Ergodic pumping: A mechanism to drive biomolecular conformation changes

MacKay, Robert S.; Mackay, David

doi:10.1016/j.physd.2006.02.006

Cited by 10 publications

(6 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It cannot be via heat because this would be inefficient. The confined phosphate must more directly exert a force on the NBD ( MacKay and MacKay, 2006 ). Likewise, it is not known when or the order in which the hydrolysis products unbind from the NBD.…”

Section: Discussionmentioning

confidence: 99%

Insights into How Nucleotide-Binding Domains Power ABC Transport

Newstead¹,

Fowler²,

Bilton³

et al. 2009

Structure

View full text Add to dashboard Cite

SummaryThe mechanism by which nucleotide-binding domains (NBDs) of ABC transporters power the transport of substrates across cell membranes is currently unclear. Here we report the crystal structure of an NBD, FbpC, from the Neisseria gonorrhoeae ferric iron uptake transporter with an unusual and substantial domain swap in the C-terminal regulatory domain. This entanglement suggests that FbpC is unable to open to the same extent as the homologous protein MalK. Using molecular dynamics we demonstrate that this is not the case: both NBDs open rapidly once ATP is removed. We conclude from this result that the closed structures of FbpC and MalK have higher free energies than their respective open states. This result has important implications for our understanding of the mechanism of power generation in ABC transporters, because the unwinding of this free energy ensures that the opening of these two NBDs is also powered.

show abstract

Section: Discussionmentioning

confidence: 99%

Insights into How Nucleotide-Binding Domains Power ABC Transport

Newstead¹,

Fowler²,

Bilton³

et al. 2009

Structure

View full text Add to dashboard Cite

show abstract

“…In particular it was pointed out that the pressure of a single molecule (e.g. a phosphate ion) expanding a trap could supply part of the energy required to perform the power stroke [ 46 ]. Although plausible these mechanisms are highly hypothetical and bears no relationship with our studies on the macromolecular osmotic pressure of the contractile proteins.…”

Section: Discussionmentioning

confidence: 99%

Water and Muscle Contraction

Grazi

2008

IJMS

View full text Add to dashboard Cite

Abstract:The interaction between water and the protein of the contractile machinery as well as the tendency of these proteins to form geometrically ordered structures provide a link between water and muscle contraction. Protein osmotic pressure is strictly related to the chemical potential of the contractile proteins, to the stiffness of muscle structures and to the viscosity of the sliding of the thin over the thick filaments. Muscle power output and the steady rate of contraction are linked by modulating a single parameter, a viscosity coefficient. Muscle operation is characterized by working strokes of much shorter length and much quicker than in the classical model. As a consequence the force delivered and the stiffness attained by attached cross-bridges is much larger than usually believed.

show abstract

“…This is the appropriate way to view a biomolecular system in thermal equilibrium but out of chemical equilibrium. Indeed such problems motivated the present paper [20].…”

Section: Kinetics Out Of Chemical Equilibriummentioning

confidence: 94%