temperature range mid3

Edge evidence

• upper-mesophile adaptation enables temperature range mid3 RO:0002327

  Upper-mesophile adaptation enables growth across 30–34 °C.

  • DOI:10.1146/annurev-micro-091313-103612 more unsaturated fatty acids Supports upper-mesophile homeoviscous adaptation as the range mechanism.
• temperature range mid3 is a temperature range rdfs:subClassOf

  Temperature range mid3 is a quantitative bin of the temperature-range phenotype.

  • DOI:10.1016/s0300-9629(97)00003-0 adapted to environments of high temperature Supports the 30–34 °C range as a value within the temperature-range distribution.
• membrane order / fluidity state drives DesK kinase-dominant state

  Increased membrane order (reduced fluidity) drives DesK to a kinase-dominant state; membrane physical state is the proximate signal.

  • DOI:10.1128/mmbr.00069-23 increased membrane order (reduced fluidity) drives DesK to a kinase-dominant state
• DesK phosphorylates DesR

  Core two-component signaling step linking membrane physical state to transcriptional response.

  • DOI:10.1128/spectrum.03925-23 DesK autophosphorylates (His188) and phosphorylates DesR
• phosphorylated DesR activates transcription of des (acyl-lipid desaturase)

  DesR-P tetramerizes, binds the des promoter and induces lipid desaturation to restore membrane fluidity.

  • DOI:10.1128/spectrum.03925-23 P-DesR tetramerizes, binds Pdes, and activates des expression
• des (acyl-lipid desaturase) introduces double bonds into membrane fatty acyl chains

  Des-mediated unsaturation fluidizes the membrane and reduces bilayer thickness.

  • DOI:10.1128/spectrum.03925-23 Des introduces double bonds into fatty acyl chains, fluidizing the membrane and reducing thickness
• temperature decrease causes membrane rigidification and increased thickness biolink:causes

  General physical trigger underlying homeoviscous adaptation across microbes.

  • DOI:10.1007/s42770-023-01057-4 membrane rigidification and increased thickness are proposed as sensing signals that trigger adaptive responses
• homeoviscous adaptation maintains liquid-crystalline membrane state

  Broad mechanism relevant to upper-mesophile growth: cells preserve membrane function across temperature fluctuations.

  • DOI:10.1007/s42770-023-01057-4 maintain the liquid-crystalline phase at low temperature