1xfn: Difference between revisions

[[Image:1xfn.gif|left|200px]]

'''NMR structure of the ground state of the photoactive yellow protein lacking the N-terminal part'''

The N-terminally truncated variant of photoactive yellow protein (Delta25-PYP) undergoes a very similar photocycle as the corresponding wild-type protein (WT-PYP), although the lifetime of its light-illuminated (pB) state is much longer. This has allowed determination of the structure of both its dark- (pG) as well as its pB-state in solution by nuclear magnetic resonance (NMR) spectroscopy. The pG structure shows a well-defined fold, similar to WT-PYP and the X-ray structure of the pG state of Delta25-PYP. In the long-lived photocycle intermediate pB, the central beta sheet is still intact, as well as a small part of one alpha helix. The remainder of pB is unfolded and highly flexible, as evidenced by results from proton-deuterium exchange and NMR relaxation studies. Thus, the partially unfolded nature of the presumed signaling state of PYP in solution, as suggested previously, has now been structurally demonstrated.

1XFN is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Halorhodospira_halophila Halorhodospira halophila]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XFN OCA].  

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