Linked Life Data

3207747

Source:http://linkedlifedata.com/resource/pubmed/id/3207747

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-2-21
pubmed:abstractText
In this study we compare the ability of various amino acids to protect small unilamellar vesicles against damage during freeze/thaw. Liposomes were composed of 75% palmitoyloleoyl phosphatidylcholine and 25% phosphatidylserine. Damage to liposomes frozen in liquid nitrogen and thawed at 20 degrees C was assessed by resonance energy transfer. Cryoprotection by numerous amino acids was compared in the presence and absence of 350 mM NaCl. The majority of amino acids with hydrocarbon side chains increased membrane damage during freeze/thaw regardless of the presence of salt. However, amino acids with hydrocarbon side chains of less than three carbons long, e.g. glycine, alanine, and 2-aminobutyric acid, were cryoprotective only in the presence of salt. We suggest that NaCl selectively increases the solubility of such amino acids, allowing them to act as cryoprotectants. In contrast, amino acids with side chains containing charged amine groups were cryoprotective regardless of the presence of salt. The degree of charge on the second amine group is shown to be important for cryoprotection by these molecules. We present evidence that suggests an interaction between the positively charged, second amine group of the amino acid, and the negatively charged phospholipid headgroup.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
946
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
299-306
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Mechanisms of interaction of amino acids with phospholipid bilayers during freezing.
pubmed:affiliation
Department of Zoology, University of California, Davis 95616.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.