Protein Engineering of Substrate Specificity toward Nitrilases: Strategies and Challenges.

Nitrilase is extensively applied across diverse sectors owing to its unique catalytic properties. Nevertheless, in industrial production, nitrilases often face issues such as low catalytic efficiency, limited substrate range, suboptimal selectivity, and side reaction products, which have garnered heightened attention. With the widespread recognition that the structure of enzymes has a direct impact on their catalytic properties, an increasing number of researchers are beginning to optimize the functional characteristics of nitrilases by modifying their structures, in order to meet specific industrial or biotechnology application needs.

Yeast community in the first-round fermentation of sauce-flavor Baijiu: Source, succession and metabolic function.

Yeasts play a crucial role in determining the quality and yield of sauce-flavor Baijiu, yet the source, succession, and metabolic functions of the yeast community in fermented grains during stacking fermentation remains unclear. In this study, amplicon sequencing combined with solid-state fermentation was used to investigate the structure and function of yeast community during the first-round fermentation of sauce-flavor Baijiu. The richness and diversity of yeast community increased throughout fermentation, with 83.

Regulatory significance of terminator: A systematic approach for dissecting terminator-mediated enhancement of upstream mRNA stability.

The primary function of terminators is to terminate transcription in gene expression. Although some studies have suggested that terminators also contribute positively to upstream gene expression, the extent and underlying mechanism of this effect remain largely unexplored. Here, the correlation between terminating strength and upstream mRNA stability was investigated by constructing a terminator mutation library through randomizing 5 nucleotides, assisted by FlowSeq technology, terminator variants were categorized based on the downstream fluorescence intensity, followed by high-throughput sequencing.

Identification of a bacteria P450 enzyme from B. megaterium H-1 with vitamin D C-25 hydroxylation capabilities.

Calcidiol (25(OH)VD) and calcitriol (1α,25(OH)VD) are active vitamin D with high medicinal value, which can maintain calcium and phosphorus balance and treat vitamin D deficiency. Microbial synthesis is an important method to produce high-value-added compounds. It can produce active vitamin D through the hydroxylation reaction of P450, which can reduce the traditional chemical synthesis steps, and greatly improve the production efficiency and economic benefits.

A comprehensive review on microbial hyaluronan-degrading enzymes: from virulence factors to biotechnological tools.

Hyaluronan (HA), a natural high molecular weight polysaccharide, has extensive applications in cosmetology and medical treatment. Hyaluronan-degrading enzymes (Hyals) act as molecular scissors that cleave HA by breaking the glucosidic linkage. Hyals are present in diverse organisms, including vertebrates, invertebrates and microorganisms, and play momentous roles in biological processes.

Unlocking Green Biomanufacturing Potential: Superior Heterologous Gene Expression with a T7 Integration Overexpression System in .

Industrial biotechnology employs cells for producing valuable products and serving as biocatalysts sustainably, addressing resource, energy, and environmental issues. is a preferred host for creating microbial chassis cells and producing industrial enzymes and functional nutritional products. In this study, a dual-module T7 integration expression system in was established.

The efficient green bio-manufacturing of Vitamin K: design, production and applications.

Vitamin K, also known as methylnaphthoquinone, is a crucial fat-soluble nutrient necessary for the human body. The biological production of Vitamin K has received widespread attention due to its environmental friendliness and maneuverability in recent years. This review provides insights into the modular metabolic pathways of Vitamin K, lays the foundation for microbial metabolic flow balancing, cofactor engineering and dynamic regulation, and realizes the production of Vitamin K by synthesizing artificial cells from scratch.

Protein Engineering of Nicotinamide Riboside Kinase Based on a Combinatorial Semirational Design Strategy for Efficient Biocatalytic Synthesis of Nicotinamide Mononucleotides.

Industrial biosynthesis of β-nicotinamide mononucleotide (β-NMN) lacks a highly active nicotinamide riboside kinase for the phosphorylation process. Cumbersome preprocessing steps and excessive ATP addition contribute to its increased cost. To tackle these challenges, a docking combination simulation (DCS) semirational mutagenesis strategy was designed in this study, combining various modification strategies to obtain a mutant NRK-TRA with 2.

Identification and Characterization of a Highly Active Hyaluronan Lyase from .

Hyaluronic acid (HA) is a well-known functional marine polysaccharide. The utilization and derivative development of HA are of great interest. Hyaluronan lyase has wide application prospects in the production of HA oligosaccharides and lower molecular weight HA.

Multilevel Systematic Optimization To Achieve Efficient Integrated Expression of .

Genomic integration of heterologous genes is the preferred approach in industrial fermentation-related strains due to the drawbacks associated with plasmid-mediated microbial fermentation, including additional growth burden, genetic instability, and antibiotic contamination. Synthetic biology and genome editing advancements have made gene integration convenient. Integrated expression is extensively used in the field of biomanufacturing and is anticipated to become the prevailing method for expressing recombinant proteins.

In situ encapsulation of capsaicinoids in MIL-88A as a food-grade nanopreservative for meat safety.

The biocompatible MIL-88A metal-organic framework (MOF), synthesized from food-grade fumaric acid and ferric chloride, was introduced for the efficient one-step in situ encapsulation of capsaicinoids as a nanopreservative. The resulting MIL-88A@Caps nanoparticles can load 61.43 mg/g of capsaicinoids, surpassing conventional MOF-based encapsulation.

Unraveling the intricacies of glycosaminoglycan biosynthesis: Decoding the molecular symphony in understanding complex polysaccharide assembly.

Glycosaminoglycans (GAGs) are extensively utilized in clinical, cosmetic, and healthcare field, as well as in the treatment of thrombosis, osteoarthritis, rheumatism, and cancer. The biological production of GAGs is a strategy that has garnered significant attention due to its numerous advantages over traditional preparation methods. In this review, we embark on a journey to decode the intricate molecular symphony that orchestrates the biosynthesis of glycosaminoglycans.

Restricted intake of sulfur-containing amino acids reversed the hepatic injury induced by excess through gut-liver axis.

Diet is a key player in gut-liver axis. However, the effect of different dietary patterns on gut microbiota and liver functions remains unclear. Here, we used rodent standard chow and purified diet to mimic two common human dietary patterns: grain and plant-based diet and refined-food-based diet, respectively and explored their impacts on gut microbiota and liver.

Decoding the Qu-aroma of medium-temperature Daqu starter by volatilomics, aroma recombination, omission studies and sensory analysis.

Qu-aroma is of great significance for evaluation the quality of Daqu starter. This study aimed to decode the Qu-aroma of medium-temperature Daqu (MT-Daqu) via "top-down" and "bottom-up" approaches. Firstly, 52 aroma descriptors were defined to describe the MT-Daqu aroma by quantitative descriptive analysis.

Food-derived peptides unleashed: emerging roles as food additives beyond bioactivities.

Innovating food additives stands as a cornerstone for the sustainable evolution of future food systems. Peptides derived from food proteins exhibit a rich array of physicochemical and biological attributes crucial for preserving the appearance, flavor, texture, and nutritional integrity of foods. Leveraging these peptides as raw materials holds great promise for the development of novel food additives.

A Free Amino Acid Diet Alleviates Colorectal Tumorigenesis through Modulating Gut Microbiota and Metabolites.

Colorectal cancer (CRC), a major global health concern, may be influenced by dietary protein digestibility impacting gut microbiota and metabolites, which is crucial for cancer therapy effectiveness. This study explored the effects of a casein protein diet (CTL) versus a free amino acid (FAA)-based diet on CRC progression, gut microbiota, and metabolites using carcinogen-induced (AOM/DSS) and spontaneous genetically induced ( mice) CRC mouse models. Comprehensive approaches including 16s rRNA gene sequencing, transcriptomics, metabolomics, and immunohistochemistry were utilized.

[Metagenomics unveils the differences in the functions of microbial community of medium-temperature Daqu before and after maturation].

Daqu is the saccharifying, fermenting, and aroma-producing agent used in Baijiu brewing, and its maturation is crucial for obtaining high-quality Daqu. Previous studies have explored the microbial community composition and diversity before and after maturation. However, little is known about the changes in the functions of microbial community.

Enhanced synthesis of S-adenosyl-L-methionine through combinatorial metabolic engineering and Bayesian optimization in Saccharomyces cerevisiae.

S-Adenosyl-L-methionine (SAM) is a substrate for many enzyme-catalyzed reactions and provides methyl groups in numerous biological methylations, and thus has vast applications in the agriculture and medical field. Saccharomyces cerevisiae has been engineered as a platform with significant potential for producing SAM, but the current production has room for improvement. Thus, a method that consists of a series of metabolic engineering strategies was established in this study.

Enhanced Production of Sisomicin in Micromonospora inyoensis by Protoplast Mutagenesis and Fermentation Optimization.

Sisomicin is a broad-spectrum aminoglycoside antibiotic and is the precursor of netilmicin and plazomicin. However, the fermentation level of sisomicin is still low compared with other antibiotics, which restricts the application of sisomicin and its derivatives. In this study, to improve sisomicin production, breeding of high-yielding sisomicin strains was conducted with chemical mutagenesis using Micromonospora inyoensis OG-1 (titer, 1042 U·mL) as the starting strain.