Peritrichous

Vibrio spp. are highly motile Gram-negative bacteria, mainly found in aquatic environments. Some Vibrios are meant for causing disease and morbidity in marine invertebrates and humans, whereas others are best studied for their symbiotic interactions. Vibrio spp. is motile because of the synthesis of flagella that rotates and propels the bacteria. Many species of Vibrio spp. synthesize monotrichous polar flagella (e.g., V. cholerae, V. alginolyticus); however, some synthesize peritrichous or lophotrichous flagella. 

Flagellar-mediated motility is connected to biological and cellular processes like those chemotaxis, biofilm formation, colonization, and virulence of Vibrio spp. This review is based on the polar flagellum and its regulation is referred to as Vibrio virulence and environmental persistence.

Artificial bacterial flagella are simply nonbiological structures whose design depends on that of bacterial flagella. They are mainly metallic and comprise two parts: a square, flathead and a helical tail. The head is magnetic and is composed of thin metal layers of chromium, nickel, and gold. The tail is usually a flat ribbon-like (nonmagnetic) metal helix. Applying a rotating magnetic field makes the head rotate, and the attached helical tail follows suit. This creates a spiral motion like that of a bacterial flagellum and generates thrust.

Types

There are usually three types of flagella that have so far been distinguished; bacterial, archaeal and eukaryotic. The major differences among these three types are discussed below:

Bacterial flagella: are generally helical filaments that can rotate like screws. They provide two different kinds of bacterial motility.

Archaeal flagella: are quite similar to bacterial flagella, but are different in many details and are mostly considered non-homologous.

Eukaryotic flagella: like those of animal, plant, and protists cells are made up of complex cellular projections that move back and forth. Eukaryotic flagella are classified along with eukaryotic motile cilia as undulipodia to determine their distinctive wavy appendage role in cellular function or motility. Primary cilia are immotile, and are not undulipodia; they possess a structurally different 9+0 axoneme rather than the 9+2 axoneme that is present in both flagella and motile cilia undulopodia.

Peritrichous

• The peritrichous arrangement of flagella is the arrangement in which the flagella are present throughout the body of the cell, all of which are directed in different ways.

• In the peritrichous arrangement, the flagella form a bundle that helps to move the cell towards the stimuli through the ‘run’ movement of the cell.

• In the case of repellent, a phosphorylation cascade is formed that changes the phosphorylation status of the regulator, CheY.

• The activated regulator is then able to interact directly with the motor switch proteins, resulting in the flagella rotating in the clockwise direction.

• The interaction has caused the destruction of bundles and separation of the flagella, which further changes the speed and direction of the movement.

• The Brownian motion of the cells helps them to reorient until the next stimulus is received randomly.

• Some of the examples of peritrichous arrangements of flagella are Escherichia coli, Bacillus subtilis, Salmonella, and Klebsiella.

Conclusion

The term ‘flagellum’ is a Latin term for whip indicating the long slender structure of the flagellum that is similar to a whip. Flagella are usually the primary structures of locomotion in many bacteria so that bacteria can move towards the most favourable environment. The movement of bacteria arises in response to different stimuli that enable them to adapt to various environmental conditions. In eukaryotic cells such as sperm, flagella are important for motility and lastly fertilisation. Flagella play a crucial role in the colonisation of tissue surfaces like a virulence factor to invade host tissues and develop within them. These are also vital for the non-pathogenic colonization of surfaces such as plant, soil, or animal surfaces. Here we come to an end of this topic. We hope that you were able to grasp a clear concept of the topic of peritrichous bacterial