Test of Origin Site (oriC) and Terminus Site (terC) of Replication by Wavelet Analysis in Bacteria

For the significance test of the unknown parameter distributions, a non-parametric method, such as wavelet transformation analysis, is a reasonable choice. A wavelet is a waveform of effectively limited duration that has an average value of zero, and wavelet analysis is the breaking up of a signal into shifted and scaled versions of the original (or mother) wavelet. It provides a multi-scale representation of signals allowing efficient smoothing and/or extracting of basic components at different scales. The method has been used on G+C pattern occurring in genomes [6]. Unfortunately, those studies, using wavelet analysis, have provided purely qualitative results, and there was an apparent lack of quantitative results and statistical tests. This paper briefly describes to the use of wavelet transforms to analyze the signal and MonteCarlo simulation to provide confidence intervals for the result. A nonparametric method, based on a wavelet transform analysis of the GC skew, combined with Monte-Carlo simulation, is shown to be an effective method for predicating gene site and giving confidence intervals. We simulated the GC skew in S.typhi CT18 as an illustrative example.