0000000000900713
AUTHOR
Lorena Latorre García
Análisis estructural y modificación funcional de la glucoamilasa de Saccharomyces cerevisiae var diastaticus.
La glucoamilasa (GA) es uno de los enzimas producidos en mayor cantidad por la industria biotecnológica. Se emplea en el procesado del almidón degradándolo y liberando residuos de glucosa al medio. Saccharomyces cerevisiae (var. diastaticus) posee genes denominados STA que codifican GAs (Yamashita et al 1987). Este enzima presenta una estructura atípica ya que posee un dominio N-terminal, rico en residuos de serina y treonina (STRD o "Ser and Thr rich-domain") ausente en las otras GAs fúngicas y carece de un dominio de unión al almidón o (SBD o "Starch Binding domain) presente en la mayoría enzimas. La ausencia de este dominio hace que la GA de S. cerevisiae sea ineficaz en la degradación d…
Isolation of aCandida albicans gene, tightly linked toURA3, coding for a putative transcription factor that suppresses aSaccharomyces cerevisiaeaft1 mutation
A pathogen such as C. albicans needs an ef®cient mechanism of iron uptake in an iron- restricted environment such as is the human body. A ferric-reductase activity regulated by iron and copper, and analogous to that in S. cerevisiae, has been described in C. albicans. We have developed an in-plate protocol for the isolation of clones that complement an aft1 mutation in S. cerevisiae that makes cells dependent on iron for growth. After transformation of S. cerevisiae aft1 with a C. albicans library, we have selected clones that grow in conditions of iron de®ciency and share an identical plasmid, pIRO1, with a 4500 bp insert containing the URA3 gene and an ORF (IRO1) responsible for the suppr…