Biotechnology Journal最新文献

Synechocystis sp., a prominent model organism among cyanobacteria, is renowned for its efficient CO₂ utilization to produce valuable metabolites, positioning it as a promising alternative to traditional heterotrophic microbes for sustainable bioproduction. Recent advances in Synechocystis-based cell factories have significantly improved synthetic biology design and the bioproduction of high-value biochemicals. In this review, we provide an updated bioinformatics overview of Synechocystis sp. and comprehensively summarize the latest advancements in its synthetic biology applications. Additionally, we highlight recent progress and challenges in scaling up and industrialization, while proposing future research directions, including the integration of omics strategies. These developments are expected to drive the application of cyanobacteria in industrial biotechnology and contribute to the advancement of sustainable, low-carbon, and high-efficiency bioproduction systems.

Heparosan, a glycosaminoglycan (GAG) derived from bacterial capsular polysaccharide (CPS), shares a similar backbone with both clinically utilized heparin and heparan sulfate (HS). This facilitates its transformation into heparin/HS via chemoenzymatic strategies. Currently, the purification process of heparosan, followed by N-deacetylation and N-sulfation, requires executing several complex steps prone to the unintended loss of polysaccharides and environmental risks. In this study, heparosan extracted from fermentation broth underwent immediate N-deacetylation and N-sulfation before DEAE chromatography purification. The results showed that the recovery of N-deacetylated heparosan increased from less than 40% to 93.6% with negligible contaminants. After sulfation, the overall recovery yield of N-sulfo heparosan was 76.0%. The number average molecular weight (M_n) and weight average molecular weight (M_W) of N-sulfo heparosan were ascertained to be 5.2 and 10.7, respectively, with a polydispersity index (PDI) value of 2.1. The assessment of elemental composition revealed that the efficiency of N-sulfation was 84%, which aligns with that of commercial heparin. The strategy delineated in this investigation avoids the substantial loss of N-deacetylated polysaccharides resulting from the complex procedures. Furthermore, the study avoids using harmful organic solvents in preparing heparosan, thereby promoting the in vitro green synthesis of heparin-like polysaccharides and analogous pharmaceutical compounds.

Virus filtration is a critical step to ensure the safety of antibody-based therapeutics. Due to the stringent performance requirements, commercially available virus filtration membranes are limited, and studies on virus retention behavior across different antibodies remain scarce, partly due to the high cost of these biologics. Herein, we comprehensively evaluated a newly developed virus filtration membrane, UF-Viremoval-Plus, by benchmarking it against leading commercial virus filters. The results demonstrate that UF-Viremoval-Plus exhibits superior antifouling properties and virus retention performance, which are attributed to its less negative charge, higher hydrophilicity, gradient pore structure and funnel-shaped geometry. We further investigated the effects of key process parameters, including pH, ionic strength, antibody type, and concentration, on membrane flux and virus removal efficiency. The membrane maintained stable operation under varying pressures and process disturbances, consistently achieving virus removal levels above 4 log reduction value, with no evidence of virus breakthrough. However, significant shifts in feed solution pH or ionic strength, as well as membrane fouling caused by high protein concentrations, affected virus removal. These observations are governed by complex membrane-protein-virus interactions. This work provides theoretical insights for the rational design of virus filtration membrane microstructures and the optimization of viral clearance processes in biopharmaceutical manufacturing.

Increasing evidence supports the human sodium-coupled citrate transporter (hNaCT) as a potential therapeutic target for metabolic syndrome and early infantile epileptic encephalopathy type 25 (EIEE25). While isotopic tracers remain the reference method for evaluating citrate transport, the need for specialized equipment and regulatory approval restricts their widespread use. Here, we report the development and validation of a robust, fluorescent-based assay to evaluate hNaCT-mediated citrate transport in live cells at both single-cell and high-throughput levels. This method utilizes a baculoviral vector to modify HEK293 cells to co-express a genetically encoded citrate sensor (Citron1) and the hNaCT. This cell-based platform enabled real-time monitoring of citrate transport using fluorescent microscopy and a standard multiwell plate reader. A key strength of this approach is its ability to assess citrate transport in the same cells before and after experimental interventions. Accordingly, this approach enables the functional characterization of hNaCT, including its pharmacological inhibitors and genetic variants with altered activity. Overall, the method provides a reliable assessment of citrate transport and offers a versatile platform suitable for identifying novel lead compounds for the therapeutic modulation of hNaCT.

Polyurethane (PU), as one of the most widely produced and consumed plastics globally, has led to severe environmental pollution and resource wastage due to the substantial amount of solid waste and microplastics it generates. Plastic recycling technologies that employ microorganisms and enzymes as catalysts not only enable efficient depolymerization of PU wastes into monomers while offering notable advantages, such as mild reaction conditions and avoidance of organic solvents. These features position enzymatic and microbial processes as a promising solution for achieving green and low-carbon end-of-life treatment of PU. However, PU biodegradation technologies are still in the early stages of fundamental research and face multiple challenges, including limited biocatalytic resources, low efficiency of enzymatic depolymerization, and difficulties in recovery and reuse. This review systematically summarizes the chemical structures of PU, recent advances in PU-degrading microbes and enzymes. It further discusses the biological metabolic pathways of depolymerized monomers, as well as current resource utilization strategies via closed-loop recycling and upcycling. The aim of this review is to provide theoretical guidance and novel insights into the efficient biodegradation and recovery of PU, thereby supporting the development of a circular plastic economy and contributing to global sustainability and carbon neutrality goals.

Two persistent challenges in adeno-associated virus (AAV) manufacturing are AAV particle aggregation and the separation of full and empty AAV capsids in ion-exchange (IEX) chromatography processes, which add to AAV purification, formulation, and quality control challenges. AAV empty capsids and AAV aggregates are both considered product-related impurities by regulatory agencies. AAV full capsids, which contain the genetic payload, is the AAV species that has the therapeutic value. Thus, it is necessary to continuously improve the control of AAV aggregation and the ratio of full to empty capsids during AAV downstream bioprocessing. We investigated a novel approach that significantly improves aggregation control of AAV serotype 2 (AAV2). The novel approach consisted of a systematic study, involving Design of Experiment (DoE), using common formulation excipients (namely, small sugars and ionic salts) to understand the effect of critical process parameters (excipient type, excipient concentration, and pH) on a critical quality attribute (AAV aggregates). With this approach, we observed a statistically significant reduction in AAV2 particle aggregation in solution. Results suggest that this aggregation-control approach could provide insight into potentially being able to create a new strategy for improving the separation of full and empty AAV2 capsids in anion exchange (AEX) chromatography.

The Yellow River Basin, as a crucial water and ecological zone, is threatened by environmental contamination from the Bayan Obo tailings dam located just 13 km away. Based on the Microbial-Induced Calcite Precipitation, this research used a combined approach of bio-mineralization and bio-sorption to bio-remediate the rare earth elements (REEs) and their mixed contaminants. Optimal conditions for soil solidification and stabilization are determined through solution pretests. Comparative analyses of adsorption, mineralization, and their combined processes were conducted in soil experiments. Evaluating using the results of speciation analysis. Following bioremediation, the adsorption–mineralization group involving indigenous bacteria, Bacillus oceanicus, exhibited the best performance. In this group, the average comprehensive reduction in exchangeable forms of Zn, Pb, La, and Ce was 52.02%, which is 2.9 times that of the adsorption group and 1.3 times that of the mineralization group under the same environmental conditions. These results indicate that the biogenic carbonates and isomorphic lattice substitutions generated through the bioption and bio-mineralization process contribute to the solidification/stabilization of REEs and their mixed contaminants. This approach holds significant importance for environmental protection and ecological restoration in the Yellow River Basin, particularly in the middle and lower reaches of the Yellow River.

Phenolic compounds from lignin degradation in harsh pretreatment of lignocellulose persistently exist at low concentrations in hydrolysates even after standard detoxification and enzymatic hydrolysis. This study found that minor phenolic compounds in dry acid-pretreated and biodetoxified wheat straw hydrolysates were the key inhibitors of Escherichia coli (E. coli). Multiple E. coli strains exhibited poor cell growth and metabolic activity in wheat straw hydrolysates with the presence of minor phenolics. However, the cell growth and metabolic activity of E. coli strains were significantly recovered with the declining phenolic content. Several recombinant E. coli strains successfully fermented 22.17 g/L of ethanol and synthesized 12.04 g/L of cadaverine using wheat straw hydrolysates after the removal of minor phenolics. These findings highlight the critical role of phenolic compounds in the inhibition of E. coli strains and provide a foundation for E. coli recombinants in biorefinery fermentations for biofuel and biochemical productions.

Cardiovascular diseases (CVDs) remain the predominant cause of morbidity and mortality worldwide, with limited curative treatment options for advanced heart failure (HF). While pharmacological and surgical interventions have improved survival, they often fail to regenerate damaged myocardial tissue. Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic modality in regenerative medicine, particularly for cardiac repair. This review highlights the role of MSCs in addressing the unmet clinical need for myocardial regeneration, focusing on their biological characteristics, mechanisms of action, and therapeutic applications in various CVDs. MSCs, derived from bone marrow or adipose tissue, exhibit immunomodulatory, anti-fibrotic, and pro-angiogenic properties that facilitate cardiac tissue repair. Their ability to be used in an allogeneic, off-the-shelf format offers practical advantages for large-scale clinical use. However, several challenges, including poor survival post-transplantation, inter-source variability, and complex interactions with the ischemic microenvironment, must be addressed to maximize therapeutic efficacy. Emerging technologies such as gene editing, exosome-based delivery, tissue engineering, and 3D bioprinting offer promising strategies to enhance MSC therapy. This review concludes by outlining future directions for standardization, clinical translation, and optimization of MSC-based cardiac regenerative therapies.