Ribosomal protein L4 of Lactobacillus rhamnosus LRB alters resistance to macrolides and other antibiotics

In this study, we isolated a nontargeted mutant that was particularly sensitive to acid stress. Using next generation sequencing, we further mapped the putative mutations in the genome and found that the mutant had acquired a deletion of 75 base pairs in therplD gene that encodes the large ribosomal subunit L4. The mutant had a growth defect at 37 °C and at ambient temperature. Further antibiotic sensitivity analyses indicated that the mutant is relatively more resistant to erythromycin and chloramphenicol; two antibiotics that target the 50S subunit. In contrast, the mutant was more sensitive to tetracycline, which targets the 30S subunit. Thus, it appears that nontargeted mutations could significantly alter the antibiotic resistance profile ofL. rhamnosus. Our study raises concern that probiotic use ofL. rhamnosus should be carefully monitored to avoid unintended consequences.
Source: Molecular Oral Microbiology - Category: Microbiology Authors: Tags: ORIGINAL ARTICLE Source Type: research