Sandbox 154: Difference between revisions

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=== Domains of F-actin Unit ===
=== Domains of F-actin Unit ===
Structure of a unit of F-actin with domains from a single polypeptide chain. Note that the nucleotide binding cleft occurs between the two domains and is also the region of ATP hydrolysis.  
The structure of a single unit of F-actin arises from one polypeptide chain with two domains, as observed by the figure on the left. The nucleotide binding cleft, site of ATP hydrolysis, can be observed between the two domains. Movement of the domains allows for the open and closed F-actin conformations.  
Domain movement is made possible by rotation about the <scene name='Sandbox_154/2zwh_helix_domains_2/1'> 141-142 and 335-336 peptide bonds</scene>, shown in purple. According to Oda et al.<ref name="oda" />Domain 2 is believed to tilt 20 degrees and fit itself with Domain 1, thus giving a flatter conformation than the free G-actin. It is not certain whether this flattening occurs before or after ATP hydrolysis.  
Domain movement is made possible by rotation about the <scene name='Sandbox_154/2zwh_helix_domains_2/1'> 141-142 and 335-336 peptide bonds</scene>, shown in purple. According to Oda et al., during the transition from G- to F- actin, Domain 2 is believed to tilt 20&deg;and fit itself with Domain 1, thus giving a flatter conformation than the free G-actin. It is not certain whether this flattening occurs before or after ATP hydrolysis<ref name="oda" />.


=== Stability ===
=== Stability ===