3h57 | pdb_00003h57

Myoglobin Cavity Mutant H64LV68N Deoxy form

spinqualitylabelsall models 3h57, resolution 1.70Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3h57 is a 1 chain structure with sequence from Phycd. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: HEM Related: 3h58 Gene: MB (PHYCD) Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum Function [MYG_PHYMC] Serves as a reserve supply of oxygen and facilitates the movement of oxygen within muscles. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Internal water molecules are important to protein structure and function, but positional disorder and low occupancies can obscure their detection by X-ray crystallography. Here, we show that water can be detected within the distal cavities of myoglobin mutants by subtle changes in the absorbance spectrum of pentacoordinate heme, even when the presence of solvent is not readily observed in the corresponding crystal structures. A well-defined, noncoordinated water molecule hydrogen bonded to the distal histidine (His64) is seen within the distal heme pocket in the crystal structure of wild type (wt) deoxymyoglobin. Displacement of this water decreases the rate of ligand entry into wt Mb, and we have shown previously that the entry of this water is readily detected optically after laser photolysis of MbCO complexes. However, for L29F and V68L Mb no discrete positions for solvent molecules are seen in the electron density maps of the crystal structures even though His64 is still present and slow rates of ligand binding indicative of internal water are observed. In contrast, time-resolved perturbations of the visible absorption bands of L29F and V68L deoxyMb generated after laser photolysis detect the entry and significant occupancy of water within the distal pockets of these variants. Thus, the spectral perturbation of pentacoordinate heme offers a potentially robust system for measuring nonspecific hydration of the active sites of heme proteins. Optical detection of disordered water within a protein cavity.,Goldbeck RA, Pillsbury ML, Jensen RA, Mendoza JL, Nguyen RL, Olson JS, Soman J, Kliger DS, Esquerra RM J Am Chem Soc. 2009 Sep 2;131(34):12265-72. PMID:19655795 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Myoglobin

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