Both glyceraldehyde 3-phosphate and dihydroxyacetone phosphate are substrates for the enzyme triose phosphate isomerase. In a...

Both glyceraldehyde 3-phosphate and dihydroxyacetone phosphate are substrates for the enzyme triose phosphate isomerase. In a study by Knowles et al the k_M for glyceraldehyde 3-phosphate was determined to be 0.47mM with a Vmax of about 410 uM/min. Whereas, for the substrate dihydroxyacetone phosphate the k_M was determined to be 0.97 mM and the Vmax was about 41 uM/min. (Biochem J 129 (2) 1972:301-310). Triose phosphate isomerase has a relatively weak affinity for _______

A. glyceraldehyde 3-phosphate because the k_M is lower in comparison

B. dihydroxyacetone phosphate because the k_M is higher in comparison

C. glyceraldehyde 3-phosphate because the Vmax is higher in comparison

D. dihydroxyacetone phosphate because the Vmax is lower in comparison

Expert Solution

Substrate (S) binds catalytic site of enzyme (E) to produce a enzyme-substrate (E-S) complex and eventually a product. This binding is mostly reversible and sometimes could be irreversible.

Enzyme is a catalyst so it is formed back in a reaction.

Talking about reaction rate, at the very beginning enzyme has a lot of availble catalytic sites. They accommodate the low levels substrate to facilitate the reaction.

As you increase the concentration of substrate, the catalytic sites get saturated with substrate and no more sites are available to bind. And you end up in excess substrate which could be utilized only when how fast the enzyme forms a product.

Here the substrate concentration is Km also called Michaleis-Menton constant. And the maximum rate when an enyme got saturated is Vmax. The relation between reaction rate and substraate concetration give is hyperbolic as shown below.

Km is the substrate concetration where the reaction rate is half-maximum i.e. 1/2 Vmax

An enzyme with high Km usually has low affinity for its substrate. Low Km indicate high affinity. Lower the Km faster the reaction and larger the Vmax.

So the answer for the abov question is

Triose phosphate isomerase has a relatively weak affinity for dihydroxyacetone phosphate because the Km is higher in comparison.

Answer is B

queen_honey_blossom answered 2 years ago

In the glycolytic pathway, the enzyme triose phosphate isomerase catalyzes the conversion of of dihydroxyacetone phosphate...

In the glycolytic pathway, the enzyme triose phosphate isomerase catalyzes the conversion of of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate, which is then immediately utilized by glyceraldehyde-3-phosphate hydrogenase to continue through glycolysis. In an experimental cell culture model, inhibition of triose phosphate isomerase leads to cell death in anaerobic conditions. These cells survive, however under aerobic conditions. Please explain these findings. In your answer consider the energy production in aerobic vs. anaerobic metabolism.

A)Triosephosphate isomerase(TIM)converts dihydroxyacetone phosphate (DHAP) into glyceraldehyde-3-phosphate (GAP) and vice-versa. This is one of the best-understood...

A)Triosephosphate isomerase(TIM)converts dihydroxyacetone phosphate (DHAP) into glyceraldehyde-3-phosphate (GAP) and vice-versa. This is one of the best-understood enzyme reactions. It has been studied extensively and we know the two critical side chains in the active site of TIM that catalyze the isomerization reaction. Write the mechanism of TIM showing the two catalytic side chains. B) In the TIM reaction, the histidine residue starts off neutral, not positively charged (as one might expect since it donates a proton to the O-group). Explain...

Fructose-1,6-bisphosphate (FBP) <=====> glyceraldehyde-3-phosphate (GAP) + dihydroxyacetone phosphate (DHAP) The standard free energy change for this...

Fructose-1,6-bisphosphate (FBP) <=====> glyceraldehyde-3-phosphate (GAP) + dihydroxyacetone phosphate (DHAP) The standard free energy change for this reaction is +22.8 kJ/mol. Under actual conditions in the cell the concentrations of GAP,DHAP,and FBP are 0.5 mM, 0.3 mM, and 6.0 mM respectively. Given this information calculate the actual free energy change for this reaction in the cell at a temperature of 37 oC. Provide your answer (just the numerical part) in kJ/mole to two signicant figures

A biochemist studying the activity of the enzyme triose phosphate isomerase (TPI) in a species of...

A biochemist studying the activity of the enzyme triose phosphate isomerase (TPI) in a species of Drosophila wishes to know if the mean activity of this enzyme is the same at pH = 5 and at pH = 8. Assuming activities in µM/min are normally distributed, determine if the mean activities of TPI are significantly different at these two pH levels. pH = 5 11.1 10.0 13.3 10.5 11.3 pH = 8 12.0 15.3 15.1 15.0 13.2 Suppose that you...

The table below contains data on the enzyme activity of mannose-6-phosphate isomerase (MPI) for three different...

The table below contains data on the enzyme activity of mannose-6-phosphate isomerase (MPI) for three different genotypes (SS, FS, FF) in the amphipod crustacean Platorchestia platensis. Because the effects of sex are not known, specimens were classified by sex. Conduct a two-way ANOVA on this dataset. Test for the effect of genotype, the effect of sex, and whether there is an interaction effect between two factors. Show all calculations and state your conclusions. SS FS FF Females 3.65 3.57 3.99...

1.) a key reaction in glycolysis is the isomerization of dihydroxyacetone into gylceraldehyde-3-phosphate. dhap<> G-3-P Delta...

1.) a key reaction in glycolysis is the isomerization of dihydroxyacetone into gylceraldehyde-3-phosphate. dhap<> G-3-P Delta G = 7.5 kj/mol a.) whis is favored in this equilibrium, DHAP OR G-3-P? B.) Calculate the equilibrium constant for the reaction at 25 degrees C. C.) in the cell depletion of G-3-P makes the reaction proceed. what will delta G be if the temperature concentration of G-3-P is always kept 1/100 of the concentration of DHAP at a temp of 37 degrees C?

1. What is the effect that glyceraldehyde 3 phosphate dehydrogenase has on cells? 2. What would...

1. What is the effect that glyceraldehyde 3 phosphate dehydrogenase has on cells? 2. What would happen in the absence of Pol1, if the the primers are not replaced by DNA and if Pol 3 was absent and no DNA synthesis occured? 3. How does the phase where Glucose forms glucose 6 phosphate differ from the phase where PGA forms pyruvate in terms of reaction coupling to overcome thermodynamic hurdles for glycolysis to occur ***

QUESTION 39 The molecule that traps the sun's energy is   ATP.  chloroplast.  chlorophyll.  glyceraldehyde-3-phosphate &nbsp

QUESTION 39 The molecule that traps the sun's energy is   ATP.  chloroplast.  chlorophyll.  glyceraldehyde-3-phosphate QUESTION 42 Deleterious mutations increase the fitness of the organism. True False QUESTION 47 The light-independent reactions of photosynthesis (Calvin cycle) take place in the   cytoplasm.  grana.  thylakoids.  stroma. QUESTION 48 Cellular respiration is endergonic. True False QUESTION 49 The ATP and NADPH produced in the light-dependent reaction stage   are the end products of photosynthesis.  become reactants for cellular respiration.  are waste products that the...

1) write the balanced net reaction of the conversion of glyceraldehyde 3-phosphate into lactate 2)If all...

1) write the balanced net reaction of the conversion of glyceraldehyde 3-phosphate into lactate 2)If all the glucose were metabolized through that 2,3-BPG shunt into lactate, what should be the net reaction for the conversion of glucose to lactate?

In order to produce three glyceraldehyde-3-phosphate molecules that the plant could use to make other organic...

In order to produce three glyceraldehyde-3-phosphate molecules that the plant could use to make other organic molecules, how many CO2 molecules would have to enter the Calvin Cycle? 3 6 9 12 Genes A and B are on the same chromosome. If a person has one chromosome with the alleles AB and a second chromosome with the alleles ab, how could they produce a gamete with a chromosome containing the alleles Ab or aB? independent assortment random fertilization crossing over...

Question