Gisella Alcaraz-Bacillus Pumilus

Classification

• Domain: Bacteria

• Kingdom: Eubacteria

• Phylum: Firmicutes

• Class: Bacilli

• Order: Bacillales

• Family: Bacillaceae

Species

• Genus: Bacillis

• Species: Pumilus

Habitat Information

Organism was collected on 25 January 2015. The air temperature was 69* F. The humidity was 36%. There had been no rainfall in the previous 24 hours. The altimeter pressure (in) was 30.10. The sea level (mb) is 1019.0. The solar radiation was 15.18 MJm2. The sample was collected from an area classified as "eddy gravelly loam" and had 3 to 6% slopes. The sample was collected from the soil that was surrounding a pool of rain water in 10000 David Moore Drive Austin Tx, 78748.

Description and Significance

• Colony Morphology: Wrinkled, very tan looking colonies. Also, the colony formation is in between circular and irregular, elevation is convex, and margin is undulate.

• Cellular Morphology: Rod Shaped, Bacillus

• When spread on a plate of Gram (+) E. faecalis, it produced a slight zone of inhibition.

• Organism may be significant because there is research that leads us to believe that B. pumilus is involved in bacterial hay preservation. B. pumilus bacteria is also used for its plasmids in gene transfer systems. The proteases from B. pumilus are used in various industries. Food, chemical, detergent, and leather industries can benefit from the proteases from B. pumilus. The use of the plasmids from B. pumilus and insertion of other plasmids to the bacteria aide in various industries, and as antimicrobials and antifungals.

Genome Structure

B. pumilus consists of one circular chromosome. The circular chromosome contains around 4000 genes and 3600-3900 proteins. Also, the formation of these chromosomes allows for the potential ability for these bacteria to be used in gene transfer.

MR -23 - Forward PCR sequence:

CGCGTGAGTGATGAAGGTTTTCGGATCGTAAAGCTCTGTTGTTAGGGAAGAACAAGTGCGAGAGTAACTGCTCGCACCTT GACGGTACCTAACCAGAAAGCCACGGCTAACTACGTGCCAGCAGCCGCGGTAATACGTAGGTGGAAGCGTTGTCCGGAAT TATTGGGCGTAAAGGGCTCGCAGGCGGTTTCTTAAGTCTGATGTGAAAGCCCCCGGCTCAACCGGGGAGGGTCATTGGAA ACTGGGAAACTTGAGTGCAAAAGAAGAAAGTGGAATTCCACGTGTAGCNGTGAAATGCTTTNGTTTNTNGAAGAACTCCA NGTTTTAAGTTAANNGTGGNTGACNTNNACTCNTACANACNAANTCTGGGGAGNGAATTGAGATCCNCCCCGGGGGCAAC CCGCGGTCTTACNNTCAGCAANCGANNCGGCGTGCCCCCCTTTNACCCCANTANNTNACANATCTGCCGCTCCCTCTGTA TTATGGCGGCTGGTCACACNTTTTAATTGGAGTTTATTGTGGCANACACCAAAGGNGGAACCAGTAGCT

(The N stands for a variable.)

Cell Structure, Metabolism and Life Cycle

Like most Gram-positive bacteria, teichoic and lipoteichoic acids cover the outermost layer of the peptidoglycan plasma membrane. They play a role in adhesion to host cells and other surfaces found in the environment, as well as being major surface antigens. B. pumilus can be found in any of three life stages: sporangium, vegetative cell, or free spore. When conditions are not favorable for growth, B. pumilus will go through sporulation stage and release a spore into the environment. The stage of sporangia is between the vegetative state and a free spore in which an immature spore is kept within the cell that can undergo further sporulation if the conditions are favorable.[3] In the formation of a vegetative cell from a free spore, the spore will typically undergo germination when the conditions most favor it. An important component to the germination and resuming a appropriate growth rate is timing germination with a non-transient temperature change or nutrient availability. B. pumilus tests positive for amylase, lipase, and protease production. It has many mechanisms that include nitrate reduction, gas production formation of glucose, and acid production from a variety of carbon sources,like mannitol, glucose, and lactose. Also, B. pumilus can generate acetylbutanediol (ABD) from acetoin, as seen by a positive result for the Voges-Proskauer test.

Physiology and Pathogenesis

B. pumilus tests positive for amylase, lipase, and protease production. In a relatively recent study, the preliminary pathogenicity studies demonstrated that cell-free cultures of the organism could not cause any disease symptoms, whereas the bacterial suspensions caused severe symptoms. The pathology studies revealed that infection of GR8 could cause starch grains to shrink from normal size, and destroy the parenchyma cells by invading and propagating in them. [1]

B. pumilus has been linked to at least 3 cases of food poisoning. The symptoms that resulted from infection included dizziness, headache, chills, back pain, stomach cramps, and diarrhea. [3]

Further testing and Results from Biochemical Tests:

MR-VP (Methyl Red and Voges-Proskauer)Tests:

• No mixed acid fermentation
• Neutral end products.

Citrate Test:

• Organism can use Citrate as the only carbon source.

SIM Test:

• Cannot use Sulfur as terminal electron acceptor
• Organism is not motile
• Tryptophan is not broken down and indole is not produced.

Nitrate Test:

• Organism did not make NO2 from NO3 OR organism broke down NO3 into another nitrogenous product.
• After adding zinc solution turned red = Organism did not reduce nitrate.

Urea Test:

• Organism is not able to break down Urea to Ammonia

TSI Test:

• Red Slant/ Yellow Butt/No gas production

-Does not ferment either lactose or sucrose -Some fermentation has occurred, acid has been produced, it is a facultative anaerobe.

Decarboxylation Test:

• Arginine- Negative for Arginine decarboxylase
• Lysine- Negative for Lysine decarboxylase
• Ornithine- Negative for Ornithine decarboxylase

Phenylaline Deaminase Test:

• Tested negative, which means that this organism is not able to remove amino group from phenylalnine.

Oxidase Test :

• (-) Organism is anaerobic or facultative anaerobic.

Eosin Methyline Blue Agar (EMB):

• No growth of organism, which makes this test lead us to the conclusion that the organism is Gram Positive.

Hektoen Enteric Agar (HE):

• Determind it was a Gram Positive.
• Negative for lactose fermentation.

MacConkey Agar (MAC):

• No growth, agrees with EMB test.
• Positive for lactose fermentation.

Blood Agar Test:

• β- complete breakdown of Nutrient Agar.

Mannitol Salt Agar (MSA):

• Organism is Gram Positive.
• Negative for fermentation.

Phenylethyl Alcohol Agar (PEA):

• Growth on plate leads us to the same conclusions that the organism is Gram Positive.

Catalase Test:

• Organism is able to take hydrogen peroxide and make it less harmful.
• Tested positive for catalase.

6.5% Salt Tolerance Test:

• There was growth in the broth, which means that it was not able to grow in a high salt enviroment.

Bile Esculin Test:

• Tested positive, it is able to hydrolyze Esculin in the presence of bile.

References

[1] Peng Q., Yihui Y., and Gao Y. Bacillus pumilus, a Novel Ginger Rhizome Rot Pathogen in ChinaKey Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Scieces, Wuhan, 430071, P.R. China

[2] Chamberlain M., Chang J., and Charlat D. Bacillus pumilus. From MicrobeWiki, the student-edited microbiology resource

[3] C., Hormazabal, V., and Granum, P. “Food poisoning associated with pumilacidin-producing Bacillus pumilus in rice”. International Journal of Food Microbiology. 2007. Volume 115. p. 319-324.

Author

Page authored by Gisella Alcaraz, student of Prof. Kristine Hollingsworth at Austin Community College.