Sheng wu gong cheng xue bao = Chinese journal of biotechnology最新文献

To address the issues of low efficiency and susceptibility to high-concentration pollutants in nitrite nitrogen (NO₂^--N) removal in existing technologies, screening functional bacterial strains with high NO₂^--N removal capacity has become one of the effective solutions. This study focused on a strain, Paracoccus shandongensis wg2, isolated from activated sludge in the wastewater of propylene oxide saponification, investigating its nitrogen removal mechanism through nitrogen balance analysis and isotopic tracing. The results demonstrated that the strain adopted a nitrogen removal metabolic pathway belonging to the nitrite denitrification type. Under anaerobic conditions, the strain exhibited remarkable nitrite nitrogen (NO₂^--N) removal efficiency, achieving over the elimination rate over 98.00% within 48 h. Through process parameter optimization, the optimal denitrification conditions were determined as follows: glucose as the carbon source, C/N ratio of 5, initial pH 7.0, temperature of 30 ℃, and rotation speed of 170 r/min. Under these optimized conditions, strain wg2 accomplished complete NO₂^--N (55 mg/L) removal within 10 h. This research not only provides a microbial resource for the biological treatment of nitrogen-containing wastewater but also offers significant practical guidance for addressing high-concentration nitrite wastewater.

Sterols play a crucial role in the growth and development of organisms, as well as in the construction of cell membranes. The biosynthesis of sterols is a complex metabolic process involving multiple enzymatic reactions. The removal of two methyl groups at the C-4 position by the sterol-C4-methyloxidase-like (SC4MOL) is an important step in sterol functionalization. This paper provides a systematic review of the critical role of SC4MOL in sterol biosynthesis. It specifically elaborates on SC4MOL in terms of the composition, catalytic mechanism, and functional diversity across different organisms in processes such as growth, development, and resistance to diseases and stress. The review lays a foundation for further research into the regulation of sterol metabolism.

Enzyme-mediated degradation of plastics is considered as a promising solution for addressing escalating plastic pollution. Extensive studies have identified diverse plastic-degrading enzymes from typical habitats, extreme environments, and different hosts. However, the short co-evolution period between microbes and plastics limits the natural evolution of specific plastic-degrading enzymes. The identified plastic-degrading enzymes mainly belong to the carbohydrate esterase (CE) and auxiliary activity (AA) enzyme families, being involved in lignin degradation. Consequently, lignin degradation-related enzymes represent a promising resource for the discovery of novel plastic-degrading enzymes. The available studies on the catalytic mechanisms and applications of plastic-degrading enzymes mainly focused on IsPETase and leaf-branch compost cutinase (LCC). Systematic insights into non-hydrolytic plastic-degrading enzymes remain scarce. This review summarizes the types and catalytic mechanisms of plastic-degrading enzymes related to C-O and C-C backbone plastics, and advancements in their screening strategies, engineering modifications, and applications over the past five years. These findings contribute to the collaborative evolution of enzyme research in terms of mechanisms and application innovation. Furthermore, this review establishes a theoretical framework for plastic pollution control.

The ubiquitin-proteasome system (UPS) serves as the central mechanism for protein degradation in eukaryotic cells. Deubiquitinases (DUBs), which maintain protein stability and function by removing ubiquitin chains play a key role in protein cycling. Consequently, a DUB-targeting chimera (DUBTAC) technology has emerged. A DUBTAC consists of three components: a protein-targeting ligand, a DUB recruiter, and a linker connecting them. A DUBTAC can simultaneously bind to its targeted protein and DUB and induce the DUB to cleave the ubiquitin chains, thereby restoring the protein function by stabilizing the target protein. The DUBTAC technology provides a novel research strategy involving targeted protein stabilization for conventionally "undruggable" proteins that are abnormally degraded. Compared with other mature technologies, such as proteolysis-targeting chimera (PROTAC) and molecular glue degrader technologies, the DUBTAC technology has the unique advantages of targeting and stabilizing tumor suppressors, thus showing high potential for cancer therapy. However, it is still in the early stage of development with few systematic summaries of recent research achievements. This review introduces the basic concepts, critical design, and research considerations of DUBTACs, summarizes the latest research advances in DUBTAC technology for antitumor drug development, and discusses the development strategies and clinical application prospects of DUBTACs in the future, aiming to provide more directions for research on this technology.

Soybean isoflavones (SIFs), a class of polyphenolic compounds, exhibit a range of beneficial biological activities, including immunomodulation, antioxidant effects, anticancer properties, and the promotion of reproduction and growth. Their potential application in animal husbandry has garnered increasing research interest. However, natural SIFs are predominantly present as biologically inactive glycosides, with only minimal amounts existing in the highly active aglycone form. Enhancing their bioavailability, therefore, necessitates a biotransformation process. Microbial fermentation emerges as an efficient, eco-friendly, and cost-effective strategy for this purpose, capable of transforming inactive glycosides into bioactive aglycones and other metabolites through reactions such as deglycosylation, demethylation, dehydroxylation, and reduction. This review elucidates the structural characteristics and metabolic pathways of SIFs, summarizes recent advances in their microbial transformation by various microorganisms (e.g., lactic acid bacteria, fungi, and Bacillus species), and critically assesses the efficacy and underlying mechanisms of SIFs in enhancing animal productivity, reproductive performance, and immune function. The aim is to provide valuable insights for the advanced application of SIFs in the animal husbandry and food industries.

D-amino acids, chiral molecules with unique physiological activities, present widely distribution in microorganisms, plants, and animals. With the deepening of research, D-amino acids are playing increasingly important roles in food, pharmaceuticals, agrochemicals, cosmetics and other fields. However, the natural abundance of D-amino acids is low. Chemical synthesis methods suffer from low stereoselectivity, serious environmental pollution, and high production costs, which limit their industrial application. Enzymatic synthesis has emerged as a cutting-edge research focus for D-amino acid production due to its high stereoselectivity, mild reaction conditions, and environmental friendliness. Currently, enzymes commonly used for D-amino acid synthesis include D-amino acid dehydrogenase, L-amino acid oxidase, D-amino acid aminotransferase, D-aminoacylase, D-hydantoinase, and D-carbamoylase. These enzymes employ various mechanisms to convert substrates or resolve racemic mixtures, or establish multi-enzyme cascade reactions to synthesize diverse D-amino acids and their derivatives. This review summarizes the latest advances in the enzymatic synthesis of D-amino acids, explores the catalytic mechanisms and optimization strategies of various enzymes, and examines the performance of these enzymes in practical applications, providing theoretical support and technical guidance for the efficient and green synthesis of D-amino acids.

Petrochemical contaminants pose serious threats to the environment, and bioremediation is one of the main approaches for the remediation of petrochemical contamination. However, conventional bioremediation processes often have limitations, such as prolonged duration and low efficiency. There is an urgent need to develop new bioremediation technologies to improve the degradation effect on petrochemical contaminants. Constructing engineered microorganisms through synthetic biology for contaminant degradation has emerged as a cutting-edge technology and a popular research focus to address environmental challenges. This review introduces the hazards of petrochemical contamination and the shortcomings of existing remediation technologies and summarizes the research progress in biosensors, engineered strains for degradation, and synthetic microbial communities for petrochemical contamination remediation. Subsequently, it expounds on the problems existing in engineered microorganisms during the remediation and proposes possible solutions. Finally, this paper makes an outlook on the application prospects of synthetic biology in this field. The continuous development of synthetic biology in the field of environmental remediation is expected to further improve the efficiency of bioremediation, achieve the best remediation effect, and provide more feasible solutions for the green development and environmental protection work in China.

Synthetic biology and biomanufacturing, two cutting-edge directions in biotechnology, are rapidly developing and regarded as the core driving force of the "third biotechnology revolution". They reshape the paradigm of industrial manufacturing through designing life and making useful products and promote the industrial revolution in healthcare, energy, agriculture, and environmental protection. However, the development of synthetic biology and biomanufacturing, especially in terms of designing life for practical applications, still faces challenges such as insufficient screening capabilities, culture heterogeneity, and limited regulation and control over biological processes. Microfluidics, with its micro-scale fluid manipulation capability, offers new solutions to these challenges through single-cell precision, high-throughput screening, and rapid iteration. This study reviews microfluidics regarding the applications in the design-build-test-learn (DBTL) cycle of synthetic biology and the role in intensifying biomanufacturing processes, including upstream stain and culture improvement and downstream processing integration and optimization. Then, some case studies of microfluidics-driven synthetic biology and biomanufacturing in the fields of chemicals & materials, agrifood, and healthcare were summarized. Finally, the bottlenecks of microfluidics in synthetic biology and biomanufacturing, such as micro-scale amplification and chip materials, were analyzed, and the future directions, including its role as an enabling technology, interdisciplinary integration, and AI-driven intelligent systems, were discussed. This review is expected to serve as a valuable reference for further innovation in synthetic biology and biomanufacturing.

Common wheat (Triticum aestivum L.) is one of the main staple food crops in China. The protein quality of wheat grains directly determines the processing quality and nutritional quality of flour foods. With the growth of the population, the upgrading of the dietary structure, and the transformation of the demand in the food industry, the research on wheat in China has shifted from simply pursuing high yields to a new stage of coordinated improvement of yield, quality, and nutrition. This article systematically reviews the main progress in the research on the quality of wheat grain protein, including the identification of gluten proteins and high-quality subunits, the analysis of the expression regulation of gluten protein genes, the mining of quality-related genes based on multi-omics, the impact of the interaction between proteins and other components on processing characteristics, and the application of biotechnology in the breeding of high-quality wheat. In view of the complex evaluation process and environmental susceptibility of wheat quality traits, as well as the goal of achieving synergistic optimization of nutrition and functionality in protein quality research under the National Whole Grain Action Plan, we examine the challenges and future development prospects of cutting-edge technologies such as marker-assisted selection and gene editing. This review aims to provide theoretical support for the upgrading of the high-quality wheat industry.

The objective of this study was to prepare polyclonal antibodies (pAb) against the Mycoplasma hyopneumoniae (Mhp) membrane protein Mhp271 and systematically evaluate their immunological characteristics and potential applications. The mhp271 gene (3 156 bp) was amplified by PCR and cloned into the prokaryotic expression vector pMAL-c5x to construct the recombinant plasmid pMAL-c5x-mhp271. After verification by PCR and DNA sequencing, the construct was transformed into Escherichia coli BL21(DE3) competent cells, and the expression of recombinant Mhp271 (rMhp271) was induced with IPTG. Western blotting revealed a specific band at approximately 160 kDa, confirming successful expression of rMhp271. Purified rMhp271 was emulsified and used to immunize BALB/c mice three times. Serum samples were collected one week after the final immunization, and anti-Mhp271 specific pAb was isolated. To assess the reactivity of the anti-Mhp271 pAb, we used porcine alveolar macrophages (PAMs) to establish a cell model of Mhp infection. After Mhp infection for 12 h, Western blotting and indirect immunofluorescence assay (IFA) were employed to assess protein expression. Western blotting results showed a specific band at approximately 118 kDa in the lysate from Mhp-infected PAMs, while no corresponding band was detected in the uninfected control group. IFA demonstrated distinct green fluorescence signals in infected cells, whereas no fluorescence was observed in the uninfected control group. Furthermore, the potential of anti-Mhp271 pAb to inhibit Mhp infection was evaluated through in vitro blocking assays. Mhp was pre-incubated with either 100-fold diluted anti-Mhp271 serum (experimental group) or negative serum (control group) for 30 min before being inoculated into PAMs for 12 h. TaqMan real-time quantitative PCR indicated a significant reduction in Mhp load in the experimental group compared with the control group, which was further confirmed by the weakened fluorescence in IFA. Overall, the prepared anti-Mhp271 pAb demonstrated good reactogenicity and anti-infective activity, being suitable for immunological detection methods such as Western blotting and IFA.