Phage isolation and purification

Cultures of P. putida PpG1 (OD600 = 0.3) were inoculated at a MOI = 0.01. Chloroform was added immediately after culture lysis (~4 hours) to maximise yield after insensitivity was determined. The lysate was concentrated by PEG precipitation, and purified using CsCl density gradient centrifugation as described by Sambrook and Russell [16]. Bands were extracted and dialysis ensued with modified SM buffer (100 mM NaCl, 50 mM Tris, 10 mM, 8 mM MgSO4, 10 mM CaCl2) using Amicon Ultra-15 100kDa filters. DNA extraction, phenol-chloroform extraction, and ethanol precipitation, was carried out using SDS and proteinase K as described previously [16]. DNA was purified twice prior to sequencing using the MoBio DNA Purification Kit according to the manufacturer’s instructions.