TABLE 1.
Amino acid sequence variant | No. of nsSNPs | No. of other amino acid changes (no. of amino acids, location)b
|
No. of strains (%) | Genetic group of affected strains | ||
---|---|---|---|---|---|---|
Insertion | Deletion | Frameshiftc | ||||
H37Rv type | 0 | 90 (73.8) | ||||
1 | 1 | 5 (4.1) | 1 | |||
2 | 1 | 3 (2.5) | 2 | |||
3 | 4 | 4 (3.3) | 1 | |||
4 | 3 | 2 (1.6) | 1 | |||
5 | 36 | 1 (4, 294) | 1 (1, 274) | 1 (3, 221-223) | 1 (0.8) | 2 |
6 | 7 | 1 (0.8) | 2 | |||
7 | 3 | 1 (0.8) | 2 | |||
8 | 1 | 1 (4, 294) | 1 (0.8) | 3 | ||
9 | 2 | 1 (0.8) | 2 | |||
10 | 31 | 1 (4, 294) | 1 (1, 274) | 1 (3, 221-223) | 1 (0.8) | 3 |
11 | 1 (18, 17-34) | 2 (1.6) | 2 | |||
12 | 11 | 1 (0.8) | 2 | |||
13 | 6 | 1 (0.8) | 3 | |||
14 | 31 | 1 (4, 294) | 1 (0.8) | 3 | ||
15 | 1 (2, 162) | 1 (0.8) | 2 | |||
16 | 35 | 1 (1, 274) | 1 (3, 221-223) | 1 (0.8) | 1 | |
17 | 9 | 1 (0.8) | 1 | |||
18 | 1 (2, 161-162) | 1 (0.8) | 2 | |||
19d | 13 | 1 (0.8) | 2 | |||
20 | 4 | 1 (0.8) | 2 | |||
21 | 3 | 1 (0.8) | 1 |
The amino acid variants are described based on the number of nsSNPs, the in/dels, and the principal genetic group.
in/dels are described based on the number of amino acids affected and the location in the amino acid sequence, which in H37Rv is 391 amino acids long.
Two consecutive frameshifts were found in the same three strains. An insertion of a guanine at bp 659 within the gene, occurring with deletion of a guanine at bp 669, caused the frameshift to be reverted and ultimately affected three amino acids.
A codon change at position 155 from UAC to UAA resulted in an amino acid change from tyrosine to termination. The remaining 12 nsSNPs shown occur downstream.