environmental samplesuncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.uncultured Citrobacter sp.