pH delta very low

Edge evidence

• very limited pH-homeostasis flexibility produces pH delta very low METPO:2000202

  Very limited pH-homeostasis flexibility yields a narrow pH-delta breadth.

  • DOI:10.1038/nrmicro2549 pH homeostasis Supports very limited pH-homeostasis flexibility as the basis of stenotopic breadth.
• pH delta very low is a pH delta rdfs:subClassOf

  pH delta very low is a quantitative bin of the pH-delta phenotype.

  • DOI:10.1016/j.tim.2007.02.005 proton motive force Supports a very narrow breadth as a value within the pH-delta distribution.
• external pH stress alters PMF partitioning (delta-pH / delta-psi)

  External pH stress alters partitioning of the proton motive force between delta-pH and delta-psi.

  • DOI:10.1038/nrmicro2549 The two PMF components, delta-psi and delta-pH, are adjustable according to pH demand and can even reverse orientation under strong pH stress; broad foundational pH-homeostasis edge.
• constitutive pH-homeostasis machinery expression imposes energetic cost on energetic cost on growth near neutral pH

  Constitutive expression of pH-homeostatic machinery imposes an energetic cost impairing growth near neutral pH.

  • DOI:10.1038/nrmicro2549 Extremophiles often express major pH homeostatic mechanisms constitutively; this preparedness imposes an energetic cost and can impair growth at near-neutral pH (inferred breadth-constraint mechanism).
• Na+/H+ antiporter activity enables alkaline pH homeostasis RO:0002327

  Na+/H+ antiporter activity enables alkaline pH homeostasis.

  • DOI:10.1038/nrmicro2549 Na+/H+ antiport (notably the hetero-oligomeric Mrp system) is a major, causally important strategy for alkaline pH homeostasis.
• F1Fo-ATPase hydrolytic proton pumping promotes acid stress survival RO:0002213

  Hydrolytic F1Fo-ATPase proton pumping promotes acid stress survival.

  • DOI:10.1038/nrmicro2549 Hydrolytic F1Fo-ATPase activity can be increased for ATP-dependent H+ extrusion under acid stress; strong acid-side homeostasis mechanism.
• glutamate decarboxylase GadB + GABA/glutamate antiporter consumes cytoplasmic proton consumption biolink:consumes

  Glutamate decarboxylase GadB coupled with a GABA/glutamate antiporter consumes cytoplasmic protons.

  • DOI:10.1038/nrmicro2549 Amino acid decarboxylases like GadB with its antiporter coupling; canonical acid-resistance mechanism consuming cytoplasmic protons.