2oh8
From Proteopedia
| Line 4: | Line 4: | ||
|PDB= 2oh8 |SIZE=350|CAPTION= <scene name='initialview01'>2oh8</scene>, resolution 1.80Å | |PDB= 2oh8 |SIZE=350|CAPTION= <scene name='initialview01'>2oh8</scene>, resolution 1.80Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= MB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9755 Physeter catodon]) | |GENE= MB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9755 Physeter catodon]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[2oh9|2OH9]], [[2oha|2OHA]], [[2ohb|2OHB]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2oh8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2oh8 OCA], [http://www.ebi.ac.uk/pdbsum/2oh8 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2oh8 RCSB]</span> | ||
}} | }} | ||
| Line 25: | Line 28: | ||
[[Category: Olson, J S.]] | [[Category: Olson, J S.]] | ||
[[Category: Soman, J.]] | [[Category: Soman, J.]] | ||
| - | [[Category: HEM]] | ||
| - | [[Category: SO4]] | ||
[[Category: ligand entry and exit pathway]] | [[Category: ligand entry and exit pathway]] | ||
[[Category: myoglobin]] | [[Category: myoglobin]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 04:17:47 2008'' |
Revision as of 01:17, 31 March 2008
| |||||||
| , resolution 1.80Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | MB (Physeter catodon) | ||||||
| Related: | 2OH9, 2OHA, 2OHB
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Myoglobin cavity mutant I28W
Overview
The pathways for ligand entry and exit in myoglobin have now been well established by a wide variety of experimental results, including pico- to nano- to microsecond transient absorbance measurements and time-resolved X-ray crystallographic measurements. Trp insertions have been used to block, one at a time, the three major cavities occupied by photodissociated ligands. In this work, we review the effects of the L29(B10)W mutation, which places a large indole ring in the initial 'docking site' for photodissociated ligands. Then, the effects of blocking the Xe4 site with I28W, V68W, and I107W mutations and the Xe1 cavity with L89W, L104W, and F138W mutations are described. The structures of four of these mutants are shown for the first time (Trp28, Trp68, Trp107, and Trp 138 sperm whale metMb). All available results support a 'side path' mechanism in which ligands move into and out of myoglobin by outward rotation of the HisE7 side chain, but after entry can migrate into internal cavities, including the distal Xe4 and proximal Xe1 binding sites. The distal cavities act like the pocket of a baseball glove, catching the ligand and holding it long enough for the histidine gate to close and facilitate internal coordination with the heme iron atom. The physiological role of the proximal Xe1 site is less clear because changes in the size of this cavity have minimal effects on overall O(2) binding parameters.
About this Structure
2OH8 is a Single protein structure of sequence from Physeter catodon. Full crystallographic information is available from OCA.
Reference
Ligand pathways in myoglobin: a review of Trp cavity mutations., Olson JS, Soman J, Phillips GN Jr, IUBMB Life. 2007 Aug-Sep;59(8-9):552-62. PMID:17701550
Page seeded by OCA on Mon Mar 31 04:17:47 2008
