Rhamnose-inducible expression constructs are described. The expression constructs may be either episomal or chromosomal and may include at least one rhamnose-inducible regulatory element expressing a regulatory protein and at least one promoter that is inducible by the regulatory protein. An open reading frame expressing a protein of interest may be placed under control of the promoter. Also described are optimized Shine-Dalgarno sequences for use with the promoter.