Response Of γ-aminobutyric Acid To External Acidification

GABA increases rapidly in cells at low pH, and this accumulation of GABA also exists in microorganisms and animals. In plants, the intracellular H+ increases in acidic pH, which induces an increase in intracellular GABA content. The synthesis of GABA consumes H+, which alleviates intracellular acidification. This rapid response mechanism also exists in microorganisms, which increases the expression of proton respiratory chain complexes and promotes ATP synthesis while producing GABA. And up-regulated the activity of F1F0-ATP hydrolase to promote the ATP-dependent H+ excretion process under acidic conditions. In animals, cells also expel GABA and glutamate to alter the pH of the extracellular environment. More importantly, GABA is a zwitterion under physiological conditions and thus plays a role in acid-base regulation.