Table 2.
T. brucei aaRS enzyme classification, subcellular localization, and essentialitya
| aaRS no. | aaRS | GeneDB accession no. | Subclass | IFA (reference) | Mass spectrometry countb |
Localization | Growth defect (reference)d | |
|---|---|---|---|---|---|---|---|---|
| WC | MP | |||||||
| 1 | AlaRS | Tb927.6.700 | IIc | − | 23 | 3 | C/M | Yes |
| 2 | ArgRS | Tb927.11.1990 | Ic | − | 23 | 2 | C/M | − |
| 3 | AsnRS | Tb927.4.2310 | IIb | − | 10 | 3 | C/M | − |
| 4 | AspRS-2 | Tb927.10.1260 | IIb | M (26) | 0 | 8 | M | Yes (26) |
| 5 | AspRS-1 | Tb927.6.1880 | IIb | C (26 | 12 | 0 | C | Yes (26) |
| 6 | CysRS | Tb927.6.950 | Ia | C | 9 | 27 | C/M | − |
| 7 | GlnRS | Tb927.9.5210 | Ic | C/M (30)c | 14 | 0 | C/M | Yes (30) |
| 8 | GluRS | Tb927.6.4590 | Ic | C/M (30)c | 10 | 8 | C/M | Yes (30) |
| 9 | GlyRS | Tb927.11.9640 | IIc | C | 25 | 13 | C/M | − |
| 10 | HisRS | Tb927.6.2060 | IIa | − | 8 | 0 | C | − |
| 11 | IleRS | Tb927.10.9190 | Ia | C/M (29) | 31 | 70 | C/M | Yes (24, 29) |
| 12 | LeuRS | Tb927.11.3730 | Ia | − | 28 | 13 | C/M | Yes |
| 13 | LysRS-1 | Tb927.8.1600 | IIb | C (27) | 13 | 4 | C/M | Yes (27) |
| 14 | LysRS-2 | Tb927.6.1510 | IIb | M (27) | 0 | 11 | M | Yes (27) |
| 15 | MetRS | Tb927.10.1500 | Ia | C | 22 | 19 | C/M | Yes (31) |
| 16 | PheRS-α | Tb927.11.14120 | IIc | − | 8 | 4 | C/M | − |
| 17 | PheRS-β | Tb927.11.2360 | IIc | − | 10 | 13 | C/M | − |
| 18 | ProRS | Tb927.10.12890 | IIa | C/M | 28 | 11 | C/M | Yes |
| 19 | SerRS | Tb927.11.7170 | IIa | C | 11 | 3 | C/M | Yes (28) |
| 20 | ThrRS | Tb927.5.1090 | IIa | C | 23 | 16 | C/M | Yes (Kalidas et al.) |
| 21 | TrpRS-1 | Tb927.3.5580 | Ib | C (25) | 0 | 0 | C | Yes (25) |
| 22 | TrpRS-2 | Tb927.8.2240 | Ib | M (25) | 0 | 39 | M | Yes (25, 70) |
| 23 | TyrRS | Tb927.7.3620 | Ib | − | 6 | 2 | C/M | − |
| 24 | ValRS | Tb927.6.4480 | Ia | C | 27 | 20 | C/M | − |
The enzyme classification is based on sequence and motif similarity (1, 2). The immunofluorescence assay (IFA) and growth defect results are reported here (Fig. 1 and 2) and elsewhere, as indicated by the citations in parentheses or as reported by S. Kalidas, I. Cestari, K. Stuart, and M. Phillips (unpublished data). Abbreviations: C, cytoplasmic localization; M, mitochondrial localization; C/M, dual localization; C/M, lower-confidence dual localization; −, not determined.
Total spectral counts for each aaRS identified by mass spectrometry of whole-cell (WC) or purified mitochondrial (MP) lysates. The mass spectrometry analyses were performed on procyclic forms.
GlnRS and GluRS were localized by Western analysis of cytosolic and mitochondrial subcellular fractions (30).