CATH Domain 4mdkD00

CATH Classification

Level	CATH Code	Description
	3	Alpha Beta
	3.10	Roll
	3.10.110	Ubiquitin Conjugating Enzyme
	3.10.110.10	Ubiquitin Conjugating Enzyme

Domain Context

CATH Clusters

Superfamily	Ubiquitin Conjugating Enzyme
Functional Family	Ubiquitin-conjugating enzyme E2 R2

Enzyme Information

2.3.2.23

E2 ubiquitin-conjugating enzyme.

based on mapping to UniProt P49427

S-ubiquitinyl-[E1 ubiquitin-activating enzyme]-L-cysteine + [E2 ubiquitin-conjugating enzyme]-L-cysteine = [E1 ubiquitin-activating enzyme]-L-cysteine + S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L- cysteine.

-!- The E2 ubiquitin-conjugating enzyme acquires the activated ubquitin from the E1 ubiquitin-activating enzyme (EC 6.2.1.45) and binds it via a transthioesterification reaction to itself. -!- In the human enzyme the catalytic center is located at Cys-87 where ubiquitin is bound via its C-terminal glycine in a thioester linkage. -!- Formerly EC 6.3.2.19.

2.3.2.24

(E3-independent) E2 ubiquitin-conjugating enzyme.

based on mapping to UniProt P49427

S-ubiquitinyl-[E1 ubiquitin-activating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E1 ubiquitin-activating enzyme]-L-cysteine + N(6)- monoubiquitinyl-[acceptor protein]-L-lysine.

-!- The enzyme transfers a single ubiquitin directly from an ubiquitinated E1 ubiquitin-activating enzyme to itself, and on to a lysine residue of the acceptor protein without involvement of E3 ubiquitin transferases (cf. EC 2.3.2.26, EC 2.3.2.27). -!- It forms a labile ubiquitin adduct in the presence of E1, ubiquitin, and Mg(2+)-ATP and catalyzes the conjugation of ubiquitin to protein substrates, independently of E3. -!- This transfer has only been observed with small proteins. -!- In vitro a transfer to small acceptors (e.g. L-lysine, N-acetyl-L- lysine methyl ester) has been observed.

UniProtKB Entries (1)

P49427

UB2R1_HUMAN

Homo sapiens

Ubiquitin-conjugating enzyme E2 R1

PDB Structure

PDB	4MDK
External Links	PDBSum Proteopedia
Method	X-RAY DIFFRACTION
Organism
Primary Citation	E2 enzyme inhibition by stabilization of a low-affinity interface with ubiquitin. Huang, H., Ceccarelli, D.F., Orlicky, S., St-Cyr, D.J., Ziemba, A., Garg, P., Plamondon, S., Auer, M., Sidhu, S., Marinier, A., Kleiger, G., Tyers, M., Sicheri, F. Nat.Chem.Biol.