Atomically precise graphene nanoribbons (GNRs) synthesized from the bottom-up exhibit promising electronic properties for high-performance field-effect transistors (FETs). The feasibility of fabricating FETs with GNRs (GNRFETs) has been demonstrated, with ongoing efforts aimed at further improving their performance. However, their long-term stability and reliability remain unexplored, which is as important as their performance for practical applications.
View Article and Find Full Text PDFMetabolic engineering reprograms cells to synthesize value-added products. In doing so, endogenous genes are altered and heterologous genes can be introduced to achieve the necessary enzymatic reactions. Dynamic regulation of metabolic flux is a powerful control scheme to alleviate and overcome the competing cellular objectives that arise from the introduction of these production pathways.
View Article and Find Full Text PDFCurr Opin Biotechnol
October 2020
Metabolic engineering seeks to reprogram cells to efficiently produce value-added chemicals. Traditionally, this is achieved by overexpressing the production pathway and/or knocking out competing endogenous pathways. However, limitations in some pathways are more effectively addressed through dynamic metabolic flux control to favor different cellular objectives over the course of the fermentation.
View Article and Find Full Text PDFAs synthetic biology and metabolic engineering tools improve, it is feasible to construct more complex microbial synthesis systems that may be limited by the machinery and resources available in an individual cell. Coculture fermentation is a promising strategy for overcoming these constraints by distributing objectives between subpopulations, but the primary method for controlling the composition of the coculture of production systems has been limited to control of the inoculum composition. We have developed a quorum sensing (QS)-based growth-regulation circuit that provides an additional parameter for regulating the composition of a coculture over the course of the fermentation.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2019
Metabolic engineering seeks to reprogram microbial cells to efficiently and sustainably produce value-added compounds. Since chemical production can be at odds with the cell's natural objectives, strategies have been developed to balance conflicting goals. For example, dynamic regulation modulates gene expression to favor biomass and metabolite accumulation at low cell densities before diverting key metabolic fluxes toward product formation.
View Article and Find Full Text PDFThe greatest obstacle to clinical application of cancer gene therapy is lack of effective delivery tools. Gene delivery vehicles must protect against degradation, avoid immunogenic effects and prevent off target delivery which can cause harmful side effects. PEGylated liposomes have greatly improved tumor localization of small molecule drugs and are a promising tool for nucleic acid delivery as the polyethylene glycol (PEG) coating protects against immune recognition and blood clearance.
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