1F4J: Structure Of Tetragonal Crystals Of Human Erythrocyte Catalase

The structure of catalase from human erythrocytes (HEC) was determined in tetragonal crystals of space group I4(1) by molecular-replacement methods, using the orthorhombic crystal structure as a search model. It was then refined in a unit cell of dimensions a = b = 203.6 and c = 144.6 A, yielding R and R(free) of 0.196 and 0.244, respectively, for all data at 2.4 A resolution. A major difference of the HEC structure in the tetragonal crystal compared with the orthorhombic structure was the omission of a 20-residue N-terminal segment corresponding to the first exon of the human catalase gene. The overall structures were otherwise identical in both crystal forms. The NADPH-binding sites were empty in all four subunits and bound water molecules were observed at the active sites. The structure of the C-terminal segment, which corresponds to the last exon, remained undetermined. The tetragonal crystals showed a pseudo-4(1)22 symmetry in molecular packing. Two similar types of lattice contact interfaces between the HEC tetramers were observed; they were related by the pseudo-dyad axes.
PDB ID: 1F4JDownload
MMDB ID: 13640
PDB Deposition Date: 2000/6/7
Updated in MMDB: 2007/11
Experimental Method:
x-ray diffraction
Resolution: 2.4  Å
Source Organism:
Similar Structures:
Biological Unit for 1F4J: tetrameric; determined by author and by software (PISA)
Molecular Components in 1F4J
Label Count Molecule
Proteins (4 molecules)
Catalase(Gene symbol: CAT)
Molecule annotation
Chemicals (4 molecules)
* Click molecule labels to explore molecular sequence information.

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