The cytocrome c nitrite reductase (ccNir) isolated from the sulphate-reducing bacterium Desulfovibrio desulfuricans ATCC 27774 is a hetero-oligomeric complex composed by two subunits (61 KDa and 19 KDa), encoded by genes nrfA and nrfH, respectively. We report the use of bioinformatic predictive models in order to access of ccNir most relevant topological characteristics, namely signal peptides and signal anchors. We made used of a combined method of SignalP V2.0 (SignalP-HMM and Signal-NN) in association with TMHMM 2.0 for the prediction of the presence and location of signal peptide cleavage sites, to discriminate between cleavable signal peptides and N-terminal transmembrane anchors segments and, to predict of transmembrane helices.