Biomaterial Database

Leucine enkephalin-tyrosinase reaction products--identification and biological activity. 1994

V Larsimont, and L Prokai, and G Hochhaus

Department of Pharmaceutics, University of Florida, JHMHC, Gainesville 32610.

Leucine enkephalin (1 mM) was reacted with mushroom tyrosinase under reductive conditions (ascorbic acid, 50 mM). Reaction products were isolated by high-performance liquid chromatography and identified using electrospray ionization mass spectrometry. The products of the reaction were found to be hydroxylated at the Tyr1 moiety of the peptide. The major product was a monohydroxylated derivative of leucine enkephalin ([HO-Tyr1]LE) and the minor product of the reaction was a dihydroxylated derivative ([(HO)2-Tyr1]LE). The affinity of [HO-Tyr1]LE to receptors in rat brain homogenate was compared to that of leucine enkephalin itself. Hydroxylation of LE was found to decrease receptor affinity to both mu and delta opioid receptor sites by a factor of about 20.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D011957	Receptors, Opioid	Cell membrane proteins that bind opioids and trigger intracellular changes which influence the behavior of cells. The endogenous ligands for opioid receptors in mammals include three families of peptides, the enkephalins, endorphins, and dynorphins. The receptor classes include mu, delta, and kappa receptors. Sigma receptors bind several psychoactive substances, including certain opioids, but their endogenous ligands are not known.	Endorphin Receptors,Enkephalin Receptors,Narcotic Receptors,Opioid Receptors,Receptors, Endorphin,Receptors, Enkephalin,Receptors, Narcotic,Receptors, Opiate,Endorphin Receptor,Enkephalin Receptor,Normorphine Receptors,Opiate Receptor,Opiate Receptors,Opioid Receptor,Receptors, Normorphine,Receptors, beta-Endorphin,beta-Endorphin Receptor,Receptor, Endorphin,Receptor, Enkephalin,Receptor, Opiate,Receptor, Opioid,Receptor, beta-Endorphin,Receptors, beta Endorphin,beta Endorphin Receptor,beta-Endorphin Receptors
D001923	Brain Chemistry	Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.	Chemistry, Brain,Brain Chemistries,Chemistries, Brain
D002845	Chromatography	Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.	Chromatographies
D004743	Enkephalin, Leucine	One of the endogenous pentapeptides with morphine-like activity. It differs from MET-ENKEPHALIN in the LEUCINE at position 5. Its first four amino acid sequence is identical to the tetrapeptide sequence at the N-terminal of BETA-ENDORPHIN.	Leucine Enkephalin,5-Leucine Enkephalin,Leu(5)-Enkephalin,Leu-Enkephalin,5 Leucine Enkephalin,Enkephalin, 5-Leucine,Leu Enkephalin
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013058	Mass Spectrometry	An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.	Mass Spectroscopy,Spectrometry, Mass,Spectroscopy, Mass,Spectrum Analysis, Mass,Analysis, Mass Spectrum,Mass Spectrum Analysis,Analyses, Mass Spectrum,Mass Spectrum Analyses,Spectrum Analyses, Mass
D014443	Tyrosine	A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.	L-Tyrosine,Tyrosine, L-isomer,para-Tyrosine,L Tyrosine,Tyrosine, L isomer,para Tyrosine