The location where I grabbed my soil sample was in Round Rock, Texas, on the edge of a residential area and a parking lot. It was September 02, 2015 around noon and the temperature was 90ºF with humidity of 45% and air pressure of 30 inches. There was no rainfall on that day or the past seven. I grabbed the surface soil which was very rocky and then an hour later I was able to do soil dilutions. The precise GPS location of my soil sample location was 30º29'56.9" N and 97º36'05.1" W.
Description and Significance
Describe the appearance (colonial and cellular), possible antimicrobial activity etc. of the organism, and why the organism might be significant.
When cultured on an LB agar, Arthrobacter oxydans is a milky white, opaque, round, convex and small, almost punctiform shape.
When it comes to Arthrobacter, it's a special cellular shape. Depending on what point you stain the bacteria, you can get either rods, or cocci. In the younger phase, when plated on to fresh media, Arthrobacter tends to be a rod shaped and upon aging tends to morph into it's cocci stage, in which was the stage we were able to observe it under a microscope. It was also gram-positive (but can appear gram-negative in younger stages) and our endospore stain showed that it was a non spore producing bacterium without a capsule.
Arthrobacter is also non-motile and completely susceptible to E. coli and S. aureus, with our plates being overgrown with each bacteria.
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.
The genome of Arthrobacter sp. Rue61a consists of a single circular chromosome of 4,736,495 bp. The genome of strain Rue61a contains numerous genes associated with osmoprotection, and a high number of genes coding for transporters. It encodes a broad spectrum of enzymes for the uptake and utilization of various sugars and organic nitrogen compounds. Rue61a reflects the saprophytic lifestyle and nutritional versatility of the organism and a strong adaptive potential to environmental stress.
Our 16S ribosomal sequence we obtained from PCR and sequencing is:
FORWARD: ATGCAGCGACGCCGCGTGAGGGATGACGGCCTTC GGGTTGTAAACCTCTTTCAGTAGGGAAGAAGCGAAAGTGACGGTACCTGCAGAAGAAGCGCCGGCTA ACTACGTGCCAGCAGCCGCGGTAATACGTAGGGCGCAAGCGTTATCCGGAATTATTGGGCGTAAAGA GCTCGTAGGCGGTTTGTCGCGTCTGCCGTGAAAGTCCGGGGCTCAACTCCGGATCTGCGGTGGGTA CGGGCAGACTAGAGTGATGTAGGGGAGACTGGAATTCCTGGTGTAGCGGTGAAATGCGCAGATATC AGGAGGAACACCGATGGCGAAGGCAGGTCTCTGGGCATTAACTGACGCTGAGGAGCGAAAGCATG GGGAGCGAACAGGATTAGATACCCTGGTAGTCCATGCCGTAAACGTTGGGCACTAGGTGTGGGGG ACATTCCACGTTTTCCGCGCCGTAGCTAACGCATTAAGTGCCCCGCCTGGGGAGTACGGCCGCAA GGCTAAAACTCAAAGGAATTGACGGGGGCCCGCACAAGCGGCGGAGCATGCGGATTAATTCGATG CAACGCGAAGAACCTTACCAAGGCTTGACATGAACCGGAAATACCTGGAGACAGGTGCCCCGCTT GCGGTCGGTTTACAGGTGGTGCATGGTTGTCGTCAGCTCGTGCCGTGAG
REVERSE: CCGACCGCAAGCGGGGCACCTGTCTCCAGGTATTTCCGGTTCATG TCAAGCCTTGGTAAGGTTCTTCGCGTTGCATCGAATTAATCCGCATGCTCCGCCGCTTGTGCGGGCCCCCGTCAATTCCT TTGAGTTTTAGCCTTGCGGCCGTACTCCCCAGGCGGGGCACTTAATGCGTTAGCTACGGCGCGGAAAACGTGGAATGTCC CCCACACCTAGTGCCCAACGTTTACGGCATGGACTACCAGGGTATCTAATCCTGTTCGCTCCCCATGCTTTCGCTCCTCA GCGTCAGTTAATGCCCAGAGACCTGCCTTCGCCATCGGTGTTCCTCCTGATATCTGCGCATTTCACCGCTACACCAGGAA TTCCAGTCTCCCCTACATCACTCTAGTCTGCCCGTACCCACCGCAGATCCGGAGTTGAGCCCCGGACTTTCACGGCAGAC GCGACAAACCGCCTACGAGCTCTTTACGCCCAATAATTCCGGATAACGCTTGCGCCCTACGTATTACCGCGGCTGCTGGC ACGTAGTTAGCCGGCGCTTCTTCTGCAGGTACCGTCACTTTCGCTTCTTCCCTACTGAAAGAGGTTTACAACCCGAAGGC CGTCATCCCTCACGCGGCGTCGCTGCATCAGGCTTGCGCCCATTGTGCAATATTCCCCACTGCTGCCTCCCGTAGGAGTA CTG
Cell Structure, Metabolism and Life Cycle
Interesting features of cell structure; how it gains energy; what important molecules it produces.
The genus Arthrobacterincludes catalase-positive coryneform bacteria with an oxidative metabolism, the cell wall of which contains L-lysine as the diamino acid and cellular fatty acids of the branched type.
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.
BIOCHEMICAL TEST RESULTS
- Phenol Red Broth Tests: Glucose: negative; Lactose: negative; Sucrose: positive
- Starch Hydrolysis Test: positive
- Casein Hydrolysis Test: positive
- Gelatin Hydrolysis Test: negative
- DNA Hydrolysis Test: negative
- Lipid Hydrolysis Test: positive
- Methyl Red Test: negative
- Voges Proskauer Test: negative
- Citrate Test: negative
- SIM Tests: negative for all three
- Nitrate Reduction: negative
- Urea Hydrolysis: negative
- Triple Sugar Iron Agar: negative
- Oxidase Test: negative
- Eosin Methylene Blue Agar (EMB) Test: negative
- Hektoen Enteric Agar (HE) Test: negative
- MacConkey Agar Test: negative
- Decarboxylation Tests: Arginine: negative; Lysine: negative; Orinithine: negative
- Phenylalanine Deaminase Test: negative
- Catalase Test: positive
- Blood Agar Test: negative
- Mannitol Salt Agar (MSA) Test: negative
- Phenylethyl Alcohol Agar (PEA) Test: negative
- Antimicrobial Sensitivity (Kirby-Bauer Method) Test: Vancomyocin: susceptible; Sufisoxazole: susceptible; Linezolid: susceptible Bacitracin: susceptible; Oxacillin: resistant; Cefoxifin: susceptible
- Disinfectant Sensitivity Test: Cinnamon: susceptible; Tea Tree Oil: susceptible; 70% Isopropyl Alcohol: susceptible 10% Lysol: susceptible; 10% Bleach: resistant; Orange Oil: susceptible
The pathological significance has yet to be assessed. Several studies have shown that this bacteria has been isolated from superficial body sites and blood after surgery but their role in disease is still unknown. They were not considered to be environmental contaminants since, except in blood cultures, numerous colonies were present at primary isolation. This bacteria is susceptible to many antibiotics.
[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.
Niewerth et al.: Complete genome sequence and metabolic potential of the quinaldine-degrading bacterium Arthrobacter sp. Rue61a. BMC Genomics 2012 13:534.
Funke G., von Graevenitz A., Clarridge III J. E., Bernard K. A. (1997) Clinical microbiology of coryneform bacteria. Clin. Microbiol. Rev. 10:125–159.
Page authored by Nadia Didehbani and Kendra Dubec, students of Prof. Kristine Hollingsworth at Austin Community College.