**1. Introduction**

In the years which pursued the historical backdrop of microbiology, microscopic organisms have been for the most part contemplated as planktonic (free-floating) forms, the investigation of which contributed particularly to the comprehension of fundamental physiological procedures. It was just late 1960s and mid-1970s when the broad physical and chemical examinations of surface-attached microbes began coming up and the prevalence of surface-related microorganisms (biofilms) was perceived. A significant part of the prior work on biofilm characterization depended on the instruments, for example, scanning electron microscopy and standard microbiological culture procedures. The utilization of scanning electron microscopy by scientists uncovered that the biofilms are made out of a blend of various microorganisms; and the matrix material was predominantly made out of polysaccharide. The first genuine examination of biofilm was made by Costerton JW and KJ in 1978 when their examinations demonstrated that numerous microorganisms spend their most part of life inside surface-attached, sessile networks encased in a polymer network [1].

Initially the studies on biofilm were mostly focused on the structure of the polymer network or "glycocalyx" which was later portrayed by Costerton as an ion exchange network, thought to trap supplements from the surroundings [1]. Costerton found that the glycocalyx was a hydrated polyanionic polysaccharide network created by the polymerases inserted in the lipopolysaccharide part of bacterial cell wall [2]. In a watery situation (at the strong/fluid interface), biofilm generation assumes a noteworthy role in the assimilation and convergence of natural and

inorganic supplements. In addition, the biofilm provides a physical barrier that ensures incomplete protection against antibacterial substances.

During the 1990s, researchers started to comprehend the complex association of bacterial biofilm network. With the quick advances in the molecular technologies and microscopic techniques and systems, empowering extensive investigations of the biofilm method of life, there has been a striking advancement of biofilm understanding in late years. The biofilm can be framed by a solitary bacterial species; be that as it may, in many biological systems, biofilm comprises of heterogeneous networks of microorganism including bacteria, fungi, algae, and protozoa. Biofilm arrangement usually happens when microorganisms attach to surfaces in fluid conditions and begin discharging extracellular fluid like slimy material that can anchor them to a variety of materials including metals, plastics, soil particles, medical implant materials, and tissue. Microbial biofilm arrangement is known to be a successive bacterial development process and is managed by a progression of hereditary and phenotypic determinants. Accurate screening strategies, for example, isolation of biofilm defective mutants, have contributed incredibly to understanding the hereditary qualities of biofilm formative procedure; furthermore, noteworthy data is included in the hereditary premise of biofilm development.

A biofilm is known to have the involvement of many associations of microorganisms which leads to the adherence of the cells to one another and also to the surface where they are growing [3]. These adherent cells become installed inside a slimy extracellular network that is made out of extracellular polymeric substances (EPS). The cells inside the biofilm produce the EPS components, which are ordinarily a polymeric aggregation of extracellular polysaccharides, proteins, lipids, and DNA [3].

Biofilms may form on living or nonliving surfaces and are common in natural, industrial, and hospital settings [4]. The microbial cells developing in a biofilm are physiologically distinct from planktonic cells of a similar life form, which, on the other hand, are unicellular which have the ability to buoy or swim in a liquid medium. Biofilms can also grow on the teeth structure of many creatures in the form of dental plaque. This dental plaque then leads to the oral diseases of tooth decay and gum illness.

Microbes form a biofilm by the contribution of many different factors which somehow help in the recognition of sites of attachments on a surface, help them to find the nutritional sources, or, in some cases, help to develop resistance to

**5**

*Development of Biofilms for Antimicrobial Resistance DOI: http://dx.doi.org/10.5772/intechopen.90062*

functioning of the genes.

appends to a surface (**Figure 1**).

ing their cell griping structures such as pili.

in the case of bacteria having motility.

**2. Origin and formation**

**2.1 Origin**

**2.2 Formation**

antibiotics. When a bacterial cell develops the property to form biofilm, it then undergoes phenotypic changes. These phenotypic changes also bring a change in the

A biofilm structure can be elucidated as hydrogel, made up of polymer which contains the dry mass enclosed in the water. Biofilms are layers formed of bacterial sludge along with the naturally occurring frameworks. This whole organization of network gives a look of well-structured meshwork of cells. Biofilms can connect to a surface, for example, a tooth, rock, or surface, and may incorporate a single microorganism category or various gatherings of microorganisms. The biofilm microscopic organisms can share nutrients and are shielded from harmful factors in the environment, for example, antitoxins, and a host body's insusceptible framework. A biofilm for the most part starts to frame whenever a free-swimming bacterium

Biofilms are known to have emerged on the primitive Earth for the purpose of defense for the prokaryotes at that time because the condition of the Earth in the early ages was very harsh and difficult for the survival of prokaryotic organism. Biofilms provide the prokaryotic cells with homeostatic conditions which empowers them with the advancement of complex interactions between the cells having biofilm.

The arrangement of a biofilm starts with the connection of free-skimming microorganisms to a surface [5]. Initially, the microbes of a biofilm may adhere tightly to the surface with the help of hydrophobic interactions and van der Waals forces. If the other colony-forming microbes are not isolated from the surface instantly, then they quickly attach themselves to the surface permanently by utiliz-

Hydrophobicity has been observed to have effect on the ability of the microbes in the formation of biofilms. Microorganisms which have high amount of hydrophobicity are seen to have low amount of repulsive forces between the adherent surface and the attaching bacterium. In some cases, the microbes face difficulty in binding to the surface properly. This is because of their restricted motility, but however they can still adhere themselves to the matrix surface and to the other microbes which were initially present. The microbes having nil motility can neither attach to the surfaces nor have the ability to aggregate with each other effectively as that seen

In the process of surface colonization, the microbes have the ability to communicate by using the products of quorum sensing (QS). One of these products is N-acyl homoserine lactone (AHL). Once the cellular colonization starts, the development of biofilm also initiates by the combined effect of cell division and cell recruitment. The bacterial biofilms are mostly enclosed in the matrices made up of polysaccharides. Apart from the polysaccharides, these adherent matrices may also contain some other components such as different substances from the surrounding environment such as blood segments including fibrin and erythrocytes, minerals, particles of soil, and many other small substances. After all this comes the last phase of the arrangement of biofilm. This last stage is known as dispersion. Dispersion has been recognized as the stage in which the biofilm completely forms and may undergo some variations in shape and size.

**Figure 1.** *Biofilm on the septum.*

*Development of Biofilms for Antimicrobial Resistance DOI: http://dx.doi.org/10.5772/intechopen.90062*

antibiotics. When a bacterial cell develops the property to form biofilm, it then undergoes phenotypic changes. These phenotypic changes also bring a change in the functioning of the genes.

A biofilm structure can be elucidated as hydrogel, made up of polymer which contains the dry mass enclosed in the water. Biofilms are layers formed of bacterial sludge along with the naturally occurring frameworks. This whole organization of network gives a look of well-structured meshwork of cells. Biofilms can connect to a surface, for example, a tooth, rock, or surface, and may incorporate a single microorganism category or various gatherings of microorganisms. The biofilm microscopic organisms can share nutrients and are shielded from harmful factors in the environment, for example, antitoxins, and a host body's insusceptible framework. A biofilm for the most part starts to frame whenever a free-swimming bacterium appends to a surface (**Figure 1**).

## **2. Origin and formation**

#### **2.1 Origin**

*Pathogenic Bacteria*

decay and gum illness.

inorganic supplements. In addition, the biofilm provides a physical barrier that

During the 1990s, researchers started to comprehend the complex association of bacterial biofilm network. With the quick advances in the molecular technologies and microscopic techniques and systems, empowering extensive investigations of the biofilm method of life, there has been a striking advancement of biofilm understanding in late years. The biofilm can be framed by a solitary bacterial species; be that as it may, in many biological systems, biofilm comprises of heterogeneous networks of microorganism including bacteria, fungi, algae, and protozoa. Biofilm arrangement usually happens when microorganisms attach to surfaces in fluid conditions and begin discharging extracellular fluid like slimy material that can anchor them to a variety of materials including metals, plastics, soil particles, medical implant materials, and tissue. Microbial biofilm arrangement is known to be a successive bacterial development process and is managed by a progression of hereditary and phenotypic determinants. Accurate screening strategies, for example, isolation of biofilm defective mutants, have contributed incredibly to understanding the hereditary qualities of biofilm formative procedure; furthermore, noteworthy data is included in the hereditary premise of biofilm development.

A biofilm is known to have the involvement of many associations of microorganisms which leads to the adherence of the cells to one another and also to the surface where they are growing [3]. These adherent cells become installed inside a slimy extracellular network that is made out of extracellular polymeric substances (EPS). The cells inside the biofilm produce the EPS components, which are ordinarily a polymeric aggregation of extracellular polysaccharides, proteins, lipids, and DNA [3]. Biofilms may form on living or nonliving surfaces and are common in natural, industrial, and hospital settings [4]. The microbial cells developing in a biofilm are physiologically distinct from planktonic cells of a similar life form, which, on the other hand, are unicellular which have the ability to buoy or swim in a liquid medium. Biofilms can also grow on the teeth structure of many creatures in the form of dental plaque. This dental plaque then leads to the oral diseases of tooth

Microbes form a biofilm by the contribution of many different factors which somehow help in the recognition of sites of attachments on a surface, help them to find the nutritional sources, or, in some cases, help to develop resistance to

ensures incomplete protection against antibacterial substances.

**4**

**Figure 1.**

*Biofilm on the septum.*

Biofilms are known to have emerged on the primitive Earth for the purpose of defense for the prokaryotes at that time because the condition of the Earth in the early ages was very harsh and difficult for the survival of prokaryotic organism. Biofilms provide the prokaryotic cells with homeostatic conditions which empowers them with the advancement of complex interactions between the cells having biofilm.

#### **2.2 Formation**

The arrangement of a biofilm starts with the connection of free-skimming microorganisms to a surface [5]. Initially, the microbes of a biofilm may adhere tightly to the surface with the help of hydrophobic interactions and van der Waals forces. If the other colony-forming microbes are not isolated from the surface instantly, then they quickly attach themselves to the surface permanently by utilizing their cell griping structures such as pili.

Hydrophobicity has been observed to have effect on the ability of the microbes in the formation of biofilms. Microorganisms which have high amount of hydrophobicity are seen to have low amount of repulsive forces between the adherent surface and the attaching bacterium. In some cases, the microbes face difficulty in binding to the surface properly. This is because of their restricted motility, but however they can still adhere themselves to the matrix surface and to the other microbes which were initially present. The microbes having nil motility can neither attach to the surfaces nor have the ability to aggregate with each other effectively as that seen in the case of bacteria having motility.

In the process of surface colonization, the microbes have the ability to communicate by using the products of quorum sensing (QS). One of these products is N-acyl homoserine lactone (AHL). Once the cellular colonization starts, the development of biofilm also initiates by the combined effect of cell division and cell recruitment. The bacterial biofilms are mostly enclosed in the matrices made up of polysaccharides. Apart from the polysaccharides, these adherent matrices may also contain some other components such as different substances from the surrounding environment such as blood segments including fibrin and erythrocytes, minerals, particles of soil, and many other small substances. After all this comes the last phase of the arrangement of biofilm. This last stage is known as dispersion. Dispersion has been recognized as the stage in which the biofilm completely forms and may undergo some variations in shape and size.
