LdcC RNA motif

The "ldcC" RNA motif is a conserved RNA structure that was discovered by bioinformatics.
"ldcC" motif RNAs are found in Firmicutes and two species of Spirochaetes.
"ldcC" motif RNAs likely function as cis-regulatory elements, in view of their positions upstream of protein-coding genes. The genes presumably regulated by "ldcC" RNAs are decarboxylases of arginine, ornithine, S-adenosylmethionine or other substrates. Endopeptidase C39A and "potA" (a transporter of spermidine/putrescine) is also relatively common. Thus, "ldcC" RNAs could regulate polyamine metabolism.
The "ldcC" motif might have a pseudoknot in its secondary structure, but it is unclear.