Carregant...
Fitxers
Tipus de document
ArticleVersió
Versió acceptadaData de publicació
Tots els drets reservats
Si us plau utilitzeu sempre aquest identificador per citar o enllaçar aquest document: https://hdl.handle.net/2445/108975
Effect of crowding by dextrans on the hydrolysis of N-Succinyl-L-phenyl-Ala-p-nitroanilide catalyzed by α-chymotrypsin
Títol de la revista
Director/Tutor
ISSN de la revista
Títol del volum
Recurs relacionat
Resum
Traditionally, studies on the diffusion-controlled reaction of biological macromolecules have been carried out in dilute solutions (in vitro). However, in an intracellular environment (in vivo), there is a high concentration of macromolecules, which results in nonspecific interactions (macromolecular crowding). This affects the kinetics and thermodynamics of the reactions that occur in these systems. In this paper, we study the crowding effect of large macromolecules on the reaction rates of the hydrolysis of N-succinyl-L-phenyl-Ala-p-nitroanilide catalyzed by R-chymo- trypsin, by adding dextrans of various molecular weights to the reaction solutions. The results indicate that the volume occupied by the crowding agent, but not its size, plays an important role in the rate of this reaction. A vmax decay and a Km increase were obtained when the dextran concentration in the sample was increased. The increase in Km can be attributed to the slowing of protein diffusion, due to the presence of crowding. Whereas the decrease in vmax could be explained by the effect of mixed inhibition by product, which is enhanced in crowded media. As far as we know, this is the first reported experiment on the crowding effect in an enzymatic reaction with a mixed inhibition by product.
Matèries
Matèries (anglès)
Citació
Citació
PASTOR, Isabel, VILASECA I FONT, Eudald, MADURGA DÍEZ, Sergio, GARCÉS, Josep lluís, CASCANTE I SERRATOSA, Marta, MAS I PUJADAS, Francesc. Effect of crowding by dextrans on the hydrolysis of N-Succinyl-L-phenyl-Ala-p-nitroanilide catalyzed by α-chymotrypsin. _Journal of Physical Chemistry B_. 2011. Vol. 115, núm. 5, pàgs. 1115-1121. [consulta: 25 de gener de 2026]. ISSN: 1520-6106. [Disponible a: https://hdl.handle.net/2445/108975]