This family consists of Carbon starvation protein CstA a predicted membrane protein. It has been suggested that CstA is involved in peptide utilisation [1].

1: Molecular and functional characterization of a carbon starvation gene of Escherichia coli. Schultz JE, Matin A; J Mol Biol 1991;218:129-140. PMID:1848300

2: CsrA regulates translation of the Escherichia coli carbon starvation gene, cstA, by blocking ribosome access to the cstA transcript. Dubey AK, Baker CS, Suzuki K, Jones AD, Pandit P, Romeo T, Babitzke P; J Bacteriol. 2003;185:4450-4460. PMID:12867454