Thymineless bacteriophage induction in Staphylococcus aureus. I. High-frequency transduction with lysates containing a bacteriophage related to bacteriophage phi 11

Abstract

A thymine-requiring mutant of Staphylococcus aureus, strain 8325(PIM)thy, undergoes prophage induction and lysis after thymine starvation. Four different phages were isolated from the lysate in low titers, among which was a phage designated 414, which differs from phage 441 in its immunity locus. The thymineless induced lysates of strain 8325(PIn8)thy transduce the penicillinase plasmid at high frequency (10-1), whereas transduction of chromosomal markers is inefficient. A plasmid-cured derivative of strain 8325(PI,.m)thy is also lysed by thymine starvation and can be used for high-frequency transduction of other plasmids. Reconstitution of a strain of S. aureus that responds to thymine starvation was only partially successful, but this system can effectively be used to transduce plasmids or plasmid derivatives. on July 7, 2020 by guest

Transformation in Staphylococcus aureus: role of bacteriophage and incidence of competence among strains

“…e Less than the given frequency denotes that no transfectants were detected. nism (lysogenic for 4)11, 412, and 4)13) contains a predominance of 4)12 (26), we expected the medium from 8325(N)nov also to contain a predominance of 4)12; however, because of the high competence-conferring activity of the 8325(N)nov growth medium, a significant number of free 4)11 virions also were expected. However, when 8325(N)nov growth medium was treated with 4)12 antiserum at 35°C for 30 min and assayed for lytic activity toward 8325-4, only 10 PFU/ml could be detected ( Table 3).…”

Role of bacteriophage in the acquisition of competence for genetic transformation and transfection in Staphylococcus aureus and related studies

“…Thus, it was concluded that the prophage is necessary for the expression of competence in strain 8325 (Sjostrom et al, 1973). Besides #11, only lysogens carrying the closely related phages 83A (Sjostrom and Philipson, 1974) and 4il4 (Rudin and Lindberg, 1975) could demonstrate competence. The origin of the latter phage is unclear, but phages <J)11 (Novick, 1967), 83A (Wentworth, 1963) and (j)14 (Rudin and Lindberg, 1975) all belong to the serological group B; therefore, they all are morphologically related.…”

“…Besides #11, only lysogens carrying the closely related phages 83A (Sjostrom and Philipson, 1974) and 4il4 (Rudin and Lindberg, 1975) could demonstrate competence. The origin of the latter phage is unclear, but phages <J)11 (Novick, 1967), 83A (Wentworth, 1963) and (j)14 (Rudin and Lindberg, 1975) all belong to the serological group B; therefore, they all are morphologically related. Sjostrom et al (1973) also demonstrated that vegetative (j)ll could confer competence to 8325-4.…”

“…Because <l)13-lysogens are susceptible to lysis by ^11, but (j)12-lysogens are immune to lysis by both <))12 and <|)13 (Novick, 1967), it appeared that the 8325nov-142 growth medium contained a predominance of infectious #2 particles. Furthermore, (|)13 is not susceptible to neutralization with antiserum directed against <))12 (Rudin and Lindberg, 1975). Therefore, the approximately 10 pfu/ml remaining after neutralization with (j)12-antiserum or when 8325-4(^12) was used as an indicator were assumed to be either (|)11 or an unidentifiable serolog ical group B phage.…”

“…The competence-conferring activity of phages 55 and 80a was neutralized by preincubation at 35 C for 10 min with 10% (jill-antiserum (group B; Novick, 1967); the competence-conferring activity of phage 3A was neu tralized by preincubation with 10% '|>12-antiserum (serological group A; Rudin and Lindberg, 1975) In addition, none of the bacterial strains that were used to propagate the phages were resistant to novobiocin (10 yg/ml).…”