Table 2.
Antimicrobial activity of СhBac3.4 variants against Gram-positive and Gram-negative bacteria.
| MIC a (μM) against bacteria | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Gram-negative: | Gram-positive: | GMIC b total[Gr-|Gr+] | |||||||
| Peptides | E. coli ML-35p | A. baumannii 7226/16 | K. pneumoniae ESBL 344/17 | P. aeruginosa MDR 522/17 | E. coli ESBL 521/17 | S. aureus SG-511 | MRSAATCC 33591 | S. aureus 1399/17 | |
| ChBac3.4-NH2 | 2 | 4 | 4 | 16 | 4 | 0.5 | 16-32 | 8 |
4.6
[4.6|4.6] |
| ChBac3.4-COOH | 2 | 4-8 | 4-8 | 32 | 4 | 0.5 | 32 | 8-16 |
6.0
[6.2|5.8] |
| ChBac3.4-1-NH2 | 4 | 4 | 8 | 32 | 8 | 0.25 | 16 | 8 |
5.7
[8.0|3.2] |
| ChBac3.4-1-COOH | 2-4 | 4 | 8 | 16 | 4-8 | 0.25 | 16 | 8 |
4.8
[6.2|3.2] |
| RFR-ChBac3.4-1-NH2 | 4 | 8 | 4-8 | 16 | 8 | 0.5 | 8 | 4-8 |
5.3
[7.6|2.9] |
| ChBac3.4-2-COOH | 4 | 8-16 | 8 | 16 | 4 | 0.5 | 8 | 8 |
5.5
[7.6|3.2] |
| ChBac3.4 (Н-) |
4 | 8 | 2 | 8-16 | 2 | 0.5 | 16 | 4 |
3.9*
[4.3|3.2] |
| ChBac3.4 (12-26) |
64 | 32 | 64 | 128 | 32 | 8 | 64-128 | 32 |
43.7
[55.7|29.1] |
| ChBac3.4 (1-19)-NH2 |
4 | 16 | 8 | 64 | 4 | 4 | 64 | 32 |
13.5
[10.6|20.2] |
| ChBac3.4 (1-14)-NH2 |
8 | 16 | 16 | 64 | 16 | 2 | 16 | 128 |
17.4
[18.4|16.0] |
| RFR-ChBac3.4 (1-14)-NH2 |
1 | 8 | 8 | 16 | 2 | 0.5 | 8 | 4 |
3.7*
[4.6|2.5] |
a
Minimal inhibitory concentrations (MIC) are shown as medians of 3–6 independent experiments carried out in triplicate.
b
The geometric mean of MICs measured against different bacterial strains (GMIC) is used for an overall assessment of antimicrobial activity of tested ChBac3.4 variants. GMIC values lower than that of the native ChBac3.4 are marked with asterisks. GMICs against all tested bacteria are given in bold italic; GMIC values against Gram-negative (Gr-) and Gram-positive (Gr+) strains calculated separately are given in square brackets on the left and right, respectively.