Bacteriophage Felix O1, also known as enterobacteria phage O1, has been used to type Salmonella Typhi and is an excellent candidate for use in bioremedial and therapeutic applications. It has extremely high intra-species specificity and is strictly virulent in nature, unable to undergo lysogeny. To facilitate the development of the bacteriophage for use in these areas, the full sequence of the genome had been elucidated previously. In this work, identification and classification of functional coding sequences via reverse transcriptase-polymerase chain reaction was performed.

All of the 115 putative open reading frames (ORFs) studied were found to be functional. 53.0%, 9.6%, and 18.3% of the ORFs investigated were found to initiate expression early, middle or late in the lytic cycle, respectively. Expression of the remaining 19.1% ORFs was evident when the amount of total RNA was increased and when samples were taken at a later time point. Comparisons between bacteriophage Felix O1 and the phage with the most shared homologs, phage T4, revealed many similarities in times of gene expression.