This is the N-terminal domain of Ubiquitin-like modifier-activating enzyme ATG7. In Arabidopsis this domain binds the E2 enzymes ATG10 and ATG3 [1].

1: Noncanonical recognition and UBL loading of distinct E2s by autophagy-essential Atg7. Yamaguchi M, Matoba K, Sawada R, Fujioka Y, Nakatogawa H, Yamamoto H, Kobashigawa Y, Hoshida H, Akada R, Ohsumi Y, Noda NN, Inagaki F; Nat Struct Mol Biol. 2012;19:1250-1256. PMID:23142983