Carbon-Carbon Double Bond Isomerases: Enzymes that catalyze the shifting of a carbon-carbon double bond from one position to another within the same molecule. EC 5.3.3.Alkenes: Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)Sulfur-Sulfur Bond Isomerases: Enzymes that catalyze the transposition of a sulfur-sulfur bond. EC 5.3.4.Aldose-Ketose Isomerases: Enzymes that catalyze the interconversion of aldose and ketose compounds.Isomerases: A class of enzymes that catalyze geometric or structural changes within a molecule to form a single product. The reactions do not involve a net change in the concentrations of compounds other than the substrate and the product.(from Dorland, 28th ed) EC 5.Organic Chemistry Processes: The reactions, changes in structure and composition, the properties of the reactions of carbon compounds, and the associated energy changes.Carbon-Carbon Lyases: Enzymes that catalyze the cleavage of a carbon-carbon bond by means other than hydrolysis or oxidation. This subclass contains the DECARBOXYLASES, the ALDEHYDE-LYASES, and the OXO-ACID-LYASES. EC 4.1.Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.Peptidylprolyl Isomerase: An enzyme that catalyzes the isomerization of proline residues within proteins. EC 126.96.36.199.Amino Acid Isomerases: Enzymes that catalyze either the racemization or epimerization of chiral centers within amino acids or derivatives. EC 5.1.1.Palladium: A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)KetonesCyclization: Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Carbohydrate Epimerases: Enzymes that catalyze the epimerization of chiral centers within carbohydrates or their derivatives. EC 5.1.3.Chemistry Techniques, Synthetic: Methods used for the chemical synthesis of compounds. Included under this heading are laboratory methods used to synthesize a variety of chemicals and drugs.Protein Disulfide-Isomerases: Sulfur-sulfur bond isomerases that catalyze the rearrangement of disulfide bonds within proteins during folding. Specific protein disulfide-isomerase isoenzymes also occur as subunits of PROCOLLAGEN-PROLINE DIOXYGENASE.Phosphines: Inorganic or organic compounds derived from phosphine (PH3) by the replacement of H atoms. (From Grant & Hackh's Chemical Dictionary, 5th ed)Steroid Isomerases: Enzymes that catalyze the transposition of double bond(s) in a steroid molecule. EC 5.3.3.Chemistry, Organic: The study of the structure, preparation, properties, and reactions of carbon compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Sulfur Compounds: Inorganic or organic compounds that contain sulfur as an integral part of the molecule.Cyclophilins: A family of peptidyl-prolyl cis-trans isomerases that bind to CYCLOSPORINS and regulate the IMMUNE SYSTEM. EC 5.2.1.-Boron: A trace element with the atomic symbol B, atomic number 5, and atomic weight [10.806; 10.821]. Boron-10, an isotope of boron, is used as a neutron absorber in BORON NEUTRON CAPTURE THERAPY.Alkadienes: Acyclic branched or unbranched hydrocarbons having two carbon-carbon double bonds.Dodecenoyl-CoA Isomerase: A carbon-carbon double bond isomerase that catalyzes the movement double bond from C3 to C2 of an unsaturated acyl-CoA. The enzyme plays a key role in allowing acyl-CoA substrates to re-enter the beta-oxidation pathway.