Characterization of interspecific plasmid transfer mediated by Bacillus subtilis temperate bacteriophage SP02

Abstract

Plasmid pPL1010 is a 7.0-kilobase derivatiVe of plasmid pUB110 that harbors the cohesive end site of the bacteriophage SP02 genome. Plasmid pPL1017 is a 6.8-kilobase derivative of plasmid pC194 that contains the immunity region of bacteriophage 4105 and the cohesive end site of bacteriophage SP02. These plasmids are transducible by bacteriophage SP02 at a frequency of 10-2 transductants per PFU among mutant derivatives of Bacillus subtilis 168 and have been transferred to other strains of B. subtilis and B. amyloliquefaciens by means of bacteriophage SP02-mediated transduction, with frequencies ranging from 10to 10-7 transductants per PFU. The introduced plasmids were stably maintained in nearly all new hosts in the absence of selective pressure. An exception was found in B. subtilis DSM704, which also harbored three cryptic plasmids. Plasmids pPL1010 and pPL1017 were incompatible with a 7.9-kilobase replicon native to strain DSM704. Furthermore, plasmid pPL1017 was processed by strain DSM704 into a -5.3-kilobase replicon that was compatible with the resident plasmid content of strain DSM704. The use of bacteriophage SP02-mediated plasmid transduction has allowed the identification of Bacillus strains that are susceptible to bacteriophage SP02-mediated genetic transfer but cannot support bacteriophage SP02 lytic infection.

Bacteriophage SPO2-mediated plasmid transduction in transpositional mutagenesis within the genus Bacillus

“…Strain CU3534 contains the S. faecalis transposon Tn917 inserted in the host chromosome (near citG; S. Zahler, personal communication). The prototrophic strain B. amyloliquefaciens DSM7 was obtained from Bayer A.G. (15). Media used included tryptose blood agar base (TBAB; Difco Laboratories), antibiotic medium 3 (Penassay broth [PB]; Difco), and M medium prepared for broth and solid-base cultures as previously described (13,17).…”

“…Bacteriophages and plasmids. Bacteriophages SPO2C and 4105 are spontaneous clear-plaque derivatives of the temperate bacteriophages SP02 and 4105, respectively (12,15).…”

“…Plasmid pTV1 was a generous gift from P. J. Youngman. Plasmid pPL1017 is a 7.0-kilobase (kb) derivative of plasmid pC194 that contains the immunity region of bacteriophage 4105 and the cohesive end site (cos) of bacteriophage SP02 (11,15). Derivatives of plasmid pTV1 containing the SP02 cos site region at the plasmid's unique EcoRI or PstI site had 1284 KOPEC ET AL.…”

“…Recombination-proficient strains lysogenic for SP02 and harboring SPO2 cos plasmids can be induced to yield lysates with transducing frequencies ranging from 0.5 x 10-2 to 2.0 x 10-2 transductants per PFU for plasmid-borne markers (11). Plasmid pPL1017 is a derivative of plasmid pC194 that harbors the cos site of SPO2 and the immunity region of bacteriophage 4105 (11,15).…”

“…transpose onto plasmid pPL1017, resulting in the mutagenesis of sequences borne by the plasmid. Furthermore, a Tn917-bearing plasmid was introduced into B. amyloliquefaciens by means of SP02-mediated interspecific plasmid transduction (15), and the chromosome of the new host was mutagenized.…”