Structural Evidence for Evolution of the β/α Barrel Scaffold by Gene Duplication and Fusion

Horng –uei Lii

Background

What is β/α Barrel ?

β/α Barrel (I)

Are found in many proteins(enzymes) The eight-stranded β/α Barrel structure

are one of the largest and most regular of all domain structure

β/α Barrel(II)

Different structure and function

Loops---varies, functional domain

Evolution material

TIM barrel

Triosephosphate isomerase

Introduction Evolution Material Computational Tool Genome Protein Dtata

Materials

Thermotoga maritimaHisA & HisF

HisA

Converts (ProFAR) to (PRFAR)

HisF

Catalyze condensation of PRFAR and ammonia,

AICAR and ImGPHisF:HisH cowork

Methods

X-ray analysis Multi-sequence alignment Superimpose Mutual residual activities

Conclusion

Half-barrel Ancestor Duplication and Fusion Model

Application

Subdomain structures:Genome searchFunctionally and

structurally related proteins

Thank you!