Trends in biotechnology最新文献

Immune system functions play crucial roles in both health and disease, and these functions are regulated by their metabolic programming. The field of immune engineering has emerged to develop therapeutic strategies, including polymeric nanoparticles (NPs), that can direct immune cell phenotype and function by directing immunometabolic changes. Precise control of bioenergetic processes may offer the opportunity to prevent undesired immune activity and improve disease-specific outcomes. In this review we discuss the role that polymeric NPs can play in shaping immunometabolism and subsequent immune system activity through particle-mediated delivery of metabolically active agents as either structural components or cargo.

Despite the excellent advantages of biomicrorobots, such as autonomous navigation and targeting actuation, effective penetration and retention to deep lesion sites for effective therapy remains a longstanding challenge. Here, we present dual-engine cell microrobots, which we refer to as PR-robots, created by conjugating photosynthetic bacteria (PSB) with red blood cells (RBCs). The robots penetrate the tumor interior in swarms through combined hypoxic traction and ultrasound actuation (UA). The hypoxia-targeting ability of PSB induced PR-robot accumulation in the tumor region. Subsequently, programmable UA trapped the PR-robots to form bioswarms and traverse tissue obstacles, penetrating the tumor interior. The substantial influx of PR-robots into the tumor tissue promoted the formation of tumor-specific thrombus (TST). Finally, the PSB and TST synergistically improved the effect of photothermal therapy. Thus, these advantages of remote ultrasound control technology pave the way for various new therapies in practical biomedicine.

Inflammatory bowel disease (IBD) is a chronic relapsing immune-mediated inflammatory disorder of the alimentary tract without exact etiology. Mitochondrial reactive oxygen species (mtROS) derived from mitochondrial dysfunction impair intestinal barrier function, increase gut permeability, and facilitate immune cell invasion, and, therefore, are considered to have a pivotal role in the pathogenesis of IBD. Here, we reprogrammed regulatory T cell (Treg)-derived exosomes loaded with the antioxidant trace element selenium (Se) and decorated them with the synthetic mitochondria-targeting SS-31 tetrapeptide via a peptide linker. This linker can be cleaved by matrix metalloproteinases (MMPs) in inflammatory lesions. This actively targetable exosome-derived delivery system is protected from intestinal inflammation by scavenging excessive mtROS and preventing immunologically programmed cell death pyroptosis, necroptosis, and apoptosis, known as PANoptosis. Our results suggest that this engineered exosome delivery platform represents a promising targeted therapeutic strategy for the treatment of IBDs.

Advances in protein engineering-enabled enzyme immobilization technologies have significantly improved enzyme-electrode wiring in enzymatic electrochemical systems, which harness natural biological machinery to either generate electricity or synthesize biochemicals. In this review, we provide guidelines for designing enzyme-electrodes, focusing on how performance variables change depending on electron transfer (ET) mechanisms. Recent advancements in enzyme immobilization technologies are summarized, highlighting their contributions to extending enzyme-electrode sustainability (up to months), enhancing biosensor sensitivity, improving biofuel cell performance, and setting a new benchmark for turnover frequency in bioelectrocatalysis. We also highlight state-of-the-art protein-engineering approaches that enhance enzyme-electrode interfacing through three key principles: protein-protein, protein-ligand, and protein-inorganic interactions. Finally, we discuss prospective avenues in strategic protein design for real-world applications.

Secretion of high-value proteins and enzymes is fundamental to the synthetic biology economy, allowing continuous fermentation during production and protein purification without cell lysis. Most eukaryotic protein secretion is encoded by an N-terminal signal peptide (SP); however, the strong impact of SP sequence variation on the secretion efficiency of a given protein is not well defined. Despite high natural SP sequence diversity, most recombinant protein secretion systems use only a few well-characterised SPs. Additionally, the selection of promoters and terminators can significantly affect secretion efficiency, yet screening numerous genetic constructs for optimal sequences remains inefficient. Here, we adapted a yeast G-protein-coupled receptor (GPCR) biosensor, to measure the concentration of a peptide tag that is co-secreted with any protein of interest (POI). Thus, protein secretion efficiency can be quantified via induction of a fluorescent reporter that is upregulated downstream of receptor activation. This enabled high-throughput screening of over 6000 combinations of promoters, SPs, and terminators, assembled using one-pot Combinatorial Golden Gate cloning. We demonstrate this biosensor can quickly identify best combinations for secretion and quantify secretion levels. Our results highlight the importance of SP optimisation as an initial step in designing heterologous protein expression strategies, demonstrating the value of high-throughput screening (HTS) approaches for maximising secretion efficiency.

Biotechnology is widely used in bioproduction to transform waste into valuable products. A comprehensive understanding of the kinetics involved is crucial for optimizing system designs. In this review, we explore various kinetics models (e.g., the Gompertz, Logistic, Cone, first-order, Monod, and Andrews models) used in describing bioproduction processes. We focus on their interpretation and applications in microbial growth, bioproduct formation, substrate consumption, and the factors influencing bioproduction processes. We provide guidelines for selecting appropriate kinetics models, emphasizing their suitability for different kinetic processes under varying conditions. Additionally, we discuss the importance of statistical parameters in evaluating model performance. This review presents a framework for applying these models to effectively predict and optimize bioproduction systems.

Autotrophic microbial electrosynthesis (MES) processes are mainly based on organisms that rely on carbon dioxide (CO₂) as an electron acceptor and typically have low biomass yields. However, there are few data on the process and efficiencies of oxic MES (OMES). In this study, we used the knallgas bacterium Kyrpidia spormannii to investigate biomass formation and energy efficiency of cathode-dependent growth. The study revealed that the process can be carried out with the same electron efficiency as conventional gas fermentation, but overcomes disadvantages, such as the use of explosive gas mixtures. When accounting only for the electron input via electrical energy, a solar energy demand of 67.89 kWh kg^-1 dry biomass was determined. While anaerobic MES is ideally suited to produce methane, short-chain alcohols, and carboxylic acids, its aerobic counterpart could extend this important range of applications to not only protein for use in the food and feed sector, but also further complex products.

Oral administration of therapeutic peptides is limited by poor intestinal absorption. Use of engineered microorganisms as drug delivery vehicles can overcome the challenges faced by conventional delivery methods. The potential of engineered microorganisms to act synergistically with the therapeutics they deliver opens new horizons for noninvasive treatment modalities. This study engineered a probiotic yeast, Saccharomyces boulardii, to produce cell-penetrating peptides (CPPs) in situ for enhanced intestinal permeability. Four CPPs were integrated into the yeast chromosome: RRL helix, Shuffle, Penetramax, and PN159. In vitro tests on a Caco-2 cell model showed that three CPP-producing strains increased permeability without causing permanent damage. In vivo experiments on mice revealed that Sb PN159 administration over 10 days significantly increased FITC-dextran translocation into the bloodstream without causing inflammation. This study demonstrates, for the first time, the ability of an engineered microorganism to modulate host permeability for improved intestinal absorption of a macromolecule.

Alginate (Alg) is a versatile biopolymer for scaffold engineering and a bioink component widely used for direct cell printing. However, due to a lack of intrinsic cell-binding sites, Alg must be functionalized for cellular adhesion when used as a scaffold. Moreover, direct cell-laden ink 3D printing requires tedious disinfection procedures and cell viability is compromised by shear stress. Here, we demonstrate proof-of-concept, bioactive additive-free, microstructured Alg (M-Alg) scaffolds for neuron culture. The M-Alg scaffold was formed by introducing tetrapod-shaped ZnO (t-ZnO) microparticles into the ink as structural templates for interconnected channels and textured surfaces in the 3D-printed Alg scaffold, which were subsequently removed. Neurons exhibited significantly improved adhesion and growth on these M-Alg scaffolds compared with pristine Alg (P-Alg) scaffolds, with extensive neurite outgrowth and spontaneous neural activity, indicating the maturation of neuronal networks. These transparent, porous, additive-free Alg-based scaffolds with neuron affinity are promising for neuroregenerative and organoid-related research.

Biological processes are widely used technologies for water decontamination, but they are often limited by insufficient bioavailable carbon sources or biorecalcitrant contaminants. The recently developed photocatalytic material-microorganism hybrid (PMH) system combines the light-harvesting capacities of photocatalytic materials with specific enzymatic activities of whole cells, efficiently achieving solar-to-chemical conversion. By integrating the benefits of both photocatalysis and biological processes, the PMH system shows great potential for water decontamination. While recent reviews have focused primarily on its application in green energy development, this review emphasizes the latest advancements in PMH systems for water decontamination, covering various applications, key considerations, and synergistic mechanisms. This review aims to provide a fundamental understanding of the PMH system and explore its broader potential in environmental remediation.