Sulfolobus

SULFOLOBUS

Soil Microbiology

BIOL/CSES 4684

This page was created by Jesse Kurylo.

ID Characteristics

- cells are 0.8 - 2 µm in diameter

- strict aerobe

- found in pH 1 - 6, cannot survive above pH 7

- temperature range is form 55 - 87° C

- most oxidize S°, but under microaerophilic conditions will also use Fe⁺² and MnO₄^-2; as electron acceptors

- capable of lithotrophic and organotrophic growth

- pilus-like and psuedopodium-like structures often found, no flagella

The image is Sulfolobus acidocaldarius. Brock page 565.

Taxonomic Description

Lithotrophic growth occurs via oxidation of sulfide or tetrathionate. The will produce sulfuric acid. Organotrophic growth occurs by oxidation of complex organic materials such as sugars, amino acids, or yeast extracts.

Sulfolobus is a crenarchaeota found under the Archaea branch in the tree of life. Unfortunately, not a lot is know about them at this time. There is a little more known in general about the Kingdom Crenarchaeota. They are defined phylogenetically, based on comparative molecular sequence analyses. They are prokaryotic and bounded by ether-linked lipid membranes which contain isoprinoid side chains instead of fatty acids. Cells range in size from cocci less than 1 µm in diameter to filaments that are over 100 µm in length. The cell shapes also range widely irregular, lobed cells and discs to almost rectangular rods or filaments. Most species posses flagella and are motile.

Metabolically, Crenarchaeota are quite diverse, ranging from chemoorganotrophs to chemolithoautotrophs. They are anaerobes, facultative anaerobes or aerobes, and many utilize sulfur in some way for energy metabolism. Several species are primary producers of organic matter, using carbon dioxide as sole carbon source, and gaining energy by the oxidation of inorganic substances like sulfur and hydrogen, and reduction of sulfur or nitrate. Others grow on organic substrates by aerobic or anaerobic respiration or by fermentation.

The most spectacular feature of the Crenarchaeota, however, is their tolerance to, and even preference for, extremes of acidity and temperature. While many prefer neutral to slightly acidic pH ranges some species flourish in very low pH's (Sulfolobus) . Optimum growth temperatures range from 75° to 105°C, and the maximum temperature of growth can be as high as 113°C (Pyrobolus). Most species are unable to grow below 70°C, although they can survive for long periods at low temperatures.

Isolation and Ecology

Sulfolobus was originally isolated form the hot springs at Yellowstone National Park. It thrives in hot, acidic, sulfur rich soil and aquatic continental environments referred to as solfataras.

To grow these organisms in the lab the media need be very selective. A recipe is available online for this very acidic media.

The first image and the image at the top of the page are geysers from Yellowstone National Park. The second image is a sulfer rich hot spring from page 562 in Brock.

Additional information on Sulfolobus is available

Madigan, Micheal T., Martinko, John M., Parker, Jack. Brock Biology of Microorganisms. Ninth edition. Upper Saddle River, NJ: Prentice Hall, 1997.

Holt, J.G., Krieg, N.R., Sneath, P.H.A., Staley, J.T., and Williams, S.T. 1994. Bergey's Manual of Determinative Bacteriology. Ninth edition. Williams and Wilkins. Baltimore, Maryland.

Websites containing information related to Sulfolobus

http://www.gbf.de/dsmz/media/med088.htm Contains information and a recipe for the Sulfolobus media

http://lsdiv.lanl.gov/LS7/crenarchaeota/ This site has a lot of good information on crenarchaeota