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Translation elongation is modulated by various ribosome-binding proteins. Environmental stresses, such as starvation and antibiotics, can cause stalling of bacterial ribosomes, which may alter gene expression through a transcription or translation attenuation mechanism. In P seudomonas aeruginosa, the expression of MexXY multidrug efflux system, which plays a significant role in resistance against aminoglycoside antibiotics, is controlled by a translation surveillance mechanism. Stalling of ribosome at the PA5471 leader peptide ( PA5471.1) m RNA leads to transcription of PA5471, which subsequently up-regulates the expression of MexXY. In this study, we found that mutation in a suh B gene leads to decreased susceptibility to aminoglycosides. Transcriptomic analysis revealed an up-regulation of MexXY and PA5471, which were demonstrated to be responsible for the decreased susceptibility of the suh B mutant. We further demonstrated that PA5471.1 is essential for the up-regulation of PA5471 in the suh B mutant. Co-immunoprecipitation assay revealed an interaction between SuhB and ribosome, suggesting a role of SuhB in translation. Indeed, higher amount of PA5471.1 m RNA was found to associate with ribosome isolated from the suh B mutant, indicating increased ribosome stalling. Therefore, this study identified SuhB as a novel ribosome associated protein that is involved in modulating ribosome activity. [ABSTRACT FROM AUTHOR]