Characterization of the rpsL and rrs genes of streptomycin‐resistant clinical isolates of Mycobacterium tuberculosis in Japan

Abstract

Mutations in the rpsL and rrs genes associated with streptomycin resistance in Mycobacterium tuberculosis clinically isolated in Japan were characterized. The rpsL genes of 172 clinical isolates were amplified by PCR and classified into two groups on the basis of MboII restriction digestion. Thirty-three out of 54 (61·1%) streptomycin-highly resistant isolates (MIC × 200 mg ml −1 ) were not digested by MboII. By contrast, the remaining 21 of 54 (38·9%) streptomycin-highly resistant isolates, all of 41 isolates with streptomycin resistance at a lower level (20 mg ml −1 ³ MIC ¾ 200 mg ml −1 ), and all of 77 streptomycinsensitive isolates, were restricted. Thus, all isolates resistant for MboII digestion showed a high level of resistance to streptomycin. Subsequently, the sequence for the rpsL and rrs genes from the 46 isolates were analysed. Eighteen out of 19 (94·7%) streptomycin-highly resistant isolates carried a mutation in any rpsL gene at position 43 or 88, or the rrs gene ; 10 out of 17 (58·8%) streptomycin-resistant isolates at a lower level were confirmed to exhibit the mutation of either the mutated rpsL gene at position 88, or the rrs gene. In the total 36 streptomycin-resistant isolates, the mutation of the rpsL or rrs gene was observed in 28 streptomycin-resistant isolates, corresponding to 77·8%, whereas none of the streptomycin-sensitive isolates had mutations in either the rpsL or rrs gene.

Rapid, simple, and culture-independent detection of rpsL codon 43 mutations that are highly predictive of streptomycin resistance in Mycobacterium tuberculosis.

“…The prevalence of rpsL codon 43 substitutions in SM resistant M. tuberculosis can be estimated from eight previous reports, in each of which 25 or more SM resistant isolates (cultures) were examined. 4,[6][7][8][9][10][11][12] In total, the mutation was found in 146 (42%) of 345 SM resistant cultures. It was not found in any of the 228 SM sensitive isolates investigated.…”

“…7), France (no. [8][9][10][11][12], and Spain (no. [13][14][15][16], known or suspected to be infected with SM resistant M. tuberculosis (Table 1).…”

Rapid Detection of Pyrazinamide-Resistant Mycobacterium tuberculosis by a PCR-Based In Vitro System

“…A lot of mutations related to the resistance to anti-TB drugs were investigated for rifampin (18,20,21), isoniazide (1,25,26), ethambutol (2,17), streptomycin (8,11), kanamycin (19), and fluoroquinolones (5). The same kind of work on PZA is especially important because the susceptibility test for M. tuberculosis with media is sometimes unsettled due to the low level of pH dependence of this method (3).…”

“…Ethambutol-resistant M. tuberculosis strains carried mutations on a certain part of the gene coding for alabinosyl transferase (2,17). Mutations on the rrs and rpsL genes coding for the 16S ribosomal RNA and ribosome protein S12, respectively, confer streptomycin resistance (8,11). A part of the kanamycin-resistant phenotype can be detected by identifying the mutations on the rrs gene (19).…”

Detection of a mutation at codon 43 of the rpsL gene in Xanthomonas oryzae pv. oryzicola and X. oryzae pv. oryzae by PCR-RFLP

“…oryzicola and X. oryzae pv. oryzae could be rapidly identified by a simple, low-cost PCR-RFLP method (Katsukawa et al, 1997). This method, however, could not detect mutations at codon 88 of rpsL, and developing a PCR-RFLP method or other method to rapidly and easily detect mutations at this codon requires additional research.…”