Elucidating the Biosynthesis and Function of an Autoinducing Peptide in Clostridium acetobutylicum.

Clostridia produce autoinducing peptides (AIPs) regulated by the accessory gene regulator (Agr) quorum sensing system, playing a critical role in intercellular communication. However, the biosynthetic pathway and regulatory functions of clostridial AIPs remain inadequately characterized. In this study, we employed chemical quantification, genetic investigations, and in vitro reconstitution experiments to elucidate the native Ca-AIP in Clostridium acetobutylicum, a prominent industrial producer of acetone, butanol, and ethanol.

Lignocellulosic ethanol and butanol production by Saccharomyces cerevisiae and Clostridium beijerinckii co-culture using non-detoxified corn stover hydrolysate.

Considering global economic and environmental -benefits, green renewable biofuels such as ethanol and butanol are considered as sustainable alternatives to fossil fuels. Thus, developing a co-culture strategy for ethanol and butanol production by Saccharomyces cerevisiae and Clostridium beijerinckii has emerged as a promising approach for biofuel production from lignocellulosic biomass. This study developed a co-culture of S.

Identification of serine/threonine kinases that regulate metabolism and sporulation in Clostridium beijerinckii.

Serine/threonine protein kinases (STKs) are important for signal transduction and involved in multiple physiological processes, including cell growth, central metabolism, and sporulation in bacteria. However, the role of STKs in solventogenic clostridia remains unclear. Here, we identified and comprehensively investigated six STK candidates in Clostridium beijerinckii.

Effects of orphan histidine kinases on clostridial sporulation progression and metabolism.

Solventogenesis and sporulation of clostridia are the main responsive adaptations to the acidic environment during acetone-butanol-ethanol (ABE) fermentation. It was hypothesized that five orphan histidine kinases (HKs) including Cac3319, Cac0323, Cac0903, Cac2730, and Cac0437 determined the cell fates between sporulation and solventogenesis. In this study, the comparative genomic analysis revealed that a mutation in cac0437 appeared to contribute to the nonsporulating feature of ATCC 55025.

Pleiotropic regulation of a glucose-specific PTS in for high-efficient butanol production from corn stover without detoxification.

Background: Corn stover (CS) is evaluated as the most favorable candidate feedstock for butanol production via microbial acetone-butanol-ethanol (ABE) fermentation by . By independent acid pretreatment and enzymatic hydrolysis, fermentable sugars (mainly glucose and xylose) were released, of which glucose was naturally utilized as the most preferred carbon source by . However, the ABE fermentation using corn stover hydrolysate (CSH) without detoxification is typically limited to poor sugars utilization, butanol production and productivity.

Hybrid dilute sulfuric acid and aqueous ammonia pretreatment for improving butanol production from corn stover with reduced wastewater generation.

An efficient hybrid pretreatment method was developed for butanol production from corn stover using dilute sulfuric acid (DA) and aqueous ammonia (AA). With the optimized AA concentration, treatment temperature and time of 10% AA, 80 °C and 24 h, the hybrid pretreatment could effectively dissolve hemicellulose and lignin with solid recovery rate of 37.45% and lignin reduction rate of 86.

Improving Fructose Utilization and Butanol Production by Clostridium acetobutylicum via Extracellular Redox Potential Regulation and Intracellular Metabolite Analysis.

Jerusalem artichoke (JA) can grow well in marginal lands with high biomass yield, and thus is a potential energy crop for biorefinery. The major biomass of JA is from tubers, which contain inulin that can be easily hydrolyzed into a mixture of fructose and glucose, but fructose utilization for producing butanol as an advanced biofuel is poor compared to glucose-based ABE fermentation by Clostridium acetobutylicum. In this article, the impact of extracellular redox potential (ORP) on the process is studied using a mixture of fructose and glucose to simulate the hydrolysate of JA tubers.

Synergistic effect of calcium and zinc on glucose/xylose utilization and butanol tolerance of Clostridium acetobutylicum.

Biobutanol outperforms bioethanol as an advanced biofuel, but is not economically competitive in terms of its titer, yield and productivity associated with feedstocks and energy cost. In this work, the synergistic effect of calcium and zinc was investigated in the acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum using glucose, xylose and glucose/xylose mixtures as carbon source(s). Significant improvements associated with enhanced glucose/xylose utilization, cell growth, acids re-assimilation and butanol biosynthesis were achieved.

Impact of zinc supplementation on the improved fructose/xylose utilization and butanol production during acetone-butanol-ethanol fermentation.

Lignocellulosic biomass and dedicated energy crops such as Jerusalem artichoke are promising alternatives for biobutanol production by solventogenic clostridia. However, fermentable sugars such as fructose or xylose released from the hydrolysis of these feedstocks were subjected to the incomplete utilization by the strains, leading to relatively low butanol production and productivity. When 0.

Effect of zinc supplementation on acetone-butanol-ethanol fermentation by Clostridium acetobutylicum.

In this article, effect of zinc supplementation on acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum was studied. It was found that when 0.001 g/L ZnSO4·7H2O was supplemented into the medium, solventogenesis was initiated earlier, with 21.

[Screening of Clostridium strains through ribosome engineering for improved butanol production].

We used ribosome engineering technology, with which antibiotic-resistant strains are resulted from mutations on microbial ribosome, to screen a high butanol-producing Clostridium strain. A novel mutant strain S3 with high butanol production and tolerance was obtained from the original Clostridium acetobutylicum L7 with the presence of mutagen of streptomycin. Butanol of 12.