Lyases and Aldolase Activity

These flashcards cover key concepts regarding lyases and aldolase activity as discussed in the lecture.

What are lyases?

Enzymes that catalyze the unhydrolytic cleavage of the bond between two carbon atoms or between a carbon and a heteroatom.

What is aldolase and what are its main isoenzymes?

Aldolase is an enzyme that cleaves fructose-1,6-bisphosphate into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. Its main isoenzymes are A, B, and C.

Where is aldolase predominantly found in the body?

Aldolase is found primarily in the liver, skeletal muscle, and myocardium.

What is the principle of the serum aldolase activity determination?

Serum aldolase cleaves fructose-1,6-bisphosphate into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate, which react with hydrazine and are measured after hydrolysis with NaOH and treatment with 2,4-dinitrophenylhydrazine.

What are the manifestations of increased aldolase levels?

Increased levels can be seen in myocardial infarction, muscular dystrophy, and epidemic hepatitis.

What is the normal range for serum aldolase activity?

The normal range is 0.5-3.1 mU/mL.

What are the consequences of a diet rich in fructose on aldolase activity?

It leads to up-regulation of aldolase activity, resulting in conditions like hepatic steatosis and hypertriglyceridemia.

What genetic defect affects aldolase levels?

A genetic defect of aldolase B leads to fructose intolerance.

How is the extinction measured in the aldolase activity procedure?

The extinction is measured at a wavelength of 530nm.

What is the impact of different pathological processes on urea concentration in serum?

Increased urea levels may indicate renal failure or dietary influences, while decreased levels may point to liver disease.