Linked Life Data

7982945

Source:http://linkedlifedata.com/resource/pubmed/id/7982945

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
1994-12-30
pubmed:abstractText
Ferritins are 24-mer proteins which store and detoxify intracellular iron. Mammalian ferritins are made of two subunit types, the H- and L-chains, with different functional specificity. The H-chain has a metal-binding site (the ferroxidase center) which confers ferroxidase activity to the protein and accelerates iron incorporation. In the L-chain the center is substituted by a salt bridge. We performed several site-directed mutageneses in the L-chain with the aim to construct the center and confer ferroxidase activity to the protein. Most variants were insoluble and did not refold into homopolymers, probably due to electrostatic repulsion introduced by the substitutions. However, they formed hybrids when they were renatured together with the L- or H-chains. The heteropolymers made of 90% L-chain and 10% of an L-variant with all the ligand residues of the H-chain center had 25-30% of the ferroxidase activity of the H-chain homopolymer. This corresponds to the activity of an H/L heteropolymer with 7% H-chain. It is concluded that: (i) it is possible to construct a ferroxidase center in the L-chain with an activity equivalent to that of the H-chain, (ii) the residues of the center interfere with the folding/assembly of the L-, but not of the H-chain, (iii) heteropolymers can be made even between ferritin subunits with large differences of refolding rates.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
30334-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Construction of a ferroxidase center in human ferritin L-chain.
pubmed:affiliation
Department of Biological and Technological Research, San Raffaele Scientific Institute, Milano, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't