Sensitivity of theBurkholderia cepaciacomplex andPseudomonas aeruginosato transducing bacteriophages

Abstract

Burkholderia cepacia is now recognised as a life-threatening pathogen among several groups of immunocompromised patients. In this context, the proposed large-scale use of these bacteria in agriculture has increased the need for a better understanding of the genetics of the species forming the B. cepacia complex. Until now, little information has been available on the bacteriophages of the B. cepacia complex. Transducing phages, named NS1 and NS2, were derived from the lysogenic B. cepacia strains ATCC 29424 and ATCC 17616. The frequency of transduction per phage particle ranged from 1.0x10(-8) to 7.0x10(-6) depending on the phage and recipient strain used. The host range of NS1 and NS2 differed but in each case included environmental and clinical isolates, and strains belonging to several species and genomovars of the B. cepacia complex. The host range of both phages also included Pseudomonas aeruginosa. Some B. cepacia complex isolates were sensitive to the well-characterised P. aeruginosa transducing phages, B3, F116L and G101. The lytic activity of NS1 and NS2 was inhibited by B. cepacia lipopolysaccharide suggesting that this moiety is a binding site for both phages. The molecular size of the NS1 and NS2 genomes was approximately 48 kb.

The Promise of Bacteriophage Therapy for Burkholderia cepacia Complex Respiratory Infections

“…The goal of early BCC phage studies was not to identify phage therapy candidates, but instead to isolate generalized transducing phages that could be used for the genetic manipulation of BCC strains (Cihlar et al, 1978; Matsumoto et al, 1986; Nzula et al, 2000). Cihlar et al (1978) were the first to publish a description of a BCC phage in 1978 (Bcep781 was also isolated in 1978, but its sequence was not published until 2006; Summer et al, 2006).…”

“…This myovirus has a ∼52 kbp genome and a broad host range, infecting 46 out of 105 P. cepacia strains screened (although the identity and relatedness of these strains were not discussed). More recently, Nzula et al (2000) identified two generalized transducing phages, NS1 and NS2. These are ∼48 kbp temperate phages of B. vietnamiensis ATCC 29424 and B. multivorans ATCC 17616, respectively.…”

“…These are ∼48 kbp temperate phages of B. vietnamiensis ATCC 29424 and B. multivorans ATCC 17616, respectively. Interestingly, both CP1 and NS2 (in addition to KS5, discussed below) are temperate myoviruses of ATCC 17616, but they were found to have differing generalized transduction efficiencies and sensitivity to chloroform (Cihlar et al, 1978; Nzula et al, 2000). Similar to KS5, both NS1 and NS2 are predicted to use LPS as a receptor (Nzula et al, 2000; Lynch et al, 2010a).…”

“…Interestingly, both CP1 and NS2 (in addition to KS5, discussed below) are temperate myoviruses of ATCC 17616, but they were found to have differing generalized transduction efficiencies and sensitivity to chloroform (Cihlar et al, 1978; Nzula et al, 2000). Similar to KS5, both NS1 and NS2 are predicted to use LPS as a receptor (Nzula et al, 2000; Lynch et al, 2010a). NS1 and NS2 can infect strains with different serotypes, which may be a result of minimal phage interaction with the O-antigen or changes in the strains that were screened (Kenna et al, 2003).…”

“…NS1 and NS2 can infect strains with different serotypes, which may be a result of minimal phage interaction with the O-antigen or changes in the strains that were screened (Kenna et al, 2003). These phages also have a broad host range, particularly NS2: each could infect strains of B. cepacia , B. multivorans , B. cenocepacia , B. vietnamiensis , and P. aeruginosa (Nzula et al, 2000). Certain BCC strains were also found to be susceptible to infection by P. aeruginosa phages, specifically E79, B3, F116L, and G101.…”