E. coli RNA 5' ends
RNA was purified from E.coli grown in LB with aeration to an  OD600 of 0.7. Ribosomal RNA was removed. RNA was treated with Tobacco Acid Pyrophosphatase to convert 5' triphosphates to monophosphates. An RNA oligonucleotide was ligated. cDNA was made using a primer with 9 random 3' end bases. The library was amplified by 3 rounds of PCR.