Asymmetric hydrophosphinylation of 1,3-dienes with phosphine oxides using an inexpensive chiral catalyst has been demonstrated, providing access to chiral allylic phosphine oxides with broad substrate scope and high regio- and enantioselectivity.
Snake venoms represent a danger to human health, but also a gold mine of bioactive proteins that can be harnessed for drug discovery purposes. The evolution of snakes and their venom has been studied for decades, particularly via traditional morphological and basic genetic methods alongside venom proteomics. However, while the field of genomics has matured rapidly over the past 2 decades, owing to the development of next-generation sequencing technologies, snake genomics remains in its infancy. Here, we provide an overview of the state of the art in snake genomics and discuss its potential implications for studying venom evolution and toxinology. On the basis of current knowledge, gene duplication and positive selection are key mechanisms in the neofunctionalization of snake venom proteins. This makes snake venoms important evolutionary drivers that explain the remarkable venom diversification and adaptive variation observed in these reptiles. Gene duplication and neofunctionalization have also generated a large number of repeat sequences in snake genomes that pose a significant challenge to DNA sequencing, resulting in the need for substantial computational resources and longer sequencing read length for high-quality genome assembly. Fortunately, owing to constantly improving sequencing technologies and computational tools, we are now able to explore the molecular mechanisms of snake venom evolution in unprecedented detail. Such novel insights have the potential to affect the design and development of antivenoms and possibly other drugs, as well as provide new fundamental knowledge on snake biology and evolution.
In this article, we report a general protocol for the direct decarboxylative chlorination, iodination, and bromination of aliphatic carboxylic acids catalyzed by iron salts under visible light. This method enjoys a broad substrate scope with good functional group compatibility, including complex natural products. Benzylic and allylic C(sp3)–H bonds can be retained under the oxidative halogenation conditions. This method also shows application potential for late-stage functionalization.
For the inactivation or removal of bacterial biofilms via chemical or physical processes, it is crucial to sufficiently wet the biofilm surface. However, many bacterial biofilms efficiently resist wetting by water, oil or even organic solvents. Here, we demonstrate how exposing the surface of mature biofilm colonies to concentrated ethanol, saline or glucose solutions results in topographical changes that enable their wettability. With this approach, even omniphobic biofilm colonies become wettable towards aqueous solutions and oils. As a result of this reduced liquid repellency, the biofilms become susceptible to erosion by water which allows for their removal from the substrate they have been grown on. Moreover, bacteria within pre-treated biofilms can now be inactivated with antibiotic solutions. Thus, the biofilm treatment strategy presented here presents a new stepping stone for fighting biofilms in either industrial or medical settings.