Clostridia are obligate anaerobic bacteria that can produce solvents such as acetone, butanol and ethanol. Alcohol dehydrogenases (ADHs) play a key role in solvent production; however, their regulatory mechanisms remain largely unknown. In this study, we characterized the regulatory mechanisms of two ADH-encoding genes in C. beijerinckii. SigL (sigma factor σ ) was found to be required for transcription of adhA1 and adhA2 genes. Moreover, a novel transcriptional activator AdhR was identified, which binds to the σ promoter and activates σ -dependent transcription of adhA1 and adhA2. Clostridia beijerinckii mutants deficient in SigL or AdhR showed severely impaired butanol and ethanol production as well as altered acetone and butyrate synthesis. Overexpression of SigL resulted in significantly improved solvent production by C. beijerinckii when butyrate was added to cultures. Our results reveal SigL as a novel engineering target for improving solvent production by C. beijerinckii and other solvent-producing clostridia. Moreover, this study gains an insight into regulation of alcohol metabolism in diverse clostridia.
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http://dx.doi.org/10.1111/1751-7915.13505 | DOI Listing |
PLoS One
January 2025
Department of Applied Chemistry, National Defense Academy, Kanagawa, Japan.
Bacterial endospores are ubiquitous and are responsible for various human infections. Recently, we reported that an ionic liquid (IL)-based sample preparation method (named pTRUST) facilitated highly efficient shotgun analysis of the Bacillus subtilis spore proteome in trace samples. In this study, we evaluated the efficiency and applicability of the pTRUST technology using three different spore preparations: one purified from the closely related subspecies B.
View Article and Find Full Text PDFChemSusChem
January 2025
Dipartimento di Scienze Biologiche, Chimiche e Farmaceutiche, Università degli Studi di Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo, Italia.
Valorization of carbohydrate-rich biomass by conversion into industrially relevant products is at the forefront of research in sustainable chemistry. In this work, we studied the inulin conversion into 5-hydroxymethylfurfural, in deep eutectic solvents, in the presence of acidic task-specific ionic liquids as catalysts. We employed aliphatic and aromatic ionic liquids as catalysts, and choline chloride-based deep eutectic solvents bearing glycols or carboxylic acids, as solvents.
View Article and Find Full Text PDFChemSusChem
January 2025
Central South University, College of Chemistry and Chemical Engineering, No.932 South Lushan Road, Yuelu District, 410083, Changsha, CHINA.
The tightly connected structure of polybenzimidazole (PBI) membrane can be relaxed by solvent/nonsolvent solution to achieve a high proton conductivity for vanadium redox flow battery (VRFB). However, the nature behind the solvent/nonsolvent strategy is not unraveled. This work proposes a guideline to analyze the effect of PBI membrane relaxing formulas based on the interactions between different components in membranes.
View Article and Find Full Text PDFToxins (Basel)
December 2024
NMPA Key Laboratory for Quality Control of Traditional Chinese Medicine, Shanghai Institute for Food and Drug Control, 1500 Zhangheng Road, Shanghai 201203, China.
Puberulic acid (PA) is a mycotoxin produced by a species of . It has received widespread attention as a significant contributor to the reported fatalities associated with red yeast rice dietary supplements. However, the detection of PA, especially at low concentration levels, poses a considerable challenge, with no detection methods reported thus far.
View Article and Find Full Text PDFMar Drugs
January 2025
Institute of Nutrition and Food Technology 'José Mataix', Biomedical Research Center, University of Granada, 18071 Granada, Spain.
The optimization of bioactive compound extraction from using ultrasound-assisted extraction (UAE) via sonotrode was investigated to maximize phenolic recovery and antioxidant activity while promoting a sustainable process. Optimal conditions (40% / ethanol in water, 38 min, 36% amplitude) were selected to maximize phenolic recovery while considering environmental and energy sustainability by optimizing extraction efficiency and minimizing solvent and energy usage. HPLC-ESI-QTOF-MS analysis tentatively identified 25 phenolic compounds, including sulfated phenolic acids, phlorotannins, flavonoids, and halophenols, with some reported for the first time in , underscoring the complexity of this alga's metabolome.
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