Related Experiment Video
Updated: May 30, 2026

DNA-affinity-purified Chip (DAP-chip) Method to Determine Gene Targets for Bacterial Two component Regulatory Systems
Published on: July 21, 2014
BacPP: bacterial promoter prediction--a tool for accurate sigma-factor specific assignment in enterobacteria
Scheila de Avila E Silva1, Sergio Echeverrigaray, Günther J L Gerhardt
1Universidade de Caxias do Sul, Programa de Pós-Graduação em Biotecnologia, Av. Francisco Getúlio Vargas, 1130-CEP 95070-560, Caxias do Sul-RS, Brazil. sasilva6@ucs.br
A new bioinformatics tool, BacPP, accurately identifies Escherichia coli promoter sequences for various sigma factors. This method advances gene expression analysis beyond previous limitations.
Area of Science:
- Bioinformatics
- Molecular Biology
- Genomics
Background:
- Promoter sequences are crucial for gene expression regulation.
- Existing in silico methods for promoter recognition are limited, often focusing only on sigma-70 dependent sequences.
- A generalized bioinformatics approach for promoter identification is lacking.
Purpose of the Study:
- To develop a novel bioinformatics tool, BacPP, for accurate recognition and prediction of Escherichia coli promoter sequences.
- To differentiate promoter sequences based on their specific sigma factor.
- To provide information on upstream gene sequences associated with predicted promoters.
Main Methods:
- Development of BacPP using a novel approach based on neural networks.
- Training neural networks with known promoter sequences specific to different sigma factors.
- Extraction of weighing rules from trained neural networks to build the BacPP prediction model.
Main Results:
- BacPP achieves high accuracy in recognizing promoter sequences for specific sigma factors: σ24 (86.9%), σ28 (92.8%), σ32 (91.5%), σ38 (89.3%), σ54 (97.0%), and σ70 (83.6%).
- The tool demonstrates robust performance, maintaining 76% overall accuracy when tested on promoter sequences from other enterobacteria.
- BacPP effectively assigns sequences to their corresponding sigma factors and offers insights into upstream gene contexts.
Conclusions:
- BacPP represents a significant advancement in bioinformatics for promoter sequence analysis in Escherichia coli.
- The tool's ability to distinguish promoters by sigma factor enhances the understanding of gene regulation.
- BacPP's cross-species applicability suggests broader potential in microbial genomics research.
Related Concept Videos
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Prokaryotic Transcriptional Activators and Repressors
Transcription of prokaryotic...
Prokaryotic Transcriptional Activators and Repressors
Transcription of prokaryotic...
The Eukaryotic Promoter Region
Bacterial Transcription
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Global Regulatory Systems

