May act as a carrier protein for the ROS scavenging lipoyl moiety and/or as a substrate for oxidoreductases such as SAV0322 and SAV0323. Lipoylated GcvH-L directly interacts with SAV0325, which reverses the SirTM-mediated mono-ADP-ribosylation of GcvH-L, and with the oxidoreductase SAV0322. Is lipoylated on K-56 by LplA2 (SAV0327) and then mono-ADP-ribosylated, probably on D-27, by SirTM (SAV0326). The mono-ADP-ribosylation state of GcvH-L might regulate the availability of the lipoyl moiety for redox reactions; ADP-ribosylation would inhibit the interaction of the oxidoreductase with GcvH-L when it is not required, thus ADP-ribosylation of GcvH-L might be acting to keep the response 'off' under non-stress conditions.