Results 111 to 120 of about 821 (130)

Substrate Specificity of Glutaminyl Cyclases from Plants and Animals

Biological Chemistry, 2003
Glutaminyl cyclases (QC) catalyze the intramolecular cyclization of N-terminal glutamine residues of peptides and proteins. For a comparison of the substrate specificity of human and papaya QC enzymes, a novel continuous assay was established by adapting an existing discontinuous method.
Stephan, Schilling, Susanne, Manhart, Torsten, Hoffmann, Hans-Henning, Ludwig, Claus, Wasternack, Hans-Ulrich, Demuth   +5 more
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Glutaminyl Cyclases Display Significant Catalytic Proficiency for Glutamyl Substrates

Biochemistry, 2009
N-Terminal glutaminyl and glutamyl residues of peptides and proteins tend to form pyroglutamic acid (pGlu) by intramolecular cylization. The rate constants for spontaneous cyclization of glutamine (10(-6) s(-1)) and glutamic acid (10(-9) s(-1)) in aqueous solution differ by approximately 3 orders of magnitude at pH 6.5.
Franziska, Seifert, Katrin, Schulz, Birgit, Koch, Susanne, Manhart, Hans-Ulrich, Demuth, Stephan, Schilling   +5 more
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Evidence for Essential Histidines in Human Pituitary Glutaminyl Cyclase

Biochemistry, 2001
Glutaminyl cyclase (QC, EC 2.3.2.5) catalyzes the formation of the pyroglutamyl residue present at the amino terminus of numerous secretory peptides and proteins. Treatment with diethyl pyrocarbonate inactivated recombinant human QC with the apparent modification of three essential histidine residues.
Bateman, Robert C., Temple, Jeffrey S., Misquitta, Stephanie A., Booth, Rachell E.   +3 more
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An Overview of Glutaminyl Cyclase Inhibitors for Alzheimer’s Disease

Future Medicinal Chemistry, 2019
A diverse range of N-terminally truncated and modified forms of amyloid-β (Aβ) oligomers have been discovered in Alzheimer's disease brains, including the pyroglutamate-Aβ (AβpE3). AβpE3 species are shown to be more neurotoxic when compared with the full-length Aβ peptide.
Judite RM Coimbra, Pedro JM Sobral, Armanda E Santos, Paula I Moreira, Jorge AR Salvador   +4 more
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Glutaminyl Cyclase and Its Inhibitors

2022
Human glutaminyl cyclase (hQC), which has two isoforms, is an important enzyme that catalyzes pyroglutamate modification. N-Terminal pyroglutamate (pE) modification is an important post-translational event in mammals. The pE modification catalyzed by QC is a necessary modification for the maturation and function of many proteins and peptides.
KÜÇÜKOĞLU, Kaan, AÇIL, Yasemin Gülbahar   +1 more
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2D- and 3D-QSAR Modeling of Imidazole-Based Glutaminyl Cyclase Inhibitors

Current Computer-Aided Drug Design, 2021
Background: Glutaminyl Cyclase (QC) is a novel target in the battle against Alzheimer’s disease, a highly prevalent neurodegenerative disorder. QC inhibitors have the potential to be developed as therapeutically useful anti-Alzheimer’s disease agents.
Omar Husham Ahmed Al-Attraqchi, Katharigatta N. Venugopala   +1 more
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Inhibition of glutaminyl cyclase alters pyroglutamate formation in mammalian cells

Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics, 2006
Mammalian cell lines were examined concerning their Glutaminyl Cyclase (QC) activity using a HPLC method. The enzyme activity was suppressed by a QC specific inhibitor in all homogenates. Aim of the study was to prove whether inhibition of QC modifies the posttranslational maturation of N-glutamine and N-glutamate peptide substrates.
Holger, Cynis, Stephan, Schilling, Mandy, Bodnár, Torsten, Hoffmann, Ulrich, Heiser, Takaomi C, Saido, Hans-Ulrich, Demuth   +6 more
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Increased Glutaminyl Cyclase Expression in Peripheral Blood of Alzheimer's Disease Patients

Journal of Alzheimer's Disease, 2013
N-truncated and N-modified forms of amyloid-β (Aβ) peptide are found in diffused and dense core plaques in Alzheimer's disease (AD) brain. Among them, the most abundant N-truncated peptide starts with pyroglutamyl at residue 3 (AβpE3). AβpE3 has increased aggregation potential and toxicity and its abundance has been reported to correlate with the ...
VALENTI, Maria Teresa, Bolognin, Silvia, ZANATTA, Cristina, DONATELLI, Luca, INNAMORATI, Giulio, Pampanin M., ZANUSSO, Gianluigi, Zatta P., DALLE CARBONARE, Luca Giuseppe   +8 more
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Glutaminyl cyclase activity is a characteristic feature of human cerebrospinal fluid

Clinica Chimica Acta, 2008
Proteins and peptides occurring in human body fluids can be useful biological markers for neurological diseases and can even contribute to the pathogenesis of such diseases. However, proteins and peptides are potential substrates of proteases and other enzymes.
Anastassia, Gontsarova, Eckhard, Kaufmann, Hayrettin, Tumani, Alexander, Dressel, Friedrich, Mandel, Karl-Heinz, Wiesmüller, Christiane, Kunert-Keil, Heinrich, Brinkmeier   +7 more
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Molecular cloning, sequence analysis and expression of human pituitary glutaminyl cyclase

Journal of Molecular Endocrinology, 1994
A cDNA clone for glutaminyl cyclase was isolated from a human pituitary cDNA library and the complete DNA sequence determined. The cDNA clone had 1573 bp and contained an open reading frame of 1086 bases, coding for a protein of 361 amino acids and molecular mass of 40,876 Da.
Song, I., Chuang, CZ, Bateman, Robert C.
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