A Magnetosome-Based Platform for Flow Biocatalysis

Biominerals and Bioinspired Materials in Biosensing: Recent Advancements and Applications

Inspired by nature's remarkable ability to form intricate minerals, researchers have unlocked transformative strategies for creating next-generation biosensors with exceptional sensitivity, selectivity, and biocompatibility. By mimicking how organisms orchestrate mineral growth, biomimetic and bioinspired materials are significantly impacting biosensor design. Engineered bioinspired materials offer distinct advantages over their natural counterparts, boasting superior tunability, precise controllability, and the ability to integrate specific functionalities for enhanced sensing capabilities. This remarkable versatility enables the construction of various biosensing platforms, including optical sensors, electrochemical sensors, magnetic biosensors, and nucleic acid detection platforms, for diverse applications. Additionally, bioinspired materials facilitate the development of smartphone-assisted biosensing platforms, offering user-friendly and portable diagnostic tools for point-of-care applications. This review comprehensively explores the utilization of naturally occurring and engineered biominerals and materials for diverse biosensing applications. We highlight the fabrication and design strategies that tailor their functionalities to address specific biosensing needs. This in-depth exploration underscores the transformative potential of biominerals and materials in revolutionizing biosensing, paving the way for advancements in healthcare, environmental monitoring, and other critical fields.

Strategies for Automated Enzymatic Glycan Synthesis (AEGS)

Glycans are the most abundant biopolymers on earth and are constituents of glycoproteins, glycolipids, and proteoglycans with multiple biological functions. The availability of different complex glycan structures is of major interest in biotechnology and basic research of biological systems. High complexity, establishment of general and ubiquitous synthesis techniques, as well as sophisticated analytics, are major challenges in the development of glycan synthesis strategies. Enzymatic glycan synthesis with Leloir-glycosyltransferases is an attractive alternative to chemical synthesis as it can achieve quantitative regio- and stereoselective glycosylation in a single step. Various strategies for synthesis of a wide variety of different glycan structures has already be established and will exemplarily be discussed in the scope of this review. However, the application of enzymatic glycan synthesis in an automated system has high demands on the equipment, techniques, and methods. Different automation approaches have already been shown. However, while these techniques have been applied for several glycans, only a few strategies are able to conserve the full potential of enzymatic glycan synthesis during the process - economical and enzyme technological recycling of enzymes is still rare. In this review, we show the major challenges towards Automated Enzymatic Glycan Synthesis (AEGS). First, we discuss examples for immobilization of glycans or glycosyltransferases as an important prerequisite for the embedment and implementation in an enzyme reactor. Next, improvement of bioreactors towards automation will be described. Finally, analysis and monitoring of the synthesis process are discussed. Furthermore, automation processes and cycle design are highlighted. Accordingly, the transition of recent approaches towards a universal automated glycan synthesis platform will be projected. To this end, this review aims to describe essential key features for AEGS, evaluate the current state-of-the-art and give thought- encouraging impulses towards future full automated enzymatic glycan synthesis.

Will tomorrow's mineral materials be grown?

Biomineralization, the capacity to form minerals, has evolved in a great diversity of bacterial lineages as an adaptation to different environmental conditions and biological functions. Microbial biominerals often display original properties (morphology, composition, structure, association with organics) that significantly differ from those of abiotically formed counterparts, altogether defining the 'mineral phenotype'. In principle, it should be possible to take advantage of microbial biomineralization processes to design and biomanufacture advanced mineral materials for a range of technological applications. In practice, this has rarely been done so far and only for a very limited number of biomineral types. This is mainly due to our poor understanding of the underlying molecular mechanisms controlling microbial biomineralization pathways, preventing us from developing bioengineering strategies aiming at improving biomineral properties for different applications. Another important challenge is the difficulty to upscale microbial biomineralization from the lab to industrial production. Addressing these challenges will require combining expertise from environmental microbiologists and geomicrobiologists, who have historically been working at the forefront of research on microbe-mineral interactions, alongside bioengineers and material scientists. Such interdisciplinary efforts may in the future allow the emergence of a mineral biomanufacturing industry, a critical tool towards the development more sustainable and circular bioeconomies.

Precisely Navigated Biobot Swarms of Bacteria Magnetospirillum magneticum for Water Decontamination

Hybrid biological robots (biobots) prepared from living cells are at the forefront of micro-/nanomotor research due to their biocompatibility and versatility toward multiple applications. However, their precise maneuverability is essential for practical applications. Magnetotactic bacteria are hybrid biobots that produce magnetosome magnetite crystals, which are more stable than synthesized magnetite and can orient along the direction of earth's magnetic field. Herein, we used Magnetospirillum magneticum strain AMB-1 (M. magneticum AMB-1) for the effective removal of chlorpyrifos (an organophosphate pesticide) in various aqueous solutions by naturally binding with organic matter. Precision control of M. magneticum AMB-1 was achieved by applying a magnetic field. Under a programed clockwise magnetic field, M. magneticum AMB-1 exhibit swarm behavior and move in a circular direction. Consequently, we foresee that M. magneticum AMB-1 can be applied in various environments to remove and retrieve pollutants by directional control magnetic actuation.

Design of fusion enzymes for biocatalytic applications in aqueous and non-aqueous media

Biocatalytic cascades play a fundamental role in sustainable chemical synthesis. Fusion enzymes are one of the powerful toolboxes to enable the tailored combination of multiple enzymes for efficient cooperative cascades. Especially, this approach offers a substantial potential for the practical application of cofactor-dependent oxidoreductases by forming cofactor self-sufficient cascades. Adequate cofactor recycling while keeping the oxidized/reduced cofactor in a confined microenvironment benefits from the fusion fashion and makes the use of oxidoreductases in harsh non-aqueous media practical. In this mini-review, we have summarized the application of various fusion enzymes in aqueous and non-aqueous media with a focus on the discussion of linker design within oxidoreductases. The design and properties of the reported linkers have been reviewed in detail. Besides, the substrate loadings in these studies have been listed to showcase one of the key limitations (low solubility of hydrophobic substrates) of aqueous biocatalysis when it comes to efficiency and economic feasibility. Therefore, a straightforward strategy of applying non-aqueous media has been briefly discussed while the potential of using the fusion oxidoreductase of interest in organic media was highlighted.