Microbial ecology
Microbial ecology (or environmental microbiology) is the ecology of microorganisms: their relationship with one another and with their environment. It concerns the three major domains of life—Eukaryota, Archaea, and Bacteria—as well as viruses.[2]
Microorganisms, by their omnipresence, impact the entire
History
While microbes have been studied since the seventeenth century, this research was from a primarily physiological perspective rather than an ecological one.
Beijerinck and Windogradsky, however, were focused on the physiology of microorganisms, not the microbial
Progress in microbial ecology has been tied to the development of new technologies. The measurement of biogeochemical process rates in nature was driven by the availability of radioisotopes beginning in the 1950s. For example, 14CO2 allowed analysis of rates of photosynthesis in the ocean (ref). Another significant breakthrough came in the 1980s, when microelectrodes sensitive to chemical species like O2 were developed.[15] These electrodes have a spatial resolution of 50–100 μm, and have allowed analysis of spatial and temporal biogeochemical dynamics in microbial mats and sediments.[citation needed]
Although measuring biogeochemical process rates could analyse what processes were occurring, they were incomplete because they provided no information on which specific microbes were responsible. It was long known that 'classical' cultivation techniques recovered fewer than 1% of the microbes from a natural habitat. However, beginning in the 1990s, a set of cultivation-independent techniques have evolved to determine the relative abundance of microbes in a habitat. Carl Woese first demonstrated that the sequence of the 16S ribosomal RNA molecule could be used to analyse phylogenetic relationships.[16] Norm Pace took this seminal idea and applied it to analysfe 'who's there' in natural environments. The procedure involves (a) isolation of nucleic acids directly from a natural environment, (b) PCR amplification of small subunit rRNA gene sequences, (c) sequencing the amplicons, and (d) comparison of those sequences to a database of sequences from pure cultures and environmental DNA.[17] This has provided tremendous insights into the diversity present within microbial habitats. However, it does not resolve how to link specific microbes to their biogeochemical role. Metagenomics, the sequencing of total DNA recovered from an environment, can provide insights into biogeochemical potential,[18] whereas metatranscriptomics and metaproteomics can measure actual expression of genetic potential but remains more technically difficult.[19]
Roles
Microorganisms are the backbone of all
Other microbes are
Due to the high level of horizontal gene transfer among microbial communities,[24] microbial ecology is also of importance to studies of evolution.[25]
Evolution
Microbial ecology contributes to the evolution in many different parts of the world. For example, different microbial species evolved CRISPR dynamics and functions, allowing a better understanding of human health.[26]
Symbiosis
Microbes, especially bacteria, often engage in symbiotic relationships (either positive or negative) with other microorganisms or larger organisms. Although physically small, symbiotic relationships amongst microbes are significant in eukaryotic processes and their evolution.[27][28] The types of symbiotic relationship that microbes participate in include mutualism, commensalism, parasitism,[29] and amensalism[30] which affect the ecosystem in many ways.
Mutualism
Mutualism in microbial ecology is a relationship between microbial species and humans that allows for both sides to benefit.
Commensalism
Commensalism is very common in microbial world, literally meaning "eating from the same table".[38] Metabolic products of one microbial population are used by another microbial population without either gain or harm for the first population. There are many "pairs "of microbial species that perform either oxidation or reduction reaction to the same chemical equation. For example, methanogens produce methane by reducing CO2 to CH4, while methanotrophs oxidise methane back to CO2.[39]
Amensalism
Microbial resource management
In built environment and human interaction
Microbes exist in all areas, including homes, offices, commercial centers, and hospitals. In 2016, the journal Microbiome published a collection of various works studying the microbial ecology of the built environment.[44]
A 2006 study of pathogenic bacteria in hospitals found that their ability to survive varied by the type, with some surviving for only a few days while others survived for months.[45]
The lifespan of microbes in the home varies similarly. Generally bacteria and viruses require a wet environment with a humidity of over 10 percent.[46] E. coli can survive for a few hours to a day.[46] Bacteria which form spores can survive longer, with Staphylococcus aureus surviving potentially for weeks or, in the case of Bacillus anthracis, years.[46]
In the home, pets can be carriers of bacteria; for example, reptiles are commonly carriers of salmonella.[47]
S. aureus is particularly common, and asymptomatically colonizes about 30% of the human population;[48] attempts to decolonize carriers have met with limited success[49] and generally involve mupirocin nasally and chlorhexidine washing, potentially along with vancomycin and cotrimoxazole to address intestinal and urinary tract infections.[50]
Antimicrobials
Some metals, particularly copper, silver, and gold have antimicrobial properties. Using antimicrobial copper-alloy touch surfaces is a technique which has begun to be used in the 21st century to prevent transmission of bacteria.[51][52] Silver nanoparticles have also begun to be incorporated into building surfaces and fabrics, although concerns have been raised about the potential side-effects of the tiny particles on human health.[53] Due to the antimicrobial properties certain metals possess, products such as medical devices are made using those metals.[52]
See also
- Microbial biogeography
- Microbial loop
- Outline of ecology
- International Society for Microbial Ecology
- The ISME Journal
References
- PMID 11864374.
- ISBN 978-1-118-01582-7. Retrieved May 25, 2013.
- ^
Bowler, Chris; Karl, David M.; Colwell, Rita R. (2009). "Microbial oceanography in a sea of opportunity". Nature. 459 (7244): 180–4. S2CID 4426467.
- PMID 19657372.
- PMID 8324114.
- PMID 9618454.
- ^ "number of stars in the observable universe - Wolfram|Alpha". Retrieved November 22, 2011.
- ISBN 978-0-203-49145-4. Retrieved May 25, 2013.
- ^
Delong, Edward F. (2009). "The microbial ocean from genomes to biomes" (PDF). Nature. 459 (7244): 200–6. S2CID 205216984.
- ^
Lupp, Claudia (2009). "Microbial oceanography". Nature. 459 (7244): 179. PMID 19444202.
- ^ ISBN 978-0-12-373944-5.
- S2CID 22211340.
- ^
De Wit, Rutger; Bouvier, Thierry (2006). "'Everything is everywhere, but, the environment selects'; what did Baas Becking and Beijerinck really say?". Environmental Microbiology. 8 (4): 755–8. PMID 16584487.
- ISBN 978-0-321-64963-8.
- ISBN 978-1-4757-0613-0, retrieved September 21, 2020
- PMID 270744.
- PMID 28928718.
- S2CID 220282070.
- PMID 31608125.
- ISBN 978-0-12-415974-7. Retrieved May 25, 2013.
- S2CID 256786335.
- S2CID 201233849.
- PMID 33671192.
- ^
McDaniel, L. D.; Young, E.; Delaney, J.; Ruhnau, F.; Ritchie, K. B.; Paul, J. H. (2010). "High Frequency of Horizontal Gene Transfer in the Oceans". Science. 330 (6000): 50. S2CID 45402114.
- ^
Smets, Barth F.; Barkay, Tamar (2005). "Horizontal gene transfer: Perspectives at a crossroads of scientific disciplines". Nature Reviews Microbiology. 3 (9): 675–8. S2CID 2265315.
- S2CID 85501449.
- ^ OCLC 777261246.
- PMID 28254477.
- OCLC 317664342.
- ^ S2CID 22872711.
- ^ OCLC 53231924.
- S2CID 10348127.
- ^ PMID 28254477.
- PMID 27872277.
- ISBN 978-3-642-30122-3
- S2CID 205009562.
- S2CID 4413069.
- S2CID 88750087
- ISBN 978-0-12-026147-5
- S2CID 23694837.
- OCLC 317664342.
- ^
Verstraete, Willy (2007). "Microbial ecology and environmental biotechnology". The ISME Journal. 1 (1): 4–8. PMID 18043608.
- ^
Ott, J. (2005). Marine Microbial Thiotrophic Ectosymbioses. Oceanography and Marine Biology: An Annual Review. Vol. 42. pp. 95–118. ISBN 978-0-203-50781-0.
- ^ "Microbiology of the Built Environment". www.biomedcentral.com. Retrieved September 18, 2016.
- PMID 16914034.
- ^ a b c "How long do microbes like bacteria and viruses live on surfaces in the home at normal room temperatures?". August 23, 2002. Retrieved September 18, 2016.
- ^ "Raw Diets Linked To Salmonella". June 9, 2009. Retrieved September 18, 2016.
- PMID 26016486.
- ^ "Many factors involved in decolonization of S. aureus". www.healio.com. Retrieved September 18, 2016.
- S2CID 34294193.
- ^ "The bacteria-fighting super element making a return to hospitals: Copper". Washington Post. Retrieved September 18, 2016.
- ^ PMID 33961541.
- ^ "Silver nanoparticles kill germs, raise health concerns". Retrieved September 18, 2016.