The key difference between atypical bacteria and typical bacteria is that atypical bacteria is a group of bacteria that do not have a cell wall while typical bacteria is a group of bacteria that have a cell wall.
Bacteria are tiny microorganisms. They come in different shapes and sizes. Bacteria also live in various environments. Some bacteria are resistant towards immune defence and cause different diseases once they enter the body. Moreover, some of them are also resistant to antibiotics, which are usually used to cure diseases. A bacterial cell wall is an external covering that provides additional strength to the cell. It is made up of peptidoglycan and is present in both Gram-positive and Gram-negative bacteria. Atypical and typical bacteria are two different types of bacteria classified based on the presence of cell walls. Atypical bacteria do not possess a cell wall while typical bacteria have a cell wall.
CONTENTS
1. Overview and Key Difference
2. What is Atypical Bacteria
3. What is Typical Bacteria
4. Similarities – Atypical Bacteria and Typical Bacteria
5. Atypical Bacteria vs. Typical Bacteria in Tabular Form
6. FAQ – Atypical Bacteria and Typical Bacteria
7. Summary – Atypical Bacteria vs. Typical Bacteria
What are Atypical Bacteria?
Atypical bacteria are a type of bacteria that do not contain a cell wall. They are not stained by Gram staining due to a lack of cell wall and hence remain colouless. Atypical bacteria are also known as incomplete bacteria and are normally obligate parasites. These bacteria need a host for their survival.
Figure 01: Atypical Bacteria
Atypical bacteria are recognized as zoonotic as they can transfer from animals to humans and vice versa. Transmission of atypical bacteria does take place through air. Some of the very popular diseases caused by atypical bacteria are bird flu and atypical pneumonia. Moreover, some examples of atypical bacteria are Legionella, Chlamydia, Mycoplasma, and Rickettsia.
What are Typical Bacteria?
Typical bacteria are known as complete bacteria. They have a cell wall surrounding the cell membrane. Based on the properties of the cell wall, they are classified as either Gram-positive or Gram-negative. Apart from the cell wall, some of them also have a capsule surrounding the cell wall.
Figure 02: Typical Bacteria
Some examples of typical bacteria are Streptococcus, Staphylococcus, Klebsiella, Haemophilia, and Moraxella. These bacteria can cause diseases like Pneumonia, strep throat, skin infections, etc.
What are the Similarities Between Atypical Bacteria and Typical Bacteria?
- Atypical and typical bacteria are two different types of bacteria classified based on the presence of cell walls.
- These bacteria are prokaryotes.
- Both types of bacteria are single-cell organisms or unicellular organisms.
- They have 70S ribosomes, and their genetic material appears in the cytosol, and their biochemical reactions occur in the cytosol.
- They can cause diseases in humans.
What is the Difference Between Atypical Bacteria and Typical Bacteria?
Atypical bacteria do not have a cell wall, while typical bacteria have a cell wall. This is the key difference between atypical bacteria and typical bacteria. Furthermore, atypical bacteria are incomplete bacteria. On the other hand, typical bacteria are complete bacteria. In gram staining, atypical bacteria remain colourless, while typical bacteria stain in either pink or purple.
The infographic below presents the differences between atypical bacteria and typical bacteria in tabular form for side-by-side comparison.
FAQ: Atypical Bacteria and Typical Bacteria
What are the characteristics of atypical bacteria?
Atypical bacteria lack a cell wall; hence, they do not stain in gram staining.
What are examples of atypical bacteria?
Chlamydia, Mycoplasma, and Legionella are several examples.
Which bacteria can not be Gram-stained?
Atypical bacteria like mycoplasma can not be Gram-stained.
Summary – Atypical Bacteria vs. Typical Bacteria
Bacteria can be divided into two kinds based on the presence of cell walls as atypical and typical bacteria. Atypical bacteria are known as incomplete bacteria. These bacteria do not have cell walls, unlike common bacteria. Moreover, atypical bacteria are known to be zoonotic. Typical bacteria are the ones that commonly learn in biology. Typical bacteria contain cellular walls and reproduce through cell division. Furthermore, unlike atypical bacteria, typical bacteria can be stained through Gram staining. This summarizes the difference between atypical and typical bacteria.
Reference:
1. “Atypical Bacteria – An Overview.” ScienceDirect.
2. “Atypical Bacterial Pneumonia.” Statpearls – NCBI Bookshelf.
Image Courtesy:
1. “Legionella Plate 01” By CDC/James Gathany – CDC Public Health Image Library (Public Domain) via Commons Wikimedia
2. “OSC Microbio 03 03 ProkCell” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia