Identification of Bacteria found in Winogradsky Columns

 A collaborative lab exercise for Science Majors (BIO 416/422) & Non-Science Majors (ENV 106)

Drs. Catalina Arango & Brian Forster

Since Fall 2013, Drs. Arango & Forster have used a Winogradsky column lab exercise as a means of having science majors & non-science majors work together to learn the collaborative nature of science while identifying bacteria enriched in the column.

Winogradsky column is a miniature ecosystem that can be utilized to enrich for bacteria (allow them to grow more abundantly).  Two classes of bacteria that can be enriched include:

  • Phototrophs: Organisms that use light as an energy source
  • Chemotrophs: Organisms that use chemicals as an energy source

Environmental samples of soil and water are packed into a column and incubated for several weeks under light.  Over time, an O2 and H2S gradient is generated due to the metabolisms of bacteria (Fig 1 below).  The column promotes growth of organisms at various depths corresponding to O2 and H2S concentrations.  Over time, colors begin to form in the column.  These colors are due to the photosynthetic pigments that are being produced by phototrophs to capture light energy.

Figure 1.  Winogradsky Column after several weeks of incubation with labeled O2 and H2S gradients.  Photo credit: Jasmine Ramirez, Biology MS ’15

 

View our Winogradsky Columns with our Live Camera Feed: 

Click here to view Live Feed

NOTE:

This live feed is best viewed using Firefox, and the latest version of Java.  If you are using Internet Explorer on a Microsoft Windows computer, you may see a warning at the top of your web browser prompting you to allow a D-Link add-on to run.  If this happens, click on the warning and click “Run Add-on.”  Then click “Run” at the “Internet Explorer – Security Warning dialog window.”  For all browsers, you must have Java enabled.

Winogradsky Columns Collaborative Report Site: 

Click HERE to access the Collaborative Report site.  (your  lab instructor will announce in class the password to edit the site with your group’s data)