Chimia最新文献

Genetic code expansion (GCE) can enable the site-selective incorporation of non-canonical amino acids (ncAAs) into proteins. GCE has advanced tremendously in the last decade and can be used to create biorthogonal handles, monitor and control proteins inside cells, study post-translational modifications, and engineer new protein functions. Since establishing our laboratory, our research has focused on applications of GCE in protein and enzyme engineering using aminoacyl-tRNA synthetase/tRNA (aaRS/tRNA) pairs. This topic has been reviewed extensively, leaving little doubt that GCE is a powerful tool for engineering proteins and enzymes. Therefore, for this young faculty issue, we wanted to provide a more technical look into the methods we use and the challenges we think about in our laboratory. Since starting the laboratory, we have successfully engineered over a dozen novel aaRS/tRNA pairs tailored for various GCE applications. However, we acknowledge that the field can pose challenges even for experts. Thus, herein, we provide a review of methodologies in ncAA incorporation with some practical commentary and a focus on challenges, emerging solutions, and exciting developments.

The addition of individual quanta of rotational excitation to a molecule has been shown to markedly change its reactivity by significantly modifying the intermolecular interactions. So far, it has only been possible to observe these rotational effects in a very limited number of systems due to lack of rotational selectivity in chemical reaction experiments. The recent development of rotationally controlled molecular beams now makes such investigations possible for a wide range of systems. This is particularly crucial in order to understand the chemistry occurring in the interstellar medium, such as exploring the formation of carbon-based astrochemical molecules and the emergence of molecular complexity in interstellar space from the reaction of small atomic and molecular fragments.

Nitro compounds play a crucial role in academia and industries, serving as building blocks for the synthesis of drugs, agrochemicals, and materials. Nitration, a fundamental process in organic synthesis, has undergone significant evolution since the 19th century. While electrophilic nitration dominates historically, recent decades have seen a focus on new reagents and their reactivity modes for achieving mild and robust synthesis of nitro compounds. Our group has a longstanding interest in developing cost-effective, readily available, recyclable nitrating reagents derived from organic scaffolds. These reagents serve as a controllable source of nitryl radical and nitronium ion species, enabling mild and practical nitration of hydrocarbons with exceptional functional group tolerance. This account details the development of nitrating reagents and their diverse applications in catalytic nitration across various classes of organic molecules.

Morphology governs function. Yet, understanding and controlling the emergence of morphology at the molecular level remains challenging. The difficulty in studying the early stage of morphology formation is due to its stochastic nature both spatially and temporally occurring at the nanoscale. This nature has been particularly detrimental for the application of optical spectroscopy. To overcome this problem, we have been developing new in situ/in vivo optical spectroscopy tools, which are label-free and non-invasive. This account highlights several examples of how optical spectroscopy can become an important tool in studying the birth of morphology.

All three natural polymers of biomass and the monomer platforms derived from them present multiple avenues to develop products from specialty to bulk markets, which could serve as entry points into the industry for bio based sustainable materials. However, several roadblocks still exist in the pathway of technology development of these materials due to challenges related to cost-competitiveness, scalability, performance and sustainability. This review outlines these major technical challenges as four key checkpoints (cost-competitive, scalability, sustainability, performance) to be addressed for successful market entry of a new sustainable material.