Molecular characterization of a prophage of Salmonella enterica serotype Typhimurium DT104

Abstract

Isolates of the Salmonella enterica serotype Typhimurium definitive phage type (DT104) were found to contain the same prophage (designated phage ST104). The complete sequence of the DNA genome of prophage ST104 was determined. The entire DNA sequence consisted of 41,391 bp, including 64 open reading frames, and exhibited high similarity to P22 and to phage type conversion phage ST64T.

FIG. 1.

Electrophoresis of endonuclease digests of phage DNA. Phage DNA was digested with EcoRI and subsequently separated at 10 mV cm⁻¹ in a 0.8% agarose gel prepared with 89 mM Tris-2.5 M EDTA-89 mM boric acid. Lanes (FAFLP profiles are in parentheses): M, 1-kb ladder; 1, U1 (A2); 2, U2 (A2); 3, U3 (A2); 4, U4 (A2); 5, U5 (A2); 6, U6 (A1); 7, U7 (A2); 8, U8 (A2); 9, U9 (A1); 10, U17 (A2); 11, U18 (A1); 12, U20 (A1); 13, U1 (A1); 14, NET57 (A1); 15, NET2 (A2); 16, NET8 (A3); 17, H6(A4); 18, NET25 (B1); 19, NET26 (B1); 20, KT1 (B2); 21, KT2 (B2); 22, N78 (B2); 23, NET55 (B2); 24, N59 (B5); 25, NET37 (B5); 26, N34 (B5); 27, N79 (B5); 28, N81 (B5); 29, NET48 (B5); 30, NET52 (B6); 31, NET31 (B2); 32, NET40 (C1); 33, KT3 (C1); 34, 478 (B4); 35, N48 (C5).

FIG. 2.

Schematic illustration of the ST104 genome. The predicted ORFs are illustrated. ORFs with a rightward orientation are above the black line; ORFs with a leftward orientation are below the line. The map was opened adjacent to a stem-loop structure located between gene 9 and gtrC as reported in the sequence of P22 (16).