Fig. 2.

From β-barrel score to probability. (A) The probability that a particular β-barrel score is a positive prediction can be estimated from an assessment of the PPV and a function of the arbitrary β-barrel score for a given dataset. The dataset used to assess the PPV of the β-barrel score included the annotated genes from an E. coli chromosome. There were 40 TMBBs and 2378 non-TMBBs identified out of 5253 total sequences (see the text). Proteins annotated as hypothetical, putative, or predicted were excluded. The PPV was plotted as a function of β-barrel score and was fit with a sigmoidal function. (B) Histogram of β-barrel probability for the E. coli O157 genome. Based on our previous work, a protein with probability value above 0.28 (β-barrel score above 45) is a strong candidate TMBB