RESUMEN

The crystal structure of the tetrameric glycolytic enzyme phosphoglycerate mutase from the yeast Saccharomyces cerevisiae has been determined to 1.7 A resolution in complex with the sugar substrate. The difference map indicates that 3-phosphoglycerate is bound at the base of a 12 A cleft, positioning C2 of the substrate within 3.5 A of the primary catalytic residue, histidine 8.

Asunto(s)

Ácidos Glicéricos/química , Fosfoglicerato Mutasa/química , Saccharomyces cerevisiae/enzimología , Sitios de Unión , Cristalografía por Rayos X , Proteínas Fúngicas/química , Enlace de Hidrógeno , Modelos Moleculares , Sulfatos/química

RESUMEN

The enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from the archaea shows low sequence identity (16-20%) with its eubacterial and eukaryotic counterparts. The crystal structure of the apo GAPDH from Sulfolobus solfataricus has been determined by multiple isomorphous replacement at 2.05 A resolution. The enzyme has several differences in secondary structure when compared with eubacterial GAPDHs, with an overall increase in the number of alpha-helices. There is a relocation of the active-site residues within the catalytic domain of the enzyme. The thermostability of the S. solfataricus enzyme can be attributed to a combination of an ion pair cluster and an intrasubunit disulphide bond.

Asunto(s)

Gliceraldehído-3-Fosfato Deshidrogenasas/química , Sulfolobus/enzimología , Secuencia de Aminoácidos , Dominio Catalítico , Cristalografía por Rayos X , Estabilidad de Enzimas , Geobacillus stearothermophilus/enzimología , Geobacillus stearothermophilus/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Homología de Secuencia de Aminoácido , Electricidad Estática , Sulfolobus/genética , Temperatura

Asunto(s)

Gliceraldehído-3-Fosfato Deshidrogenasas/aislamiento & purificación , Fosfoglicerato Quinasa/aislamiento & purificación , Sulfolobus/enzimología , Cromatografía de Afinidad , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Cristalización , Glucólisis , Indicadores y Reactivos