Bacterioferritin
Encyclopedia
Bacterioferritin is an oligomeric protein
containing both a binuclear iron centre and haem b. The tertiary
and quaternary structure
of BFR is very similar to that of ferritin
. The physiological functions of BFR, which may be other than just iron uptake, are not clear. BFR forms a roughly spherical, hollow shell from 24 identical subunits, incorporating 12 haem groups. Iron is stored as a hydrated ferric oxide mineral in its central cavity (about 80 Å diameter). The overall complex has cubic (432) symmetry. Each subunit includes a binuclear metalbinding site (the diiron site) linking together the four major helices of the subunit, which has been identified as the ferroxidase active site.
BFR from Pseudomonas aeruginosa
, unlike other BFRs, is found to contain two subunit types, which differ considerably in their amino acid sequences. A similar hetero-assembly is seen in the ferritins of higher eukaryotes.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
containing both a binuclear iron centre and haem b. The tertiary
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...
and quaternary structure
Quaternary structure
In biochemistry, quaternary structure is the arrangement of multiple folded protein or coiling protein molecules in a multi-subunit complex.-Description and examples:...
of BFR is very similar to that of ferritin
Ferritin
Ferritin is a ubiquitous intracellular protein that stores iron and releases it in a controlled fashion. The amount of ferritin stored reflects the amount of iron stored. The protein is produced by almost all living organisms, including bacteria, algae and higher plants, and animals...
. The physiological functions of BFR, which may be other than just iron uptake, are not clear. BFR forms a roughly spherical, hollow shell from 24 identical subunits, incorporating 12 haem groups. Iron is stored as a hydrated ferric oxide mineral in its central cavity (about 80 Å diameter). The overall complex has cubic (432) symmetry. Each subunit includes a binuclear metalbinding site (the diiron site) linking together the four major helices of the subunit, which has been identified as the ferroxidase active site.
BFR from Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
, unlike other BFRs, is found to contain two subunit types, which differ considerably in their amino acid sequences. A similar hetero-assembly is seen in the ferritins of higher eukaryotes.