OBJECTIVE LIFE SCIENCE
BIOCHEMISTRY
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Hexokinase
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Aldolase
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PhosphoFructoKinase
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Enolase
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Detailed explanation-1: -Fructose-1, 6-bisphosphate aldolase catalyzes the conversion of fructose-1, 6-bisphosphatealdol to dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (G3P). Tagatose-1, 6-bisphosphate aldolase catalyzes the aldol condensation of DHAP with G3P to produce tagatose 1, 6-bisphosphate.
Detailed explanation-2: -Dihydroxyacetone phosphate (DHAP) is converted to glyceradehyde-3-phosphate (G3P) by the enzyme triose phosphate isomerase. As the name suggests, this enzyme catalyzes the isomerization of a three-carbon sugar into another three-carbon sugar.
Detailed explanation-3: -Aldolase is a cytoplasmic enzyme involved in glucose and fructose metabolism. It specifically catalyzes the reversible reaction of converting fructose 1, 6-bisphosphate into dihydroxyacetone phosphate (DHAP) and glyceraldehydes 3-phosphate.
Detailed explanation-4: -Dihydroxyacetone phosphate (DHAP, also glycerone phosphate in older texts) is the anion with the formula HOCH2C(O)CH2OPO32-. This anion is involved in many metabolic pathways, including the Calvin cycle in plants and glycolysis. It is the phosphate ester of dihydroxyacetone.
Detailed explanation-5: -The glyceraldehyde 3-phopshate lies directly on the glycolytic pathway and so goes on to stage three. On the other hand, dihydroxyacetone phosphate does not and so needs to be converted into a glyceraldehyde 3-phopshate molecule before it can be used by the glycolytic pathway.