…
comment: The repository administrator has not yet configured an RDF license.
primary topic: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis.

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis.
type: AcademicArticle
type: Article
abstract: The role of a prominent surface-exposed loop (residues 88-97) in the alpha domain of streptokinase (SK), in human plasminogen (HPG) activation was explored through its selective mutagenesis and deletion studies. We first made a conformationally constrained derivative of the loop by the substitution of sequences known to possess a strong propensity for beta-turn formation. The mutant so formed (termed SK88-97-Beta Turn), when tested for co-factor activity against substrate HPG, after first forming a 1:1 molar complex with human plasmin (HPN), showed a nearly 6-fold decreased co-factor activity compared to the wild-type, native SK. The major catalytic change was observed to be at the k(cat) level, with relatively minor changes in Km values against HPG. Real-time binary interaction (i.e. the 1:1 complexation between SK, or its mutant/s, with HPG), and ternary complexation studies (i.e. the docking of a substrate HPG molecule into the preformed SK-HPG complex) using Surface Plasmon Resonance were done. These studies revealed minor alterations in binary complex formation but the ternary interactions of the substitution and/or deletion mutants were found to be decreased for full-length HPG compared to that for native SK.HPG. In contrast, their ternary interactions with the isolated five-kringle domain unit of plasminogen (K1-5) showed Kd values comparable to that seen with the native SK.HPG complex. Taking into consideration the overall alterations observed in catalytic levels after site-specific mutagenesis and complete loop deletion of the 88-97 loop, on the one hand, and its known position at the SK-HPG interface in the binary complex, suggests the importance of this loop. The present results suggest that the 88-97 loop of the alpha domain of SK contributes towards catalytic turn-over, even though its individual contribution towards enzyme-substrate affinity per se is minimal.
date: 2008-09
volume: 1784
issue: 9
is part of: Biochimica et biophysica acta
status: peerReviewed
status: published
author list: authors
type: EPrint
type: ArticleEPrint
is part of: repository
has document: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
has version: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
has published: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
has document: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Indexer Terms)
has document: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Image (PNG))
subject: QR Microbiology

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
type: Document

Elsevier Science
type: Organization

Biochimica et biophysica acta
type: Collection
issn: 00063002

Balvinder Singh
type: Person
given name: Balvinder
family name: Singh

Manish Datt
type: Person
given name: Manish
family name: Datt

Girish Sahni
type: Person
given name: Girish
family name: Sahni

Suman Yadav
type: Person
given name: Suman
family name: Yadav

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Indexer Terms)
type: Document
is version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
is volatile version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
is index codes version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Image (PNG))
type: Document
is version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
is volatile version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
islightbox thumbnail version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Image (PNG))
type: Document
is version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
is volatile version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
ispreview thumbnail version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Image (PNG))
type: Document
is version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
is volatile version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
ismedium thumbnail version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)

Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (Image (PNG))
type: Document
is version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
is volatile version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)
issmall thumbnail version of: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis. (PDF)

HTML Summary of #1071 Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis.
format: text/html
primary topic: Role of the 88-97 loop in plasminogen activation by streptokinase probed through site-specific mutagenesis.

QR Microbiology
type: Concept