Linked Life Data

2185972

Source:http://linkedlifedata.com/resource/pubmed/id/2185972

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1990-6-12
pubmed:abstractText
Four distinct macromolecular antifreezes have been isolated and characterized from different marine fish. These include the glycoprotein antifreezes (Mr 2.5-33 K), which are made up of a repeating tripeptide (Ala-Ala-Thr)n with a disaccharide attached to the threonyl residues, and three antifreeze protein (AFP) types. Type I is an alanine-rich, amphiphilic, alpha-helix (Mr 3-5 K); type II is a larger protein (Mr 14 K) with a high content of reverse turns and five disulfide bridges; and type III is intermediate in size (Mr 6-7 K) with no distinguishing features of secondary structure or amino acid composition. Despite their marked structural differences, all four antifreeze types appear to function in the same way by binding to the prism faces of ice crystals and inhibiting growth along the a-axes. It is suggested that type I AFP binds preferentially to the prism faces as a result of interactions between the helix macrodipole and the dipoles on the water molecules in the ice lattice. Binding is stabilized by hydrogen bonding, and the amphiphilic character of the helix results in the hydrophobic phase of the helix being exposed to the solvent. When the solution temperature is lowered further, ice crystal growth occurs primarily on the uncoated, unordered basal plane resulting in bipyramidal-shaped crystals. The structural features of type I AFP that could contribute to this mechanism of action are reviewed. Current challenges lie in solving the other antifreeze structures and interpreting them in light of what appears to be a common mechanism of action.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0892-6638
pubmed:author
pubmed:issnType
Print
pubmed:volume
4
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2460-8
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Biochemistry of fish antifreeze proteins.
pubmed:affiliation
Department of Biochemistry, Queen's University, Kingston, Ontario, Canada.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't