Novel insights into the biological state in algal-bacterial granular sludge granulation: Armor-like protection provided by the algal barrier.

Algal-bacterial granular sludge (ABGS) composed of microalgae and aerobic granular sludge, is a sustainable and promising technology for wastewater treatment. However, the formation mechanism of ABGS has not been clearly defined, and the direct formation of ABGS in saline wastewater has rarely been investigated. This study proposed novel insights into the granulation process of ABGS by assembling the algal barrier, which was successfully cultivated directly in saline wastewater.

Revealing the Mechanisms of Enhanced β-Farnesene Production in through Metabolomics Analysis.

β-Farnesene is an advanced molecule with promising applications in agriculture, the cosmetics industry, pharmaceuticals, and bioenergy. To supplement the shortcomings of rational design in the development of high-producing β-farnesene strains, a Metabolic Pathway Design-Fermentation Test-Metabolomic Analysis-Target Mining experimental cycle was designed. In this study, by over-adding 20 different amino acids/nucleobases to induce fluctuations in the production of β-farnesene, the changes in intracellular metabolites in the β-farnesene titer-increased group were analyzed using non-targeted metabolomics.

Metabolic Engineering for Effective Synthesis of 2-Hydroxyadipate.

Adipic acid is an important monomer in the synthesis of nylon-6,6. In recent years, the biosynthesis of adipic acid has received more and more attention. The pathway with l-lysine as a precursor has potential for adipic acid synthesis, and 2-hydroxyadipate is a key intermediate metabolite in this pathway.

A Highly Sensitive Model Based on Graph Neural Networks for Enzyme Key Catalytic Residue Prediction.

Determining the catalytic site of enzymes is a great help for understanding the relationship between protein sequence, structure, and function, which provides the basis and targets for designing, modifying, and enhancing enzyme activity. The unique local spatial configuration bound to the substrate at the active center of the enzyme determines the catalytic ability of enzymes and plays an important role in the catalytic site prediction. As a suitable tool, the graph neural network can better understand and identify the residue sites with unique local spatial configurations due to its remarkable ability to characterize the three-dimensional structural features of proteins.

Synergistic analysis of performance, microbial community, and metabolism in aerobic granular sludge under polyacrylonitrile microplastics stress.

Aerobic granular sludge (AGS) has proved to be a promising biotechnology for microplastics wastewater treatment. However, polyacrylonitrile microplastics (PAN MPs), the most widely used plastic in textile materials, have not been investigated. Therefore, the effect of the neglected PAN MPs on AGS at different concentrations (1, 10, and 100 mg/L) was evaluated.

Enhancing precursor supply and modulating metabolism to achieve high-level production of β-farnesene in Yarrowia lipolytica.

β-Farnesene is a sesquiterpene commonly found in essential oils of plants, with applications spanning from agricultural pest control and biofuels to industrial chemicals. The use of renewable substrates in microbial cell factories offers a sustainable approach to β-farnesene biosynthesis. In this study, malic enzyme from Mucor circinelloides was examined for NADPH regeneration, concomitant with the augmentation of cytosolic acetyl-CoA supply by expressing ATP-citrate lyase from Mus musculus and manipulating the citrate pathway via AMP deaminase and isocitrate dehydrogenase.

De novo biosynthesis of α-aminoadipate via multi-strategy metabolic engineering in Escherichia coli.

As a non-protein amino acid, α-aminoadipate is used in the fields of medicine, chemical engineering, food science, and others. For example, α-aminoadipate is an important precursor for the production of β-lactam antibiotics. Currently, the synthesis of α-aminoadipate depends on chemical catalysis that has the disadvantages of high cost, low yield, and serious pollution.

Prediction of Plasticizer Property Based on an Improved Genetic Algorithm.

Different plasticizers have obvious differences in plasticizing properties. As one of the important indicators for evaluating plasticization performance, the substitution factor (SF) has great significance for product cost accounting. In this research, a genetic algorithm with "variable mutation probability" was developed to screen the key molecular descriptors of plasticizers that are highly correlated with the SF, and a SF prediction model was established based on these filtered molecular descriptors.

Improved energy efficiency in microbial fuel cells by bioethanol and electricity co-generation.

Background: Microbial electricity production has received considerable attention from researchers due to its environmental friendliness and low price. The increase in the number of intracellular electrons in a microbial fuel cell (MFC) helps to improve the MFC performance.

Results: In this study, we accumulated excess electrons intracellularly by knocking out the gene related to intracellular electron consumption in Saccharomyces cerevisiae, and the elevated intracellular electron pool positively influenced the performances of MFCs in terms of electricity production, while helping to increase ethanol production and achieve ethanol and electricity co-production, which in turn improved the utilization of substrates.

Cross-linking of carbonic anhydrase and formate dehydrogenase based on amino acid specific recognition: Conversion of carbon dioxide to formic acid.

Inspired by the cascades performed in vivo, the assembly of multiple enzymes in vitro has strongly moved into the focus of researchers in the field of biocatalysis. In this study, a new, mild and accurate enzyme cross-linking method is revealed. Microbial transglutaminase (MTG) acts as a "cross-linking medium" by identifying the amide group of the glutamine and the primary amine group of lysine in the artificial peptide tags specifically to form an iso-peptide bond.

Quantification of alcohols, diols and glycerol in fermentation with an instantaneous derivatization using trichloroacetyl isocyanante via liquid chromatography-massspectrometry.

A sensitive LC-MS/MS method was established to quantify diols and glycerol in fermentation broth using trichloroacetyl isocyanate as instantaneous derivatization reagent for monitoring the production of 1,3-propanediol and 2,3-butanediol from the biodiesel biorefinery process. Due to the derivatization reaction was very quickly at room temperature, only 1 min was needed for the reaction process. In addition, both extraction of analytes and evaporation of water were not employed in the analytical procedure.

Simultaneous acetone-butanol-ethanol fermentation, gas stripping, and full-cell-catalyzed esterification for effective production of butyl oleate.

In this study, aiming to improve the economic feasibility of acetone-butanol-ethanol (ABE) fermentation process, generate valuable products and extend the product chain, esterification catalyzed by Candida sp. 99-125 cells was hybrid with the ABE fermentation-gas-stripping integration system. The gas-stripping condensate that contained concentrated ABE products was directly used for esterification without the participation of toxic organic solvents.

Bio-plasticizer production by hybrid acetone-butanol-ethanol fermentation with full cell catalysis of Candida sp. 99-125.

Hybrid process that integrated fermentation, pervaporation and esterification was established aiming to improve the economic feasibility of the conventional acetone-butanol-ethanol (ABE) fermentation process. Candida sp 99-125 cells were used as full-cell catalyst. The feasibility of batch and fed-batch esterification using the ABE permeate of pervaporation (ranging from 286.

Cofactor engineering for more efficient production of chemicals and biofuels.

Cofactors are involved in numerous intracellular reactions and critically influence redox balance and cellular metabolism. Cofactor engineering can support and promote the biocatalysis process, even help driving thermodynamically unfavorable reactions forwards. To achieve efficient production of chemicals and biofuels, cofactor engineering strategies such as altering cofactor supply or modifying reactants' cofactor preference have been developed to maintain redox balance.

Environmentally-friendly strategy for separation of 1,3-propanediol using biocatalytic conversion.

Glycerol waste from the biodiesel production can be used as a carbon source in the production of 1,3-propanediol (1,3-PD) through microbial fermentation. However, downstream processing is a major bottleneck that restricts its biological production. Here, we investigated an environmentally-friendly method to enzymatically separate 1,3-PD.

Enzymatic phosphorylation of mannose by glucomannokinase from Mycobacterium phlei using inorganic polyphosphate.

Mannose-6-phosphate is an important phosphor-sugar, which is involved in many physiological functions and it is used to treat many diseases. Its production is however expensive since it requires costly substrate ATP as phosphorylation agent. This study has focused upon the direct synthesis of M6P by glucomannokinase using inorganic polyphosphate without involvement of ATP.

Genipin Cross-Linked Glucose Oxidase and Catalase Multi-enzyme for Gluconic Acid Synthesis.

In this work, glucose oxidase (GOD) and catalase (CAT) were used simultaneously to produce gluconic acid from glucose. In order to reduce the distance between the two enzymes, and therefore improve efficiency, GOD and CAT were cross-linked together using genipin. Improvements in gluconic acid production were due to quick removal of harmful intermediate hydrogen peroxide by CAT.

Immobilization of Yarrowia lipolytica lipase Ylip2 for the biocatalytic synthesis of phytosterol ester in a water activity controlled reactor.

In this work, phytosterol ester was synthesized using Yarrowia lipolytica lipase Ylip2 that had been immobilized on inorganic support in a solvent-free system and reacted in a computer-aided water activity controlled bioreactor. The immobilization of Ylip2 on celite led to a remarkable increase in the phytosterol conversion compared to that of free lipase. An investigation of the reaction conditions were oleic acid as the fatty acid variety, 10,000U/g substrate, and a temperature of 50°C for phytosterol ester synthesis.

Immobilizing Yarrowia lipolytica Lipase Lip2 via Improvement of Microspheres by Gelatin Modification.

The purpose of this study was to investigate the feasibility of immobilizing Yarrowia lipolytica lipase lip2 on epoxy microspheres with or without gelatin modifications. The activity of lipase immobilized on gelatin-modified supports was twofold higher than those immobilized on native supports. There was no significant difference in the Michaelis-Menten constant (K M ) between the two immobilized lipases.

Synergistic effects of amine and protein modified epoxy-support on immobilized lipase activity.

We have developed an improved and effective method to immobilize Yarrowia lipolytica lipase Lip2 (YLIP2) on an epoxy poly-(glycidylmethacrylate-triallyisocyanurate-ethyleneglycoldimethacrylate) (PGMA-TAIC-EGDMA) support structure with or without amine or/and protein modifications. Our results show that there is an increase in the activity of the immobilized lipase on n-butylamine (BA) modified support (420U/g support) and the biocompatible gelatin modified support (600U/g support) when compared to the support without modification (240U/g support). To further study the influences of BA and gelatin modification on the activity of the immobilized lipase, gelatin and BA were concurrently used to decorate the support structure.

Solvothermal synthesis of functional magnetic nanoparticles for biocatalyst.

A facile and simple one-step solvothermal method has been developed to synthesize polyethyleneimine (PEI)-modified magnetic nanoparticles. Characterization of morphology, surface charges, crystal structure, and magnetic property confirmed the efficiency of this facile synthesis route. Lipase immobilized on the PEI-modified magnetic nanoparticles was used to synthesize vitamin A palmitate from vitamin A acetate and palmitic acid.

Enhancing trimethylolpropane esters synthesis through lipase immobilized on surface hydrophobic modified support and appropriate substrate feeding methods.

Candida sp. 99-125 lipase immobilized on surface hydrophobic modified support and appropriate substrate feeding methods were used to improve the synthesis of tri-substituted trimethylolpropane (TMP) esters, which can be used as raw materials for biodegradable lubricants. The proposed novel production method is environmentally friendly.

Theoretical and experimental studies on activity of Yarrowia lipolytica lipase in methanol/water mixtures.

Methanol is regularly used as a substrate for biodiesel synthesis. Excess methanol can however inhibit the lipase activity. In the present work, the activity and conformational changes of Yarrowia lipolytica lipase (LIP2) at different concentrations of methanol were investigated by measuring fluorescence, UV-vis spectra, and molecular dynamics simulations.

Lipase-catalyzed synthesis and characterization of polymers by cyclodextrin as support architecture.

Diesters and diols were successfully converted into aliphatic polyesters by enzymatic lipase Candida sp.99-125 catalysis, with β-cyclodextrin acting as supporting architecture (in a similar way as chaperone proteins). No organic solvents were used.

Enzymatic synthesizing of phytosterol oleic esters.

A method of synthesizing the phytosterol esters from oleic acid and sterols was studied, using immobilized lipase Candida sp. 99-125 as catalyst. Molar ratio (oleic acid/phytosterols), temperature, reaction period, organic solvents, catalyst, and silica-gel drier were optimized, and the result showed that 93.