Biomaterial Database

Selenium protection against mercury toxicity: high binding affinity of methylmercury by selenium-containing ligands in comparison with sulfur-containing ligands. 1978

Y Sugiura, and Y Tamai, and H Tanaka

In determining the protection of selenium against mercury toxicity, the binding affinity of methylmercury by various selenium-containing ligands was investigated by proton magnetic resonance (PMR) spectroscopy. The most striking feature was the small J199Hg-1H value of the selenocysteamine- and selenocysteine-methylmercury complexes, namely, the high affinity of the selenohydryl group to the mercury in comparison with those of the sulfhydryl and amino groups. The order of binding affinity of the coordination groups toward methylmercury is clearly SeH greater than SH greater than or equal to Se-Se greater than NH2 greater than S-S, SeCH3, SCH3. A definite correlation was found to exist between the mercury-proton coupling constants and the chemical shifts of methyl groups of the methylmercury complexes. A relationship between the order (Se greater than S greater than NH2) of affinity for methylmercury and the basicity (or electronegativity and covalent radius) of the donor groups was also discussed. These results suggest the high covalency of the CH3Hg-Se bond, which involves dpi-dpi back bonding.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008024	Ligands	A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)	Ligand
D008767	Methylmercury Compounds	Organic compounds in which mercury is attached to a methyl group.	Methyl Mercury Compounds,Compounds, Methyl Mercury,Compounds, Methylmercury,Mercury Compounds, Methyl
D009682	Magnetic Resonance Spectroscopy	Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).	In Vivo NMR Spectroscopy,MR Spectroscopy,Magnetic Resonance,NMR Spectroscopy,NMR Spectroscopy, In Vivo,Nuclear Magnetic Resonance,Spectroscopy, Magnetic Resonance,Spectroscopy, NMR,Spectroscopy, Nuclear Magnetic Resonance,Magnetic Resonance Spectroscopies,Magnetic Resonance, Nuclear,NMR Spectroscopies,Resonance Spectroscopy, Magnetic,Resonance, Magnetic,Resonance, Nuclear Magnetic,Spectroscopies, NMR,Spectroscopy, MR
D002621	Chemistry	A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
D003543	Cysteamine	A mercaptoethylamine compound that is endogenously derived from the COENZYME A degradative pathway. The fact that cysteamine is readily transported into LYSOSOMES where it reacts with CYSTINE to form cysteine-cysteamine disulfide and CYSTEINE has led to its use in CYSTINE DEPLETING AGENTS for the treatment of CYSTINOSIS.	Cysteinamine,Mercaptamine,2-Aminoethanethiol,Becaptan,Cystagon,Cysteamine Bitartrate,Cysteamine Dihydrochloride,Cysteamine Hydrobromide,Cysteamine Hydrochloride,Cysteamine Maleate (1:1),Cysteamine Tartrate,Cysteamine Tartrate (1:1),Cysteamine Tosylate,Cysteamine, 35S-Labeled,Mercamine,Mercaptoethylamine,beta-Mercaptoethylamine,2 Aminoethanethiol,35S-Labeled Cysteamine,Bitartrate, Cysteamine,Cysteamine, 35S Labeled,Dihydrochloride, Cysteamine,Hydrobromide, Cysteamine,Hydrochloride, Cysteamine,Tartrate, Cysteamine,Tosylate, Cysteamine,beta Mercaptoethylamine
D012643	Selenium	An element with the atomic symbol Se, atomic number 34, and atomic weight 78.97. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.	Selenium-80,Selenium 80
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D013455	Sulfur	An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine.	Sulfur-16,Sulfur 16
D055598	Chemical Phenomena	The composition, structure, conformation, and properties of atoms and molecules, and their reaction and interaction processes.	Chemical Concepts,Chemical Processes,Physical Chemistry Concepts,Physical Chemistry Processes,Physicochemical Concepts,Physicochemical Phenomena,Physicochemical Processes,Chemical Phenomenon,Chemical Process,Physical Chemistry Phenomena,Physical Chemistry Process,Physicochemical Phenomenon,Physicochemical Process,Chemical Concept,Chemistry Process, Physical,Chemistry Processes, Physical,Concept, Chemical,Concept, Physical Chemistry,Concept, Physicochemical,Concepts, Chemical,Concepts, Physical Chemistry,Concepts, Physicochemical,Phenomena, Chemical,Phenomena, Physical Chemistry,Phenomena, Physicochemical,Phenomenon, Chemical,Phenomenon, Physicochemical,Physical Chemistry Concept,Physicochemical Concept,Process, Chemical,Process, Physical Chemistry,Process, Physicochemical,Processes, Chemical,Processes, Physical Chemistry,Processes, Physicochemical