This family includes enzymes that perform ADP-ribosylations, such as ADP-ribosylarginine hydrolase EC:3.2.2.19 which cleaves ADP-ribose-L-arginine [1]. The family also includes dinitrogenase reductase activating glycohydrolase [2], and most surprisingly jellyfish crystallins [2], although these proteins appear to have lost the presumed active site residues.
Fitzmaurice WP, Saari LL, Lowery RG, Ludden PW, Roberts GP.
Genes coding for the reversible ADP-ribosylation system of dinitrogenase reductase from Rhodospirillum rubrum.
Mol. Gen. Genet. 218 340-7 1989
[PubMed: 2506427] http://dx.doi.org/10.1007/BF00331287