Table 2.
Identification of 12 Arabidopsis Proteins from the 2-D Electrophoresis Gels Shown in Figure 1
| Spot No. | Molecular Mass (kD) |
pI | Identitya | Accession No.b |
MALDI Percent Coverage at 50 ppmc |
Localization and Cleavage Site Predictione
|
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| SignalP
|
|||||||||||||
|
MS/MS Sequenced |
TargetingPathway | TargetP | Predotar | Euk | Gram− | Gram+ | N Terminus | ||||||
| 74 | 18.4 | 4.7 | 2-Cys peroxiredoxin | 7242491 (At3g11630) |
APDFEAEAVFDQEFIK (1) | TAT | C2/48 | P 1 | 69-AQA-DD | 69-AQA-DD | |||
| 68 | 17.1 | 5.3 | Peroxiredoxin-like | 7529720 (At3g52960) |
YAILADDGVVK (3) | TAT | C1/56 | P 0.9 | 71-VTI-SI | 73-ASI-SV | 73-SVXXKf | ||
| 79 | 22.2 | 4.7 | Putative isomerase | 7287985 (At3g60370) |
38 | TAT | C5/42 | Neither | 53-SSS-AK | 54-SSA-KT | 54-SSA-KT | ||
| 89 | 34.6 | 4.3 | Chaperone GrpE | 4583546 (At5g11710) |
45 | TAT | C2/64 | Neither | 67-ASG-EA | 68-SGE-AE | 67-ASG-EA | ||
| 69 | 17.6 | 5.6 | Putative protein | 5840783 (At5g58250) |
VHFLVANAK (7) | Sec + other | C1/52 | M 0.8 | 18-AAA-CR | 58-KTA-AT | 58-KTA-AT | ||
| 60 | 12.1 | 4.6 | Thioredoxin m1 | 2809238 (At1g03680) |
35 | Sec + other | C2/48 | Neither | 69-CEA-QD | ||||
| 61 | 13.3 | 5.0 | Thioredoxin m2 | 4206206 (At4g03520) |
34 | Sec + other | C1/56 | Neither | 75-CEA-QE | 73-EAQETf | |||
| 62 | 14.3 | 5.3 | Thioredoxin m4 | 6539614 (At3g15360) |
21 | Sec + other | C1/82 | P 0.9 | 27-SSA-AP | 27-SSA-AP | 69-RIA-RG | 76-EAQDTf | |
| 77 | 21.3 | 6.3 | Carbonic anhydrase | 14343 (At3g01500) |
46 | Sec + other | C2/32 | P 0.8 | 19-SQS-SL | 64-VFA-AP | 64-VFA-AP | 66-APXIAf | |
| 131 | 75.9 | 4.9 | Hsp70 | 7441883 (At4g24280) |
21 | Sec + other | C1/92 | P 0.8 | 93-AVA-AM | ||||
| 130 | 61.8 | 5.0 | Cpn60 | 2506276 (At2g28000) |
24 | Sec + other | C2/45 | P 1 | 14-VLC-SS | 49-ANV-KE | |||
| 113 | 20.6 | 6.2 | Cpn21 | 4127456 (At5g20720) |
23 | Sec + other | C2/50 | P 1 | 19-SLA-SL | 92-AQS-KP | |||
The locations of these proteins are either in the thylakoid lumen or peripherally attached to the stroma side of the thylakoid membrane. All proteins were identified by MALDI-TOF MS and/or nano-ESI/MS/MS. N termini for four proteins were determined by Edman sequencing.
Identity given in NCBI completed by domain prediction found by Pfam, Blocks, Prints, Prodom, or Phi-Blast.
Accession numbers in NCBI and in MIPS (in parentheses).
Percentage of coverage at 50 ppm for the MALDI-TOF peptides.
Sequence tag identified by ESI/MS/MS; additional sequences were identified (numbers in parentheses) but are not shown.
Localization, reliability class, and cleavage site prediction by TargetP (C for chloroplast), localization and score by Predotar (P for plastid, M for mitochondria), cleavage site prediction of the lumenal transit peptide by three versions of SignalP developed for eukaryotes (Euk), Gram-negative or Gram-positive bacteria, and in boldface when this prediction fits with the N-terminal Edman sequence.
N-terminal Edman sequence tag identified in this study.