α-Actinin TvACTN3 of Trichomonas vaginalis Is an RNA-Binding Protein That Could Participate in Its Posttranscriptional Iron Regulatory Mechanism
Table 2
Peptides identified by MALDI-TOF-MS analysis of the 135-kDa protein band of T. vaginalis that interacted with RNA IRE-tvcp4 probe by UV cross-linking assay (Figure 2(a))a.
Peptide numberb
Measured / (av)c
Calculated / (av)d
Errore
Positionf
Peptide sequences (aa)g
1
1516.59
1516.65
−0.06
6–18
(R)GLLDDAWEQTQIK(V)
2
1749.93
1749.91
0.02
32–47
(K)GIPFDNVLEEFADGVK(L)
3
1640.95
1641.02
−0.07
48–61
(K)LIQLLEIVSKEPMK(G)
4
1624.73
1624.81
−0.08
119–132
(K)FMIEEISVEEATAR(D)
5
928.98
929.11
−0.13
133–140
(R)DALLLWAK(K)
6
2099.52
2099.28
0.24
171–187
(K)FRPNMLDYDSLDQTQQK(E)
7
2114.98
2115.28
−0.30
171–187
(K)FRPNMLDYDSLDQTQQK(E) + Oxidation (M)
8
2030.39
2030.24
0.15
220–237
(K)SVVTQVAEFFHFFAGESK(T)
9
1308.21
1308.39
−0.18
254–264
(K)AIEEEALNYEK(Q)
10
1369.87
1369.63
0.24
294–304
(K)SKLFNCIKFGR(V)
11
1180.53
1180.44
0.09
305–314
(R)VVRPVIVDKR(G)
12
1279.12
1279.48
−0.36
340–350
(K)EELLPPNLNLK(F)
13
1392.58
1392.51
0.07
398–409
(K)AINLTGDLYEQR(D)
14
1934.50
1934.07
0.43
410–427
(R)DALNNYLQQAQEAAGTVK(E)
15
1599.90
1599.83
0.08
428–440
(K)ELQPQFVELVELR(L)
16
1847.28
1847.11
0.17
448–464
(R)TVIAVDGEFEQLIATIK(R)
17
2003.26
2003.30
−0.04
448–465
(R)TVIAVDGEFEQLIATIKR(L)
18
1321.37
1321.44
−0.06
482–492
(K)KIEEYNQAAQK(Y)
19
1214.35
1214.33
0.03
502–512
(K)QDLEAIAGELR(E)
20
1762.73
1762.98
−0.25
530–544
(R)NGVSDIRPMFQELEK(Q)
21
1779.30
1778.98
0.32
530–544
(R)NGVSDIRPMFQELEK(Q) + Oxidation (M)
22
3063.49
3063.38
0.12
545–572
(K)QSLHLGIENTPDAVTAMYTACLSQAQDK(I)
23
2108.58
2108.35
0.24
628–645
(K)ASIQPTLEEPYQYLQSIK(Y)
24
3199.79
3199.39
0.40
660–687
(R)DSDITFAFLTTLLNQLEEQLQSESNDAR(I)
25
1363.80
1363.47
0.33
698–708
(K)YVDIANEFHQK(V)
26
1732.90
1732.94
−0.04
720–734
(R)RNAYLSAQLELGNKR(E)
27
1576.51
1576.75
−0.24
721–734
(R)NAYLSAQLELGNKR(E)
28
3097.45
3097.48
−0.03
750–777
(R)DTLHIRVNDSPATISKVYANALQIITDK(L)
29
1656.07
1655.93
0.14
802–816
(K)VVQNVELTGTLLELK(D)
30
3332.99
3332.65
0.34
824–851
(K)AQAQEILPELPTLDAPWEDLCDFNLNYR(V)
31
1549.64
1549.68
−0.04
992–1004
(K)GLQISEEQLTEFR(E)
32
2601.90
2601.78
0.12
1005–1024
(R)ETFNHFDKDHTNFLQYFELR(A)
33
1027.15
1027.13
0.03
1054–1061
(K)LNFDEYVK(F)
34
1024.19
1024.19
0.00
1062–1069
(K)FMLDHFSK(A)
35
3225.53
3225.52
0.01
1082–1109
(K)AIANNNPILTDAQLDQYFKGEEAEYLRK(V)
Masses listed represent 43% sequence coverage with MS-Fit MOWSE score and 212 Mascot score and expect value. bConsecutive number assigned to the identified peptides. cMeasured peptide mass average [/ (av)] obtained by MALDI-TOF-MS after tryptic digestion of the 135-kDa protein band excised from a duplicate CBB-stained gel used as a control for the UV cross-linking assays (Figure 2(a)). This protein was identified as actinin3 from T. vaginalis (tvactn3, TVAG239310). dCalculated peptide mass average [/ (av)] obtained from a theoretical tryptic digestion of the deduced amino acid sequence of the T. vaginalis tvactn3 gene (TVAG 239310; tvactn3) reported in the genome of T. vaginalis [29]. eError represents the difference after comparing the measured and calculated peptide mass averages [/ (av)]. ePosition in amino acid residues of the identified peptides (start-end) in the deduced amino acid sequence of T. vaginalis tvactn3 gene, tvactn3. gAmino acid sequence of the peptides obtained from a theoretical tryptic digestion of tvactn3 (see Figure S1).