InterPro domain: IPR022369

A family containing a number of integral membrane proteins is named after TerC protein. TerC has been implicated in resistance to tellurium, and may be involved in efflux of tellurium ions. The tellurite-resistant Escherichia coli strain KL53 was found during testing of a group of clinical isolates for antibiotic and heavy metal ion resistance [ 1 ]. The determinant of the strain's tellurite resistance was located on a large conjugative plasmid, and analyses showed the genes terB, terC, terD and terE were essential for conservation of this resistance. Members of this family contain a number of conserved aspartates which may be involved in metal ion binding.

A TerC homologue is known from the chloroplast thylakoid membrane from Arabidopsis which is important for thylakoid membrane biogenesis in the developing chloroplast [ 2 ]; it is required for insertion of proteins into the thylakoid membrane [ 3 ].

This entry represents a subset of TerC proteins which are mostly encoded on genes preceded by a structured RNA element known as the yybP-ykoY leader. The yybP-ykoY leader (also known as SraF) may function in the regulation of these genes as riboswitch [ 4 ]. This entry also includes the putative membrane-bound redox modulator Alx [ 5 ].

1. In vivo and in vitro cloning and phenotype characterization of tellurite resistance determinant conferred by plasmid pTE53 of a clinical isolate of Escherichia coli. Folia Microbiol. (Praha) 43, 589-99
2. Deletion of the chloroplast-localized AtTerC gene product in Arabidopsis thaliana leads to loss of the thylakoid membrane and to seedling lethality. Plant J. 55, 428-42
3. The Arabidopsis Tellurite resistance C protein together with ALB3 is involved in photosystem II protein synthesis. Plant J. 78, 344-56
4. New RNA motifs suggest an expanded scope for riboswitches in bacterial genetic control. Proc. Natl. Acad. Sci. U.S.A. 101, 6421-6
5. pH-dependent expression of periplasmic proteins and amino acid catabolism in Escherichia coli. J. Bacteriol. 184, 4246-58