Linked Life Data

9107144

Source:http://linkedlifedata.com/resource/pubmed/id/9107144

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1997-5-8
pubmed:abstractText
We examined the structural stabilities after heat treatment of 22 mutants of rat prolactin (rPRL) with amino acid replacements at 15 different positions and recombinant wild-type rPRL (WT-PRL) as part of our series of studies on site-directed mutagenesis of rPRL. When WT-PRL at low concentrations (0.1-10 ng/ml) was heated at 100 degrees C for 20 min, it lost its Nb2 proliferation activity, whereas at high concentrations (above 1 microgram/ml), its activity remained. Temperature-dependent loss of the proliferation activity of 10 ng/ml WT-PRL after heat treatment for 5 min was observed. Next, we examined the proliferation activities of the 22 mutants heated at 60 and 70 degrees C for 5 min. After treatment at 60 degrees C, all the mutants retained their initial proliferation activities, whereas treatment at 70 degrees C reduced their activities to about 63%, except for one in which glutamic acid at position 118 was replaced by lysine (E118K), suggesting that the mutations did not induce structural instability. The mutant E118K retained 84% of its initial activity after treatment at 70 degrees C, significantly (P < 0.01) higher than the WT-PRL value. The temperature-dependency profile of the Nb2 proliferation activity of E118K also showed it had significantly increased thermo-stability. Meanwhile another mutant (E118Q) at the same residue showed no increased thermo-stability, suggesting that changing a negative charge (E) to a positive one (K) at position 118 induces ionic bond formation with a neighboring negative charge, resulting in thermostabilization of the structure of PRL.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
B
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0289-0003
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
915-9
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Increased thermo-stability of rat prolactin after replacing glutamic acid at position 118 by lysine.
pubmed:affiliation
Biosignal Research Center, Gunma University, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't