Bioscience, Biotechnology, and Biochemistry最新文献

A streamlined synthesis of sialylgalactose (NeuGal) analogs is described. Neuα(2,6)Gal and Neuα(2,3)Gal units were synthesized via fully α-selective sialylation of suitable Gal acceptors using a bicyclic sialyl donor. NeuGals were diversified through C5 amino group modification and sulfation, yielding NeuGal analogs with an amino linker for biological studies.

Lignocellulosic biomass is a carbon-neutral resource crucial to advancing a bio-based economy. The filamentous fungus Talaromyces cellulolyticus demonstrates superior biomass saccharification efficiency compared to conventional enzyme-producing fungi, making it a promising host for enzymatic biomass conversion. To enable molecular studies, we developed a robust genetic transformation system for T. cellulolyticus and identified key transcription factors regulating saccharifying enzyme genes, classified into 3 functional groups. Manipulation of these regulators significantly enhanced enzyme production. Additionally, we purified individual enzymes and conducted biochemical and structural analyses, leading to the discovery of a novel xylanase with unique side-chain recognition. The integration of genetic and enzymatic insights advances both our understanding of fungal saccharification systems and the development of more efficient biomass-to-sugar conversion strategies for sustainable biotechnological applications.

Renal fibrosis is a pathological feature of chronic kidney injury that contributes to renal failure. This study aimed to explore the effects of Hirudin on renal fibrosis. The antifibrotic effect of Hirudin was evaluated using unilateral ureteral obstruction (UUO) rats and TGF-β-treated HK-2 cells. The autophagy inhibitor 3-methyladenine was used to further explore the potential mechanism. Hirudin treatment significantly reduced UUO-induced elevations in blood urea nitrogen, creatinine, and alpha-smooth muscle actin (α-SMA) levels and improved kidney injury and renal fibrosis. In addition, Hirudin markedly decreased NLRP3 inflammasome-related protein expression and increased autophagy-related protein expression in the kidneys of UUO rats. Hirudin significantly increased cell viability, reduced α-SMA and NLRP3 inflammasome-related protein levels, and increased autophagy-related protein levels in TGF-β-treated HK-2 cells. However, the effects of Hirudin were counteracted by 3-methyladenine. In conclusion, Hirudin inhibits the activation of NLRP3 inflammasome by inducing autophagy to improve renal fibrosis.

To enhance the transformation efficiency of Bacillus subtilis Marburg 168 using PCR DNA fragments, we optimized the competent cell preparation by adding Mn2+ to the competence medium. This Mn2+ addition promoted both cell growth and increased transformation frequency. Moreover, we determined the necessary length of the homologous sequence on each end to achieve practically sufficient transformation through double crossover recombination.

Whey is a byproduct in the manufacturing of dairy products. Its use is limited, and its nutrients make it expensive for its disposal. Therefore, we attempted to develop its upcycling method. When the Aspergillus oryzae RIB40 strain was cultured in whey, more than 75% of lactose, its major saccharide, remained after 7 days of cultivation. However, when lactase preparation was added, most sugars were efficiently removed, implying that lactase is essential for consuming whey nutrients. We created an A. oryzae lactase-overexpressing strain by introducing the tef1 promoter and lactase gene into RIB40. When cultured in whey, the transformant completely consumed its saccharides. The biological oxygen demand, chemical oxygen demand, total nitrogen concentration, and total phosphorus concentration of the whey decreased by 90%, 91%, 62%, and 95%, respectively, through this fermentation. The transformant can be considered "self-cloning" and is not subject to regulations on recombinant organisms in countries including Japan.

Glycoside hydrolase family 27 (GH27) consists primarily of exo-acting enzymes, including α-galactosidase, α-N-acetylgalactosaminidase, β-l-arabinopyranosidase, and isomalto-dextranase. Here, we examined the gene expression profiles and biochemical characteristics of a multi-domain protein, Fjoh_4436 (named FjGH27A), which contains a GH27 catalytic domain and is encoded upstream of the previously described branched dextran utilization locus in Flavobacterium johnsoniae. Expression of this gene increased 7.7-fold when cultured with α-(1→2)- and α-(1→3)-branched dextran, produced by Leuconostoc citreum S-32, as the carbon source, compared with cultures using glucose or linear dextran. The catalytic domain of FjGH27A exhibited hydrolytic activity against linear dextran and produced isomaltooligosaccharides of various sizes in an endo-acting manner. The enzyme showed the highest activity toward linear dextran at pH 5.5-6.0 and 25 °C-30 °C. This represents the first identification of an endo-acting enzyme in the GH27 family, offering new insights into the mechanism of branched dextran degradation mediated by FjGH27A.

This study investigated the saponin fraction (SF) from Panax japonicus aerial parts against NAFL. The SF was isolated from P. japonicus aerial parts using D-101 macroporous resin, containing 6 identified ginsenosides. The SF could reduce the accumulation of lipids in liver and the hepatic index, decrease the levels of TC and triglyceride in serum and in liver, and decrease the levels of Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) in serum. Additionally, the SF could increase the SOD and GSH-Px levels while reducing the levels of Malondialdehyde (MDA), Tumor Necrosis Factor (TNF-α), Interleukin (IL-1β), and Free Fatty Acids (FFA) in the liver. After treatment with SF, the AMP-activated protein kinase (AMPK)/ACC signaling pathway was activated through phosphorylation of AMPK and ACC, and the expression of HMG-CoA reductase (HMGCR) was inhibited, thereby reducing lipids synthesis. The results indicated that SF could treat NAFL by up-regulating the AMPK/ACC signaling pathway while inhibiting the expression of HMGCR.

β-Glucosidase converts soybean isoflavone glucosides to aglycones, and Bacillus subtilis strain Miyagino shows remarkably lower activity than B. subtilis strain 168, when cultured in a soybean-based medium. The inactivation of bglH, a key β-glucosidase-related gene, was found in B. subtilis strain Miyagino. This study indicates that the decreased bglH expression significantly affects the low β-glucosidase activity of B. subtilis strain Miyagino.

Zinc (Zn), Copper (Cu), and Manganese (Mn) are micronutrients that are essential for biological functions. They act as cofactors for numerous proteins and serve as signaling molecules. Although recent studies have significantly advanced our understanding of the individual roles of these metals, their homeostatic interactions remain largely unclear, except for a few well-documented cases, most notably the well-known competition between Zn and Cu for intestinal absorption. Moreover, recent research in vertebrates has suggested that Mn metabolism is closely linked to Zn metabolism in various cellular processes. Investigating the regulatory mechanisms governing homeostasis of essential trace metals is crucial for elucidating their functions in cellular systems. In this review, we provide a brief overview of the recent advances in understanding the competition between Cu, Mn, and Zn, with a particular focus on the interaction of Zn with the other two metals.

Labor shortages threaten global apple production, thereby encouraging new strategies to improve orchard management. The growth of columnar apples, controlled by the MdDOX-Co gene, enables vertical growth with minimal lateral branching, allowing for high-density planting and easier harvesting. MdDOX-Co encodes 2-oxoglutarate-dependent dioxygenase (2ODD, DOX). This study aimed to identify selective chemical inhibitors of MdDOX-Co. We synthesized the parental C6-based analogs featuring a heterocyclic 1,3,4-oxathiazol-2-one ring and evaluated their inhibitory activity. Compounds retaining the 1,3,4-oxathiazol-2-one core exhibited strong in vitro inhibition and promoted seedling elongation in MdDOX-Co overexpressing Arabidopsis. Structure-activity analysis confirmed that the 1,3,4-oxathiazol-2-one ring was essential, with tolerance for side-chain variations, including bulky groups. Selectivity assays indicated minimal off-target effects on the related 2ODD enzymes. Molecular modeling suggested the compatibility of the lead compounds with the MdDOX-Co active site. These findings encourage us to develop MdDOX-Co-targeted agrochemicals to chemically regulate tree architecture and enhance productivity during apple cultivation.