INVESTIGADORES
IGLESIAS Alberto Alvaro
artículos
Título:
Involvement of Arginine Residues in the Allosteric Activation and Inhibition of Synechocystis PCC 6803 ADPglucose Pyrophosphorylase
Autor/es:
A.A. IGLESIAS, G. KAKEFUDA, J. PREISS
Revista:
JOURNAL OF PROTEIN CHEMISTRY
Referencias:
Año: 1992 vol. 11 p. 119 - 128
ISSN:
0277-8033
Resumen:
J Protein Chem. 1992 Apr;11(2):119-28. Related Articles, <!-- var Menu1326983 = [ ["UseLocalConfig", "jsmenu3Config", "", ""], ["Compound (MeSH Keyword)" , "window.top.location='/sites/entrez?Db=pccompound&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pccompound_mesh&LinkReadableName=Compound%20(MeSH%20Keyword)&IdsFromResult=1326983&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVCitation' ", "", ""], ["Substance (MeSH Keyword)" , "window.top.location='/sites/entrez?Db=pcsubstance&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pcsubstance_mesh&LinkReadableName=Substance%20(MeSH%20Keyword)&IdsFromResult=1326983&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVCitation' ", "", ""], ["Taxonomy via GenBank" , "window.top.location='/sites/entrez?Db=taxonomy&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_taxonomy_entrez&LinkReadableName=Taxonomy%20via%20GenBank&IdsFromResult=1326983&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVCitation' ", "", ""], ["Protein" , "window.top.location='/sites/entrez?Db=protein&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_protein&LinkReadableName=Protein&IdsFromResult=1326983&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVCitation' ", "", ""], ["Cited in PMC" , "window.top.location='http://www.pubmedcentral.gov/tocrender.fcgi?action=cited&tool=pubmed&pubmedid=1326983&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVCitation&ordinalpos=1' ", "", ""], ["LinkOut", "window.top.location='/sites/entrez?Cmd=ShowLinkOut&Db=pubmed&TermToSearch=1326983&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVCitation' ", "", ""] ] -->LinksInvolvement of arginine residues in the allosteric activation and inhibition of Synechocystis PCC 6803 ADPglucose pyrophosphorylase.Iglesias AA, Kakefuda G, Preiss J.Department of Biochemistry, Michigan State University, East Lansing 48824.ADPglucose pyrophosphorylase (EC 2.7.7.27) from the cyanobacterium Synechocystis PCC 6803 was desensitized to the effects of allosteric ligands by treatment with the arginine reagent, phenylglyoxal. Enzyme modification by phenylglyoxal resulted in inactivation when the enzyme was assayed under 3P-glycerate-activated conditions. There was little loss of the catalytic activity assayed in the absence of activator. Pi, 3P-glycerate, and pyridoxal-P were able to protect the enzyme from inactivation, whereas substrates gave minimal protection. The protective effect exhibited by Pi and 3P-glycerate was dependent on effector concentration. MgCl2 enhanced the protection afforded by 3P-glycerate. The enzyme partially modified by phenylglyoxal was more resistant to 3P-glycerate activation and Pi inhibition than the unmodified form. Vmax at saturating 3P-glycerate concentrations and the apparent affinity of the enzyme toward Pi were decreased upon phenylglyoxal modification. Incorporation of labeled phenylglyoxal into the enzyme was proportional to the loss of activity. Pi and 3P-glycerate nearly completely prevented incorporation of the reagent to the protein. Results suggest that one arginine residue per mol of enzyme subunit is involved in the binding of allosteric effector in the cyanobacterial ADPglucose pyrophosphorylase.