Table 2. Biochemical Characteristics of Mitochondrial Autoantigens in PBC.
| Autoantige n |
Molecular Weight |
Biochemical Function | Cofactors | Epitope | Predomina nt IgG isotype |
|---|---|---|---|---|---|
| PDC-E2 | 70 kDa | Transfers acetyl group from pyruvate to CoA to form acetyl-CoA |
Lipoic acid CoA |
Lipoyl domains | IgG3 |
| BCOADC- E2 |
52 kDa | Transfer acyl group from alpha keto acids to CoA to form acyl-CoA |
Lipoic acid CoA |
Lipoyl domain | IgG2 |
| OGDC-E2 | 48 kDa | Decarboxylation of alpha ketoglutarate and the addition of CoA to form succinyl-CoA |
Lipoic acid CoA |
Lipoyl domain | IgG2 |
| E3BP | 55KDa | Anchoring dihydrolipoamide dehydrogenase (E3) to PDC-E2 |
Lipoic Acid | Lipoyl domain | ND* |
| PDC-E1 alpha |
41KDa | Decarboxylation of pyruvate to form 2(-1-hydroxyethylidene)-TPP and reductive acetylation to form acetyl- lipoate |
Thiamine Pyrophosphate |
Phosphorylation site and the thiamine pyrophosphate binding site. |
ND |
*
ND: Non-determined