Question

Define the difference between each pair of terms:

Isozyme vs. Zymogen

Homotropic Effects vs. Heterotropic Effects

Consensus Sequence vs Pseudosubstrate Sequence

Answer 1

1. zymogen : The basic difference in both is that these enzymes are initially produced from an inactive precursor form known as zymogen. A number of the alimentary digestive enzymes belongs to this group including pepsin, trypsin and chemotrypsin .

Isozymes : While, these enzymes already exists as their multimeric forms such as tetramers or can be defined as The several different enzyme molecules , all of which catalyse the same chemical reaction, have been isolated from a single tisssue. Such families of enzymes are called as isozymes. Among the various isozymes the lactic hydrogenases have been most extensively known, and five different forms identified.

2. Homotropic effects : or the interactions between the identical ligans . Homotropic effects are present in most of the allosteric proteins for atleast one type of ligand (substrate , inhibitor or activator). These effects are always cooperative. It can also say the binding of primary ligand(substrate) can alter affinity ofvother binding sites on molecule for that same ligand.

Heterotropic effects : or the interactions between the different ligands . heterotropic effects may be either cooperative  or antagonistic. Binding of other ligands (regulatory signalling molecules), to different sites from the primary ligand can cause confirmational changes that alters binding affinity or catalytic activity of primary ligands.

Heterotropic interaction can be often change by experimental conditions into homotropic ones.

3. consensus sequence : It is a sequence of neucleotides ( the basic structural units in DNA, RNA etc) found with minor variations and similar functions in order of most frequent residues. It can vary in length and sets but not in order of repeatition.The primary features of cinsensus sequence are its conserved residues and common functional roles, despite its genetic location. It also serves as a measurement of functional significance in over of generations steps.

pseudosubstrate sequence : It is a sequence of neucleotides that found as the mimic of substrate of an enzyme that means act as the target sequence but lacks an OH-bearing side chain at the right place. the pseudo substrate sequence binds to the active site of catalytic subunits , blocking their activity.