The stereoselective sulfate conjugation of 4'-methoxyfenoterol stereoisomers by sulfotransferase enzymes

The enantioselective metabolic mechanism of quizalofop-ethyl and quizalofop-acid enantiomers in animal: protein binding, intestinal absorption, and in vitro metabolism in plasma and the microsome

The effects of protein binding (pepsin, trypsin and serum albumin), intestinal absorption (everted gut sac), and degradation (plasma, liver microsome and cytosol) on the enantioselectivity of quizalofop-ethyl in animals were studiedin vitro.

In Silico Prediction of Human Sulfotransferase 1E1 Activity Guided by Pharmacophores from Molecular Dynamics Simulations

Acting during phase II metabolism, sulfotransferases (SULTs) serve detoxification by transforming a broad spectrum of compounds from pharmaceutical, nutritional, or environmental sources into more easily excretable metabolites. However, SULT activity has also been shown to promote formation of reactive metabolites that may have genotoxic effects. SULT subtype 1E1 (SULT1E1) was identified as a key player in estrogen homeostasis, which is involved in many physiological processes and the pathogenesis of breast and endometrial cancer. The development of an in silico prediction model for SULT1E1 ligands would therefore support the development of metabolically inert drugs and help to assess health risks related to hormonal imbalances. Here, we report on a novel approach to develop a model that enables prediction of substrates and inhibitors of SULT1E1. Molecular dynamics simulations were performed to investigate enzyme flexibility and sample protein conformations. Pharmacophores were developed that served as a cornerstone of the model, and machine learning techniques were applied for prediction refinement. The prediction model was used to screen the DrugBank (a database of experimental and approved drugs): 28% of the predicted hits were reported in literature as ligands of SULT1E1. From the remaining hits, a selection of nine molecules was subjected to biochemical assay validation and experimental results were in accordance with the in silico prediction of SULT1E1 inhibitors and substrates, thus affirming our prediction hypotheses.

Reprint of: fRMSDchiral: a novel algorithm to represent differences between positions of stereoisomers in complex with dissymmetric binding site

The ability of molecules to distinguish between optical isomers is crucial for living systems. The change of position of one enantiomer in respect to the position of the second enantiomer within an asymmetric binding site may be analyzed on different levels. Root Mean Square Deviation (RMSD) may be used for such analyses with low precision. Additional fragment level variants of RMSD allow for more precise definition of differences in location of the main molecular features responsible for recognition of stereoisomers by a selector. Three fRMSDchiral parameters appear to be very useful to precisely quantify the change in orientations of stereoisomers. Proposed calculation emerges as interesting assistance in interpretation of consequences of formation differential interaction(s) responsible for a chiral recognition process.

fRMSDchiral: a novel algorithm to represent differences between positions of stereoisomers in complex with dissymmetric binding site

The ability of molecules to distinguish between optical isomers is crucial for living systems. The change of position of one enantiomer in respect to the position of the second enantiomer within an asymmetric binding site may be analyzed on different levels. Root Mean Square Deviation (RMSD) may be used for such analyses with low precision. Additional fragment level variants of RMSD allow for more precise definition of differences in location of the main molecular features responsible for recognition of stereoisomers by a selector. Three fRMSDchiral parameters appear to be very useful to precisely quantify the change in orientations of stereoisomers. Proposed calculation emerges as interesting assistance in interpretation of consequences of formation differential interaction(s) responsible for a chiral recognition process.