Table 1.
Characteristics of isoforms of four enzymatic antioxidants in Symbiodinium
| Isoform | # of sequences | Identical sites | Clades represented | # of sequences with N-termini | Subcellular location* | TargetP reliability class [PLANT] | TargetP reliability class [NON-PLANT] | # of full length sequences | Ungapped length [aa] | Predicted molecular weight ‡ [kDa] | Predicted GPI-anchor [GPI-SOM/PredGPI] |
|---|---|---|---|---|---|---|---|---|---|---|---|
| SymMnSOD1 | 6 | 89.1% | B, C | 5 | M/S1 | M4-5; S3 | M4-5; S3-5 | 4 | 263-265 | 28.6-28.9 | No/No |
| SymMnSOD2 | 4 | 84.9% | B, D, F | 4 | M/S2 | M5; S5 | M3-5; S3 | 4 | 294-303 | 32.0-32.6 | No/No |
| SymMnSOD3 | 5 | 55.5% (73.3%3) | A, B, D | 3 | S | S2-3 | S1-2 | 2 | 246-247 | 26.5-27.2 | No/No |
| SymMnSOD (others) | 6 | A, B | 5 | S | S2-3 | S1-3 | 1 | 270 | 29.2 | No/No | |
| SymFeSOD | 4 | 92.7% | A, B, E, F | 1 | C | - | - | 1 | 201 | 21.9 | No/No |
| SymAPX1 | 23 | 26.1% | A, B, C, D, F | 14 | C | - | - | 6 | 391-397 | 42.4-43.6 | No/No |
| SymAPX2 | 7 | 67.1% | A, B, C, D | 2 | M4/S5 | M5; S1 | M4; S1 | 2 | 311/362 | 33.9/38.6 | No/No |
| SymAPX3 | 6 | 69.5% | A, D | 5 | C | - | - | 4 | 317-320 | 34.7-34.9 | No/No |
| SymAPX4 | 3 | 87.3% | B, D, F | 1 | C | - | - | 1 | 308 | 33.6 | No/No |
| SymAPX5 | 3 | 86.1% | A, D | 2 | C | - | - | 2 | 453 | 49.0/49.1 | No/No |
| SymAPX6 | 2 | 69.2% | A, B | 1 | M | M5 | S5 | 1 | 328 | 36.0 | Yes7/No |
| SymAPX (others) | 2 | A | 2 | ? | Not recognized | Not recognized | 0 | - | - | ||
| SymKatG1 | 12 | 63.6% | A, B, C, D, E, F | 5 | S | S2-5 | S1-S5 | 1 | 486 | 54.4 | Uncertain7/No |
| SymKatG2 | 4 | 73.1% | A, B, D | 3 | M6/S | M4; S5 | S2-3 | 1 | 423 | 46.7 | No/No |
Molecular characterization of superoxide dismutase (FeSOD/MnSOD), ascorbate peroxidase (APX), and catalase peroxidase (KatG) protein isoforms identified in the genus Symbiodinium. Proportion of identical residues across represented clades is indicated for each isoform (for pairwise identities between types see Additional files 1, 5 and 7). Subcellular location indicated as cytosolic (C), mitochondrial (M), or as part of the secretory pathway (S). TargetP reliability classes (1-5) are indicated, where 1 indicates the strongest prediction. Length, molecular weights, and presence of GPI anchor are based on full-length sequences.
*based on results with “PLANT” settings in TargetP 1.1. for all sequences with complete N-terminal domains.
‡weights for SOD metalloforms and KatG refer to the monomer.
1only Symbiodinium C15 M. digitata SymMnSOD1.
2only Symbiodinium B1 Mf1.05b SymMnSOD2 rep_c13368 and Symbiodinium of clade D A. hyacinthus SymMnSOD2 [GenBank:GAFP01017905].
3including Symbiodinium A1 CCMP2467 SymMnSOD3 Assembly2 sequence.
4 Symbiodinium of clade D A. hyacinthus SymAPX2 [GenBank:GAFP01018157].
5 Symbiodinium of clade D A. hyacinthus SymAPX2 [GenBank:GAFP01007188].
6 Symbiodinium of clade D A. hyacinthus SymKatG2 [GenBank:GAFP01010883].
7GPI-SOM results based on C&N-terminal signal.