scholarly journals Global metabolic rewiring for improved CO2 fixation and chemical production in cyanobacteria

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Masahiro Kanno ◽  
Austin L. Carroll ◽  
Shota Atsumi
2021 ◽  
Vol 9 (2) ◽  
pp. 431 ◽  
Author(s):  
Daniel A. Norena-Caro ◽  
Tara M. Malone ◽  
Michael G. Benton

Anabaena sp. UTEX 2576 metabolizes multiple nitrogen (N) sources and is deemed a biotechnological platform for chemical production. Cyanobacteria have been identified as prolific producers of biofertilizers, biopolymers, biofuels, and other bioactive compounds. Here, we analyze the effect of different N-sources and Fe availability on the bioproduction of phycobiliproteins and β-carotene. We characterize nutrient demand in modified BG11 media, including data on CO2 fixation rates, N-source consumption, and mineral utilization (e.g., phosphorus (P), and 11 metallic elements). Results suggest that non-diazotrophic cultures grow up to 60% faster than diazotrophic cells, resulting in 20% higher CO2-fixation rates. While the production of β-carotene was maximum in medium with NaNO3, Fe starvation increased the cellular abundance of C-phycocyanin and allophycocyanin by at least 22%. Compared to cells metabolizing NaNO3 and N2, cultures adapted to urea media increased their P, calcium and manganese demands by at least 72%, 97% and 76%, respectively. Variations on pigmentation and nutrient uptake were attributed to changes in phycocyanobilin biosynthesis, light-induced oxidation of carotenoids, and urea-promoted peroxidation. This work presents insights into developing optimal Anabaena culture for efficient operations of bioproduction and wastewater bioremediation with cyanobacteria.


2019 ◽  
Author(s):  
Yoshihide Furuichi ◽  
Shogo Yoshimoto ◽  
Tomohiro Inaba ◽  
Nobuhiko Nomura ◽  
Katsutoshi Hori

<p></p><p>Biofilms are used in environmental biotechnologies including waste treatment and environmentally friendly chemical production. Understanding the mechanisms of biofilm formation is essential to control microbial behavior and improve environmental biotechnologies. <i>Acinetobacter </i>sp. Tol 5 autoagglutinate through the interaction of the long, peritrichate nanofiber protein AtaA, a trimeric autotransporter adhesin. Using AtaA, without cell growth or the production of extracellular polymeric substances, Tol 5 cells quickly form an unconventional biofilm. In this study, we investigated the formation process of this unconventional biofilm, which started with cell–cell interactions, proceeded to cell clumping, and led to the formation of large cell aggregates. The cell–cell interaction was described by DLVO theory based on a new concept, which considers two independent interactions between two cell bodies and between two AtaA fiber tips forming a virtual discontinuous surface. If cell bodies cannot collide owing to an energy barrier at low ionic strengths but approach within the interactive distance of AtaA fibers, cells can agglutinate through their contact. Cell clumping proceeds following the cluster–cluster aggregation model, and an unconventional biofilm containing void spaces and a fractal nature develops. Understanding its formation process would extend the utilization of various types of biofilms, enhancing environmental biotechnologies.</p><p></p>


2019 ◽  
Vol 16 (3) ◽  
pp. 334-351
Author(s):  
A. S. Mavlyanov ◽  
E. K. Sardarbekova

Introduction. The objective of the research is to study the effect of the complex activation of the alumina raw material on the rheological properties of the ceramic mass. In addition, the authors investigate solutions for the application of optimal coagulation structures based on loams and ash together with plastic certificates.Materials and methods. The authors used the local forest like reserves of clay loams at the BashKarasu, ash fields of the Bishkek Central Heating Centre (BTEC) and plasticizer (sodium naphthenate obtained from alkaline chemical production wastes) as fibrous materials. Moreover, the authors defined technological properties of raw materials within standard laboratory methodology in accordance with current GOSTs.Results. The researchers tested plastic durability on variously prepared masses for the choice of optimal structures. The paper demonstrated the plastic durability of complexly activated compounds comparing with non-activated and mechanically activated compounds. The sensitivity coefficient increased the amount of clay loams by mechanically and complexly activated, which predetermined the possibility of intensifying the process of drying samples based on complexly activated masses.Discussion and conclusions. However, mechanical activation of clay material reduces the period of relaxation and increases the elasticity coefficient of ceramic masses by 1.8–3.4 times, meanwhile decreases elasticity, viscosity and the conventional power during molding, which generally worsens the molding properties of the masses. Сomplex activation of ash-clay material decreases the period of relaxation and provides an increase in elasticity, plasticity of ceramic masses by 46–47%, reduction in viscosity by 1.5–2 times, conventional power on molding by 37–122% in comparison with MA clay loams. Ceramic masses based on spacecraft alumina raw materials belong to the SMT with improved rheological properties; products based on them pass through the mouthpiece for 5–7 seconds.


2018 ◽  
Vol 5 (6) ◽  
pp. 3-7 ◽  
Author(s):  
E.S. Popov ◽  
V.I. Gavrilyuk ◽  
N.V. Mukina ◽  
E.T. Kovalev ◽  
I.D. Drozdnik ◽  
...  

2020 ◽  
Vol 309 ◽  
pp. 123400 ◽  
Author(s):  
M. Venkateswar Reddy ◽  
Gopalakrishnan Kumar ◽  
Gunda Mohanakrishna ◽  
Sutha Shobana ◽  
Riyadh I. Al-Raoush

2021 ◽  
Author(s):  
Faezeh Taghavi ◽  
Amir Khojastehnezhad ◽  
Reza Khalifeh ◽  
Maryam Rajabzadeh ◽  
Fahimeh Rezaei ◽  
...  

The first report of the use of an acidic magnetic metal organic framework for the chemical fixation of CO2 as an environmentally friendly reaction.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3083
Author(s):  
Wisam A. Al Isawi ◽  
Gellert Mezei

Anion binding and extraction from solutions is currently a dynamic research topic in the field of supramolecular chemistry. A particularly challenging task is the extraction of anions with large hydration energies, such as the carbonate ion. Carbonate-binding complexes are also receiving increased interest due to their relevance to atmospheric CO2 fixation. Nanojars are a class of self-assembled, supramolecular coordination complexes that have been shown to bind highly hydrophilic anions and to extract even the most hydrophilic ones, including carbonate, from water into aliphatic solvents. Here we present an expanded nanojar that is able to bind two carbonate ions, thus doubling the previously reported carbonate-binding capacity of nanojars. The new nanojar is characterized by detailed single-crystal X-ray crystallographic studies in the solid state and electrospray ionization mass spectrometric (including tandem MS/MS) studies in solution.


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