Teruo Nakajima

Hypusine, a new amino acid occurring in bovine brain: Isolation and structural determination

Abstract A new basic amino acid, hypusine, was isolated from the homogenate of bovine brain tissue by ion-exchange column chromatography. The structure of this amino acid was determined to be N 6 -4-amino-2-hydroxybutyl)-2,6-diaminohexanoic acid on the basis of its physical properties involving NMR and mass spectra, as well as chemical degradation including periodate oxidation and reduction with HI and P.

Isolation and identification of NG-Monomethyl NG, NG-Dimethyl- and NG,NG-Dimethylarginine from the hydrolysate of proteins of bovine brain

Abstract N G -Monomethylarginine was isolated from the hydrolysate of a protein fraction of bovine brain. Its identification was based on elementary analysis, alkaline hydrolysis, nuclear magnetic resonance, infrared spectrum, paper electrophoresis and chromatography. N G , N G - and N G , N G -dimethylarginine were also isolated from the same source and identified. Their concentrations were determined in the protein fractions of various organs and subcellular components of brain and liver of rats.

Isolation of γ-l-glutamyl-l-glutamic acid and γ-l-glutamyl-l-glutamine from bovine brain

Abstract Two peptides have been isolated from 28.5 kg of bovine brains using a combination of ion-exchange chromatographic separations. They were identified as γ- l -glutamyl- l -glutamic acid and γ- l -glutamyl- l -glutamine. The synthesis of these peptides has been described.

Changes in concentrations of polyamines and γ-aminobutyric acid and their formation in chick embryo brain during development

POLYAMISES including putrescine (Put) are thought to play important roles in the regulation of the tissue growth and there is much experimental evidence for the hypothesis that polyamines stimulate cell growth. However, little attention has been paid to the metabolism of polyamine in mammals. Recently SEILER er ul. (1971. 1973) reported that y-aminobutyric acid (GABA) is formed from putrescine in mouse brain and liver and fish brain. This synthetic pathway was also detected in neuroblastoma cells (KREMZSER er a/.. 1975) and chick embryo retina (DE MELLO el a/.. 1976). These findings led us to study changes of concentration of polyamines and GABA and their formation in chick embryo brain during development because putrescine is the precursor not only for polyamines. spermidine (Spd) and spermine (Sp), but also for GABA.

Identification of γ-glutamylserine, γ-glutamylalanine, γ-glutamylvaline and S-methylglutathione of bovine brain

Abstract Three γ-glutamyl dipeptides and a γ-glutamyl tripeptide were purified from bovine brain by a combination of ion-exchange chromatogaphic techniques. These were identified as γ-glutamylserine, γ-glutamylalanine, γ-glutamylvaline and S -methylglutathione by acid hydrolysis, terminal amino acid determination and comparison of paper chromatographic and paper electrophoretic properties of the isolated compounds with those of synthetized peptides.

Studies on formation of gamma glutamylamines in rat brain and their synthetic and catabolic enzymes

γ‐Glutamylation of p‐tyramine, noradrenaline, dopamine and serotonin in rat brains was demonstrated by intraventricular injections of the radioactive amines and isolation of the γ‐glutamylamines from the acidic extract of the rat brains. Formation of these γ‐glutamylamines was proved to be catalysed by γ‐glutamyltranspeptidase prepared from both rat kidney and brain. However, these compounds were degraded by γ‐glutamylcyclotransferase of rat brain, but not by the emzyme of rat kidney.

α-(γ-AMINOBUTYRYL)-LYSINE IN MAMMALIAN BRAIN: ITS IDENTIFICATION AND DISTRIBUTION

Abstract— α‐(γ‐Aminobutyryi)‐lysine was identified in rabbit brain. This compound was detected exclusively in the brain of mammals, but not in other tissues. It is not concentrated in any particular region of the rabbit brain.

Isolation and identification of γ-l-glutamylglycine from bovine brain

A peptide has been isolated from 28.5 kg of bovine brains through ion-exchange chromatography, and identified as γ-l-glutamylglycine. The identification was based on elementary analysis, determination of amino acid sequence, infrared spectrum, paper chromatography, paper electrophoresis and determination of configuration of glutamyl residue by l-glutamic acid decarboxylase (EC 4.1.1.15). The synthesis of α- and γ-l-glutamylglycine are also described.

OCCURRENCE AND FORMATION OF γ‐GLUTAMYLPUTRESCINE IN MAMMALIAN BRAIN

—An unknown radioactive compound was detected in the basic fraction of the trichloroacetic acid extract of rat brain injected with radioactive putrescine. This compound was purified from bovine brain and identified as γ‐glutamylputrescine by comparison of its behaviour with that of the synthesized glutamylamides. The amide seemed to be metabolized as rapidly as putrescine in rat brain.

FORMATION OF PUTREANINE, N-(4-AMINOBUTYL)-3-AMINOPROPIONIC ACID FROM SPERMIDINE IN RAT BRAIN AND LIVER

Abstract— Putreanine was proven to be formed from spermidine in rat brain by intra‐ventricular injection of radioactive spermidine. The ability to form putreanine from spermidine was also found in rat liver. The turnover rate of putreanine was slower in rat brain than in rat liver.