Essay !2 - Potential advantages of multidomain construction (Proteomics)- Code : KSI0002

Essay 2 – Potential advantages of multidomain construction with regard to the proteomics

Sangin Kim

 

Problem> Why proteins have the multidomain and what is the meaning?

 

First, Multi-domain construction makes it simple to evolve a new function Simple mutations of existing proteins has limitation to acquire new functions in terms of tIme and range and New functions can be created at a stroke by taking 2 existing functions & combining them also, Complementary functions & combining them then, Complementary functions and interfacial rearrangement lastly, Bifunctional enzyme can be created by taking the genes for 2 enzymes and fusing the together.

 

Second, multidomain construction make it simple to introduce control and regulation in terms of allosteric regulation and covalent modification - Signal transduction & Protein and protein interactions.

 

Third, Multidomain construction makes an effective enzyme. Enzyme catalyzed reactions need multiple steps ( Conformational changes ) and a simple rearrangement of a new residues ni a hinge rather than a restructing of the domain is favorable ,

 

Last, Multidomain construction simplifies folding and Assembly and stablizes the protein. Most modular proteins fold each module independently. Folding complexity is very approximately proportional to n^3 where n is the number of amino acid numbers. A large protein would be expected to fold up much more slowly than a small protein. 2 Domains of size n should fold up roughly 8 times faster than a single domain size 2n.

 

Reference

1. Protein sciences book - Introduction to protein 6th edition .