Interaction of alpha-agglutinin and a-agglutinin, Saccharomyces cerevisiae sexual cell adhesion molecules.
J Bacteriol
; 183(9): 2874-80, 2001 May.
Article
en En
| MEDLINE
| ID: mdl-11292808
alpha-Agglutinin and a-agglutinin are complementary cell adhesion glycoproteins active during mating in the yeast Saccharomyces cerevisiae. They bind with high affinity and high specificity: cells of opposite mating types are irreversibly bound by a few pairs of agglutinins. Equilibrium and surface plasmon resonance kinetic analyses showed that the purified binding region of alpha-agglutinin interacted similarly with purified a-agglutinin and with a-agglutinin expressed on cell surfaces. At 20 degrees C, the K(D) for the interaction was 2 x 10(-9) to 5 x 10(-9) M. This high affinity was a result of a very low dissociation rate ( approximately 2.6 x 10(-4) s(-1)) coupled with a low association rate (= 5 x 10(4) M(-1) s(-1)). Circular-dichroism spectroscopy showed that binding of the proteins was accompanied by measurable changes in secondary structure. Furthermore, when binding was assessed at 10 degrees C, the association kinetics were sigmoidal, with a very low initial rate. An induced-fit model of binding with substantial apposition of hydrophobic surfaces on the two ligands can explain the observed affinity, kinetics, and specificity and the conformational effects of the binding reaction.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Péptidos
/
Saccharomyces cerevisiae
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Proteínas Fúngicas
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Moléculas de Adhesión Celular
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Proteínas de Saccharomyces cerevisiae
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Aglutininas
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
J Bacteriol
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos