Examine the 2 pairs of proteins below. In each case, these are enzymes that cata

Question

Examine the 2 pairs of proteins below. In each case, these are enzymes that catalyze the same reaction in different species. The question is: are they related or not? i.e. Are the structures essentially the same? Often you can get similar reactions from proteins that evolved from a common ancestor (e.g. trypsin and chymotrypsin). Sometimes the same reaction can be catalyzed by proteins with very different evolutionary origins and with very different structures (e.g. trypsin and subtilisin). Your job is to decide if these proteins have fundamentally different folds or if they have basically the same fold. Briefly justify your answer (3 sentences). Aldolase from an Archaea and a Bacillus (PR1A & PR1B) Isochorismate synthase from a Proteobacterium and a Bacillus (PR2A & PR2B)

Explanation / Answer

Aldolase is also known as fructose-bisphosphate aldolase. Aldolase found in Archaea show unique quaternery and tertiary structure compared to the aldolase found in Bacillus. Aldolase found in Archaea and bacillus follow different enzymatic mechanism.Aldolase found in Archaea utilise the e-amino group of active site lysine and form schiff base with the substrate whereas Aldolase found in bacillus use divalent metal ion to stablise intermediate. Both the aldolase share common evolutionary origin.

Protobacteria are Gram negative bacteria. In proteobacterium two different type of gene entC and manF coded Isochorismate synthase and in Bacillus two different type of gene dhbC and manF coded Isochorismate synthase.

Related Questions

Navigate

• Browse (All)
• Browse E
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.