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Methods in Molecular Biology (Clifton,... 2022Carbon dioxide (CO) has been increasingly regarded not only as a greenhouse gas but also as a valuable feedstock for carbon-based chemicals. In particular, biological...
Carbon dioxide (CO) has been increasingly regarded not only as a greenhouse gas but also as a valuable feedstock for carbon-based chemicals. In particular, biological approaches have drawn attention as models for the production of value-added products, as CO conversion serves many natural processes. Enzymatic CO reduction in vitro is a very promising route to produce fossil free and bio-based fuel alternatives, such as methanol. In this chapter, the advances in constructing competitive multi-enzymatic systems for the reduction of CO to methanol are discussed. Different integrated methods are presented, aiming to address technological challenges, such as the cost effectiveness, need for material regeneration and reuse and improving product yields of the process.
Topics: Carbon Dioxide; Methanol
PubMed: 35687244
DOI: 10.1007/978-1-0716-2269-8_19 -
Molecular Microbiology Dec 2022Methylotrophic yeasts can utilize methanol as the sole carbon and energy source, and the expression of their methanol-induced genes is regulated based on the...
Methylotrophic yeasts can utilize methanol as the sole carbon and energy source, and the expression of their methanol-induced genes is regulated based on the environmental methanol concentration. Our understanding of the function of transcription factors and Wsc family of proteins in methanol-induced gene expression and methanol sensing is expanding, but the methanol signal transduction mechanism remains undetermined. Our study has revealed that the transcription factor KpMxr1 is involved in the concentration-regulated methanol induction (CRMI) in Komagataella phaffii (Pichia pastoris) and that the phosphorylation state of KpMxr1 changes based on methanol concentration. We identified the functional regions of KpMxr1 and determined its multiple phosphorylation sites. Non-phosphorylatable substitution mutations of these newly identified phosphorylated threonine and serine residues resulted in significant defects in CRMI. We revealed that KpMxr1 receives the methanol signal from Wsc family proteins via KpPkc1 independent of the mitogen-activated protein kinase (MAPK) cascade and speculate that the activity of KpPkc1 influences KpMxr1 phosphorylation state. We propose that the CRMI pathway from Wsc to KpMxr1 diverges from KpPkc1 and that phosphoregulation of KpMxr1 plays a crucial role in CRMI.
Topics: Transcription Factors; Methanol; Pichia; Gene Expression Regulation, Fungal
PubMed: 36268798
DOI: 10.1111/mmi.14994 -
Angewandte Chemie (International Ed. in... Mar 2023Microbial cell factories provide a green and sustainable opportunity to produce value-added products from renewable feedstock. However, the leakage of toxic or volatile...
Microbial cell factories provide a green and sustainable opportunity to produce value-added products from renewable feedstock. However, the leakage of toxic or volatile intermediates decreases the efficiency of microbial cell factories. In this study, membraneless organelles (MLOs) were reconstructed in Saccharomyces cerevisiae by the disordered protein sequence A-IDPs. A regulation system was designed to spatiotemporally regulate the size and rigidity of MLOs. Manipulating the MLO size of strain ZP03-FM, the amounts of assimilated methanol and malate were increased by 162 % and 61 %, respectively. Furthermore, manipulating the MLO rigidity in strain ZP04-RB made acetyl-coA synthesis from oxidative glycolysis change to non-oxidative glycolysis; consequently, CO release decreased by 35 % and the n-butanol yield increased by 20 %. This artificial MLO provides a strategy for the co-localization of enzymes to channel C starting materials into value-added chemicals.
Topics: Saccharomyces cerevisiae; Biomolecular Condensates; Metabolic Engineering; Methanol; Oxidation-Reduction
PubMed: 36762978
DOI: 10.1002/anie.202215778 -
Food Chemistry Dec 2023In situ and on-site analysis of trace components, such as methanol and ethyl acetate, in distilled spirits poses significant challenges. In this study, we have proposed...
In situ and on-site analysis of trace components, such as methanol and ethyl acetate, in distilled spirits poses significant challenges. In this study, we have proposed a simple, yet effective and rapid approach that combines Raman spectroscopy with Raman integrating sphere technology to accurately detect trace constituents in distilled spirits. An external standard method to effectively separate overlapping Raman peaks from different substances are developed. Experimental results demonstrate that with an exposure time of 180 s under normal temperature and pressure, the detection limits for methanol, acetic acid, and ethyl acetate in proportioned distilled spirits are below 0.1 g/L. Importantly, the detection limit of methanol and acetic acid remains unaffected by the concentration of distilled spirits and the types of trace substances. Notably, the concentration of trace solute exhibits a highly linear relationship with its corresponding Raman intensity, offering a reliable probe for identifying unknown components in distilled spirits.
Topics: Methanol; Alcoholic Beverages; Spectrum Analysis, Raman; Acetic Acid
PubMed: 37478606
DOI: 10.1016/j.foodchem.2023.136851 -
Food Chemistry Jan 2023A multi-channel colorimetric device was developed for the low-cost and simultaneous determination of three important parameters in wine safety and quality- total iron...
A multi-channel colorimetric device was developed for the low-cost and simultaneous determination of three important parameters in wine safety and quality- total iron (Fe), methanol (MeOH), and total phenols. The detection was performed by assembling light-dependent resistors and light-emitting diodes in a 3D printed chamber, which measured colorimetric signals horizontally transmitting through the microwells of an 8-well strip. This device demonstrated linear relationships (R greater than 0.99) for all analytes with detection limits of 0.04 mg/L, 2.26 mg/L, and 3.40 mg/L for Fe, MeOH, and total phenols, respectively. Wine sample measurements showed that the multi-channel device was as accurate as the professional spectrophotometer and could simultaneously provide the three target concentrations to facilitate the analysis. With the merits of low fabrication cost and ease of use, this device could be used as a general platform for multiple-target detection, demonstrating great potential for application in food analysis.
Topics: Colorimetry; Food Analysis; Methanol; Phenols; Wine
PubMed: 35973298
DOI: 10.1016/j.foodchem.2022.133907 -
Astrobiology May 2020Numerous laboratory studies of astrophysical ice analogues have shown that their exposure to ionizing radiation leads to the production of large numbers of new, more...
Numerous laboratory studies of astrophysical ice analogues have shown that their exposure to ionizing radiation leads to the production of large numbers of new, more complex compounds, many of which are of astrobiological interest. We show here that the irradiation of astrophysical ice analogues containing HO, CHOH, CO, and NH yields quantities of hexamethylenetetramine-methanol (hereafter HMT-methanol; CNHO) that are easily detectible in the resulting organic residues. This molecule differs from simple HMT, which is known to be abundant in similar ice photolysis residues, by the replacement of a peripheral H atom with a CHOH group. As with HMT, HMT-methanol is likely to be an amino acid precursor. HMT has tetrahedral () symmetry, whereas HMT-methanol has symmetry. We report the computed expected infrared spectra for HMT and HMT-methanol obtained using quantum chemistry methods and show that there is a good match between the observed and computed spectra for regular HMT. Since HMT-methanol lacks the high symmetry of HMT, it produces rotational transitions that could be observed at longer wavelengths, although establishing the exact positions of these transitions may be challenging. It is likely that HMT-methanol represents an abundant member of a larger family of functionalized HMT molecules that may be present in cold astrophysical environments.
Topics: Exobiology; Extraterrestrial Environment; Methanol; Methenamine; Vibration
PubMed: 32105506
DOI: 10.1089/ast.2019.2147 -
Trends in Biotechnology Apr 2021The toxic C1 compounds methanol and formaldehyde are generated during bioconversion of lignin into value-added chemicals. These toxins can be detoxified and assimilated...
The toxic C1 compounds methanol and formaldehyde are generated during bioconversion of lignin into value-added chemicals. These toxins can be detoxified and assimilated by methylotrophs to synthesize useful metabolites and cell biomass. We discuss the promising future of constructing integrated biosystems to use toxic C1 byproducts and promote lignin valorization.
Topics: Biomass; Formaldehyde; Lignin; Methanol
PubMed: 33008644
DOI: 10.1016/j.tibtech.2020.09.005 -
ACS Applied Materials & Interfaces Jan 2020Using enzymes as bioelectrocatalysts is an important step toward the next level of biotechnology for energy production. In such biocatalysts, a sacrificial cofactor as...
Using enzymes as bioelectrocatalysts is an important step toward the next level of biotechnology for energy production. In such biocatalysts, a sacrificial cofactor as an electron and proton source is needed. This is a great obstacle for upscaling, due to cofactor instability and product separation issues, which increase the costs. Here, we report a cofactor-free electroreduction of CO to a high energy density chemical (methanol) catalyzed by enzyme-graphene hybrids. The biocatalyst consists of dehydrogenases covalently bound on a well-defined carboxyl graphene derivative, serving the role of a conductive nanoplatform. This nanobiocatalyst achieves reduction of CO to methanol at high current densities, which remain unchanged for at least 20 h of operation, without production of other soluble byproducts. It is thus shown that critical improvements on the stability and rate of methanol production at a high Faradaic efficiency of 12% are possible, due to the effective electrochemical process from the electrode to the enzymes via the graphene platform.
Topics: Biocatalysis; Carbon Dioxide; Enzymes, Immobilized; Graphite; Methanol; Oxidation-Reduction
PubMed: 31816230
DOI: 10.1021/acsami.9b17777 -
Mycotoxin Research Aug 2023The antifungal and antiaflatoxigenic effects of four distinct plant species against Aspergillus flavus and Aspergillus parasiticus were investigated. Essential oils and...
The antifungal and antiaflatoxigenic effects of four distinct plant species against Aspergillus flavus and Aspergillus parasiticus were investigated. Essential oils and methanolic extracts were prepared from aerial parts of Lippia javanica, Ocimum gratissimum, Satureja punctata, and stem barks of Toddalia asiatica by hydro-distillation and maceration, respectively. The poisoned food method was used to confirm the antifungal activity of essential oils and methanolic extracts from four different plant species against Aspergillus flavus and Aspergillus parasiticus, and high-performance liquid chromatography was used to quantify the antiaflatoxigenic activity. The essential oils of Satureja punctata and Lippia javanica showed the highest antiaflatoxigenic activity against the fungi strains tested at concentrations of 1.25, 2.5, and 5 µL/mL, followed by Ocimum gratissimum essential oil while Toddalia asiatica essential oil exerted moderate antiaflatoxigenic activity. Meanwhile, the methanolic extracts showed a wide spectrum of low to high antifungal and antiaflatoxigenic activities at concentrations of 125, 250, and 500 µg/mL against A. flavus and A. parasiticus. This study has indicated that the essential oils of Satureja punctate, Lippia javanica, and Ocimum gratissimum had substantial antifungal and antiaflatoxigenic activities compared to their methanolic extracts, while Toddalia asiatica methanolic extract had a moderate antifungal activity compared to its essential oil.
Topics: Aspergillus flavus; Oils, Volatile; Aflatoxins; Antifungal Agents; Methanol; Plant Extracts
PubMed: 37261704
DOI: 10.1007/s12550-023-00490-6 -
Molecules (Basel, Switzerland) Dec 2019Methanol is metabolized in the body to highly toxic formaldehyde and formate when consumed accidentally. Methanol has been typically analyzed with gas...
Methanol is metabolized in the body to highly toxic formaldehyde and formate when consumed accidentally. Methanol has been typically analyzed with gas chromatography-flame ionization detector (GC-FID). However, its retention time may overlap with other volatile compounds and lead to confusion. Alternative analysis of methanol using gas chromatography/mass spectrometry (GC/MS) also has limitations due to its similar molecular weight with oxygen and low boiling point. In this study, methanol and internal standard of deuterium-substituted ethanol were derivatized with 3,4-dihydro-2H-pyran under acid catalysis using concentrated hydrochloric acid. The reaction products including 2-methoxytetrahydropyran were extracted with solid-phase microextraction followed by GC/MS analysis. This method was successfully applied to measure the lethal concentration of methanol in the blood of a victim with a standard addition method to overcome the complex matrix effect of the biospecimen. Identification of the metabolite formate by ion chromatography confirmed the death cause to be methanol poisoning. This new method was a much more convenient and reliable process to measure methanol in complex matrix samples by reducing sample pretreatment effort and cost.
Topics: Benzenesulfonates; Gas Chromatography-Mass Spectrometry; Humans; Methanol; Pyrans
PubMed: 31877660
DOI: 10.3390/molecules25010041