The perturbational treatment of H-bonded systems reduces the discussion of H-bond properties to that of proton donor and proton acceptor properties. Among the variety of interaction contributions within perturbation theory it is simply the electrostatic interaction which mainly seems to control H-bond strength and stereochemistry of H-bonds. The easy accessible classical and clear electrostatic...

Fluorescence resonance energy transfer (FRET) is an extremely effective tool to detect molecular interaction at suboptical resolutions. One of the techniques for measuring FRET is acceptor photobleaching: the increase in donor fluorescence after complete acceptor photobleaching is a measure of the FRET efficiency. However, in wide-field microscopy, complete acceptor photobleaching is difficult ...

vibrational spectrum has recently been questioned.22 The vibrational frequencies of 3BI and 'B, dimethylsilylene are listed in Table V. One interesting feature of these is the intensity pattern for the two modes occurring near 1400 cm-' which, by analogy with 'Al, should be observed experimentally near 1200 cm-'. In 'Al these were both observable with moderate to strong intensity; for 3Bl they ...

Alkyl branching at the β position of a polyketide intermediate is an important variation on canonical polyketide natural product biosynthesis. The branching enzyme, 3-hydroxy-3-methylglutaryl synthase (HMGS), catalyzes the aldol addition of an acyl donor to a β-keto-polyketide intermediate acceptor. HMGS is highly selective for two specialized acyl carrier proteins (ACPs) that deliver the donor...

Density functional theory calculations were used to systematically explore the effects of axial ligation by solvent molecules on reactivity and selectivity dirhodium tetracarboxylates with diazo compounds in context C–H insertion into propane. Insertions three types compounds?acceptor/acceptor, donor/acceptor, donor/donor?promoted tetraformate tested without for no surrounding solvent, dichloro...

Sialyltransferases are enzymes responsible for the important sialylation of glycoconjugates. Since crystal structures are not available, other tools are needed to study enzymatic mechanisms. As a model, we used human alpha2,6-sialyltransferase. A putative acceptor-binding domain containing the small and the very small sialyl motifs was randomly mutated. This resulted in enzymes with altered enz...

This study focuses on RR, SS and RS medetomidine (MM) and inclusion of several achiral acids to distinguish which acid can help conglomerate formation instead of crystallizating racemic mixtures by defining the low-lying energy of their structures. Favorable orientation of acids was determined in interaction with the MM enantiomers after optimization. The most noticeable interactions include hy...

Förster resonance energy transfer (FRET) interacted with localized surface plasmon (LSP) gives us the ability to overcome inadequate transfer of energy between donor and acceptor nanocrystals (NCs). In this paper, we show LSP-enhanced FRET in colloidal photosensors of NCs in operation, resulting in substantially enhanced photosensitivity. The proposed photosensitive device is a layered self-ass...