8.A.59 The SLC and TCST-Associated Component (STAC-A) Family 

Transmembrane receptors, integral components of sensory pathways in prokaryotes, share a common dimeric architecture, consisting in its basic form of an N-terminal extracellular sensor, two transmembrane helices, and an intracellular effector. An archaeal receptor, Af1503 (here designated STAC-A) from Archaeoglobus fulgidus has the two usual TMSs, but is C-terminally shortened, lacking a recognizable effector module. Instead, a HAMP domain forms the sole extension for signal transduction in the cytosol (Korycinski et al. 2015).  Members of this family are found both as stand-alone proteins and as domains within extant receptors. In general, the latter appear as connectors between members of the Solute:Sodium Symporter Family (TC#2.A.21; SLC5) transmembrane domains and two-component signal transduction domains. This is seen, for example, in the histidine kinase CbrA, which is a global regulator of metabolism, virulence, and antibiotic resistance in Pseudomonads. This domain family mediates signal transduction in systems regulating transport processes (Korycinski et al. 2015).



This family belongs to the Adenylate/Guanylate Cyclase (A/GCyc) Superfamily.

Examples:

TC#NameOrganismal TypeExample
8.A.59.1.1

Regulator of SSS family transporters, STAC-A of 338 aas and 2 TMSs (N- and C-terminal) (Korycinski et al. 2015).

STAC-A of Archaeoglobus fulgidus

 
8.A.59.1.2

Putative sensor with HAMP domain of 324 aas and 2 TMSs

Sensor protein of Methanolacinia petrolearia (Methanoplanus petrolearius)

 
8.A.59.1.3

Methyl-accepting chemotaxis protein McpB of 491 aas and 2 probable TMSs, N- and C-terminal.

McpB of Candidatus Thorarchaeota archaeon AB_25

 
Examples:

TC#NameOrganismal TypeExample
Examples:

TC#NameOrganismal TypeExample
Examples:

TC#NameOrganismal TypeExample