Chapter 14, Problem 10P

A.

Summary Introduction

To explain: Why the actin filaments revolve in steps of ATP synthesis with pause in between and what does the rotation correspond to in terms of the α₃β₃ γ complex.

Concept introduction:

The total process of ATP synthesis is complex membrane-embedded enzyme that looks like a rounded structure with complete rotation.  The rounded structure of enzyme is regarded as the F₁ subunit that protrudes into the mitochondrial matrix and contains the catalytic activity of the enzyme synthase. This subunit contains various polypeptide chains.  The α and β subunit of the polypeptide chain, make up the bulk of the F₁ arranged alternatively in the rotational structure. The α and β subunit bind nucleotides but only the β subunits participate directly in catalysis functioning. The γ subunit breaks the symmetric position of the α₃β₃ hexamer, in each of the β subunits is different by virtue of its interaction with a distinct face of γ.

B.

Summary Introduction

To explain: In this normal mode of operation inside the cell, total how many number of ATP molecules synthesize for each complete 360° rotation of γ subunit.

Concept introduction:

The total process of ATP synthesis is complex membrane-embedded enzyme that looks like a rounded structure with complete rotation.  The rounded structure of enzyme is regarded as the F₁ subunit that protrudes into the mitochondrial matrix and contains the catalytic activity of the enzyme synthase. This subunit contains various polypeptide chains.  The α and β subunit of the polypeptide chain, make up the bulk of the F₁ arranged alternatively in the rotational structure. The α and β subunit bind nucleotides but only the β subunits participate directly in catalysis functioning. The γ subunit breaks the symmetric position of the α₃β₃ hexamer, in each of the β subunits is different by virtue of its interaction with a distinct face of γ.