GRE Subject Test: Biochemistry, Cell, and Molecular Biology › Macromolecules and Enzymes
The third step of glycolysis converts fructose-6-phosphate to fructose-1,6-bisphosphate. What type of enzyme mediates this?
A kinase
A phosphatase
A reductase
A polymerase
An isomerase
Kinases are enzyme that catalyze the transfer of a phosphate group from ATP to a substrate molecule. The phosphorylation of fructose-6-phosphate to fructose-1,6-phosphate is mediated by a kinase phosphofructokinase.
The third step of glycolysis converts fructose-6-phosphate to fructose-1,6-bisphosphate. What type of enzyme mediates this?
A kinase
A phosphatase
A reductase
A polymerase
An isomerase
Kinases are enzyme that catalyze the transfer of a phosphate group from ATP to a substrate molecule. The phosphorylation of fructose-6-phosphate to fructose-1,6-phosphate is mediated by a kinase phosphofructokinase.
The third step of glycolysis converts fructose-6-phosphate to fructose-1,6-bisphosphate. What type of enzyme mediates this?
A kinase
A phosphatase
A reductase
A polymerase
An isomerase
Kinases are enzyme that catalyze the transfer of a phosphate group from ATP to a substrate molecule. The phosphorylation of fructose-6-phosphate to fructose-1,6-phosphate is mediated by a kinase phosphofructokinase.
The third step of glycolysis converts fructose-6-phosphate to fructose-1,6-bisphosphate. What type of enzyme mediates this?
A kinase
A phosphatase
A reductase
A polymerase
An isomerase
Kinases are enzyme that catalyze the transfer of a phosphate group from ATP to a substrate molecule. The phosphorylation of fructose-6-phosphate to fructose-1,6-phosphate is mediated by a kinase phosphofructokinase.
In a Lineweaver-Burk plot, what quantity determines the y-intercept?
A Lineweaver-Burk plot is a way to graphically represent enzyme kinetics. It is convenient because several portions of the graph readily display important information, such as rate constants. The y-intercept in particular is useful because it represents the reciprocal of the maximum velocity. The x-intercept describes the negative reciprocal of the Michaelis constant. The slope is the quotient of the Michaelis constant over the maximum velocity.
In a Lineweaver-Burk plot, what quantity determines the y-intercept?
A Lineweaver-Burk plot is a way to graphically represent enzyme kinetics. It is convenient because several portions of the graph readily display important information, such as rate constants. The y-intercept in particular is useful because it represents the reciprocal of the maximum velocity. The x-intercept describes the negative reciprocal of the Michaelis constant. The slope is the quotient of the Michaelis constant over the maximum velocity.
In a Lineweaver-Burk plot, what quantity determines the y-intercept?
A Lineweaver-Burk plot is a way to graphically represent enzyme kinetics. It is convenient because several portions of the graph readily display important information, such as rate constants. The y-intercept in particular is useful because it represents the reciprocal of the maximum velocity. The x-intercept describes the negative reciprocal of the Michaelis constant. The slope is the quotient of the Michaelis constant over the maximum velocity.
In a Lineweaver-Burk plot, what quantity determines the y-intercept?
A Lineweaver-Burk plot is a way to graphically represent enzyme kinetics. It is convenient because several portions of the graph readily display important information, such as rate constants. The y-intercept in particular is useful because it represents the reciprocal of the maximum velocity. The x-intercept describes the negative reciprocal of the Michaelis constant. The slope is the quotient of the Michaelis constant over the maximum velocity.
Which of the following best describes when an inhibitor binds an enzyme at a separate site from the active site, but only when the enzyme and substrate are already bound in complex?
Uncompetitive inhibition
Non-competitive inhibition
Competitive inhibition
Allostery
Reversible inhibition
The correct answer is uncompetitive inhibition. The formation of a enzyme-substrate complex creates an alternative site on the enzyme for an inhibitor to bind. This mechanism is considered uncompetitive because the inhibitor and substrate are not competing for the same binding site on the enzyme.
Which of the following best describes when an inhibitor binds an enzyme at a separate site from the active site, but only when the enzyme and substrate are already bound in complex?
Uncompetitive inhibition
Non-competitive inhibition
Competitive inhibition
Allostery
Reversible inhibition
The correct answer is uncompetitive inhibition. The formation of a enzyme-substrate complex creates an alternative site on the enzyme for an inhibitor to bind. This mechanism is considered uncompetitive because the inhibitor and substrate are not competing for the same binding site on the enzyme.