Bacteria are 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 is found 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 Behavior and Names
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:
- Bifidobacteria: Found in the human intestinal tract and play a role in gut health
- Rhizobacteria: Live in soil and help plants grow
- Lactobacillus: Live in the gut and play a role in digestion
- Streptomyces: Help the body produce antibodies to fight off infections
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:
- Pseudomonas aeruginosa: Can cause blood infections and pneumonia
- Mycobacterium tuberculosis: Causes tuberculosis
- Listeria, salmonella, and Escherichia coli (E. coli): Foodborne bacteria that can cause infections, illness, or typhoid
- Streptococcal: Can cause strep throat
- Staphylococcus: Can cause staph infections
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?
“Bacterial” is the adjective used to describe something that is driven by the presence of bacteria, such as in the term “bacterial infection.” When harmful bacteria enter the body and begin dividing and multiplying, they become overgrown and can cause significant damage to cells and tissues.
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 require antibiotic 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 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 needed
- Insufficient regulation of specific antibiotics
- Poor patient adherence when given antibiotics
Basic Bacteria Biology
Bacteria is split up into five different classifications, including:
- Comma (vibrios)
- Corkscrew (spirochaetes)
- Rod (bacilli)
- Spherical (cocci)
- Spiral (spirilla)
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:
- The capsule, which is a layer surrounding the outside walls of bacteria
- The cell wall, which gives bacteria their shape
- The plasma membrane, which helps to transport chemicals and generate energy within the cell
- Cytoplasm, which is a gel-like substance that contains the genetic material of bacteria
- DNA, which provides instructions that encourage the proper function of bacteria
- Ribosomes, which are the parts of the cell that synthesize protein
- Flagellum, which are hairlike strands that help bacteria move around
- Pili, which are more hairlike growths that allow it to stick to other cells to transfer genetic material
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.
How to Support Bacteria in the Gut
The gut is home to 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.
The primary way to support healthy bacteria in the gut is by providing the nutrients needed to thrive and do its job. That means ensuring that you’re getting enough fiber, which is what gut bacteria feed on, and other nutrients.
Types of fiber that help to encourage a healthy balance of gut bacteria include:
- Gums
- Pectins
- Resistant starches
- Sugars from fruits and vegetables
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.
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.
Both harmful and helpful bacteria are classified mainly by their shape. Other characteristics include their habitat and what they eat to survive. While there are good and bad bacteria, harmful bacteria should be avoided as best as possible through proper handwashing techniques, avoiding eating or drinking contaminated foods or water, and staying away from others who are sick.
