Bacteria and Fungi in Carnivorous Pitcher Plants Help Break Down Chitin from Insect Prey
Mentor 1
Erica Young
Location
Union Wisconsin Room
Start Date
29-4-2016 1:30 PM
End Date
29-4-2016 3:30 PM
Description
The pitcher plant Sarracenia purpurea is a carnivorous plant which traps insect prey in modified leaves which fill with rainwater. Prey is broken down and nutrients released through the activity of hydrolytic enzymes produced by bacteria, fungi and other organisms. One enzyme is chitinase which breaks down the chitin within insect exoskeletons. Bacterial enzyme activities have been reported. Our objective was to determine whether fungi also contribute to chitinase activity in pitcher water. The experiment was performed on two Sarracenia purpurea plants in the UWM greenhouse and chitinase enzyme activity was measured in pitcher water following different addition treatments. Dead fruit flies were added as a source of chitin-containing prey, and treatments included controls with just flies, and additions of antibiotics to inhibit bacteria, fungicide to inhibit fungal growth, or both. Over a 14 days, water samples were collected and analyzed with a fluorometric chitinase activity assay method, and changes in chitinase enzyme activity over time in each of the treatments examined. One day after addition of flies, chitinase activity in pitcher water increased by over 600%. However inhibition of bacteria reduced this increase to only 92% of the increase in the control and addition of fungicide suppressed chitinase activity to 74% relative to the control. At the end of 14 days, chitinase activity of the control decreased by 75% from its original increase. The group treated with antibiotics experienced a greater decline and the activity of the fungicide treated group was also drastically reduced from the initial activity spike. These findings suggest that along with the chitinase activity from bacteria in pitchers, fungi also contribute to the net chitinase activity within pitcher water, helping to degrade insect chitin, releasing nitrogen for plant uptake.
Bacteria and Fungi in Carnivorous Pitcher Plants Help Break Down Chitin from Insect Prey
Union Wisconsin Room
The pitcher plant Sarracenia purpurea is a carnivorous plant which traps insect prey in modified leaves which fill with rainwater. Prey is broken down and nutrients released through the activity of hydrolytic enzymes produced by bacteria, fungi and other organisms. One enzyme is chitinase which breaks down the chitin within insect exoskeletons. Bacterial enzyme activities have been reported. Our objective was to determine whether fungi also contribute to chitinase activity in pitcher water. The experiment was performed on two Sarracenia purpurea plants in the UWM greenhouse and chitinase enzyme activity was measured in pitcher water following different addition treatments. Dead fruit flies were added as a source of chitin-containing prey, and treatments included controls with just flies, and additions of antibiotics to inhibit bacteria, fungicide to inhibit fungal growth, or both. Over a 14 days, water samples were collected and analyzed with a fluorometric chitinase activity assay method, and changes in chitinase enzyme activity over time in each of the treatments examined. One day after addition of flies, chitinase activity in pitcher water increased by over 600%. However inhibition of bacteria reduced this increase to only 92% of the increase in the control and addition of fungicide suppressed chitinase activity to 74% relative to the control. At the end of 14 days, chitinase activity of the control decreased by 75% from its original increase. The group treated with antibiotics experienced a greater decline and the activity of the fungicide treated group was also drastically reduced from the initial activity spike. These findings suggest that along with the chitinase activity from bacteria in pitchers, fungi also contribute to the net chitinase activity within pitcher water, helping to degrade insect chitin, releasing nitrogen for plant uptake.
