Restructuring Biologically Assembled Binding Protein-Biopolymer Conjugates toward Advanced Materials.

Bacterial cell factories have been successfully engineered to efficiently assemble spherical polyhydroxybutyrate inclusions coated with functional proteins of interest. In these submicrometer-sized core-shell assemblies, proteins are bioconjugated to the polymer core, enabling bioengineering for uses as bioseparation resins, enzyme carriers, diagnostic reagents, and particulate vaccines. Here, we explore whether these functional protein-polymer assemblies could be restructured via dissolution and subsequent precipitation while retaining the functionality of the conjugated protein.

Bibliometric and scientometric analysis of PSMA-targeted radiotheranostics: knowledge mapping and global standing.

Purpose: Bibliometric and scientometric analyses provide a structured approach to large amounts of data, enabling the prediction of research theme trends over time, the detection of shifts in the boundaries of disciplines, and the identification of the most productive countries, institutions and scholars. In the context of prostate-specific membrane antigen (PSMA)-targeted radiotheranostics, no bibliometric or scientometric analysis has been published thus far. Therefore, this study was conducted to identify key contributors to the literature, assess the global scientific production of related research, and possibly predict future development patterns.

Translational fusion of terpene synthases for metabolic engineering: Lessons learned and practical considerations.

The step catalyzed by terpene synthases is a well-recognized and significant bottleneck in engineered terpenoid bioproduction. Consequently, substantial efforts have been devoted towards increasing metabolic flux catalyzed by terpene synthases, employing strategies such as gene overexpression and protein engineering. Notably, numerous studies have demonstrated remarkable titer improvements by applying translational fusion, typically by fusing the terpene synthase with a prenyl diphosphate synthase that catalyzes the preceding step in the pathway.

Characterization of novel mevalonate kinases from the tardigrade Ramazzottius varieornatus and the psychrophilic archaeon Methanococcoides burtonii.

Mevalonate kinase is central to the isoprenoid biosynthesis pathway. Here, high-resolution X-ray crystal structures of two mevalonate kinases are presented: a eukaryotic protein from Ramazzottius varieornatus and an archaeal protein from Methanococcoides burtonii. Both enzymes possess the highly conserved motifs of the GHMP enzyme superfamily, with notable differences between the two enzymes in the N-terminal part of the structures.

Product Profiles of Promiscuous Enzymes Can be Altered by Controlling In Vivo Spatial Organization.

Enzyme spatial organization is an evolved mechanism for facilitating multi-step biocatalysis and can play an important role in the regulation of promiscuous enzymes. The latter function suggests that artificial spatial organization can be an untapped avenue for controlling the specificity of bioengineered metabolic pathways. A promiscuous terpene synthase (nerolidol synthase) is co-localized and spatially organized with the preceding enzyme (farnesyl diphosphate synthase) in a heterologous production pathway, via translational protein fusion and/or co-encapsulation in a self-assembling protein cage.

DNA-origami-directed virus capsid polymorphism.

Viral capsids can adopt various geometries, most iconically characterized by icosahedral or helical symmetries. Importantly, precise control over the size and shape of virus capsids would have advantages in the development of new vaccines and delivery systems. However, current tools to direct the assembly process in a programmable manner are exceedingly elusive.

Production and Purification of Virus-Like Particles by Transient Expression in Plants.

Transient expression in plants has become a useful production system for virus-like particle (VLP) expression. High yields and flexible approaches to assembling complex VLPs, combine with ease of scale-up and inexpensive reagents to provide an attractive method for recombinant protein expression in general. Plants have demonstrated excellent capacity for the assembly and production of protein cages for use in vaccine design and nanotechnology.

Tunable Colocalization of Enzymes within P22 Capsid-Based Nanoreactors.

Virus-like particles (VLPs) derived from bacteriophage P22 have been explored as biomimetic catalytic compartments. colocalization of enzymes within P22 VLPs uses sequential fusion to the scaffold protein, resulting in equimolar concentrations of enzyme monomers. However, control over enzyme stoichiometry, which has been shown to influence pathway flux, is key to realizing the full potential of P22 VLPs as artificial metabolons.

Metabolic flux enhancement from the translational fusion of terpene synthases is linked to terpene synthase accumulation.

The end-to-end fusion of enzymes that catalyse successive steps in a reaction pathway is a metabolic engineering strategy that has been successfully applied in a variety of pathways and is particularly common in terpene bioproduction. Despite its popularity, limited work has been done to interrogate the mechanism of metabolic enhancement from enzyme fusion. We observed a remarkable >110-fold improvement in nerolidol production upon translational fusion of nerolidol synthase (a sesquiterpene synthase) to farnesyl diphosphate synthase.

Protein cargo encapsulation by virus-like particles: Strategies and applications.

Viruses and the recombinant protein cages assembled from their structural proteins, known as virus-like particles (VLPs), have gained wide interest as tools in biotechnology and nanotechnology. Detailed structural information and their amenability to genetic and chemical modification make them attractive systems for further engineering. This review describes the range of non-enveloped viruses that have been co-opted for heterologous protein cargo encapsulation and the strategies that have been developed to drive encapsulation.

Rapid Assembly and Prototyping of Biocatalytic Virus-like Particle Nanoreactors.

Protein cages are attractive as molecular scaffolds for the fundamental study of enzymes and metabolons and for the creation of biocatalytic nanoreactors for and use. Virus-like particles (VLPs) such as those derived from the P22 bacteriophage capsid protein make versatile self-assembling protein cages and can be used to encapsulate a broad range of protein cargos. encapsulation of enzymes within VLPs requires fusion to the coat protein or a scaffold protein.

Pore structure controls stability and molecular flux in engineered protein cages.

Protein cages are a common architectural motif used by living organisms to compartmentalize and control biochemical reactions. While engineered protein cages have featured in the construction of nanoreactors and synthetic organelles, relatively little is known about the underlying molecular parameters that govern stability and flux through their pores. In this work, we systematically designed 24 variants of the encapsulin cage, featuring pores of different sizes and charges.

The structure of a plant-specific partitivirus capsid reveals a unique coat protein domain architecture with an intrinsically disordered protrusion.

Persistent plant viruses may be the most common viruses in wild plants. A growing body of evidence for mutualism between such viruses and their hosts, suggests that they play an important role in ecology and agriculture. Here we present the capsid structure of a plant-specific partitivirus, Pepper cryptic virus 1, at 2.

Artificial Self-assembling Nanocompartment for Organizing Metabolic Pathways in Yeast.

Metabolic pathways are commonly organized by sequestration into discrete cellular compartments. Compartments prevent unfavorable interactions with other pathways and provide local environments conducive to the activity of encapsulated enzymes. Such compartments are also useful synthetic biology tools for examining enzyme/pathway behavior and for metabolic engineering.

Droplet shape control using microfluidics and designer biosurfactants.

Many uses of emulsion droplets require precise control over droplet size and shape. Here we report a 'shape-memorable' micro-droplet formulation stabilized by a polyethylene glycol (PEG)-modified protein -surfactant, the droplets are stable against coalescence for months and can maintain non-spherical shapes for hours, depending on the surface coverage of PEGylated protein. Monodisperse droplets with aspect ratios ranging from 1.

Cystatin Activity-Based Protease Profiling to Select Protease Inhibitors Useful in Plant Protection.

Protease inhibitors of the cystatin protein superfamily show potential in plant protection for the control of herbivorous pests. Here, we describe a cystatin activity-based profiling procedure for the selection of potent cystatin candidates, using single functional variants of tomato cystatin SlCYS8 and digestive Cys proteases of the herbivore insect Colorado potato beetle as a case study. The procedure involves the capture of target Cys proteases with biotinylated versions of the cystatins, followed by the identification and quantitation of captured proteases by mass spectrometry.

Protein cages and virus-like particles: from fundamental insight to biomimetic therapeutics.

Protein cages (viral and non-viral) found in nature have evolved for a variety of purposes and are found in all kingdoms of life. The main functions of these nanoscale compartments are the protection and delivery of nucleic acids e.g.

Emergence by Design in Self-Assembling Protein Shells.

The use of proteins and peptides as nanoscale components to generate new-to-nature physical entities holds great promise in biocatalysis, therapeutic or diagnostic delivery, and materials templating. The majority of functionalized particles have been based on existing structures found in nature. Developing biomimetic particles in this way takes advantage of highly evolved platforms for organization or encapsulation of functional moieties, offering significant advantages in stoichiometry, multivalency, and sequestration.

Innovation in plant-based transient protein expression for infectious disease prevention and preparedness.

Addressing new challenges in global health and biosecurity requires responsive and accessible platforms for the manufacture of preventative or therapeutic interventions. Transient protein expression in plants has evolved into a technology that offers a unique combination of rapid expression, inherent scalability, and flexibility in gene stacking with the capability to produce complex proteins and protein assemblies. Technical developments that have driven the progress of transient expression in plants include advanced expression systems, protein engineering and synthetic biology approaches to transiently, or stably, modify host plants.

pH Gradient Mitigation in the Leaf Cell Secretory Pathway Attenuates the Defense Response of to Agroinfiltration.

Partial neutralization of the Golgi lumen pH by the ectopic expression of influenza virus M2 proton channel is useful to stabilize acid-labile recombinant proteins in plant cells, but the impact of pH gradient mitigation on host cellular functions has not been investigated. Here, we assessed the unintended effects of M2 expression on the leaf proteome of infiltrated with the bacterial gene vector . An isobaric tags for relative and absolute quantification quantitative proteomics procedure was followed to compare the leaf proteomes of plants agroinfiltrated with either an "empty" vector or an M2-encoding vector.