CATH Domain 5c0kA00

CATH Classification

Level	CATH Code	Description
	1	Mainly Alpha
	1.10	Orthogonal Bundle
	1.10.1170	Inhibitor Of Apoptosis Protein (2mihbC-IAP-1); Chain A
	1.10.1170.10	Inhibitor Of Apoptosis Protein (2mihbC-IAP-1); Chain A

Domain Context

CATH Clusters

Superfamily	Inhibitor Of Apoptosis Protein (2mihbC-IAP-1); Chain A
Functional Family	E3 ubiquitin-protein ligase XIAP

Enzyme Information

2.3.2.27

RING-type E3 ubiquitin transferase.

based on mapping to UniProt P98170

S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)- ubiquitinyl-[acceptor protein]-L-lysine.

-!- RING E3 ubiquitin transferases serve as mediators bringing the ubiquitin-charged E2 ubiquitin-conjugating enzyme (EC 2.3.2.23) and an acceptor protein together to enable the direct transfer of ubiquitin through the formation of an isopeptide bond between the C-terminal glycine residue of ubiquitin and the epsilon-amino group of an L-lysine residue of the acceptor protein. -!- Unlike EC 2.3.2.26 the RING-E3 domain does not form a catalytic thioester intermediate with ubiquitin. -!- Many members of the RING-type E3 ubiquitin transferase family are not able to bind a substrate directly, and form a complex with a cullin scaffold protein and a substrate recognition module (the complexes are named CRL for Cullin-RING-Ligase). -!- In these complexes, the RING-type E3 ubiquitin transferase provides an additional function, mediating the transfer of a NEDD8 protein from a dedicated E2 carrier to the cullin protein (see EC 2.3.2.32). -!- Cf. EC 2.3.2.31.

UniProtKB Entries (1)

P98170

XIAP_HUMAN

Homo sapiens

E3 ubiquitin-protein ligase XIAP

PDB Structure

PDB	5C0K
External Links	PDBSum Proteopedia
Method	X-RAY DIFFRACTION
Organism
Primary Citation	Fragment-Based Drug Discovery Targeting Inhibitor of Apoptosis Proteins: Discovery of a Non-Alanine Lead Series with Dual Activity Against cIAP1 and XIAP. Chessari, G., Buck, I.M., Day, J.E., Day, P.J., Iqbal, A., Johnson, C.N., Lewis, E.J., Martins, V., Miller, D., Reader, M., Rees, D.C., Rich, S.J., Tamanini, E., Vitorino, M., Ward, G.A., Williams, P.A., Williams, G., Wilsher, N.E., Woolford, A.J. J.Med.Chem.