Located on the upper part of the platform of the 30S subunit, where it bridges several disparate RNA helices of the 16S rRNA. Forms part of the Shine-Dalgarno cleft in the 70S ribosome, where it interacts both with the Shine-Dalgarno helix and mRNA. Part of the 30S ribosomal subunit. Interacts with proteins S7 and S18. Binds to the C-terminus of IF-3; however exactly how IF-3 interacts with the 30S subunit is unclear. May contact the C-terminus of Era. Belongs to the universal ribosomal protein uS11 family.