Shared control of maltose and trehalose utilization in Candida utilis
Braz. j. med. biol. res
; 36(7): 829-837, July 2003. tab, graf
Artigo
em Inglês
| LILACS
| ID: lil-340686
Biblioteca responsável:
BR1.1
RESUMO
Trehalose biosynthesis and its hydrolysis have been extensively studied in yeast, but few reports have addressed the catabolism of exogenously supplied trehalose. Here we report the catabolism of exogenous trehalose by Candida utilis. In contrast to the biphasic growth in glucose, the growth of C. utilis in a mineral medium with trehalose as the sole carbon and energy source is aerobic and exhibits the Kluyver effect. Trehalose is transported into the cell by an inducible trehalose transporter (K M of 8 mM and V MAX of 1.8 æmol trehalose min-1 mg cell (dry weight)-1. The activity of the trehalose transporter is high in cells growing in media containing trehalose or maltose and very low or absent during the growth in glucose or glycerol. Similarly, total trehalase activity was increased from about 1.0 mU/mg protein in cells growing in glucose to 39.0 and 56.2 mU/mg protein in cells growing in maltose and trehalose, respectively. Acidic and neutral trehalase activities increased during the growth in trehalose, with neutral trehalase contributing to about 70 percent of the total activity. In addition to the increased activities of the trehalose transporter and trehalases, growth in trehalose promoted the increase in the activity of alpha-glucosidase and the maltose transporter. These results clearly indicate that maltose and trehalose promote the increase of the enzymatic activities necessary to their catabolism but are also able to stimulate each other's catabolism, as reported to occur in Escherichia coli. We show here for the first time that trehalose induces the catabolism of maltose in yeast
Texto completo:
Disponível
Coleções:
Bases de dados internacionais
Base de dados:
LILACS
Assunto principal:
Trealase
/
Trealose
/
Candida
/
Maltose
Idioma:
Inglês
Revista:
Braz. j. med. biol. res
Assunto da revista:
Biologia
/
Medicina
Ano de publicação:
2003
Tipo de documento:
Artigo
/
Documento de projeto
País de afiliação:
Brasil
Instituição/País de afiliação:
Universidade Federal do Rio de Janeiro/BR
/
Universidade de Säo Paulo/BR