Bacteriophage P22-mediated specialized transduction in Salmonella typhimurium: identification of different types of specialized transducing particles

Abstract

Wfld type K. Sanderson; 45 araB9 P. Margolin; 27 JK433 srl-2::tet-517 strAr recAl a J. Roth JK245 leuD798ara gal-205proA575 P. Margolin JK74 leuD798ara fol-101 proAB47b J. Kemperc JK486 leuD798ara fol-101 proAB47 (P22sieAl h21) Lysogenaof JK74 JK79 leuD798ara fol-101 proB25 J. Kemperc JK447 leuD798ara fol-101 proB25 (P22tsc230 sieABI m3) Lysogenaof JK79 JK436 leuD798ara fol-101 proB25 srl-2::tet-517 strA' recAl Transductiona of JK79 by phage on JK433 JK450 leuD798ara fol-101 proB25 srl-2::tet-517 strAr recAl Lysogen' of JK436 (P22tsc230 sieAB1 m3) JK80 leuD798ara fol-101 proCiIOb J. Kemper' JK446 leuD798ara fol-101 proCIO srl-2::tet-517 strAr recAl Transductiona of JK80by phage on JK433 JK1394 leuD798ara supQ394 J. Kemper, 22 JK367 leuD798ara supQ394 (P22tsc229) Lysogen' of JK1394 JK480 leuD798ara supQ394 (P22tsc229 int3) Lysogen" of JK1394 a For origin and construction of these strains, see the text. bproAB47 and proCIO mutant strains were isolated by Demerec and obtained through K. E. Sanderson. "The construction of recombinant strains, integrating the leuD798ara mutation into the genome of different complex strains, utilized the fol-101 marker (conferring resistance to trimethoprim), which is cotransducible with the ara and leu operons (22).

Bacteriophage P22-mediated specialized transduction in Salmonella typhimurium: high frequency of aberrant prophage excision

“…1. Details of characterization and experimental identification of various types of transducing particles are presented in the accompanying paper (34).…”

Screening for highly transduced genes inStaphylococcus aureusreveals both lateral and specialized transduction

“…Therefore, though both specialised and lateral transduction could potentially transfer Tn_1849, which sits close to the prophage (~8000 kb), Tn_1797 sits >39 kb downstream of the ϕ11 prophage, nearly a full phage genome length away, so is unlikely to be transferred by specialised transduction. Furthermore, the original study reporting lateral transduction found that a marker 5 kb downstream of the integrated phage was transferred solely by lateral transduction and the researchers did not see any specialised particles containing this region, suggesting all our downstream transfer can be attributed to lateral transduction (15,17). This notion is supported by the pattern of bacterial DNA sequences obtained from the sequencing of induced phage lysates that indicates extensive packaging of bacterial DNA downstream of the integrated phage.…”

“…The study identified that this effect was unidirectional from the pac site and so the region upstream of the phage was not transferred (15). Lateral transduction has only been shown to occur with pac prophages that have been induced and does not occur when a phage infects and undergoes the lytic cycle (16,17).…”

DNA packaging initiation of Salmonella bacteriophage P22: determination of cut sites within the DNA sequence coding for gene 3

“…DNA preparations, end labeling, and sequencing. Phage particles were purified by a discontinuous (1.3 and 1.7 g/cm3) and a continuous CsCl gradient (32,000 rpm, 24 h, Beckman Ti5O rotor). DNA was prepared by two phenol extractions and extensive dialysis in 10 mM Tris-hydrochloride-0.1 mM EDTA (pH 8.0).…”

“…The position of these headful cuts is not restricted to P22-specific DNA sequences (45,46). In excision-defective lysogens, a packaging series initiated at prophage sequences will proceed into bacterial DNA sequences and form transducing particles (23,24,38,47).…”