Linked Life Data

9350994

Source:http://linkedlifedata.com/resource/pubmed/id/9350994

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-11-28
pubmed:abstractText
Plasminogen activator inhibitor 1 (PAI-1), a member of the serpins, has a unique conformational flexibility. A typical characteristic is its intrinsic lability resulting in the conversion of the active conformation to a latent conformation. In the present study, we have evaluated the effect of substitution of positively charged residues located at the turn connecting strand s4C with strand s3C, either with negatively charged or with neutral residues, on the functional stability of PAI-1. The following mutants were constructed, purified and characterized in comparison to wild-type (wt) PAI-1: PAI-1-R186E,R187E (Arg186--> Glu and Arg187--> Glu), PAI-1-H190E,K191E (His190--> Glu and Lys191--> Glu) and PAI-1-H190L,K191L (His190--> Leu and Lys191--> Leu). In contrast to wtPAI-1 the mutants exhibited no inhibitory activity. Whereas latent wtPAI-1 can be reactivated (up to a specific activity of 78+/-19%) by treatment with guanidinium chloride, a similar treatment applied to these mutants resulted in a significant but relatively small increase of specific activity (i.e. to 14%). Evaluation of the functional stability (at 37 degrees C, pH 5.5, 1 M NaCl revealed a strongly decreased functional stability compared to wtPAI-1 (i.e. 3-9 h for the mutants vs. > 24 h for wtPAI-1). Further characterization by heat denaturation studies and plasmin susceptibility confirmed that removal or reversal of the positive charge on the turn connecting s4C with s3C results in PAI-1 mutants with a highly accelerated conversion of active to latent forms. We can therefore conclude that the pronounced positive charge in the turn connecting s4C with s3C is of the highest importance for the functional stability of PAI-1.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-5793
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
415
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
192-5
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Identification of positively charged residues contributing to the stability of plasminogen activator inhibitor 1.
pubmed:affiliation
Laboratory for Pharmaceutical Biology and Phytopharmacology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't