Helicobacter pylori is a pathogenic bacterium that colonizes the human epithelia, causing duodenal and gastriculcers, and gastric cancer. The genome of H. pylori 26695 has been previously sequenced and annotated. In addition, two genome-scale metabolic models have been developed. In order to maintain accurate and relevant information on coding sequences (CDS) and to retrieve new information, the assignment of new functions to Helicobacter pylori 26695s genes was performed in this work. The use of software tools, on-line databases and an annotation pipeline for inspecting each gene allowed the attribution of validated EC numbers and TC numbers to metabolic genes encoding enzymes and transport proteins, respectively. 1212 genes encoding proteins were identified in this annotation, being 712 metabolic genes and 500 non-metabolic, while 191 new functions were assignment to the CDS of this bacterium. This information provides relevant biological information for the scientific community dealing with this organism and can be used as the basis for a new metabolic model reconstruction.This work was supported by the project FCOMP-01-0124-FEDER-009707, entitled HeliSysBio molecular Systems Biology in Helicobacter pylori (Ref.: FCT PTDC/EBB-EBI/104235/2008). Daniela Correia is grateful for financial support from the FCT (PhD grant: SFRH/BD/47596/2008)
