Structural Determinants in the Interaction of Shaker Inactivating Peptide and a Ca2+-Activated K+ Channel
Author
dc.contributor.author
Toro, Ligia
Author
dc.contributor.author
Ottolia, Michela
Author
dc.contributor.author
Stefani, Enrico
Author
dc.contributor.author
Latorre, Ramón
Admission date
dc.date.accessioned
2019-01-29T15:49:53Z
Available date
dc.date.available
2019-01-29T15:49:53Z
Publication date
dc.date.issued
1994
Cita de ítem
dc.identifier.citation
Biochemistry 1994, 33, 7220-7228
Identifier
dc.identifier.issn
15204995
Identifier
dc.identifier.issn
00062960
Identifier
dc.identifier.other
10.1021/bi00189a026
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/162476
Abstract
dc.description.abstract
Shaker B inactivating peptide (BP) binds to its receptor in maxi Kca channels obstructing the flow of ions through them. The interaction between Kca channels and BP mutants, with different net charge and hydrophobicity, revealed several structural features of the Kca channel internal mouth. Increasing BP net positive charge or decreasing the internal milieu ionic strength increased the affinity and rate of association, while increasing hydrophobicity augmented blocking times and had limited or no effect on on-rates. These results uncover (a) the presence of negative charges in or near the BP receptor and (b) the existence of a hydrophobic contact surface in the internal channel vestibule that is a structural constituent of the BP receptor in maxi Kca channels.