2bl0
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:2bl0.gif|left|200px]]<br /><applet load="2bl0" size=" | + | [[Image:2bl0.gif|left|200px]]<br /><applet load="2bl0" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2bl0, resolution 1.75Å" /> | caption="2bl0, resolution 1.75Å" /> | ||
'''PHYSARUM POLYCEPHALUM MYOSIN II REGULATORY DOMAIN'''<br /> | '''PHYSARUM POLYCEPHALUM MYOSIN II REGULATORY DOMAIN'''<br /> | ||
| Line 7: | Line 7: | ||
==About this Structure== | ==About this Structure== | ||
| - | 2BL0 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Physarum_polycephalum Physarum polycephalum] with CA as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Transferred_entry:_3.6.4.1 Transferred entry: 3.6.4.1], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.1.32 3.6.1.32] Known structural/functional Site: <scene name='pdbsite=AC1:Ca Binding Site For Chain C'>AC1</scene>. Full crystallographic information is available from [http:// | + | 2BL0 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Physarum_polycephalum Physarum polycephalum] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Transferred_entry:_3.6.4.1 Transferred entry: 3.6.4.1], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.1.32 3.6.1.32] Known structural/functional Site: <scene name='pdbsite=AC1:Ca+Binding+Site+For+Chain+C'>AC1</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BL0 OCA]. |
==Reference== | ==Reference== | ||
| Line 24: | Line 24: | ||
[[Category: slime mould]] | [[Category: slime mould]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb 3 10:25:19 2008'' |
Revision as of 08:25, 3 February 2008
|
PHYSARUM POLYCEPHALUM MYOSIN II REGULATORY DOMAIN
Overview
We have previously identified a single inhibitory Ca2+-binding site in the, first EF-hand of the essential light chain of Physarum conventional myosin, (Farkas, L., Malnasi-Csizmadia, A., Nakamura, A., Kohama, K., and Nyitray, L. (2003) J. Biol. Chem. 278, 27399-27405). As a general rule, conformation of the EF-hand-containing domains in the calmodulin family is, "closed" in the absence and "open" in the presence of bound cations; a, notable exception is the unusual Ca2+-bound closed domain in the essential, light chain of the Ca2+-activated scallop muscle myosin. Here we have, reported the 1.8 A resolution structure of the regulatory domain (RD) of, Physarum myosin II in which Ca2+ is bound to a canonical EF-hand that is, also in a closed state. The 12th position of the EF-hand loop, which, normally provides a bidentate ligand for Ca2+ in the open state, is too, far in the structure to participate in coordination of the ion. The, structure includes a second Ca2+ that only mediates crystal contacts. To, reveal the mechanism behind the regulatory effect of Ca2+, we compared, conformational flexibilities of the liganded and unliganded RD. Our, working hypothesis, i.e. the modulatory effect of Ca2+ on conformational, flexibility of RD, is in line with the observed suppression of, hydrogen-deuterium exchange rate in the Ca2+-bound form, as well as with, results of molecular dynamics calculations. Based on this evidence, we, concluded that Ca2+-induced change in structural dynamics of RD is a major, factor in Ca2+-mediated regulation of Physarum myosin II activity.
About this Structure
2BL0 is a Protein complex structure of sequences from Physarum polycephalum with as ligand. Active as Transferred entry: 3.6.4.1, with EC number 3.6.1.32 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Structural evidence for non-canonical binding of Ca2+ to a canonical EF-hand of a conventional myosin., Debreczeni JE, Farkas L, Harmat V, Hetenyi C, Hajdu I, Zavodszky P, Kohama K, Nyitray L, J Biol Chem. 2005 Dec 16;280(50):41458-64. Epub 2005 Oct 13. PMID:16227209
Page seeded by OCA on Sun Feb 3 10:25:19 2008
