NaCl delta

Edge evidence

• osmoadaptive flexibility enables euryhaline physiology RO:0002327

  Osmoadaptive flexibility enables euryhaline growth.

  • DOI:10.1186/1746-1448-4-2 cope with the high salt concentrations Supports osmoadaptive flexibility as the basis of broad-salinity growth.
• euryhaline physiology produces tolerance breadth METPO:2000202

  Euryhaline physiology produces a wide growth-supporting NaCl range.

  • DOI:10.1093/femsre/fuy009 salinity range Supports the link between osmoadaptive physiology and tolerance breadth.
• tolerance breadth manifests as NaCl delta METPO:2007400

  The breadth between minimum and maximum growth-supporting NaCl manifests the NaCl-delta phenotype.

  • DOI:10.1093/femsre/fuy009 salinity range Supports the trait endpoint.
• compatible solute accumulation enables response to osmotic stress RO:0002327

  Accumulation of neutral compatible solutes enables osmoadaptation and broader salt-supported growth.

  • DOI:10.1128/MMBR.00181-23 To avoid K+-induced cytotoxicity and high ionic strength, cells accumulate or synthesize neutral compatible solutes (glycine betaine, trehalose, ectoine, proline).
• hyperosmotic upshift causes potassium ion uptake biolink:causes

  Hyperosmotic upshift triggers rapid K+ import as an early osmoadaptive response.

  • DOI:10.1128/MMBR.00181-23 Cells import large amounts of K+ during osmotic upshift; potassium is the principal cytoplasmic cation.
• potassium ion uptake contributes to response to osmotic stress RO:0002326

  K+ accumulation is a core early osmoadaptive response to increased NaCl.

  • DOI:10.1128/MMBR.00181-23 Cytoplasmic K+ levels ~250 mM (E. coli) to ~500 mM (C. glutamicum, L. lactis) accumulate as a core osmoadaptive response.
• salt-out strategy uses compatible solute accumulation

  The salt-out strategy relies on accumulation of organic compatible solutes.

  • DOI:10.3390/microorganisms12081738 Salt-out excludes Na+ while accumulating organic compatible solutes like sugars, polyalcohols, ectoine, trehalose, glycine-betaine.
• salt-in strategy supports high maximal NaCl tolerance

  The salt-in strategy supports very high maximal salinity tolerance, extending the upper NaCl limit.

  • DOI:10.3390/microorganisms12081738 Salt-out is energetically costly and less suited to saturating salinities; salt-in is favored at very high salt.
• mechanosensitive channels (MscL/MscS) protects against hypoosmotic shock

  Mechanosensitive channels act as safety valves protecting cells against sudden hypoosmotic shocks at the low-salinity end of the range.

  • DOI:10.3390/microorganisms12081738 Mechanosensitive (Msc) channels and compatible-solute efflux systems act as safety valves during sudden hypoosmotic shocks.