https://www.selleckchem.com/products/disodium-r-2-hydroxyglutarate.html Ribonucleotideprotein interactions play crucial roles in a number of biological processes. Unlike the RNAprotein interface where van der Waals contacts are prevalent, the recognition of a single ribonucleotide such as ATP by a protein occurs predominantly through hydrogen-bonding interactions. As a first step toward understanding the role of hydrogen bonding in ribonucleotideprotein recognition, the present work employs density functional theory to provide a detailed quantum-mechanical analysis of the structural and energetic characteristics of 18 unique hydrogen-bonded pairs involving the nucleobase/nucleoside moiety of four canonical ribonucleotides and the side chains of three polar amino-acid residues (arginine, glutamine, and glutamic acid) of proteins. In addition, we model five new pairs that are till now not observed in crystallographically identified ribonucleotideprotein complexes but may be identified in complexes crystallized in the future. We critically examine the characteristics of each pair inunconventional "amino-acceptor" hydrogen bonding with comparable (-9.4 kcal mol-1) strength to the corresponding conventional (i.e., aminodonor) structure (-9.2 kcal mol-1). This points to the importance of amino-acceptor hydrogen bonds in RNAprotein interactions and suggests that such interactions must be considered in the future while studying the dynamics in the context of molecular recognition. Overall, our study provides preliminary insights into the intrinsic features of ribonucleotideamino acid interactions, which may help frame a clearer picture of the molecular basis of RNAprotein recognition and further appreciate the role of such contacts in biology. Copyright © 2020 American Chemical Society.Bedaquiline (BDQ) is the most critical pharmaceutical in the world for treating multidrug-resistant Mycobacterium tuberculosis. Despite it being highly effective, BDQ asymmetric synthesis rem