Geochemistry & Ecology of Red Mat Systems (GERMS)

Undergraduate Summer Research Program

 

Week Three – Microscopy, Enumeration, and

Digital Imaging: Imperial Runoff-Green

 

Elizabeth Jacobsmuhlen

 

 

Mat Layer Processing:

Site: Imperial Runoff-Green

Image – Visible Light:

10X

40X

 

Image – F Fluorescence:

10X

40X

 

Image – R Fluorescence:

10X

40X

 

Grid-Based Counts:

Example of a filament.

Total number

of filaments on the entire grid: 26.

 

 

 

 

 

 

 

 

 

Chemical Analysis of Acid-Digested Samples for Metal Assessment

 

Specific Post-Acid Digestion Results: (Imperial-Green):

Aluminum (mg/L)

0.007

Copper (mg/L)

0.00

Total Iron (mg/L)

0.06

Manganese

Not performed

Zinc (mg/L)

0.52

 

Pigment Analysis

Methanol Extraction:

Methanol Extraction Procedure:

The supernatant has been removed and the cells were re-suspended with methanol.  This is the part of the procedure where the tubes are placed under foil and on ice (10-30 minutes) in order for the methanol to “extract” the pigments from the sample present.

 

Methanol Extraction Results (Green):

Low (nm)

High (nm)

664

768

 

 

In vivo Bead-Beating:

In Vivo Bead-Beating Procedure:

This is the machine that performs the “beating” part of the bead-beating procedure.

In Vivo Bead-Beating Results (Green):

Low (nm)

High (nm)

673

794

 

 

Discussion:

            The absorption properties can be compared with the “Common Bacteriochlorophyll Absorption Properties” table listed in Week One of the protocol.  The microscopy images, listed above, taken under different light sources are also an indication of what organisms are present in the sample.  Chlorophylls –  assocaiated with oxygenic phototrophs (plants, Cyanobacteria) – fluoresce in both F and R.  While green bacteriochlorophylls – associated with some anaoxygenics – fluoresce slightly in R, but not in F.  And finally, red bacteriochlorophlls – associated with some anoxygenics – do not fluoresce in F or R.