TABLE 3.
Negligible hydrolysis of model peptide substrates by Aβ hydrolyzing IgVs
ND indicates not detected; one-letter amino acid code is used. Peptide-AMC substrates, 200 μM; purified IgVs and polyclonal human IgM 9010, 30 μg/ml; 37 °C. Values (means of three replicates ± S.D.) are slopes of progress curves monitored by fluorimetry as in Ref. 12.
|
Substrate
|
Hydrolysis, μM AMC/h/μM Ig
|
||
|---|---|---|---|
| IgV1,2-t 2E6 | IgVL-t′ 5D3 | IgM 9010 | |
| AE-AMC | ND | ND | ND |
| AAA-AMC | ND | ND | ND |
| IIW-AMC | ND | ND | ND |
| AAPF-AMC | ND | ND | ND |
| EKK-AMC | 0.030 ± 0.001 | 0.104 ± 0.001 | 13.1 ± 1.4 |
| VLK-AMC | ND | ND | 6.9 ± 0.4 |
| EAR-AMC | 0.005 ± 0.001 | 0.023 ± 0.001 | 61.9 ± 6.9 |
| IEGR-AMC | 0.010 ± 0.001 | 0.052 ± 0.001 | 2.0 ± 0.7 |
| PFR-AMC | ND | ND | 37.4 ± 0.7 |