The Carbohydrate Esterase family 4 contains virulence factors which modify peptidoglycan and biofilm-related exopolysaccharides. Despite the importance of this family of enzymes, a potent mechanism-based inhibition strategy has yet to emerge. Based on the postulated tridentate binding mode of th...

HypothesisThe interaction of lysozyme with the N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG) unit of peptidoglycan (PGN) polymer of the bacterial cell wall is of immense importance to understand the mechanism of lysozyme on PGN.

The senescence-associated β-galactosidase (SA-βG) assay is one of the few accepted markers of cell aging. However, the cytochemical method using 5-bromo-4-chloro-3-indolyl β-d-galactopyranoside (X-Gal) as substrate is limited in sensitivity and is only semiquantitative. Here, we modified the ...

A convenient and efficient synthesis of new 5-azapurine derivatives was developed. The regioisomeric 5-amino-6,7-dihydro- and 7-amino-4,5-dihydro[1,2,4]triazolo[1,5-a][1,3,5]triazines were prepared in 3–4 steps from benzhydrazide via complementary and regiospecific routes as a part of our lead ...

The cyclocondensation reactions between l-α-amino acid phenylhydrazides and 2,3-O-isopropylidene-l-erythruronolactone in the presence of a catalytic amount of p-toluenesulfonic acid afforded diastereomerically pure (3S,6R,7R,7aS)-3-substituted-6,7-isopropylidenedioxy-1-phenylamino-dihydro-1H-py...

To identify an orally active corticotropin-releasing factor 1 receptor antagonist, a series of 6,7-dihydro-5H-cyclopenta[d]pyrazolo[1,5-a]pyrimidines and their derivatives were designed, synthesized and evaluated. An in vitro study followed by in vivo and pharmacokinetic studies of these heterot...

A sensitive, selective, and reliable LC-MS/MS method was developed and validated for simultaneous quantification of venlafaxine (VEN) and its 5 metabolites (ODV, NDV, NNDDV, OHV and NODDV) in rat plasma. The calibration ranges are 15.0 to 6000 ng/mL for VEN, 1.00 to 400 ng/mL for ODV, 5.00 to 20...

Antidepressant drugs such as Venlafaxine (VFX) and O-desmethylvenlafaxine (ODMVFX) are emerging contaminants that are commonly detected in aquatic environments, since conventional wastewater treatment plants are unable to completely remove them. They can be precursors of hazardous by-products, s...

The stereoselectivity of R,S-venlafaxine and its metabolites R,S-O-desmethylvenlafaxine, N-desmethylvenlafaxine, O,N-didesmethylvenlafaxine, N,N-didesmethylvenlafaxine and tridesmethylvenlafaxine was studied in three processes: (i) anaerobic and aerobic laboratory scale tests; (ii) six wastewate...

The complete three-dimensional structure of the α-amylase inhibitor Tendamistat in aqueous solution was determined by 1H nuclear magnetic resonance and distance geometry calculations using the program DISMAN. Compared to an earlier, preliminary determination of the polypeptide backbone conforma...

The three-dimensional structure of the α-amylase inhibitor Tendamistat determined by nuclear magnetic resonance in aqueous solution is compared with the Tendamistat crystal structure refined at 2·0 Å resolution. Between the two independently obtained structures the root-mean-square distances a...

This is a preliminary report on the determination of the solution conformation of the α-amylase inhibitor Tendamistat by nuclear magnetic resonance and distance geometry calculations. A characterization is given of the complete polypeptide backbone fold and the side-chains of the presumed activ...

The 1H nuclear magnetic resonance (n.m.r.) spectrum of the α-amylase inhibitor Tendamistat was completely assigned with the use of phase-sensitive homonuclear twodimensional n.m.r. The assignments include the non-labile protons of the 74 amino acid residues as well as the labile protons which e...

A penalty function is introduced into molecular dynamics simulations that improves on current methods for enforcing nuclear magnetic resonance-based distance restraints. Rather than treating nuclear Overhauser effects as static distance bounds, they are considered as quantities that must be sati...

Unfolding of the small α-amylase inhibitor tendamistat (74 residues, 2 disulfide bridges) has been characterized thermodynamically by high sensitivity scanning microcalorimetry. To link the stability parameters with structural information we use heat capacity group parameters and water accessib...

In this study the pH dependence of the thermodynamic stability of tendamistat is analyzed. This small globular protein of 74 residues shows a very marked dependence of thermal stability on pH: the denaturation temperature increases from 68.9°C at pH 2.0 to 93.2°C at pH 5.0, and then decreases ...

Tendamistat, a small disulfide-bonded β-sheet protein, and its three single/double-disulfide mutants are investigated by using a modified Gō-like model, aiming to understand the folding mechanism of disulfide-bonded protein as well as the effects of removal of disulfide bond on the folding pro...

Parvulustat is a small, highly active proteinaceous α-amylase inhibitor whose high-resolution NMR structure was recently solved in Frankfurt. Here, we present its biochemical and biophysical characterization. Several spectroscopic methods such as UV, fluorescence and CD were utilized to extract...

Squalene synthetase of pig liver has been solubilized and partially purified. This enzyme has a pH optimum of 7.4 and a Km value of 5 × 10−7M for farnesyl pyrophosphate. A divalent metal ion, Mg++ or Mn++, and NADPH are required for the conversion of farnesyl pyrophosphate to squalene. Inhibiti...

This review chronicles the strategies and hurdles encountered in farnesyl transferase inhibitor drug discovery programs, with the major focus on substrate-based inhibitor design. Recently reported enzyme structure studies and their potential impact on drug design are also discussed. The anti-pro...