Table of ContentsView AllTable of ContentsBehaviorDefinitionBiologyRisks
Table of ContentsView All
View All
Table of Contents
Behavior
Definition
Biology
Risks
Bacteriaare single-celled prokaryote organisms, which means they comprise one single biological cell with no nucleus. They exist in pairs, chains, or clusters. They are found everywhere, including on and in the human body and within water, soil, and food, and can play a significant role in various ecosystems.
There are roughly 30,000 different species of bacteria. Some can harm human health, while others can be helpful. Those that are helpful maintain overall health in the body. The most well-known “good” bacteria isfound within the gut.
Bacteria are classified into different groups depending on their shape. There are five distinct bacterial shapes: spherical, rod, spiral, comma, and corkscrew.
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Bacteria, just like any other living organism, will do what it takes to ensure their survival. This means they will seek the best environments and food sources to thrive.
Some species of bacteria help to maintain overall health, while others are harmful and can cause illness.
Helpful Bacteria
There are many helpful strains of bacteria. Some help in human health, while others help to ensure the overall function of various ecosystems. Examples of good bacteria are:
Harmful Bacteria
Harmful bacteria cause damage to human health or the ecosystem. They are referred to as pathogenic because they cause disease or illness.
Some examples of pathogenic bacteria include:
How Do Harmful Bacteria Cause Damage?When harmful bacteria enter the body, they release toxins, damaging cells and tissues, leading to illness or disease. They can cause various bodily systems to be harmed, including the gut, the lungs, the skin, and the genital area.
How Do Harmful Bacteria Cause Damage?
When harmful bacteria enter the body, they release toxins, damaging cells and tissues, leading to illness or disease. They can cause various bodily systems to be harmed, including the gut, the lungs, the skin, and the genital area.
What Does “Bacterial” Mean?
These infections can spread through the air, contaminated food or water, insect bites, and sexual activity. People either recover from a bacterial infection without treatment or they may requireantibiotic treatment.Antibiotics often are necessary if the infection worsens or lingers. The type of antibiotic used depends on the bacterium causing the infection.
The Risk of Antibiotic ResistanceSome bacteria become antibiotic resistant, meaning the drugs designed to kill them are less effective or do not work at all against them. Various factors can encourage antibiotic resistance, including:Overprescribing or misuse of antibiotics when they’re not neededInsufficient regulation of specific antibioticsPoor patient adherence when given antibiotics
The Risk of Antibiotic Resistance
Some bacteria become antibiotic resistant, meaning the drugs designed to kill them are less effective or do not work at all against them. Various factors can encourage antibiotic resistance, including:Overprescribing or misuse of antibiotics when they’re not neededInsufficient regulation of specific antibioticsPoor patient adherence when given antibiotics
Some bacteria become antibiotic resistant, meaning the drugs designed to kill them are less effective or do not work at all against them. Various factors can encourage antibiotic resistance, including:
Antibiotic Resistance: How It Happens and How You Can Prevent It
Basic Bacteria Biology
Bacteria is split up into five different classifications, including:
These shape classifications help identify the different bacteria. There are various structures within a bacterial cell, all of which play a role in the cell’s survival. They include:
Bacteria can feed and get what they need to survive in a few different ways. Heterotrophic bacteria break down animal waste, dead organisms, or plant litter to survive and obtain the nutrient they need: simple glucose. These bacteria thrive in food, soil, or water.
Autotrophic bacteria create their own food through photosynthesis or chemosynthesis. These processes use sunlight, water, and carbon dioxide or carbon dioxide, water, and chemicals to obtain energy and food. They prefer water habitats, such as lakes, rivers, or oceans. They can also survive in soil.
When bacteria have glucose to use as energy, they can reproduce during a process known as binary fission. Binary fission occurs when one single-celled organism, in this case a bacterium, divides into two identical cells known as daughter cells. Essentially, bacteria replicate themselves repeatedly to thrive. In some cases, this division process can occur in as little as 20 minutes, allowing the bacteria to replicate into significantly high numbers quickly.
Viral vs. Bacterial Infection: What’s the Difference?
How to Support Bacteria in the Gut
Thegut is hometo both good and bad bacteria that, when in balance, help maintain overall gut health and the health of the human body. The good bacteria help to keep the harmful bacteria from getting out of control. While this process continuously occurs on a cellular level, there are things you can do to aid in the balance of good and bad bacteria within the gut.
Types of fiber that help to encourage a healthy balance of gut bacteria include:
Risks of Bacteria and Long-Term Impact
Harmful bacteria can set up shop in the body, damage cells and tissues, and lead to severe adverse health complications, the worst of which is death. In mild cases of bacterial invasion, people can experience various illnesses.
If a bacterial infection is persistent, it can increase the chances of death and severe illness that requires more intensive care. These types of long-term infections can also be especially difficult to eradicate, putting the host at a high risk of severe health consequences.
Signs of a Bacterial or Viral Infection
Summary
There are over 30,000 different species of the single-celled organisms known as bacteria, some of which are actually helpful to human health and the global ecosystem.
17 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Microbiology Society.What are bacteria.Duranti S, Longhi G, Ventura M, et al.Exploring the ecology of bifidobacteria and their genetic adaptation to the mammalian gut.Microorganisms. 2020;9(1):8. Published 2020 Dec 22. doi:10.3390/microorganisms9010008Backer R, Rokem JS, Ilangumaran G, et al.Plant growth-promoting rhizobacteria: Context, mechanisms of action, and roadmap to commercialization of biostimulants for sustainable agriculture.Front Plant Sci. 2018;9:402666.Pan M, Hidalgo-Cantabrana C, Goh YJ, Sanozky-Dawes R, Barrangou R.Comparative analysis ofLactobacillus gasseriandLactobacillus crispatusisolated from human urogenital and gastrointestinal tracts.Front Microbiol. 2020;10:3146. doi:10.3389/fmicb.2019.03146Microbiology society.Streptomyces.National Library of Medicine.Pseudomonas.Talwar A, Tsang CA, Price SF, et al.Tuberculosis — United States, 2018.MMWR Morb Mortal Wkly Rep. 2019;68:257–262. doi:10.15585/mmwr.mm6811a2Nemser SM, Doran T, Grabenstein M, et al.Investigation of listeria, salmonella, and toxigenic escherichia coli in various pet foods.Foodborne Pathog Dis. 2014;11(9):706-709. doi:10.1089/fpd.2014.1748Martin JM.The mysteries of streptococcal pharyngitis.Curr Treat Options Pediatr. 2015;1(2):180-189. doi:10.1007/s40746-015-0013-9King JM, Kulhankova K, Stach CS, Vu BG, Salgado-pabón W.Phenotypes and virulence among staphylococcus aureus. USA100, USA200, USA300, USA400, and USA600 Clonal Lineages. mSphere. 2016;1(3). doi:10.1128/CMR.00134-14MedlinePlus.Immune response.Onakpoya IJ, Walker AS, Tan PS, Spencer EA, Gbinigie OA, Cook J, Llewelyn MJ, Butler CC.Overview of systematic reviews assessing the evidence for shorter versus longer duration antibiotic treatment for bacterial infections in secondary care.PLoS One.2018 Mar 28;13(3):e0194858. doi:10.1371/journal.pone.0194858Chen Q, Li D, Beiersmann C, Neuhann F, Moazen B, Lu G, Müller O.Risk factors for antibiotic resistance development in healthcare settings in China: a systematic review.Epidemiol Infect.2021 Jun 3;149:e141. doi:10.1017/S0950268821001254Medical Microbiology.Chapter 2 - structure.Flexbooks.org.Bacteria nutrition.Harvard T.H. Chan School of Public Health.The microbiome.Grant SS, Hung DT.Persistent bacterial infections, antibiotic tolerance, and the oxidative stress response.Virulence.2013 May 15;4(4):273-83. doi:10.4161/viru.23987
17 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Microbiology Society.What are bacteria.Duranti S, Longhi G, Ventura M, et al.Exploring the ecology of bifidobacteria and their genetic adaptation to the mammalian gut.Microorganisms. 2020;9(1):8. Published 2020 Dec 22. doi:10.3390/microorganisms9010008Backer R, Rokem JS, Ilangumaran G, et al.Plant growth-promoting rhizobacteria: Context, mechanisms of action, and roadmap to commercialization of biostimulants for sustainable agriculture.Front Plant Sci. 2018;9:402666.Pan M, Hidalgo-Cantabrana C, Goh YJ, Sanozky-Dawes R, Barrangou R.Comparative analysis ofLactobacillus gasseriandLactobacillus crispatusisolated from human urogenital and gastrointestinal tracts.Front Microbiol. 2020;10:3146. doi:10.3389/fmicb.2019.03146Microbiology society.Streptomyces.National Library of Medicine.Pseudomonas.Talwar A, Tsang CA, Price SF, et al.Tuberculosis — United States, 2018.MMWR Morb Mortal Wkly Rep. 2019;68:257–262. doi:10.15585/mmwr.mm6811a2Nemser SM, Doran T, Grabenstein M, et al.Investigation of listeria, salmonella, and toxigenic escherichia coli in various pet foods.Foodborne Pathog Dis. 2014;11(9):706-709. doi:10.1089/fpd.2014.1748Martin JM.The mysteries of streptococcal pharyngitis.Curr Treat Options Pediatr. 2015;1(2):180-189. doi:10.1007/s40746-015-0013-9King JM, Kulhankova K, Stach CS, Vu BG, Salgado-pabón W.Phenotypes and virulence among staphylococcus aureus. USA100, USA200, USA300, USA400, and USA600 Clonal Lineages. mSphere. 2016;1(3). doi:10.1128/CMR.00134-14MedlinePlus.Immune response.Onakpoya IJ, Walker AS, Tan PS, Spencer EA, Gbinigie OA, Cook J, Llewelyn MJ, Butler CC.Overview of systematic reviews assessing the evidence for shorter versus longer duration antibiotic treatment for bacterial infections in secondary care.PLoS One.2018 Mar 28;13(3):e0194858. doi:10.1371/journal.pone.0194858Chen Q, Li D, Beiersmann C, Neuhann F, Moazen B, Lu G, Müller O.Risk factors for antibiotic resistance development in healthcare settings in China: a systematic review.Epidemiol Infect.2021 Jun 3;149:e141. doi:10.1017/S0950268821001254Medical Microbiology.Chapter 2 - structure.Flexbooks.org.Bacteria nutrition.Harvard T.H. Chan School of Public Health.The microbiome.Grant SS, Hung DT.Persistent bacterial infections, antibiotic tolerance, and the oxidative stress response.Virulence.2013 May 15;4(4):273-83. doi:10.4161/viru.23987
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Microbiology Society.What are bacteria.Duranti S, Longhi G, Ventura M, et al.Exploring the ecology of bifidobacteria and their genetic adaptation to the mammalian gut.Microorganisms. 2020;9(1):8. Published 2020 Dec 22. doi:10.3390/microorganisms9010008Backer R, Rokem JS, Ilangumaran G, et al.Plant growth-promoting rhizobacteria: Context, mechanisms of action, and roadmap to commercialization of biostimulants for sustainable agriculture.Front Plant Sci. 2018;9:402666.Pan M, Hidalgo-Cantabrana C, Goh YJ, Sanozky-Dawes R, Barrangou R.Comparative analysis ofLactobacillus gasseriandLactobacillus crispatusisolated from human urogenital and gastrointestinal tracts.Front Microbiol. 2020;10:3146. doi:10.3389/fmicb.2019.03146Microbiology society.Streptomyces.National Library of Medicine.Pseudomonas.Talwar A, Tsang CA, Price SF, et al.Tuberculosis — United States, 2018.MMWR Morb Mortal Wkly Rep. 2019;68:257–262. doi:10.15585/mmwr.mm6811a2Nemser SM, Doran T, Grabenstein M, et al.Investigation of listeria, salmonella, and toxigenic escherichia coli in various pet foods.Foodborne Pathog Dis. 2014;11(9):706-709. doi:10.1089/fpd.2014.1748Martin JM.The mysteries of streptococcal pharyngitis.Curr Treat Options Pediatr. 2015;1(2):180-189. doi:10.1007/s40746-015-0013-9King JM, Kulhankova K, Stach CS, Vu BG, Salgado-pabón W.Phenotypes and virulence among staphylococcus aureus. USA100, USA200, USA300, USA400, and USA600 Clonal Lineages. mSphere. 2016;1(3). doi:10.1128/CMR.00134-14MedlinePlus.Immune response.Onakpoya IJ, Walker AS, Tan PS, Spencer EA, Gbinigie OA, Cook J, Llewelyn MJ, Butler CC.Overview of systematic reviews assessing the evidence for shorter versus longer duration antibiotic treatment for bacterial infections in secondary care.PLoS One.2018 Mar 28;13(3):e0194858. doi:10.1371/journal.pone.0194858Chen Q, Li D, Beiersmann C, Neuhann F, Moazen B, Lu G, Müller O.Risk factors for antibiotic resistance development in healthcare settings in China: a systematic review.Epidemiol Infect.2021 Jun 3;149:e141. doi:10.1017/S0950268821001254Medical Microbiology.Chapter 2 - structure.Flexbooks.org.Bacteria nutrition.Harvard T.H. Chan School of Public Health.The microbiome.Grant SS, Hung DT.Persistent bacterial infections, antibiotic tolerance, and the oxidative stress response.Virulence.2013 May 15;4(4):273-83. doi:10.4161/viru.23987
Microbiology Society.What are bacteria.
Duranti S, Longhi G, Ventura M, et al.Exploring the ecology of bifidobacteria and their genetic adaptation to the mammalian gut.Microorganisms. 2020;9(1):8. Published 2020 Dec 22. doi:10.3390/microorganisms9010008
Backer R, Rokem JS, Ilangumaran G, et al.Plant growth-promoting rhizobacteria: Context, mechanisms of action, and roadmap to commercialization of biostimulants for sustainable agriculture.Front Plant Sci. 2018;9:402666.
Pan M, Hidalgo-Cantabrana C, Goh YJ, Sanozky-Dawes R, Barrangou R.Comparative analysis ofLactobacillus gasseriandLactobacillus crispatusisolated from human urogenital and gastrointestinal tracts.Front Microbiol. 2020;10:3146. doi:10.3389/fmicb.2019.03146
Microbiology society.Streptomyces.
National Library of Medicine.Pseudomonas.
Talwar A, Tsang CA, Price SF, et al.Tuberculosis — United States, 2018.MMWR Morb Mortal Wkly Rep. 2019;68:257–262. doi:10.15585/mmwr.mm6811a2
Nemser SM, Doran T, Grabenstein M, et al.Investigation of listeria, salmonella, and toxigenic escherichia coli in various pet foods.Foodborne Pathog Dis. 2014;11(9):706-709. doi:10.1089/fpd.2014.1748
Martin JM.The mysteries of streptococcal pharyngitis.Curr Treat Options Pediatr. 2015;1(2):180-189. doi:10.1007/s40746-015-0013-9
King JM, Kulhankova K, Stach CS, Vu BG, Salgado-pabón W.Phenotypes and virulence among staphylococcus aureus. USA100, USA200, USA300, USA400, and USA600 Clonal Lineages. mSphere. 2016;1(3). doi:10.1128/CMR.00134-14
MedlinePlus.Immune response.
Onakpoya IJ, Walker AS, Tan PS, Spencer EA, Gbinigie OA, Cook J, Llewelyn MJ, Butler CC.Overview of systematic reviews assessing the evidence for shorter versus longer duration antibiotic treatment for bacterial infections in secondary care.PLoS One.2018 Mar 28;13(3):e0194858. doi:10.1371/journal.pone.0194858
Chen Q, Li D, Beiersmann C, Neuhann F, Moazen B, Lu G, Müller O.Risk factors for antibiotic resistance development in healthcare settings in China: a systematic review.Epidemiol Infect.2021 Jun 3;149:e141. doi:10.1017/S0950268821001254
Medical Microbiology.Chapter 2 - structure.
Flexbooks.org.Bacteria nutrition.
Harvard T.H. Chan School of Public Health.The microbiome.
Grant SS, Hung DT.Persistent bacterial infections, antibiotic tolerance, and the oxidative stress response.Virulence.2013 May 15;4(4):273-83. doi:10.4161/viru.23987
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