Cooperative macromolecular device revealed by meta-analysis of static and time-resolved structures.
Proc Natl Acad Sci U S A
; 109(1): 107-12, 2012 Jan 03.
Article
em En
| MEDLINE
| ID: mdl-22171006
ABSTRACT
Here we present a meta-analysis of a large collection of static structures of a protein in the Protein Data Bank in order to extract the progression of structural events during protein function. We apply this strategy to the homodimeric hemoglobin HbI from Scapharca inaequivalvis. We derive a simple dynamic model describing how binding of the first ligand in one of the two chemically identical subunits facilitates a second binding event in the other partner subunit. The results of our ultrafast time-resolved crystallographic studies support this model. We demonstrate that HbI functions like a homodimeric mechanical device, such as pliers or scissors. Ligand-induced motion originating in one subunit is transmitted to the other via conserved pivot points, where the E and F' helices from two partner subunits are "bolted" together to form a stable dimer interface permitting slight relative rotation but preventing sliding.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Hemoglobinas
/
Substâncias Macromoleculares
Tipo de estudo:
Systematic_reviews
Limite:
Animals
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Estados Unidos