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The asymmetric dehydration of alcohols is an important process for the direct synthesis of alkenes. We report the structure and substrate specificity of the bifunctional linalool dehydratase isomerase (LinD) from the bacterium Castellaniella defragrans that catalyzes in nature the hydration of β-myrcene to linalool and the subsequent isomerization to geraniol. Enzymatic kinetic resolutions of truncated and elongated aromatic and aliphatic tertiary alcohols (C5-C15) that contain a specific signature motif demonstrate the broad substrate specificity of LinD. The three-dimensional structure of LinD from Castellaniella defragrans revealed a pentamer with active sites at the protomer interfaces. Furthermore, the structure of LinD in complex with the product geraniol provides initial mechanistic insights into this bifunctional enzyme. Site-directed mutagenesis confirmed active site amino acid residues essential for its dehydration and isomerization activity. These structural and mechanistic insights facilitate the development of hydrating catalysts, enriching the toolbox for novel bond-forming biocatalysis.

The rapid scientific and technological merging between Internet of Things (IoT), cloud computing and wireless body area networks (WBANs) have significantly contributed to the advent of e-healthcare. Due to this the quality of medicinal care has also been improved. Specifically, patient-centric health care monitoring plays important role in e-healthcare facilities by providing important assistance in different areas, including medical data collection and aggregation, data transmission, data processing, data query, and so on. This paper proposed an architectural framework to describe complete monitoring life cycle and indicates the important service modules. More meticulous discussions are then devoted to data gathering at patient side, which definitely serves as essential basis in achieving efficient, vigorous and protected patient health monitoring. Different design challenges are also analyzed to develop a high quality and protected patient-centric monitoring systems along with their possible potential solutions.

A blood glucose level lowering effect is postulated for polyphenols (PPs), which is in part attributed to the inhibition of α-amylase. To estimate structure−effect relationships, chlorogenic acid (CA), phlorizin (PHL), epigallocatechin gallate (EGCG), epicatechin (EC), and malvidin-3-glucoside (Mlv-3-glc) were used as inhibitors in an enzyme assay, on the basis of the conversion of GalG 2 CNP by α-amylase. The detection of CNP was performed by UV/vis spectroscopy. The data reveal that the inhibitor strength decreases as follows: EGCG > Mlv-3-glc > EC > PHL ∼ CA. Detection of the substrate conversion by isothermal titration calorimetry supports these results. All PPs showed mixed inhibition, except for CA and EGCG wherein the competitive proportion was predominant. Investigations by saturation transfer difference NMR revealed interaction of PPs with α-amylase prevalently based on interactions with the aromatic or conjugated system. A correlation between the extent of the conjugated system and the IC 50 of the PP could be found.