Bacillus thermoamylovorans

From MicrobeWiki, the student-edited microbiology resource

Introduction

Do you know what could be in your milk? Food pasteurization and sterilization techniques are an important aspect of the food industry as it helps to keep us safe from potentially pathogenic microbes that would make us sick otherwise. The potential benefits have not yet been discovered (1). Typically found in a warmer environment such as hot- water springs with pH between 5.4-8.5, Bacillus thermoamylovorans, undergo facultative anaerobic fermentation. Facultative anaerobic fermentation allows Bacillus thermoamylovorans to grow either in the presence of oxygen or without, thus they can metabolize organic substrates such as carbohydrates (glucose and lactose) (2). With the potential to harm humans as a thermotolerant microbe, Bacillus thermoamylovorans can endure pasteurization and other food sterilization processes that are meant to kill off microbes due to its spores, creating issues for the food industry. In pasteurization, Bacillus thermoamylovorans can live between 40 ̊C and 58 ̊C, with the possibility of survival at 37 ̊C and no survival at 30 ̊C (1). Pictured below is a phase-contrast photomicrograph image of B. thermoamylovorans at 1000x magnification, showing that this organism is rod shaped and Gram-positive (2).

Classification

Higher Order Taxa Bacterial; Firmicutes; Bacilli; Bacillales; Bacillaceae Species Bacillus thermoamylovorans, type strain LMG 18084T

NCBI: Taxonomy JGI:GOLD

Phylogenetic Relatedness

Bacillus thermoamylovorans is a member of the Genus Bacillus, meaning it is comprised of a component that allows for the bacteria’s survival in many extreme conditions (5). 16S rRNA almost complete gene sequences were used to comprise the phylogenetic tree, also using maximum likelihood methods. Cultures were grown on Bacillus fumarioli agar (BFA) and TSA over several days are other methods used for compiling this phylogenetic tree. The closest relative of Bacillus thermoamylovorans according to the phylogenetic tree below is Bacillus thermolactis. Based on the 16S rRNA gene sequence analysis, Bacillus thermoamylovorans are 93.9% genetically similar to the species Bacillus thermolactis (1).

Ecological Habitat

B. thermoamylovorans was originally isolated from a hot spring in South Sumatera, Indonesia (11), and since then have been found in dairy farm processing equipment, and animal and human guts (6). Although there is not much information on B. thermoamylovorans hot-spring habitat, it is known that most hot-springs have a temperature well above 50 ˚C. This microbe can be unfavorable to humans as they form heat resistant spores which cause the spoilage of certain dairy farm foods. The foods become inedible, due to the bacteria’s spore-forming which allows it to withstand extreme temperature environments and grow vegetatively after treatment (1). This microbe poses a huge threat to the food processing industry, effecting many products that individuals require to be in the stores, such as cheeses, milk, and any other dairy products. Not only can the bacterium be found in hot-springs where both humans and thermophilic mirobes coexist in, and dairy farms, it can also be found in sewage sludge, degrading organic material. Bacillus thermoamylovorans form creamy white colored colonies. Bacillus thermoamylovorans can live in the presence of oxygen or without oxygen, in about 37-58 ̊C environments (6). B. thermoamylovorans optimally grow at pH 7.0 but can grow within a pH range of 5.4-8.5 (2).

Significance to the Environment

LO: “Microbes are essential for life as we know it and the processes that support life” – how does your organism and your organisms’ metabolism support life on planet Earth?

LO: Human impact on the environment influences the evolution of microorganisms (e.g., emerging diseases and the selection of antibiotic resistance).

  • Describe how this microbe cycles nutrients in the environment. Note that an organism’s environment might be in or on another organism (e.g. bacteria in insect digestive system)
  • Include links to other MicrobeWiki pages on nutrient cycling or other reputable information on nutrient cycling geared toward the public (podcasts, blogs, gov or professional sites)
  • Are there human-induced changes to the environment that have influenced this microbe’s evolution, population numbers, or spread? (e.g. agriculture, clear-cutting/destruction of natural areas, greenhouse gasses, high nitrogen/phosphorous run-off, oil spills, overuse of antibiotics,...)

Ecological Lifestyle and Interactions

LO: “Microorganisms provide essential models that give us fundamental knowledge about life processes.”

LO: “Microorganisms are ubiquitious and live in diverse and dynamic ecosystems."

LO: “Microorganisms and their environment interact with and modify each other.”

LO: “Most bacterial in nature live in biofilm communities.”

  • Describe the organism’s lifestyle, the organisms it interacts with, and how these interactions influence their environment.
  • Name and describe the kind of lifestyle of the organism (free-living? host-associated? obligate? Facultative? Parasitic? Mutualistic? Saprophytic?)
    • If the organism is mutualistic or pathogenic, state what host it most commonly associates with
    • If parasitic – what disease does it cause and what are the symptoms?
    • If mutualistic – what cost/benefit does it receive from the host and what cost/benefit does it give the host?
    • If saprophytic, what kinds of organisms does it feed upon?
    • Does the lifestyle of the organism changes with the host or context? If so, you might select one type of lifestyle to focus on, but then mention the other associations in a few sentences.
  • Describe key groups of microbes that your microbe interacts or are associated with important processes found in this environment.
    • Link to other MicrobeWiki pages or other reputable resources where possible.
  • Describe biological interactions that might take place in this environment, using as many sections/subsections as you require.
    • Are there important biological interactions that are important in this environment?
    • Do these interactions influence microbial populations and their activities?
    • How do these interactions influence other organisms?

Significance to Humans

LO: “Microorganisms can interact with both human and nonhuman hosts in beneficial, neutral, and detrimental ways.”

LO: “Humans utilize (note: this is the correct way to use utilize!) and harness microorganisms and their products.”

  • Describe how this microbe has influenced human society now or in the past.
    • If your microbe is a pathogen, does the ecology and metabolism of the pathogen suggest how we can interrupt its interactions with the host?
  • If there is technology or product that this microbe is part of or could be a part of:
    • describe the technology
    • how this technology or product influences human lives.

Cell Structure

LO: Microbes have unique cell structures that can be targets for antibiotic, immunity, and phage infection.

LO: Microbes have specialized structures (e.g. flagella, endospores, and pili) that often confer critical capabilities.

Provide a physical and metabolic description of the organism. Are there special diagnostic media or methods to distinguish this microbe from close relatives?

  • Colony morphology (size, shape, texture, pigmentation, smell?, etc…)
  • Cell morphology
  • Gram type, if applicable
  • Motility
  • Any other important structures

Cell Metabolism

LO: “Microbes are essential for life as we know it and the processes that support life.” LO: “Microorganisms provide essential models that give us fundamental knowledge about life processes.” LO: Because the true diversity of microbial life is largely unknown, its effects and potential benefits have not been fully explored.

Provide a physical and metabolic description of the organism. Are there special diagnostic media or methods to distinguish this microbe from close relatives?

  • Optimal abiotic growth conditions (temperature, salinity, oxygen, UV)
  • Carbon growth sources
  • Other metabolic abilities
  • Any other unique abilities (e.g toxin production, antibiotic resistance, etc...)

.

Genome Structure, Content, and/or Gene Expression

LO: Genome structure and content provide insight into a microbe's evolutionary history, ecological niche, and interactions with hosts and other microbes.

LO: Mutations and horizontal gene transfer, with an immense variety of microenvironments, have selected for a huge diversity of microorganisms.

LO: The regulation of gene expression is influenced by external and internal molecular cues and/or signals.

LO: Cell genomes can be manipulated to alter cell function.

LO: Genetic variations can impact microbial functions (e.g. in biofilm formation, pathogenicity, and drug resistance).

Metrics

  • Genome size
  • % GC
  • number of chromosomes and/or plasmids?
  • Circular or linear?
  • Other interesting features?

Relevance

  • Why was this organism sequenced?
  • Where was this organism sequenced?
  • Provide a direct link to the sequenced genome
  • What does the genome tell us about this organism? Ie. What new insights do we have after it is sequenced?
  • Give an example of an interesting feature found in the genome (LGT, mutations, plasmids, antibiotic resistance, toxins, etc...).
  • Explain why this feature is important for the microbes’ survival or success.

Interesting Feature

LO: Mutations and horizontal gene transfer, with an immense variety of microenvironments, have selected for a huge diversity of microorganisms.

LO: Human impact on the environment influences the evolution of microorganisms (e.g., emerging diseases and the selection of antibiotic resistance).

LO: Because the true diversity of microbial life is largely unknown, its effects and potential benefits have not been fully explored.

Describe in detail one particularly interesting aspect of your organism.

  • Why is this detail interesting?
  • How does it help the organism survive?
  • How does this interesting feature influence the larger environment or other microbes?
  • How can this interesting feature be helpful to humans?
  • In ~3 sentences propose WHY more research and WHAT kind of new research should be done on this organism and others like it. Connect this to the learning objective about the importance of microbial diversity
  • If you have created a graphical abstract, meme, image, etc... about this organism and its interesting feature, include it here. You can put a creative commons copywrite it to control how other people use it: https://creativecommons.org/about/cclicenses/

References

1.Coorevits, A., Logan, N.A., Dinsdale, A.E., Halket, G., Scheldeman, P., Heyndrickx, M., Schumann, P., Van Landoschoot, A., and De Vos, P. “Bacillus thermolactis sp. nov., isolated from dairy farms, and emended description of Bacillus thermoamylovorans”. International Journal of Systemic and Evolutionary Microbiology. 2011. Volume 61. p. 1954-1961. https://doi.org/10.1099/ijs.0.024240-0

2.Combet Blanc, Y., Ollivier, B., Streicher, C., Patel, B.K.C., Dwivedi, P.P., Pot, B., Prensier G., and Garcia, J.L. “Bacillus thermoamylovorans sp. nov., a moderately thermophilic and amylolytic bacterium”. International Journal of Systematic Bacteriology. 1995. Volume 45. p. 9-16.

3.Lu, C., Sheng-Wei, Z., Yu-Jun, Shen., Guo-Di, Z., Hong-Tao, L., and Zhi-Ying, W. “ Complete genome sequence provides insight into the biodrying-related microbial function of Bacillus thermoamylovorans isolated from sewage sludge biodrying material”. Bioresource Technology. 2018. Volume 260. p. 141-149. https://doi.org/10.1016/j.biortech.2018.03.121

4.Cultivation-independent approaches by Jeremy Dodsworth. Hedlund, BP., et al. “Impact of single-cell genomics and metagenomics on the emerging view of extremophile “microbial dark matter”. Extremophiles. 2014. Volume 18. p. 865-875. https://jgi.doe.gov/elucidating-extremophilic-microbial-dark-matter/

5.Logan, N.A., and De Vos, P. “Bacillus”. Bergey’s Manual of Systematics of Archaea and Bacteria. 2015. p. 1-164.

6.Berendsen, E.M., Krawczyk, A.O., Klaus, K., Jong, A., Boekhorst, J., et al. “Bacillus thermoamylovorans spores with very-high-level heat resistance germinate poorly in rich medium despite the presence of ger clusters but efficiently upon exposure to calcium-dipicolinic acid”. Applied and Environmental Microbiology. 2015. Volume 81. p. 7791-7801. doi: https://dx.doi.org/10.1138%2FAEM.01993-15

7.Flint, S., Gonzaga, Z., Good, J., and Palmer, J. “Bacillus thermoamylovorans- a new threat to the dairy industry – a review”. International dairy Journal. 2017. Volume 65. p. 38-43. https://doi.org/10.1016/j.idairyj.2016.10.002

8.Muehlhoff E, Bennett A, McMahon D, editors. Milk and dairy products in human nutrition. Rome, Italy: FAO; 2013.

9.Miyamoto, H., Seta, M., Horiuchi, S., Iwasawa, I., Naito, T., et al. “Potential probiotic thermophiles isolated from mice after compost ingestion”. Journal of Applied Microbiology. 2012. Volume 114. p. 1147-1157. doi: 10.1111/jam.12131

10.Amy Quinton. Raw milk may do more harm than good [internet]. UC Davis; 2020. Available from: https://www.ucdavis.edu/news/raw-milk-may-do-more-harm-good/

11.Yohandini, H., J., H. “Isolation and Phylogenetic analysis of thermophile community within Tanjung Sakti hot spring, South Sumatera, Indonesia”. HAYATI Journal of Biosciences. 2015. Volume 22. p. 143-148. http://dx.doi.org/10.1016/j.hjb.2015.10.006

12.Fusco, V., Chieffi, D., Fanelli, F., Logrieco, A., Cho, G.S., et al. “Microbial quality and safety of milk and milk products in the 21st century”. Comprehensive Revies in Food Science and Food Safety. 2020. Volume 19. p. 2013-2049. doi:10.1111/1541-4337.12568

13.Klebsiella [Internet]. microbewiki. [cited 2020Dec12]. Available from: https://microbewiki.kenyon.edu/index.php/Klebsiella

14.Pseudomonas [Internet]. microbewiki. [cited 2020Dec12]. Available from: https://microbewiki.kenyon.edu/index.php/Pseudomonas

15.Staphylococcus aureus [Internet]. microbewiki. [cited 2020Dec12]. Available from: https://microbewiki.kenyon.edu/index.php/Staphylococcus_aureus

16.Staphylococcus [Internet]. microbewiki. [cited 2020Dec12]. Available from: https://microbewiki.kenyon.edu/index.php/Staphylococcus

17.Streptococcus [Internet]. microbewiki. [cited 2020Dec12]. Available from: https://microbewiki.kenyon.edu/index.php/Streptococcus



Edited by <Teresa Watkins>, a @MicrobialTowson student of Dr. Anne M. Estes at Towson University. Template adapted from templates by Angela Kent, University of Illinois at Urbana-Champaign and James W. Brown, Microbiology, NC State University.