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Substrate Profile (substrate + profile)

Distribution by Scientific Domains
Chemistry75%

Selected Abstracts

ChemInform Abstract: Development of Highly Enantioselective New Lewis Basic N-Formamide Organocatalysts for Hydrosilylation of Imines with an Unprecedented Substrate Profile.

CHEMINFORM, Issue 16 2009
Pengcheng Wu
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Identification of potential substrate proteins for the periplasmic Escherichia coli chaperone Skp

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 23-24 2008
Svenja Jarchow
Abstract The "seventeen kilodalton protein" (Skp) is a predominant periplasmic chaperone of Escherichia coli, which is involved in the biogenesis of abundant outer membrane proteins (OMPs) such as OmpA, PhoE, and LamB. In this study the substrate profile of Skp was investigated in a proteomics approach. Skp was overexpressed in a deficient E. coli strain as a fusion protein with the Strep,tag and captured, together with any host proteins associated with it, from the periplasmic cell extract under mild conditions via one-step Strep,Tactin affinity chromatography. Copurified substrate proteins were then identified by high resolution 2-DE with immobilized pH-gradients, followed by MALDI-TOF MS. Apart from the known Skp substrates, including OmpA and LamB, more than 30 other interacting proteins were detected, especially from the outer membrane, among these FadL and BtuB, and from the periplasm such as MalE and OppA. Thus, Skp does not only serve as a specialized chaperone for a small set of OMPs, but it seems to exhibit a broader substrate spectrum, including soluble periplasmic proteins. These findings should prompt further investigation into the physiological role of Skp and may promote its use for the bacterial production of biochemically active heterologous proteins whose folding requires secretion into the oxidizing milieu of the periplasm. [source]

Organic anion transporters: discovery, pharmacology, regulation and roles in pathophysiology

BIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 1 2010
Adam L. VanWert
Abstract Our understanding of the mechanisms behind inter- and intra-patient variability in drug response is inadequate. Advances in the cytochrome P450 drug metabolizing enzyme field have been remarkable, but those in the drug transporter field have trailed behind. Currently, however, interest in carrier-mediated disposition of pharmacotherapeutics is on a substantial uprise. This is exemplified by the 2006 FDA guidance statement directed to the pharmaceutical industry. The guidance recommended that industry ascertain whether novel drug entities interact with transporters. This suggestion likely stems from the observation that several novel cloned transporters contribute significantly to the disposition of various approved drugs. Many drugs bear anionic functional groups, and thus interact with organic anion transporters (OATs). Collectively, these transporters are nearly ubiquitously expressed in barrier epithelia. Moreover, several reports indicate that OATs are subject to diverse forms of regulation, much like drug metabolizing enzymes and receptors. Thus, critical to furthering our understanding of patient- and condition-specific responses to pharmacotherapy is the complete characterization of OAT interactions with drugs and regulatory factors. This review provides the reader with a comprehensive account of the function and substrate profile of cloned OATs. In addition, a major focus of this review is on the regulation of OATs including the impact of transcriptional and epigenetic factors, phosphorylation, hormones and gender. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Preliminary crystallographic studies of glucose dehydrogenase from the promiscuous Entner,Doudoroff pathway in the hyperthermophilic archaeon Sulfolobus solfataricus

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2005
Alex Theodossis
The hyperthermophilic archaeon Sulfolobus solfataricus grows optimally above 353,K and can metabolize glucose and its C4 epimer galactose via a non-phosphorylative variant of the Entner,Doudoroff pathway involving catalytically promiscuous enzymes that can operate with both sugars. The initial oxidation step is catalysed by glucose dehydrogenase (SsGDH), which can utilize both NAD and NADP as cofactors. The enzyme operates with glucose and galactose at similar catalytic efficiency, while its substrate profile also includes a range of other five- and six-carbon sugars. Crystals of the 164,kDa SsGDH homotetramer have been grown under a variety of conditions. The best crystals to date diffract to 1.8,Å on a synchrotron source, have orthorhombic symmetry and belong to space group P21212. Attempts are being made to solve the structure by MAD and MR. [source]