Bacillus stearothermophilus NEUF2011

Geobacillus stearothermophilus

Classification:

Higher Order taxa:

Kingdom: Bacteria

Phylum: Firmicutes

Class: Bacilli

Order: Bacillales

Family: Bacillaceae

Species:

Geobacillus stearothermophilus.

Description and Significance:

Geobacillus stearothermophilus is a rod-shaped, Gram-positive, spore forming bacterium. In addition, this bacterium is motile, strictly aerobic, and both catalase and oxidase positive. G. stearothermophilus grow in temperatures ranging from 30-75 degrees C, with an optimal growth temperature at 55°C. This thermophile can be found in warm eniromentments including: sand, ocean vents and hot springs. It has been observed to have to survived temperatures as high as 130 degrees C. Clinically, it is extremely significant because it is used to used to verify that laboratory sterilization processes are working properly. Both biological and chemical indicators are used to determine the presence of G. stearothermophilus' spores on surfaces that have undergone a sterilization process.

Partly because of its resilence, G. stearothermophilus is often the cause of food spoilage. [1]

Genome Structure:

Geobacillus stearothermophilus has sixty-four genes that were successfully mapped in 1990 by Vallier and Welker of Northwestern University [2]. Their findings indicate that the genetic makeup of the G. stearothermophilus and the genetic makeup of a closely related species, Geobacillus subtilis, are very similar, with some important differences [2].

Cell Structure and Metabolism:

Since Geobacillus stearothermophilus is a Gram-positive bacteria, it has both an inner and outer membrane [3]. The cell surface of this microbe contains a capsule, a S-layer, several layers of peptidoglycan, and proteins on the outer membrane. The genus Bacillus have S-layers, which are crystalline layers of surface proteins and like the S-layers of other bacteria, the role of these S-layers is unknown but thought to be connected to the adherence of the bacterial cell [3]. The capsules of Geobacillus stearothermophilus are easily observed using light microscopy especially if this bacteria is prepared on growth media that allows for heavy capsule production [3]. The cell wall contains a peptidoglycan that contains DAP or meso-diaminopimelic acid and this bacterial species has a substantial amount of teichoic acids bonded to muramic acid residues [3].

Ecology:

This thermophile and is widely distributed in soil, hot springs and ocean sediment.

Pathology:

Is it pathogenic, which host, what symptoms? Current Research Summarize at least two research articles

Cool factor:

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References:

[1] NAZINA (T.N.), TOUROVA (T.P.), POLTARAUS (A.B.), NOVIKOVA (E.V.), GRIGORYAN (A.A.), IVANOVA (A.E.), LYSENKO (A.M.), PETRUNYAKA (V.V.), OSIPOV (G.A.), BELYAEV (S.S.) and IVANOV (M.V.): Taxonomic study of aerobic thermophilic bacilli: descriptions of Geobacillus subterraneus gen. nov., sp. nov. and Geobacillus uzenensis sp. nov. from petroleum reservoirs and transfer of Bacillus stearothermophilus, Bacillus thermocatenulatus, Bacillus thermoleovorans, Bacillus kaustophilus, Bacillus thermoglucosidasius and Bacillus thermodenitrificans to Geobacillus as the new combinations G. stearothermophilus, G. thermocatenulatus, G. thermoleovorans, G. kaustophilus, G. thermoglucosidasius and G. thermodenitrificans. Int. J. Syst. Evol. Microbiol. 2001, 51, 433-446.

[2] Vallier, H. & Welker, N. E. (1990). Genetic map of the Bacillus stearothermophilus NUB36 chromosome. J Bacteriol 172, 793–801.

[3] Todar, Kenneth. "Surface Structure of Bacillus." Textbook of Bacteriology. Madison, Wisconsin: , 2008. Web. 5 10, 2011.