Physical location of ribosome binding sites on lambda DNA.

Escherichia coli ribosomes were bound to single-stranded lambda DNA and fixed with glutaraldehyde. The complexes were visualized in the electron microscope. The positions of ribosomes bound in the immunity region and portions of the early regions between map co-ordinates 63% and 86% correspond closely to 12 known genes in these regions. Binding occurred at several sites at which genes have not been mapped. These sites probably indicate the position of unmapped lambda genes or genes not yet identified genetically. This procedure may have general applicability for mapping and other studies.