H2 drives metabolic rearrangements in gas-fermenting Clostridium autoethanogenum

Biotechnology for Biofuels, Journal Year: 2018, Volume and Issue: 11(1)

Published: March 1, 2018

The global demand for affordable carbon has never been stronger, and there is an imperative in many industrial processes to use waste streams make products. Gas-fermenting acetogens offer a potential solution several commercial gas fermentation plants are currently under construction. As energy limits acetogen metabolism, supply of H2 should diminish substrate loss CO2 facilitate production reduced energy-intensive However, the effects on CO-grown have yet be experimentally quantified controlled growth conditions.Here, we quantify supplementation by comparing CO, syngas, high-H2 CO mix using chemostat cultures Clostridium autoethanogenum. Cultures were characterised at molecular level metabolomics, proteomics, analysis, genome-scale metabolic model. CO-limited chemostats operated two steady-state biomass concentrations facilitated co-utilisation H2. We show that strongly impacts distribution with fourfold reduction as (61% vs. 17%) proportional increase flux ethanol (15% 61%). Notably, lowers molar acetate/ethanol ratio fivefold. At level, quantitative proteome analysis showed no obvious changes leading these rearrangements suggesting involvement post-translational regulation. Metabolic modelling availability provided reducing power via oxidation saved redox cells all formate directly Wood-Ljungdahl pathway. Modelling further indicated methylene-THF reductase reaction was ferredoxin conditions. In combination also synthesised through acetaldehyde:ferredoxin oxidoreductase (AOR) activity.Our revealed drives layers metabolism provides novel links between carbon, energy, advancing our understanding conservation acetogens. conclude can substantially efficiency thus feed composition considered important factor developing fermentation-based bioprocesses.

Language: Английский

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Concomitant osmotic and chaotropicity-induced stresses in Aspergillus wentii: compatible solutes determine the biotic window

Current Genetics, Journal Year: 2015, Volume and Issue: 61(3), P. 457 - 477

Published: June 8, 2015

Language: Английский

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Aspergillus penicillioides differentiation and cell division at 0.585 water activity

Environmental Microbiology, Journal Year: 2016, Volume and Issue: 19(2), P. 687 - 697

Published: Nov. 21, 2016

Water availability acts as the most stringent constraint for life on Earth. Thus, understanding water relations of microbial extremophiles is imperative to our ability increase agricultural productivity (e.g., by enhancing processing and turnover dead organic matter in soils arid regions), reduce human exposure mycotoxins buildings food-supply chain, prevent spoilage foods/animal feeds, books, museum specimens artworks better control microbiology industrial fermentations. Only a small number systems can retain activity at <0.710 (ISME J 2015 9: 1333-1351). It has long-been considered that resilient these Xeromyces bisporus, which inhabits sugar-rich substrates (Appl Environ Microbiol 1968 16: 1853-1858). The current study focused germination Aspergillus penicillioides, xerophile also able grow under low humidity saline conditions. Investigations differed from those reported earlier: firstly, aerially borne conidia were harvested, then used inoculations, their dry condition; secondly, cultures incubated 24°C, i.e. below optimum temperature, minimize possibility loss substrate; thirdly, remained sealed throughout 73-day period (microscopic examination was carried out directly 48 through Petri plate lid); fourthly, parameters determined were: rates extent conidial swelling, production differentiated germination-structures septate germlings, subsequent development mycelium and/or sporulation; fifthly, assessments over range water-activity values time points obtain complete profile process. Conidia swelled, formed produced germlings just 0.585 (≡58.5% relative humidity), outside currently understood thermodynamic window life. Furthermore, analyses data suggest theoretical minimum 0.565 A. penicilliodes. In relation astrobiology, findings have an application limits extraterrestrial environments. light plans exploration missions Mars other places, need safeguard martian scientific sites potential resources (including water) future habitation, knowledge-based effective policy planetary protection essential. As it is, Mars-bound spacecraft may frequently be contaminated with aspergilli penicillioides) organisms which, when transported bodies, pose contamination risk. crafting countermeasures offset this, important know precisely possible capabilities interplanetary visitors.

Language: Английский

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Microbial lag phase can be indicative of, or independent from, cellular stress

Scientific Reports, Journal Year: 2020, Volume and Issue: 10(1)

Published: April 3, 2020

Abstract Measures of microbial growth, used as indicators cellular stress, are sometimes quantified at a single time-point. In reality, these measurements compound representations length lag, exponential growth-rate, and other factors. Here, we investigate whether lag phase can act proxy for using number model systems ( Aspergillus penicillioides ; Bacillus subtilis Escherichia coli Eurotium amstelodami , E. echinulatum halophilicum repens; Mrakia frigida Saccharomyces cerevisiae Xerochrysium xerophilum Xeromyces bisporus ) exposed to mechanistically distinct types stress including low water activity, solute-induced stresses, dehydration-rehydration cycles. Lag was neither proportional germination rate X. (FRR3443) in glycerol-supplemented media (r 2 = 0.012), nor growth-rates microbes. some cases, varied greatly with stressor concentration even when remained constant. By contrast, there were strong correlations B. supplemented polyethylene-glycol 6000 or 600 0.925 0.961), species. We also analysed data from independent studies food-spoilage fungi under glycerol aculeatinus A. sclerotiicarbonariu s); mesophilic/psychrotolerant bacteria diverse, stresses Brochothrix thermosphacta Enterococcus faecalis Pseudomonas fluorescens Salmonella typhimurium Staphylococcus aureus ); fungal enzymes acid-stress Terfezia claveryi lipoxygenase Agaricus tyrosinase). These datasets exhibited diversity, strong- moderate between growth-rates; none. conclusion, is not reliable measure because growth-rate inhibition highly correlated, all.

Language: Английский

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Antimicrobial activity of prodigiosin is attributable to plasma-membrane damage

Natural Product Research, Journal Year: 2016, Volume and Issue: 31(5), P. 572 - 577

Published: June 29, 2016

The bacterial pigment prodigiosin has various biological activities; it is, for instance, an effective antimicrobial. Here, we investigate the primary site targeted by prodigiosin, using cells of microbial pathogens humans as model systems: Candida albicans, Escherichia coli, Staphylococcus aureus. Inhibitory concentrations prodigiosin; leakage intracellular K+ ions, amino acids, proteins and sugars; impacts on activities proteases, catalases oxidases; changes in surface appearance pathogen were determined. Prodigiosin was highly inhibitory (30% growth rate reduction C. E. S. aureus at 0.3, 100 0.18 μg ml−1, respectively); caused substances (most severe aureus); to each enzyme; indicative cell-surface damage. Collectively, these findings suggest that log Poctanol–water 5.16, is not a toxin but hydrophobic stressor able disrupt plasma membrane via chaotropicity-mediated mode-of-action.

Language: Английский

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Advances in plant materials, food by-products, and algae conversion into biofuels: use of environmentally friendly technologies

Green Chemistry, Journal Year: 2019, Volume and Issue: 21(12), P. 3213 - 3231

Published: Jan. 1, 2019

Green technologies have emerged as useful tools for the generation of clean fuels with potential to minimize effect human activity on environment.

Language: Английский

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Water activity in Venus’s uninhabitable clouds and other planetary atmospheres

Nature Astronomy, Journal Year: 2021, Volume and Issue: 5(7), P. 665 - 675

Published: June 28, 2021

Language: Английский

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Advances in developing metabolically engineered microbial platforms to produce fourth-generation biofuels and high-value biochemicals

Bioresource Technology, Journal Year: 2021, Volume and Issue: 337, P. 125510 - 125510

Published: July 7, 2021

Language: Английский

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Microbial detoxification of lignocellulosic biomass hydrolysates: Biochemical and molecular aspects, challenges, exploits and future perspectives

Frontiers in Bioengineering and Biotechnology, Journal Year: 2022, Volume and Issue: 10

Published: Nov. 22, 2022

Valorization of lignocellulosic biomass (LB) has the potential to secure sustainable energy production without impacting food insecurity, whist relieving over reliance on finite fossil fuels. Agro-derived residues such as wheat straw, switchgrass, rice bran, and miscanthus have gained relevance feedstocks for biofuels chemicals. However, microorganisms employed in fermentative conversion carbohydrates fuels chemicals are unable efficiently utilize sugars derived from LB due co-production lignocellulose-derived microbial inhibitory compounds (LDMICs) during pretreatment. LDMICs impact growth by inhibition specific enzymes, cause DNA cell membrane damage, elicit cellular redox imbalance. Over past decade, success been achieved with removal prior fermentation. chemical processes is often accompanied sugar losses, which negatively impacts overall cost. Hence, situ organisms fermentation process garnered considerable attention "go-to" approach economical detoxification bio-chemicals production. In pursued either engineering more robust biocatalysts or isolating novel strains inherent capacity mineralize detoxify less toxic compounds. While some made along this line, efficient target hydrolysates (LHs) under largely anaerobic conditions remains a lingering challenge. Consequently, an underutilized substrate review, LH molecule discussed. Further, biochemical pathways mechanisms furanic [e.g., furfural 5-hydroxymethylfurfural (HMF)] phenolic (e.g., syringaldehyde, p-coumaric acid, 4-hydroxybenzaldehyde, vanillin, ferulic acid) More importantly, metabolic strategies development LDMIC-tolerant overproducing highlighted.

Language: Английский

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“Microbial life in salt caverns and their influence on H2 storage – Current knowledge and open questions.”

International Journal of Hydrogen Energy, Journal Year: 2024, Volume and Issue: 58, P. 1478 - 1485

Published: Feb. 3, 2024

Hydrogen will be one of the key components for renewable energy storage in future systems as it can stored significant volumes to overcome daily seasonal fluctuations. Subsurface salt caverns a first step. These are created by solution mining underground formations. Despite high salinity this environment, harbor microbial life. microorganisms not only survive these using unique adaptation mechanisms, but they actually cause several risks hydrogen storage. Different metabolisms use electron donor, leading loss and worst case also H2S formation. The knowledge on cavern microbiology subsequent possible effects is still its infancy limited number have been investigated so far. This review summarizes current questions about halophilic (salt-loving) microbes, their strategies, origin potential consequences metabolisms. It discusses major factors influencing activities risks. emphasizes that more research field trials with extensive monitoring needed before biologically active system safely achieved at global scale.

Language: Английский

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