The Loop 2 Region of Ribosomal Protein uS5 Influences Spectinomycin Sensitivity, Translational Fidelity, and Ribosome Biogenesis.

Ribosomal protein uS5 is an essential component of the small ribosomal subunit that is involved in subunit assembly, maintenance of translational fidelity, and the ribosome's response to the antibiotic spectinomycin. While many of the characterized uS5 mutations that affect decoding map to its interface with uS4, more recent work has shown that residues distant from the uS4-uS5 interface can also affect the decoding process. We targeted one such interface-remote area, the loop 2 region (residues 20 to 31), for mutagenesis in Escherichia. coli and generated 21 unique mutants. A majority of the loop 2 alterations confer resistance to spectinomycin and affect the fidelity of translation. However, only a minority show altered rRNA processing or ribosome biogenesis defects.