Table 1.
Mass spectrometry analysis of peptide fragments of the major 50–55 kDa band of Trypanosoma cruzi extract corresponding to T. cruzi β-tubulin.
| Starta | End | Miss | Peptide sequence | Mr (expt)b | Mr (calc) | Delta | m/zc |
|---|---|---|---|---|---|---|---|
| 310 | 318 | 0 | R.YLTASALFR.G | 1,040.5700 | 1,040.5655 | 0.0046 | 1,041.5773 |
| 253 | 262 | 0 | K.LAVNLVPFPR.L | 1,124.6709 | 1,124.6706 | 0.0003 | 1,125.6782 |
| 242 | 251 | 0 | R.FPGQLNSDLR.K | 1,145.5862 | 1,145.5829 | 0.0033 | 1,146.5935 |
| 381 | 390 | 0 | R.VGEQFTAMFR.R | 1,184.6026 | 1,184.5648 | 0.0378 | 1,185.6099 |
| 381 | 390 | 0 | R.VGEQFTAMFR.R + Oxid. (M) | 1,200.5578 | 1,200.5598 | −0.0019 | 1,201.5651 |
| 242 | 252 | 1 | R.FPGQLNSDLRK.L | 1,273.6710 | 1,273.6779 | −0.0068 | 1,274.6783 |
| 47 | 58 | 0 | R.INVYFDEATGGR.Y | 1,340.6339 | 1,340.6361 | −0.0022 | 1,341.6412 |
| 381 | 391 | 1 | R.VGEQFTAMFRR.K + Oxid. (M) | 1,356.6472 | 1,356.6609 | −0.0136 | 1,357.6545 |
| 63 | 77 | 0 | R.AVLIDLEPGTMDSVR.A | 1,614.8089 | 1,614.8287 | −0.0198 | 1,615.8162 |
| 63 | 77 | 0 | R.AVLIDLEPGTMDSVR.A + Oxid. (M) | 1,630.7975 | 1,630.8236 | −0.0261 | 1,631.8048 |
| 263 | 276 | 0 | R.LHFFMMGFAPLTSR.G | 1,653.7986 | 1,653.8160 | −0.0174 | 1,654.8059 |
| 263 | 276 | 0 | R.LHFFMMGFAPLTSR.G + Oxid. (M) | 1,669.7885 | 1,669.8109 | −0.0224 | 1,670.7958 |
| 263 | 276 | 0 | R.LHFFMMGFAPLTSR.G + 2 Oxid. (M) | 1,685.7819 | 1,685.8058 | −0.0239 | 1,686.7892 |
| 263 | 276 | 0 | R.LHFFMMGFAPLTSR.G + 2 Oxid. (M) | 1,685.7819 | 1,685.8058 | −0.0239 | 1,686.7892 |
| 337 | 350 | 0 | K.NSSYFIEWIPNNIK.S | 1,723.8311 | 1,723.8569 | −0.0258 | 1,724.8384 |
| 47 | 62 | 1 | R.INVYFDEATGGRYVPR.A | 1,855.9092 | 1,855.9217 | −0.0125 | 1,856.9165 |
| 363 | 379 | 0 | K.MAVTFVGNNTCIQEMFR.R + Carbam. (C); Oxid. (M) | 2,032.9008 | 2,032.9169 | −0.0161 | 2,033.9081 |
| 104 | 122 | 1 | K.GHYTEGAELIDSVLDVCRK.E + Carbam. (C) | 2,161.0022 | 2,161.0474 | −0.0451 | 2,162.0095 |
| 78 | 103 | 0 | R.AGPYGQIFRPDNFIFGQSGAGNNWAK.G | 2,811.2385 | 2,811.3517 | −0.1132 | 2,812.2458 |
| gi|18568139 beta-tubulin 1.9 (T. cruzi) | |||||||
| Score: 105 sequence coverage: 36%d | |||||||
aPeptide sequences and their corresponding “start” and “end” positions, as well as the number of missing cleavages are indicated.
bExpected and calculated molecular weight (in Da) for each peptide are shown; deltas are differences between expected and calculated values.
cMass/charge ratio observed in MS spectrum (m/z).
dThe Mascot score for protein identification and the % of protein sequence coverage given by the identified peptides are also indicated.
Oxid. (M), methionine oxidation; Carbam. (C), cys-carbamidomethylation.