A Quick Guide on Bacterial Cell Wall

The bacterial cell is a complicated, honeycomb structure that is required for cellular structures and structural stability in most bacteria. Due to its importance for most bacteria and absence from the eukaryotic world, the cell wall has long been a focus of study, making it a perfect target for some of our most potent medicines. Bacterial cell walls vary from plant and fungal cell walls, which are composed of cellulose and chitin, respectively.  The cell wall’s primary roles are to give structure, support, and protection to the cell.

A Quick Guide on Bacterial Cell Wall

Now we will learn in depth about what do we mean by cell wall, bacterial cell wall and lastly, at structure of bacterial cell wall along with what bacterial cell wall is made up of

Cell wall

The cell wall is a semi-rigid, thick protective barrier that surrounds the cell membrane of certain kinds of cells for protection and shape definition. The stiffness and strength needed by the cell membrane cannot be provided alone by the cell membrane. 

Cells are the building blocks of all living things. All critical tasks, including metabolism, reproduction, and excretion, are carried out by cells. Organelles are intracellular structures that make up the cell. Organelles are small structures implanted in the cytoplasm that provide specialised roles. A plasma membrane (or cell membrane) surrounds the cell, separating the contents from the external environment. 

A cell wall, on the other hand, is a structural layer next to the cell membrane that serves to provide the cell rigidity and protection from mechanical stress. Its primary job is to provide rigidity, strength, and mechanical stress resistance to the cell. Plants, fungi, protists (especially moulds and algae), and most bacteria (with the exception of mycoplasma and L-form bacteria) are examples of creatures possessing cell walls. Cell walls are absent in animals and heterotrophic protists.

Bacterial cell wall

Outside of the cell membrane is a cell wall, which is present in all species, not only bacteria. It’s an extra layer with a semi-rigid structure that often gives some strength that the cell membrane lacks.

Types-

Peptidoglycan is a component found in both gram positive and gram-negative cell walls (also known as murein). Except in the cell walls of bacteria, this chemical has never been discovered anywhere else on Earth. However, both forms of bacterial cell walls include additional elements, making the bacterial cell wall a complicated structure in general, especially when compared to eukaryotic microbe cell walls. Eukaryotic microorganisms’ cell walls are often made up of a single element, such as cellulose in algal cell walls of chitin in fungus cell walls.

Functions- 

In addition to providing overall cell strength, the bacterial cell wall serves a variety of roles. It also aids in the maintenance of cell shape, which is critical for the cell’s ability to grow, reproduce, collect nutrients, and migrate. As the cell travels from one environment to another or transfers nutrients from its surroundings, it protects the cell against osmotic lysis. 

Because water may readily pass through both the cell membrane and the cell wall, the cell is vulnerable to osmotic imbalance, which might exert pressure on the plasma membrane, which is relatively fragile. According to studies, the internal pressure of a cell is comparable to the pressure inside a completely inflated automobile tire. 

That’s a lot of pressure to take on the plasma membrane! For gram negative bacteria, the cell wall may block out specific compounds, such as toxins. Finally, for some bacterial pathogens, the bacterial cell wall may contribute to pathogenicity, or the potential of the cell to cause illness.

Structure of bacterial cell wall

Peptidoglycan (PG) is a mesh of polysaccharide strands (formed of a poly-[N-acetylglucosamine (GlcNAc)-N-acetylmuramic acid (MurNAc) backbone) cross-linked through short peptide bridges bonded to MurNAc residues. The cytoplasm’s exterior face is where PG is made. The lipid-linked disaccharide-pentapeptide precursor lipid II is synthesized in the cytoplasm, then translocated to the exterior of the cell via flippases (MurJ and/or Amj), and lastly assembled by penicillin-binding proteins (PBPs) and Shape, Elongation, Division, and Sporulation (SEDS) proteins. 

Polymerization of the GlcNAc-MurNAc-pentapeptide through glycosyltransferase processes catalyzed by class A PBPs and SEDS proteins, and crosslinking of the peptide sidestems into a tight meshwork by class A and B PBPs and L,D-transpeptidases in a not-yet-understood manner 

Additionally, secondary cell wall polymers, such as wall teichoic acids (polyol-phosphate polymers) or capsule polysaccharides that are covalently bonded to PG, may be used to adorn the PG mesh. Layers of polysaccharides and long-chain lipids are added to the PG layer in mycobacteria, making the cell wall structure even more complicated, this is what bacterial cell wall is made up of.

Conclusion

In this article we got to know about what we mean by cell wall, bacterial cell wall, its types, functions and at last at structure of bacterial cell wall. In addition to providing overall cell strength, the bacterial cell wall serves various other purposes. The bacterial cell wall also contains peptidoglycan, which is what bacterial cell wall is made up of, is an essential protective barrier for bacterial cells that encapsulates the cytoplasmic membrane of both Gram-positive and Gram-negative bacterial cells, and it helps maintain cell shape, which is important for how the cell will grow, reproduce, obtain nutrients, and move. Peptidoglycan is a complex structure made up of polymeric carbohydrates and amino acids that is hard and well preserved.