Table 1.
Type 2 RIPs from Sambucus.
| Tissue | Protein | Mr (SDS-PAGE) (kDa) | Sugar Spec. | Yield a | IC50 (nM) | |||
|---|---|---|---|---|---|---|---|---|
| Whole | A Chain | B Chain | ||||||
| A | leaves | ebulin l | 56.0 | 26.0 | 30.0 | Gal | 3.2 | 0.15 |
| fruits | ebulin f | 56.0 | 26.0 | 30.0 | Gal | 1.6 | 0.03 | |
| blossoms | ebulin blo | 60.0 b | 34.0 | 30.0 | Gal | 5.9 | - | |
| rhizome | ebulin r1 | 56.0 | 26.0 | 30.0 | Gal | 1.34 | 0.34 | |
| rhizome | ebulin r2 | 56.0 | 26.0 | 30.0 | Gal | 0.56 | 1.14 | |
| rhizome | SEA I | 140.0 | 30.0 | 35.0 | Neu5Ac-Gal/GalNAc | 6 | 1 | |
| B | bark | nigrin b | 58.0 | 26.0 | 32.0 | Gal/GalNAc | 254 | 0.1 |
| bark | basic nigrin b | 64.0 | 32.0 | 32.0 | no determined | 90 | 0.02 | |
| bark | SNA-I | 240.0 | 33.0 | 35.0 | Neu5Ac-Gal/GalNAc | 100 | 1.65 | |
| bark | SNA-I’ | 120.0 | 32.0 | 35.0 | Neu5Ac-Gal/GalNAc | 0.2 | 1.25 | |
| bark | SNRLP1 | 68.0 | 34.0 | 34.0 | GalNAc oligomers | 100 c | 7 | |
| bark | SNRLP2 | 62.0 | 30.0 | 32.0 | GalNAc oligomers | - | 7 | |
| bark | SNA-V | 120.0 | - | - | Gal/GalNAc | - | - | |
| fruits | nigrin f | 58.0 | 26.0 | 31.6 | Gal | 1.3 | 0.03 | |
| seeds | nigrin s | 57.3 | 26.0 | 31.0 | Gal | - | - | |
| C | bark | sieboldin b | 60.0 | 27.0 | 33.0 | Neu5Ac-Gal/GalNAc | 2.6 | 0.9 |
| bark | SSA | 115.4 | 28.7 | 29.0 | Neu5Ac-Gal/GalNAc | - | >100 | |
Notes: A: S. ebulus L.; B: S. nigra L.; C: S. sieboldiana L. Type 2 RIPs have been also detected in the bark of S. mexicana L., S. racemosa L., S. peruviana L. and leaves of S. nigra L. (unpublished results). a yield per 100 g of starting material; b the molecular mass determined by mass spectrometry is 63,225; c mixture of SNRLP1 and SNLRP2. IC50: concentration required to inhibit translation in a 50%; unless indicated translation was assayed with reduced RIPs in rabbit reticulocyte lysates. Gal: d-galactose; Man: manose; GalNAc: N-acetylgalactosamine; Neu5Ac: N-acetyl-neuraminic acid (sialic acid) [13,26].