Abstract Objective Phenylketonuria (PKU) is caused by a specific mutation of the phenylalanine hydroxylase (PAH) gene. The deficiency PAH results in high levels (Phe), low tyrosine (Tyr), and reduced catecholamine neurotransmitters. majority PKU patients, if untreated, develop severe mental retardation. contribution Phe Tyr retardation largely unknown. In this study, we used organic hippocampal...

Background & Aims: Tyrosinase is the most important enzyme in the production of pigments of the skin, eyes, and hair follicles. The enzyme is encoded by tyrosinase gene (TYR) or oculocutaneous albinism type 1A (OCA1A). Mutations in TYR gene result in pigmentation disorders such as albinism in humans. In view of the large number of mutations reported in this gene, the aim of this study was to id...

Hydroxyl radical converts Phe to para-, meta-, and ortho-Tyr (p-Tyr, m-Tyr, o-Tyr), while Phe is converted enzymatically to p-Tyr in the kidney and could serve as substrate for gluconeogenesis. Pathological isoforms m- and o-Tyr are supposed to be involved in development of hormone resistances. Role of Phe and the three Tyr isoforms in influencing insulin need was examined in 25 nondiabetic sep...

Bu çalışmada HT-29, Hela ve MCF-7 hücre hatlarına karşı antikanser etki gösteren Cyclo(Tyr-Tyr) dipeptidinin olası en kararlı yedi konformasyonu tirozin aminoasilerinin χ yan zincir dihedral açılarına bağlı olarak konformasyon analizi yapılarak belirlenmiştir. Konformasyon sonrasında belirlenen konformasyonlara ait geometrik yapılar, zincire açıdaki değişimler konformerlerin toplam bağıl enerji...

Catecholamine synthesis and transmission in the brain are influenced by the availability of Tyr in the body. In this study, we compared the effects of oral administration of Tyr-containing dipeptides Ile-Tyr, Ser-Tyr, and Tyr-Pro with Tyr alone on catecholamine metabolism in the mouse brainstem. Among these dipeptides, Ile-Tyr administration led to increases in dopamine, the dopamine metabolite...

The aromatic (C−H) sulfenylation reaction with S-acetamidomethyl cysteine sulfoxide (Cys(Acm)(O)) can be Trp- or Tyr-selective under acidic conditions. red chloride anion team kicks the Cys(Acm)(O) ball into Trp goal, whereas blue trimethylsilyl Tyr goal. proton scoreline in stands supports both teams. More information found Research Article by A. Otaka and co-workers (DOI: 10.1002/chem.2023007...

background: oculocutaneous albinism type1 (oca1) is characterized by the absence of melanin pigmentation. the muta­tion on tyr gene makes oca1 as an autosomal recessive genetic disorder. in this study, we delineated the genetic analysis of an iranian family with four members affected with oca1.  methods: clinical exams and paraclinical test were performed for all patients of the case family, al...

retinal pigment epithelium is responsible for maintaining the structural integrity of the retina by an efficient defense against free radicals, photo-oxidative exposure and light energy. for this purpose the main rpe line of defense is melanosomes. melanin content of retinal pigment epithelium cells in adults and neonates reveals remarkable variations. in the current study we compared melanogen...