9.B.398. The Uncharacterized Prokaryotic Membrane Protein-4 (UPMP4) Family The proteins of this family are small, ~140 - 150 aas and have 4 TMSs in a 1 + 1 + 2 TMS arrangement.
Examples:
TC#	Name	Organismal Type	Example
9.B.398.1.1	Phosphate-starvation-inducible PsiE family protein of 141 aas and 4 TMSs in a 2 + 2 TMS arrangement.		PsiE of Daejeonella rubra

9.B.398.1.2	PsiE of 159 aas and 4 TMSs		PsiE of Marinomonas aquimarina

9.B.398.1.3	Phosphate-starvation-inducible PsiE family protein of 140 aas and 4 TM		PsiE of Methanomethylovorans hollandica

9.B.398.1.4	Phosphate-starvation-inducible PsiE family protein of 175 aas and 4 TMSs in a 1 + 3 TMS arrangement.		PsiE of Methylocella tundrae

9.B.398.1.5	Diguanylate cyclase of 173 aas and 4 TMSs in a 1 + 1 + 2 TMS arrangement.		Diguanylate cyclase of Acidihalobacter aeolianus

9.B.398.1.6	Phosphate-starvation-inducible PsiE family protein of 324 aas with an N-terminal hydrophilic 180 aas followed by a shorter 4 TMS integral membrane protein domain where the TMSs are in a 1 + 3 TMS arrangement.		PsiE of Thiorhodococcus minor