Figure 3-3: Top:> Genome map of phage Sfi21 as found in the extracellular phage particle. The individual phage modules as determined by bioinformatic analysis are marked with the brackets above the map. The arrows below the map indicate the transcripts, green: early; blue: middle, red: late transcripts. The mRNA length in kb is indicated by the numbers above the arrows, 5’ start sites determined by primer extension analysis is marked by a P in a circle. The width of the arrow indicates the strength of the autoradiographic signal in the Northern blots. The wavy lines indicate smeared hybridization results with a sharp upper end (48). Bottom: Genome maps of S. thermophilus prophages O1205 and Sfi21 as they are integrated in the bacterial chromosome. The arrows under the map mark the transcribed prophage genes (45). Note that the transcription of the prophages is limited to the regions near both attachment sites.