EC Number   |
Substrates |
Products |
Reversibility |
|---|
   6.2.1.45 | ATP + ubiquitin + [ubiquitin-activating protein E1]-L-cysteine |
a carboxylgroup is first activated as an adenylate followed by its direct transfer to an autonomous molecular moiety in a single enzymatic step |
AMP + diphosphate + [ubiquitin-activating protein E1]-S-ubiquitinyl-L-cysteine |
- |
? |
| 6.2.1.45 | ATP + ubiquitin + [ubiquitin-activating protein E1]-L-cysteine |
- |
AMP + diphosphate + [ubiquitin-activating protein E1]-S-ubiquitinyl-L-cysteine |
- |
? |
| 6.2.1.45 | ATP + ubiquitin + [ubiquitin-activating protein Uba1a]-L-cysteine |
- |
AMP + diphosphate + [ubiquitin-activating protein Uba1a]-S-ubiquitinyl-L-cysteine |
- |
? |
| 6.2.1.45 | ATP + ubiquitin + [ubiquitin-activating protein Uba6]-L-cysteine |
isoform Uba6 forms a covalent link with ubiquitin in vitro and in vivo, which is sensitive to reducing conditions. Recombinant E1 enzyme Uba6 can activate ubiquitin and transfer it onto the ubiquitin-conjugating enzyme UbcH5B. Ubiquitin activated by Uba6 can be used for ubiquitylation of p53 and supports the autoubiquitylation of the E3 ubiquitin ligases HectH9 and E6-AP |
AMP + diphosphate + [ubiquitin-activating protein Uba6]-S-ubiquitinyl-L-cysteine |
- |
? |
| 6.2.1.45 | ATP + ubiquitin + [ubiquitin-activating protein UBE1]-L-cysteine |
- |
AMP + diphosphate + [ubiquitin-activating protein UBE1]-S-ubiquitinyl-L-cysteine |
- |
? |
| 6.2.1.45 | ATP + ubiquitin fold modifier1 + [ubiquitin-activating enzyme Uba5]-L-cysteine |
the catalytic cysteine residue of isoform Uba5 is part of the adenylation domain in a alpha-helical motif |
AMP + diphosphate + [ubiquitin-activating enzyme Uba5]-S-(ubiquitin fold modifier1)-L-cysteine |
- |
? |
| 6.2.1.45 | ATP + Ufm1 + [ubiquitin-activating protein UBA5]-L-cysteine |
Ufm1, ubiquitin-fold modifier 1, an ubiquitin-like protein |
AMP + diphosphate + [ubiquitin-activating protein UBA5]-S-Ufm1-L-cysteine |
- |
? |
| 6.2.1.45 | more |
UBE1L2 transfers activated ubiquitin onto UbcH5b and supports E3-mediated polyubiquitylation |
? |
- |
? |
| 6.2.1.45 | more |
impaired nucleotide excision repair upon macrophage differentiation is corrected by E1 ubiquitin-activating enzyme |
? |
- |
? |
| 6.2.1.45 | more |
a lysine 48-linked polyubiquitin chain, assembled upon an internal lysine residue of a substrate protein, becomes the principle signal for recognition and target degradation by the 26S proteasome. E1 is not only essential for the initial ATP-dependent activation of ubiquitin in the ubiquitin degradtion pathway, but also capable of the catalytic extension of the polyubiquitin chain on a mono-ubiquitinated substrate |
? |
- |
? |
