M M Sola, R Salto, F J Oliver, M Gutiérrez, A M Vargas
{"title":"Regulation of rat-renal cortex phosphofructokinase activity by pH.","authors":"M M Sola, R Salto, F J Oliver, M Gutiérrez, A M Vargas","doi":"10.1159/000468663","DOIUrl":null,"url":null,"abstract":"<p><p>The activity of phosphofructokinase purified from rat kidney cortex has been assayed at two different pH values. At pH 7 the enzyme showed cooperativity for the binding of fructose 6-phosphate (Fru-6-P) and a strong allosteric inhibition by ATP. When the assays were done at pH 8 hyperbolic kinetics were observed for both substrates, a smaller inhibition by ATP was observed and the Vmax for ATP and for Fru-6-P was higher than at pH 7. A sequential reaction mechanism was inferred. Results are discussed in terms of the importance of a reduced hexose-phosphate cycling rate during metabolic acidosis induced by exercise.</p>","PeriodicalId":11854,"journal":{"name":"Enzyme & protein","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1993-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000468663","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Enzyme & protein","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1159/000468663","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 2
Abstract
The activity of phosphofructokinase purified from rat kidney cortex has been assayed at two different pH values. At pH 7 the enzyme showed cooperativity for the binding of fructose 6-phosphate (Fru-6-P) and a strong allosteric inhibition by ATP. When the assays were done at pH 8 hyperbolic kinetics were observed for both substrates, a smaller inhibition by ATP was observed and the Vmax for ATP and for Fru-6-P was higher than at pH 7. A sequential reaction mechanism was inferred. Results are discussed in terms of the importance of a reduced hexose-phosphate cycling rate during metabolic acidosis induced by exercise.