Operon Estimates

NOTE: If you are looking for predicted operons, rather than operon estimates, look under “Predicting Transcription Units.”

These tables present estimates on the proportion of genes that should be in operons given the genome organization of the Prokaryotic genomes available at the time of calculation at NCBI’s RefSeq.

The estimates are based on the number and size (in number of genes) of directons, stretches of adjacent genes in the same strand with no intervening gene in the opposite strand.

The columns in the tables are:

• Genome
• Size (Mbp)
• Number of annotated genes
• Number of directons
• Number of directons with only one gene
• Proportion of genes in operons
• Proportion of operon junctions
• Total transcription units

For deeper explanations and citation see:

Moreno-Hagelsieb G (2006) Operons Across Prokaryotes: Genomic Analyses and Predictions 300+ Genomes Later. Current Genomics 7:163-170

Cherry JL (2003) Genome size and operon content. J Theor Biol 221:401-410