Products & Services


Nanopore sequencing offers advantages in all areas of research. Our offering includes DNA sequencing, as well as RNA and gene expression analysis and future technology for analysing proteins.

Learn about applications
View all Applications
News Explore

A fluoroquinolone-sensitive Shigella sonnei UKMCC1015 downregulates the expression of ribosomal proteins in response to sub-lethal concentration of norfloxacin


Date: 9th December 2020 | Source: BioRxiv

Authors: Wong Bao Chi, Muhammad Zarul Hanifah Md Zoqratt, Gan I-Ning, Qasim Ayub, Tan Hock Siew.

Shigella spp. commonly causes gastroenteritis known as shigellosis, and severe cases require antibiotic treatments. However, the increased presence of antibiotics in the environment in recent years can lead to antibiotic resistance. Sub-lethal antibiotic concentrations can promote resistance, but its effect on sensitive bacteria prior to resistance development is unknown.

In this study, the complete genome of Shigella sonnei UKMCC1015, a sensitive strain from Malaysia is presented. Subsequently, the transcriptomic response of this strain towards sub-MIC levels of norfloxacin, a commonly used fluoroquinolone is investigated. This study reveals that the expressions of the antimicrobial resistance genes and antibiotic targets (DNA gyrase and topoisomerase IV) are not affected. Interestingly, multiple ribosomal protein operons were downregulated while a small regulatory RNA (sRNA), GcvB was upregulated in response to constant exposure to sub-MIC norfloxacin.

To our knowledge, association between sub-lethal fluoroquinolone and expression of ribosomal protein operons as well as GcvB sRNA have never been reported. Collectively, these findings suggest that there are novel pathways possibly related to ppGpp levels that are involved in the adaptive response of S. sonnei towards fluoroquinolones.

Read the full text

Recommended for you

Open a chat to talk to our sales team