title: Determination of viable Salmonellae from potable and source water through PMA assisted qPCR.
abstract: Resource constrained countries identified as endemic zones for pathogenicity of Salmonella bear an economic burden due to recurring expenditure on medical treatment. qPCR used for Salmonella detection could not discriminate between viable and nonviable cells. Propidium monoazide (PMA) that selectively penetrates nonviable cells to cross-link their DNA, was coupled with ttr gene specific qPCR for quantifying viable salmonellae in source/potable waters collected from a north Indian city. Source water (raw water for urban potable water supply) and urban potable water exhibited viable salmonellae in the range of 2.1×10(4)-2.6×10(6) and 2-7160CFU/100mL, respectively. Potable water at water works exhibited DNA from dead cells but no viable cells were detected. PMA assisted qPCR could specifically detect low numbers of live salmonellae in Source and potable waters. This strategy can be used in surveillance of urban potable water distribution networks to map contamination points for better microbial risk management.
authors.affiliation: Environmental Microbiology, Environmental Toxicology Group, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow-226001, Uttar Pradesh, India.
authors.forename: Gulshan
authors.initials: G
authors.lastname: Singh
authors.forename: Poornima
authors.initials: P
authors.lastname: Vajpayee
authors.forename: Saurabh
authors.initials: S
authors.lastname: Bhatti
authors.forename: Nirmala
authors.initials: N
authors.lastname: Ronnie
authors.forename: Nimish
authors.initials: N
authors.lastname: Shah
authors.forename: Peter
authors.initials: P
authors.lastname: McClure
authors.forename: Rishi
authors.initials: R
authors.lastname: Shanker
mesh_terms: D001386:Azides / Q000737:chemistry; D060766:Drinking Water / Q000382:microbiology*; D050296:Microbial Viability; D011419:Propidium / Q000031:analogs & derivatives / Q000737:chemistry; D060888:Real-Time Polymerase Chain Reaction; D012475:Salmonella / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D014867:Water; D014871:Water Microbiology
chemical_list: D001386:Azides; D060766:Drinking Water; C533957:propidium monoazide; D014867:Water; D011419:Propidium