ATPC Antibody

Introduction

The ATPC antibody targets the gamma subunit (AtpC) of ATP synthase, a critical enzyme in cellular energy production. This antibody is primarily used in plant biology and chloroplast research to study ATP synthase structure, function, and regulation. ATP synthase is responsible for synthesizing adenosine triphosphate (ATP) using a proton gradient across membranes, with the gamma subunit playing a pivotal role in regulating enzyme activity and proton flow .

Molecular Composition

• Subunit Architecture: ATP synthase’s gamma subunit (AtpC) is part of the CF$_1$ catalytic core in chloroplasts. It consists of conserved domains critical for rotational catalysis during ATP synthesis .

• Molecular Weight:

  Species	Predicted (kDa)	Observed (kDa)
  Chlamydomonas reinhardtii	35.3	42
  Spinacia oleracea	35.6	38
  Arabidopsis thaliana	35–38	38–42
  Data derived from SDS-PAGE and immunoblotting .

Functional Role

• Proton Transport: Facilitates proton movement through the CF$_0$ channel, driving ATP synthesis .

• Regulation: Modulates ATPase activity via conformational changes in response to the proton gradient .

Immunogen and Specificity

• Immunogen: Synthetic peptides corresponding to residues 46–76 (N-terminal) of Arabidopsis AtpC1/C2 and Chlamydomonas AtpC .

• Cross-Reactivity:

  Confirmed Reactivity	Predicted Reactivity	Non-Reactive Species
  Arabidopsis thaliana	Glycine max, Vitis vinifera	Mammalian cells
  Chlamydomonas reinhardtii	Cyanobacteria	Human, mouse
  Specificity data from epitope mapping and validation .

Applications

• Western Blotting: Used at dilutions of 1:10,000 for detecting AtpC in chloroplast extracts .

• Research Findings:

  • Antibody reactivity varies between plant species due to differences in subunit gamma’s apparent molecular weight (e.g., 42 kDa in Chlamydomonas vs. 38 kDa in spinach) .

  • Critical for studies on ATP synthase assembly defects in Arabidopsis mutants .

Validation Metrics

• Sensitivity: Detects AtpC at concentrations as low as 0.1 µg/mL in plant extracts .

• Batch Variability: Polyclonal nature may lead to minor lot-to-lot variability .

Research Advancements and Therapeutic Potential

• Antibody Engineering: Structural proteomics approaches (e.g., hydrogen/deuterium exchange mass spectrometry) have been used to optimize antibody stability and reduce self-association, enhancing pharmacokinetic profiles .

• Targeted Therapy: Engineered antibodies with improved tissue penetration are being explored for in vivo imaging of ATP synthase dynamics in plant-microbe interactions .