Metal complexes of macrocyclic ligands mimicking enzyme activity

LUBAL, Přemysl, Antonín ŠTĚPÁNEK and Zdeňka JAROLÍMOVÁ. Metal complexes of macrocyclic ligands mimicking enzyme activity. In Abstract Book of ISABC 10 conference (International Symposium on Applied Bioinorganic Chemistry). Debrecen: Department of Inorganic and Analytical Chemistry, Debrecen University, 2009, 224 pp. ISBN 978-963-473-307-2.

Basic information

• Original name: Metal complexes of macrocyclic ligands mimicking enzyme activity
• Name in Czech: Kovové komplexy macrocyklických ligandů jako modely enzymů
• Authors: LUBAL, Přemysl (203 Czech Republic, guarantor, belonging to the institution), Antonín ŠTĚPÁNEK (203 Czech Republic, belonging to the institution) and Zdeňka JAROLÍMOVÁ (203 Czech Republic, belonging to the institution).
• Edition: Debrecen, Abstract Book of ISABC 10 conference (International Symposium on Applied Bioinorganic Chemistry), 224 pp. 2009.
• Publisher: Department of Inorganic and Analytical Chemistry, Debrecen University

Other information

• Original language: English
• Type of outcome: Proceedings paper
• Field of Study: 10406 Analytical chemistry
• Country of publisher: Hungary
• Confidentiality degree: is not subject to a state or trade secret
• RIV identification code: RIV/00216224:14310/09:00037452
• Organization unit: Faculty of Science
• ISBN: 978-963-473-307-2
• Keywords in English: macrocyclic ligands; metal complexes; enzyme; analytical determination; nucleotides
• Tags: International impact

Abstract

Metal ions form with macrocyclic ligands more stable complexes than with analogous acyclic ligands from both thermodynamic and kinetic point of view. These complexes can be studied as suitable models in order to mimic the metaloenzyme activity. In this contribution, the catalytic activity of [M(cyclen)]2+ complexes (M = Zn, Cd, Cu, Ni, cyclen = 1,4,7,10-tetraazacyclodecane, [12]aneN4) which are mimicking enzymes was investigated for hydrolysis of acetic acid esters acting as substrate. The rate of ester hydrolysis was monitored by molecular absorption (for 4-nitrophenylacetate) or luminescence (for 4-methylumbelliferylacetate) spectroscopy and optimal experimental conditions (e.g. temperature, pH, buffer, etc.) were found. The catalytic activity of the most active Zn(II) and Cd(II) metal complexes is inhibited by some compounds due to formation of stable ternary complexes. The influence of various inhibiting agents (mostly base, e.g. Thymin, Uracil, Cytosin, Adenin, Guanin, and their simple nucleosides and nucleotides) on rate of ester hydrolysis was studied. The effect of minute structural changes of inhibitors is the highest for nucleotides and the smallest for bases. The inhibition constants were evaluated from experimental data and compared with analogous systems. Metal ions form with macrocyclic ligands more stable complexes than with analogous acyclic ligands from both thermodynamic and kinetic point of view. These complexes can be studied as suitable models in order to mimic the metaloenzyme activity. In this contribution, the catalytic activity of [M(cyclen)]2+ complexes (M = Zn, Cd, Cu, Ni, cyclen = 1,4,7,10-tetraazacyclodecane, [12]aneN4) which are mimicking enzymes was investigated for hydrolysis of acetic acid esters acting as substrate. The rate of ester hydrolysis was monitored by molecular absorption (for 4-nitrophenylacetate) or luminescence (for 4-methylumbelliferylacetate) spectroscopy and optimal experimental conditions (e.g. temperature, pH, buffer, etc.) were found. The catalytic activity of the most active Zn(II) and Cd(II) metal complexes is inhibited by some compounds due to formation of stable ternary complexes. The influence of various inhibiting agents (mostly base, e.g. Thymin, Uracil, Cytosin, Adenin, Guanin, and their simple nucleosides and nucleotides) on rate of ester hydrolysis was studied. The effect of minute structural changes of inhibitors is the highest for nucleotides and the smallest for bases. The inhibition constants were evaluated from experimental data and compared with analogous systems.

Abstract (in Czech)

Metal ions form with macrocyclic ligands more stable complexes than with analogous acyclic ligands from both thermodynamic and kinetic point of view. These complexes can be studied as suitable models in order to mimic the metaloenzyme activity. In this contribution, the catalytic activity of [M(cyclen)]2+ complexes (M = Zn, Cd, Cu, Ni, cyclen = 1,4,7,10-tetraazacyclodecane, [12]aneN4) which are mimicking enzymes was investigated for hydrolysis of acetic acid esters acting as substrate. The rate of ester hydrolysis was monitored by molecular absorption (for 4-nitrophenylacetate) or luminescence (for 4-methylumbelliferylacetate) spectroscopy and optimal experimental conditions (e.g. temperature, pH, buffer, etc.) were found. The catalytic activity of the most active Zn(II) and Cd(II) metal complexes is inhibited by some compounds due to formation of stable ternary complexes. The influence of various inhibiting agents (mostly base, e.g. Thymin, Uracil, Cytosin, Adenin, Guanin, and their simple nucleosides and nucleotides) on rate of ester hydrolysis was studied. The effect of minute structural changes of inhibitors is the highest for nucleotides and the smallest for bases. The inhibition constants were evaluated from experimental data and compared with analogous systems. Metal ions form with macrocyclic ligands more stable complexes than with analogous acyclic ligands from both thermodynamic and kinetic point of view. These complexes can be studied as suitable models in order to mimic the metaloenzyme activity. In this contribution, the catalytic activity of [M(cyclen)]2+ complexes (M = Zn, Cd, Cu, Ni, cyclen = 1,4,7,10-tetraazacyclodecane, [12]aneN4) which are mimicking enzymes was investigated for hydrolysis of acetic acid esters acting as substrate. The rate of ester hydrolysis was monitored by molecular absorption (for 4-nitrophenylacetate) or luminescence (for 4-methylumbelliferylacetate) spectroscopy and optimal experimental conditions (e.g. temperature, pH, buffer, etc.) were found. The catalytic activity of the most active Zn(II) and Cd(II) metal complexes is inhibited by some compounds due to formation of stable ternary complexes. The influence of various inhibiting agents (mostly base, e.g. Thymin, Uracil, Cytosin, Adenin, Guanin, and their simple nucleosides and nucleotides) on rate of ester hydrolysis was studied. The effect of minute structural changes of inhibitors is the highest for nucleotides and the smallest for bases. The inhibition constants were evaluated from experimental data and compared with analogous systems.

Links

• LC06035, research and development project: Name: Centrum biofyzikální chemie, bioelektrochemie a bioanalýzy. Nové nástroje pro genomiku, proteomiku a biomedicínu.

Investor: Ministry of Education, Youth and Sports of the CR, Centre of Biophysical Chemistry, Bioelectrochemistry and Bioanalysis. New Tools for Genomics, Proteomics and Biomedicine

• ME09065, research and development project: Name: Výzkum nových detekčních systémů na bázi senzorových polí pro použití ve speciační analýze

Investor: Ministry of Education, Youth and Sports of the CR, Research of new detection systems based on sensor arrays for application in speciation analysis, Research and Development Programme KONTAKT (ME)