Biosynthesis of polyuronides inMucor rouxii: Partial characterization of fucosyl transferase
1990; Academic Press; Volume: 14; Issue: 3 Linguagem: Inglês
10.1016/0147-5975(90)90020-t
ISSN1878-4399
AutoresSergio Camacho-Aguero, Rosalia Balcazar-Orozco, Arturo Flores-Carreo ́n,
Tópico(s)Seaweed-derived Bioactive Compounds
ResumoAbstract Most of the fucosyl transferase activity fromMucor rouxii was detected in a crude membrane fraction. The enzyme transferred l -fucose from GDP-fucose to endogenous and exogenous acceptors. When crude membrane fractions were treated with neutral detergents such as Trition X-100 or Brij 36 T enzyme activity became dependent on exogenous acceptors such as mucoric acid or mucoran. Brij-treated membrane fractions showed maximum fucosyl transferase activity at pH 6.5, and at a temperature between 22 and 28°C. The cations Mn2+, Mg2+, Co2+, Zn2+, Fe2+, and Ca2+ activated the enzyme about twofold. The former was slightly more stimulatory at 4 mM. Km for GDP-fucose was 10 μM. Evidence was obtained that mucoric acid serves as acceptor for fucosyl moieties. Acid hydrolysis of the product synthesized from GDP-fuc by Brij-treated membrane fractions revealed fucose as the major radioactive sugar.
Referência(s)