Bacillus cereus biol 2402

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Classification

Domain: Bacteria

Phylum: Firmicutes

Class: Bacilli

Order: Bacillales

Family: Bacillaceae

[Others may be used. Use NCBI link to find]

Species

Genus: Bacillus

Species Group: Bacillus cereus group

NCBI: Taxonomy

Habitat Information

Describe the location and conditions under which the organism was isolated. The dirt sample that the B. cereus came from was collected on September 3, 2015 in Lakeway, Texas. The dirt was in a shady area underneath some trees between a creek and a small field. It was 91 degrees Fahrenheit, 44% humidity, and had not rained in the past 24 hours. The dirt was collected from about 2 inches below the surface. Approximate grid coordinates from the NRCS soil map are 3359230 x 598060. Soil type according to the NRCS soil map is volente silty clay loam, 1 to 8% slopes.

Description and Significance

Describe the appearance (colonial and cellular), possible antimicrobial activity etc. of the organism, and why the organism might be significant.

Colony Appearance: Matte, white, flat colonies with irregular to lobate margins.

Cellular appearance: Rod-shaped, endospore forming, and Gram-positive.

Genome Structure

Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? Include S Ribosomal sequence that you obtained from PCR and sequencing here.

Through PCR, we determined that our soil organism's DNA sequence is:

"Forward sequence:"

ACGGAGCACGCCGCGTGAGTGATGAAGGCTTTCGGGT CGTAAAACTCTGTTGTTAGGGAAGAACAAGTGCTAGTTGAATAAGCTGGCACCTTGACGGTACCTAACCAGAAAGCCACG GCTAACTACGTGCCAGCAGCCGCGGTAATACGTAGGTGGCAAGCGTTATCCGGAATTATTGGGCGTAAAGCGCGCGCAGG TGGTTTCTTAAGTCTGATGTGAAAGCCCACGGCTCAACCGTGGAGGGTCATTGGAAACTGGGAGACTTGAGTGCAGAAGA GGAAAGTGGAATTCCATGTGTAGCGGTGAAATGCGTAGAGATATGGAGGAACACCAGTGGCGAAGGCGACTTTCTGGTCT GTAACTGACACTGAGGCGCGAAAGCGTGGGGAGCAAACAGGATTAGATACCCTGGTAGTCCACGCCGTAAACGATGAGTG CTAAGTGTTAGAGGGTTTCCGCCCTTTAGTGCTGAAGTTAACGCATTAAGCACTCCGCCTGGGGAGTACGGCCGCAAGGC TGAAACTCAAAGGAATTGACGGGGGCCCGCACAAGCGGTGGAGCATGTGGTTTAATTCGAAGCAACGCGAAGAACCTTAC CAGGTCTTGACATCCTCTGAAAACCCTAGAGATAGGGCTTCTCCTTCGGGAGCAGAGTGACAGGTGGTGCATGGTTGTCG TCAGCTCGTGCCGTGAGATGTCATANNNTNGTTTTCC

"Reverse Sequence:"

ACCTGTCACTCTGCTCCCGAAGGAGAAGCCCTATCTCTAGGGTTTTCAGAGGATGTCAAGACCTGG TAAGGTTCTTCGCGTTGCTTCGAATTAAACCACATGCTCCACCGCTTGTGCGGGCCCCCGTCAATTCCTTTGAGTTTCAG CCTTGCGGCCGTACTCCCCAGGCGGAGTGCTTAATGCGTTAACTTCAGCACTAAAGGGCGGAAACCCTCTAACACTTAGC ACTCATCGTTTACGGCGTGGACTACCAGGGTATCTAATCCTGTTTGCTCCCCACGCTTTCGCGCCTCAGTGTCAGTTACA GACCAGAAAGTCGCCTTCGCCACTGGTGTTCCTCCATATCTCTACGCATTTCACCGCTACACATGGAATTCCACTTTCCT CTTCTGCACTCAAGTCTCCCAGTTTCCAATGACCCTCCACGGTTGAGCCGTGGGCTTTCACATCAGACTTAAGAAACCAC CTGCGCGCGCTTTACGCCCAATAATTCCGGATAACGCTTGCCACCTACGTATTACCGCGGCTGCTGGCACGTAGTTAGCC GTGGCTTTCTGGTTAGGTACCGTCAAGGTGCCAGCTTATTCAACTAGCACTTGTTCTTCCCTAACAACAGAGTTTTACGA CCCGAAAGCCTTCATCACTCACGCGGCGTTGCTCCGTCAGACTTTCGTCCATTGCGGAAGATTCCCTACTGCTGCCNCNC GTANAGTACTGG

Cell Structure, Metabolism and Life Cycle

Interesting features of cell structure; how it gains energy; what important molecules it produces.

Physiology and Pathogenesis

Biochemical characteristics, enzymes made, other characteristics that may be used to identify the organism; contributions to environment (if any).
If relevant, how does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

B. Cereus is motile, catalase positive, able to ferment glucose, unable to ferment lactose, able to reduce nitrate to non gaseous nitrogenous compounds, produces amylase, and has alpha hemolytic activity.

We tested our sample of B. cereus for antimicrobial sensitivity with bacitracin, optochin, nafcillin, novobiocin, cefoxitin, and oxacillin. Of all of those, only novobiocin was a successful antimicrobial and produced a zone of inhibition. We also tested four disinfectants, 70% isopropyl alcohol, 10% bleach, orange, and 100% lysol. Lysol was the only disinfectant that produced a zone of inhibition.

While B. cereus is associated mainly with food poisoning, it is being increasingly reported to be a cause of serious and potentially fatal non-gastrointestinal-tract infections.The pathogenicity of B. cereus, whether intestinal or nonintestinal, is intimately associated with the production of tissue-destructive exoenzymes. Among these secreted toxins are four hemolysins, three distinct phospholipases, an emesis-inducing toxin, and proteases. [1].

References

[1] Bottone, E. (2010). Bacillus cereus, a Volatile Human Pathogen. CMR, 382-398. doi:10.1128

Author

Page authored by Zaneta Wu and Desiree Weinstock, students of Prof. Kristine Hollingsworth at Austin Community College.