Figure 1

Random genome compared to sequenced bacterial genomes. Comparisons between 581 sequenced bacterial and archaeal chromosomes and plasmids with a random 5.3 mbp DNA sequence with 50% GC content. The comparisons were performed to test the reliability of different oligonucleotide based statistical measures consisting of di- to hexanucleotide ZOMs, tetranucleotide ROFs and MCMs. The chromosomes and plasmids, represented as points along the horizontal axis, were correlated with the random DNA sequence, with the corresponding correlation scores on the vertical axis, and sorted by increasing AT content from left to right. Higher correlation scores means better match. In (A) all chromosomes and plasmids were compared using di- to hexanucleotide ZOMs, while in (B) they were compared using tetranucleotide ROFs and MCMs, with tetranucleotide ZOMs included as reference. It can be observed that dinucleotide ZOMs achieve surprisingly high correlation scores (A) while hexanucleotide ZOMs show no correlation at all. Tetranucleotide ROFs (B) achieves slightly higher correlation values than both tetranucleotide MCMs and ZOMs.