Phosphoenolpyruvate carboxykinase (PEPCK, figure below)catalyzes first committed (rate-limiting) step in hepatic gluconeogenesis, namely the reversible decarboxylation of oxaloacetate to phosphoenolpyruvate (PEP) and carbon dioxide. This reaction can occur using either ATP or GTP as a source of the phosphate.Which following mutation can potentially improve the binding affinity of the substrate for this enzyme? a. LYS254ARG b. LYS254ASP c. ARG333GLU d. THR255GLY

Phosphoenolpyruvate carboxykinase (PEPCK, figure below)catalyzes first committed (rate-limiting) step in hepatic gluconeogenesis, namely the reversible decarboxylation of oxaloacetate to phosphoenolpyruvate (PEP) and carbon dioxide. This reaction can occur using either ATP or GTP as a source of the phosphate.Which following mutation can potentially improve the binding affinity of the substrate for this enzyme? a. LYS254ARG b. LYS254ASP c. ARG333GLU d. THR255GLY

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter16: The Digestive System

Section: Chapter Questions

Problem 4TAHL

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For each of the following conditions, state whether this condition would be occurring during gluconeogenesis, glycolysis, or both in liver cells. a. Transporting malate from the cytosol into the mitochondria. _____________ b. Transporting pyruvate from the cytosol into the mitochondria. _____________ c. We would have an increased (or increasing) concentration of F26BP. __________ d. Increased concentration of F6P.__________ e. Hexokinase IV (or glucokinase) is found in the nucleus of the cell. __________ f. The enzyme that synthesizes/breaks down F26BP is phosphorylated. __________ g. Elevated levels of glucagon in the blood. ____________
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