2aa1
From Proteopedia
(New page: 200px<br /> <applet load="2aa1" size="450" color="white" frame="true" align="right" spinBox="true" caption="2aa1, resolution 1.80Å" /> '''Crystal structure o...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:2aa1.gif|left|200px]]<br /> | + | [[Image:2aa1.gif|left|200px]]<br /><applet load="2aa1" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="2aa1" size=" | + | |
caption="2aa1, resolution 1.80Å" /> | caption="2aa1, resolution 1.80Å" /> | ||
'''Crystal structure of the cathodic hemoglobin isolated from the Antarctic fish Trematomus Newnesi'''<br /> | '''Crystal structure of the cathodic hemoglobin isolated from the Antarctic fish Trematomus Newnesi'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The cathodic hemoglobin component of the Antarctic fish Trematomus newnesi | + | The cathodic hemoglobin component of the Antarctic fish Trematomus newnesi (HbCTn) is a Root-effect protein. The interpretation of its functional properties in relation to its sequence is puzzling. Indeed, HbCTn sequence is characterized by an extremely low histidyl content, and in particular by the lack of His146beta and His69beta, which are believed to be important in Bohr and Root effects, respectively. Furthermore, previous analyses suggested that the local environment of Asp95alpha, Asp99beta, and Asp101beta should not be appropriate for the formation of Asp-Asp interactions, which are important for the Root effect. Here, we report the high-resolution crystal structure of the deoxy form of HbCTn. Our data provide a structural interpretation for the very low oxygen affinity of the protein and insights into the structural determinants of the Root effect protein. The structure demonstrates that the presence of Ile41alpha and Ser97alpha at the alpha1beta2 interface does not prevent the formation of the inter-Asp interactions in HbCTn, as previous studies had suggested. The present data indicate that the hydrogen bond formed between Asp95alpha and Asp101beta, which is stabilized by Asp99beta, is per se sufficient to generate the Root effect, and it is the minimal structural requirement needed for the design of Root-effect Hbs. |
==About this Structure== | ==About this Structure== | ||
| - | 2AA1 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Trematomus_newnesi Trematomus newnesi] with ACE and HEM as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 2AA1 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Trematomus_newnesi Trematomus newnesi] with <scene name='pdbligand=ACE:'>ACE</scene> and <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AA1 OCA]. |
==Reference== | ==Reference== | ||
| Line 15: | Line 14: | ||
[[Category: Trematomus newnesi]] | [[Category: Trematomus newnesi]] | ||
[[Category: Bonomi, G.]] | [[Category: Bonomi, G.]] | ||
| - | [[Category: Lubrano, M | + | [[Category: Lubrano, M C.]] |
[[Category: Mazzarella, L.]] | [[Category: Mazzarella, L.]] | ||
[[Category: Merlino, A.]] | [[Category: Merlino, A.]] | ||
| - | [[Category: Prisco, G | + | [[Category: Prisco, G Di.]] |
[[Category: Riccio, A.]] | [[Category: Riccio, A.]] | ||
[[Category: Verde, C.]] | [[Category: Verde, C.]] | ||
| Line 30: | Line 29: | ||
[[Category: root effect]] | [[Category: root effect]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:25:21 2008'' |
Revision as of 14:25, 21 February 2008
|
Crystal structure of the cathodic hemoglobin isolated from the Antarctic fish Trematomus Newnesi
Overview
The cathodic hemoglobin component of the Antarctic fish Trematomus newnesi (HbCTn) is a Root-effect protein. The interpretation of its functional properties in relation to its sequence is puzzling. Indeed, HbCTn sequence is characterized by an extremely low histidyl content, and in particular by the lack of His146beta and His69beta, which are believed to be important in Bohr and Root effects, respectively. Furthermore, previous analyses suggested that the local environment of Asp95alpha, Asp99beta, and Asp101beta should not be appropriate for the formation of Asp-Asp interactions, which are important for the Root effect. Here, we report the high-resolution crystal structure of the deoxy form of HbCTn. Our data provide a structural interpretation for the very low oxygen affinity of the protein and insights into the structural determinants of the Root effect protein. The structure demonstrates that the presence of Ile41alpha and Ser97alpha at the alpha1beta2 interface does not prevent the formation of the inter-Asp interactions in HbCTn, as previous studies had suggested. The present data indicate that the hydrogen bond formed between Asp95alpha and Asp101beta, which is stabilized by Asp99beta, is per se sufficient to generate the Root effect, and it is the minimal structural requirement needed for the design of Root-effect Hbs.
About this Structure
2AA1 is a Protein complex structure of sequences from Trematomus newnesi with and as ligands. Full crystallographic information is available from OCA.
Reference
Minimal structural requirements for root effect: crystal structure of the cathodic hemoglobin isolated from the antarctic fish Trematomus newnesi., Mazzarella L, Bonomi G, Lubrano MC, Merlino A, Riccio A, Vergara A, Vitagliano L, Verde C, di Prisco G, Proteins. 2006 Feb 1;62(2):316-21. PMID:16299734
Page seeded by OCA on Thu Feb 21 16:25:21 2008
