could be used for drug-resistant microorganism’s new treatment development.

scholarly journals Extrusion Processing of Amaranth and Quinoa into Gluten-Free Snack Foods for Celiac and Gluten-Free Diets

2017 ◽  
Vol 6 (5) ◽  
pp. 107
Author(s):  
Caitlin Gearhart ◽  
Kurt A. Rosentrater
Keyword(s):  
Scale Up ◽  
Food Products ◽  
Poor Quality ◽  
Expansion Ratio ◽  
Gluten Free ◽  
Experimental Conditions ◽  
Snack Foods ◽  
Extrusion Processing ◽  
Nutritional Benefits ◽  
First Time

Because of the growth of gluten intolerance and Celiac disease, there is growing interest in development of gluten-free foods. Beyond just being gluten-free, such foods can also have other positive nutritional benefits to human health. Extrusion processing is commonly used to produce a wide variety of human food products. Gluten-free grains can be a processing challenge, however, due to lack of proper binding, which can lead to poor quality food products. This research explores how extrusion parameters impacted the quality of amaranth- and quinoa-based extrudates. The specific objectives of this project included extruding each of the grains, then measuring extrudate properties, such as color, unit density, expansion ratio, and durability. Both the quinoa and amaranth were extruded as raw grain, as well as ground to 2mm and 1mm particle sizes. Other experimental conditions included moisture contents of 20% and 40% (d.b.), and extruder screw speeds of 50 rpm and 100 rpm. All treatments were successfully extruded, and all extrudates had high quality attributes, making this the first time either quinoa or amaranth was extruded without any binding ingredients. This study provides information useful for commercial scale-up.

scholarly journals Expression of Heterologous Cellulases inThermotogasp. Strain RQ2

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Hui Xu ◽  
Dongmei Han ◽  
Zhaohui Xu
Keyword(s):  
Enzyme Activities ◽  
Bacterial Cells ◽  
Recombinant Enzymes ◽  
Caldicellulosiruptor Saccharolyticus ◽  
Shuttle Vectors ◽  
E Coli ◽  
Chimeric Enzymes ◽  
Coding Regions ◽  
First Time ◽  
Culture Supernatants

The ability ofThermotogaspp. to degrade cellulose is limited due to a lack of exoglucanases. To address this deficiency, cellulase genes Csac_1076 (celA) and Csac_1078 (celB) fromCaldicellulosiruptor saccharolyticuswere cloned intoT.sp. strain RQ2 for heterologous overexpression. Coding regions of Csac_1076 and Csac_1078 were fused to the signal peptide of TM1840 (amyA) and TM0070 (xynB), resulting in three chimeric enzymes, namely, TM1840-Csac_1078, TM0070-Csac_1078, and TM0070-Csac_1076, which were carried byThermotoga-E. colishuttle vectors pHX02, pHX04, and pHX07, respectively. All three recombinant enzymes were successfully expressed inE. coliDH5αandT.sp. strain RQ2, rendering the hosts with increased endo- and/or exoglucanase activities. InE. coli, the recombinant enzymes were mainly bound to the bacterial cells, whereas inT.sp. strain RQ2, about half of the enzyme activities were observed in the culture supernatants. However, the cellulase activities were lost inT.sp. strain RQ2 after three consecutive transfers. Nevertheless, this is the first time heterologous genes bigger than 1 kb (up to 5.3 kb in this study) have ever been expressed inThermotoga, demonstrating the feasibility of using engineeredThermotogaspp. for efficient cellulose utilization.

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