**5. Biological importance**

*Pathogenic Bacteria*

**Figure 3.** *Quorum sensing.*

Cell density-dependent gene regulation phenomenon is otherwise called quorum sensing (QS). The chemical properties of signaling molecules associated with QS are differing; however gram-negative microbes most regularly utilize N-acylhomoserine lactones (AHLs). For instance, types of *Acidithiobacillus*, *Acinetobacter*, *Aeromonas*, *Agrobacterium*, *Brucella*, *Burkholderia*, *Erwinia*, *Enterobacter*, *Chromobacterium*, *Hafnia*, *Mesorhizobium*, *Methylobacter*, *Paracoccus*, *Pseudomonas*, *Ralstonia*, *Rhodobacter*, *Rhizobium*, *Rhanella*, *Serratia*, *Sinorhizobium*, *Vibrio*, and *Yersinia Williams* are referred to utilize AHLs as their major signaling molecules. In the biofilm arrangement as well as in the dispersal, QS assumes a noteworthy job. In *Rhodobactersphaeroides* (mutant cells), the addition of 7,8-cis-tetradecenoyl-HSL to the cell total brought about cell scattering prompting

There are many different types of microorganisms which are known for their property to form biofilm. These include both the gram-positive and gram-negative species. The gram-positive bacteria include *Listeria monocytogenes*, *Bacillus species*, *Staphylococcus species*, and *lactic acid bacteria*, which includes *Lactobacillus* 

*plantarum* and *Lactococcus lactis*. And the gram-negative species include *Escherichia coli* and *Pseudomonas aeruginosa*. It is also been observed that other bacteria such as *Cyanobacteria* have the ability to form the biofilms in the aqueous environments. The production of biofilms is also the property of microbes which are known to colonize the plants. These microbes include *Pseudomonas putida*, *Pseudomonas fluorescens*, and connected *pseudomonads*. They are mostly the plant-associated microorganisms and are known to be present on roots, leaves, and within the soil. This is the reason which gives them the property of producing

the development of free individual cells in suspension (**Figure 3**).

**4. Taxonomic diversity**

**8**
