Table 2.
Bioinformatics analysis of selected CSP random mutants: predicted signal sequence properties and translational attributes
Mutant | Amino acid sequencea | D scoreb | Cleavage siteb | Net charge of N domainc | Net hydrophobicity of H domaind | Relative translation rate prediction (AU)e | Minimum free energy (kcal mol−1)f |
---|---|---|---|---|---|---|---|
CSP | mkkkllalallallfngaqam | 0.875 | AQA-MA | +3 | 9.11 | 1.00 | –29.84 |
S2 | .yrnk.v...c...l..p... | 0.804 | AMA-HP | +2 | 8.67 | 0.53 | –31.40 |
S7 | .qe..cq...i.......e.. | 0.520 | AMA-HP* | 0 | 7.19 | 2.57 | –28.80 |
S15 | .rs...s.gv.li.a..gk.. | 0.682 | AMA-HP | +2 | 8.38 | 1.09 | –28.60 |
S38 | ..r.................. | 0.877 | AQA-MA | +3 | 9.11 | 1.00 | –29.84 |
S43 | ..s..f..em.v......... | 0.678 | AMA-HP | +2 | 7.92 | 0.99 | –24.24 |
S46 | ..rs..s....e......... | 0.671 | AMA-HP | +2 | 6.95 | 0.14 | –26.50 |
S47 | ..rtf.d.....s..s..... | 0.689 | AMA-HP | +2 | 6.95 | 0.58 | –27.20 |
S48 | ..r...v.....v....eh.. | 0.725 | AMA-HP | +3 | 9.59 | 0.33 | –27.94 |
S49 | ..r....i...rvsly..... | 0.707 | AMA-HP | +3 | 5.97 | 0.33 | –28.64 |
S54 | ..r.ff.vt.i.gfgi..... | 0.615 | AMA-HP | +3 | 9.91 | 1.64 | –25.80 |
S60 | .qq..ssr...pv.lys.... | 0.666 | AMA-HP | +1 | 4.18 | 0.87 | –26.10 |
S61 | .......v............. | 0.884 | AQA-MA | +3 | 9.13 | 1.00 | –29.74 |
Periods (.) indicate that the amino acid is identical to the one in CSP at this position.
Calculated by SignalP 4.0 (38). S7 did not meet the cutoff criteria. *, the reported cleavage site gave the best score.
Calculated for the first five residues, with amino acids D and E defined as −1, R and K defined as +1 and any other amino acid as 0.
Calculated as the sum of hydrophobicity for the hydrophobic region (residues 6 to 17), based on the normalized consensus hydrophobicity scale (47).
Calculated by the RBS calculator v1.1, reverse engineering mode (39). AU, arbitrary unit(s).
Minimum free energy predicted by RNAfold (40) for the optimal secondary structure of the region surrounding the translation initiation site. The analyzed sequence included 32 bp of the nontranslated region, the signal sequence, and 36 bp of the mature bla coding sequence.