Indeed, these mega-enzymes were never observed in exhaustive analyses of the S. coelicolor proteome (Hesketh et al., 2002). In any case, our findings are reminiscent of the well-documented phenomenon in Streptomyces bacteria wherein point mutations LBH589 that perturb the quaternary structure and/or function of the ribosome enhance antibiotic production (Wang et al., 2008). We propose that disruption of lepA could be a strategy for engineering
Streptomyces strains to overproduce clinically useful antibiotics (Vinci & Byng, 1999). The authors thank Dr Govind Chandra from the John Innes Centre for providing a list of genes in S. coelicolor ranked by size. Brown University is gratefully acknowledged for financial support. A.B.-N. was supported by Brown University Undergraduate Teaching and Research Assistantships in 2007 and 2008. “
“A bacteriophage ΦBP infecting Paenibacillus polymyxa CCM 7400 was isolated from culture lysate. Electron microscopy of lysate samples revealed the presence of bacteriophage particles with polyhedral heads 56 nm in diameter and flexible noncontractile
tails 144 nm in length. The profile of ΦBP structural proteins resembles that of other bacteriophages. The ΦBP genome consists of double-stranded DNA of 43-kbp size. Homology search PFT�� in vitro of sequenced DNA fragments from EcoRI digest revealed regions with significant similarity to other known bacteriophage genes. Regions similar to phage terminase genes were identified within the 1.2-kbp fragment. Clomifene Three lytic genes, two holin genes and one endolysin gene were identified within the 2.5-kbp fragment. We tested the isolates of P. polymyxa CCM 7400 for the
presence of phage DNA on bacterial chromosome using PCR amplification with primers derived from proposed terminase and holin gene sequences. We confirmed the presence of ΦBP DNA on P. polymyxa chromosome by Southern hybridization. The bacteriophage ΦBP was capable of causing lysis of a P. polymyxaΦBP lysogen despite the presence of the phage DNA on bacterial chromosome. Therefore, we concluded that ΦBP was a virulent mutant phage. The Gram-positive bacterial species Paenibacillus polymyxa (formerly Bacillus polymyxa, reclassified by Ash et al., 1993–1994) was isolated from different soils, rhizospheres and plant roots. Strains of P. polymyxa are phenotypically and genetically very heterogeneous (Mavingui et al., 1992; Guemouri-Athmani et al., 2000; von der Weid et al., 2000; da Mota et al., 2002). They can play different roles in natural environments, for example effective plant growth-promoting rhizobacteria. Many of them are nitrogen fixers (Grau & Wilson, 1962; Nelson et al., 1976; Wullstein et al., 1979; Seldin et al., 1983), some produce phytostimulators such as auxin metabolites (Lebuhn et al., 1997) and cytokinins (Timmusk et al., 1999), and some act as biocontrol agents (Timmusk et al., 2005; Haggag & Timmusk, 2008). Many strains of P.