Sequence of a DNA injection gene from Salmonella typhimurium phage P22. Nucleic Acids Res

In the Salmonella phage P22, the presence of three structural proteins in the phage particle, gp7, gpl6, and gp20 is required for successful phage DNA injection (1, 2). The genes coding for these proteins are contiguous, occupy about 4 kilobases in the late operon of P22 and are located between the imml region and genes which specify other capsid proteins. The specific function of any one of the DNA injection gene products remains obscure. The sequence of these genes will prove useful toward the study of DNA injection in this virus. The sequences of two of these genes, gene 7 and gene 16 have recently been reported (3, 4). Here we report the sequence of gene 20. Gene 20 is flanked on it's 5 ' side by gene 7 and by gene 16 on its 3 ' side. Sequencing of the gene was performed off of both strands, employing the dideoxy chain termination method (5). The sequence reveals a single 1416 base pair ORF which coul