High Prevalence of KatG Ser315Thr Substitution among Isoniazid-Resistant Mycobacterium tuberculosis Clinical Isolates from Northwestern Russia, 1996 to 2001

Abstract

A total of 204 isoniazid (INH)-resistant strains of Mycobacterium tuberculosis isolated from different patients in the northwestern region of Russia from 1996 to 2001 were screened by a PCR-restriction fragment length polymorphism (RFLP) assay. This assay uses HapII cleavage of an amplified fragment of the katG gene to detect the transversion 315AGC→ACC (Ser→Thr), which is associated with INH resistance. This analysis revealed a 93.6% prevalence of the katG S315T mutation in strains from patients with both newly and previously diagnosed cases of tuberculosis (TB). This mutation was not found in any of 57 INH-susceptible isolates included in the study. The specificity of the assay was 100%; all isolates that contained the S315T mutation were classified as resistant by a culture-based susceptibility testing method. The Beijing genotype, defined by IS6110-RFLP analysis and the spacer oligonucleotide typing (spoligotyping) method, was found in 60.3% of the INH-resistant strains studied. The katG S315T shift was more prevalent among Beijing genotype strains than among non-Beijing genotype strains: 97.8 versus 84.6%, respectively, for all isolates, including those from patients with new and previously diagnosed cases, isolated from 1999 to 2001 and 100.0 versus 86.5%, respectively, for isolates from patients with new cases isolated from 1996 to 2001. The design of this PCR-RFLP assay allows the rapid and unambiguous identification of the katG 315ACC mutant allele. The simplicity of the assay permits its implementation into routine practice in clinical microbiology laboratories in regions with a high incidence of TB where this mutation is predominant, including northwestern Russia

Improved rapid molecular diagnosis of multidrug-resistant tuberculosis using a new reverse hybridization assay, REBA MTB-MDR

“…In contrast, but perhaps not unexpectedly given its highly complex mechanism of action, the mutations causing INH resistance are located in more than three genes and regions (Barry et al, 1998;Slayden & Barry, 2000). Depending on the sample set analysed, it has been reported that 50-95 % of INH-resistant strains contain mutations in codon 315 of the katG gene encoding the catalase-peroxidase (Mokrousov et al, 2002;Musser et al, 1996;Piatek et al, 2000;Telenti et al, 1997) and 20-35 % harbour mutations in the inhA promoter region (Musser et al, 1996;Piatek et al, 2000;Telenti et al, 1997). Moreover, 10-15 % of INH-resistant strains have mutations in the oxyR-ahpC intergenic region, although there is no direct evidence relating mutation at this region and INH resistance (Piatek et al, 2000;Telenti et al, 1997).…”

Insights into the processes that drive the evolution of drug resistance in Mycobacterium tuberculosis

“…For instance, in the case of rifampicin resistance, hundreds of rpo B mutations have been described (not all were associated with rifampicin resistance), but more than 80% of rifampicin‐resistant isolates display mutations in three codons rpo B531, 526 and 516 (Campbell et al., 2011; Lipin et al., 2007; Pozzi et al., 1999; Telenti et al., 1993). Similar to that, among the approximately 300 mutations found in the kat G gene, the prevalence of kat G S315T mutation can vary between 32% and 95% in isoniazid‐resistant clinical isolates depending on the geographic regions and drug resistance patterns (Hazbon et al., 2006; Lipin et al., 2007; Mokrousov et al., 2002; Vilcheze & Jacobs, 2014). …”

“… Notes aNucleotide change.bSee the following studies for reference (Campbell et al., 2011; Duong et al., 2009; Hazbon et al., 2006; Hillemann et al., 2005; Lipin et al., 2007; Mokrousov et al., 2002; Müller et al., 2011; Niehaus et al., 2015; Perdigao et al., 2010; Pozzi et al., 1999; Qian et al., 2002; Shi et al., 2011; van Soolingen et al., 2000; Sreevatsan et al., 1996, 1997; Telenti et al., 1993; Von Groll et al., 2009). …”

“…For instance, the kat G S315T is prevalent in lineage 2, conversely the inh A‐15 mutation is associated mostly with lineage 1 (Casali et al., 2014; Fenner et al., 2012; Gagneux, Burgos, et al., 2006; Mokrousov et al., 2002; Nguyen, Nguyen, et al., 2017). Similar to that, the rpo B S531L mutation is observed mainly in lineage 2 compared with other lineages, while the rpo B D516V mutation is more frequent in lineage 4 (LAM family) (Casali et al., 2014; Hillemann et al., 2005; Lipin et al., 2007).…”

“…Thus, lineage 2 could be better adapted to compensate for the loss or reduced activity of this catalase‐peroxidase enzyme in the context of isoniazid resistance. This hypothesis could also explain why the Beijing strains are generally strongly associated with resistance to isoniazid, regardless of the type of kat G resistant‐associated mutations and country (Fenner et al., 2012; Gagneux, Burgos, et al., 2006; Mokrousov et al., 2002; Ribeiro et al., 2014; van Soolingen et al., 2000). …”