TABLE 3.
Summary of 4 amino acid mutations in the katG gene products of 26 (14 MDR, 7 XDR, and 5 fully susceptible) M. tuberculosis isolates from South Africa deduced by Ion Torrent sequencing, Hain LPA genotyping, and culture
| No. of isolates | Amino acid substitution(s)a yielded by the katG gene (2,447 bp) | Isoniazid result by: |
||
|---|---|---|---|---|
| Ion Torrentb | Hain LPA | Bactec MGIT 960 | ||
| 11 | S315T | Resistant | Resistant | Resistant |
| 5 | S315T, R463L | Resistant | Resistant | Resistant |
| 1 | W191R, R463L | Sensitive | Sensitive | Sensitive |
| 7 | Wild typea | Sensitive | Sensitive | Sensitive |
| 1 | R463L | Sensitive | Sensitive | Sensitive |
| 1 | N138H | Sensitive | Sensitive | Sensitive |
a
Compared to the H37Rv reference strain.
b
Isoniazid resistance is known to occur in the katG product at position 315 (S→T) (indicated in bold).