Phosphofructokinase the key regulatory enzyme in the glycolytic pathway, catalyz
ID: 269360 • Letter: P
Question
Phosphofructokinase the key regulatory enzyme in the glycolytic pathway, catalyzes conversion of F6P to F1,6BP and ADP in the presence of ATP. t the following Mg dependent Recent ly, some site-directed mutagenesis work was performed and the resulting enzymes with substituted amino acids were kinetically characterized and shown in the table below. Convention in which amino acid substitutions are made - Asp 32Ala indicates that an Asp was substituted with Ala at position 532) PhosphofructokinaseKm (ATP) uM Native (wildtype) Km (F6P) mM 25.0 35.0 23.0 22.4 koat sec 26.9 21.6 0.29 Lys213Ala Arg322Ala Arg322Lys 2.9 0.78 0.21 0.62 2.1 For the following questions, take into the account the functional groups of the side chains, and briefly explain what role the residues may be playing in the active site (based on how Km and Kcat are affected) and how it affects the enzyme catalyze reaction 1) what is the major effect of the substitution at Lys213 2) what is the major effect of the substitution at Arg322? 3)Design an experiment to test the predicted role of Lys213Explanation / Answer
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