Bacteria collective motion refers to the collective behavior of bacteria observed in the bacteria world.
Bacteria collective motion refers to the collective behavior of bacteria observed in the bacteria world.
| Part of a series on |
| Microbial and microbot movement |
|---|
 |
Collective motion (or collective behavior) is a common phenomenon in our daily life. From bird flocks to the human gathering, and from colonies of army ants to swimming bacteria, collective behaviors happens all the time.
The definition of collective motion varies slightly in different researches, but the core is the same. According to Tamás Vicsek et al., [1] collective behavior refers to the phenomenon that an individual unit’s action is dominated by the influence of the ‘‘others’’.
In a collective motion system, some key characteristics should be included: the units of the system should be similar to each other; the units should be moving with a nearly a constant absolute velocity and are able to change their direction; and the units in the system should be able to interact with fellow units and respond to environmental change.
The patterns of bacteria collective motion are very different from the motion pattern of an individual bacterium. When flagellated bacteria are moving in bulk liquid, where the locomotion of one individual doesn’t affect the others, this movement is called swimming. single Escherichia coli bacterium swims in a ‘run-and-tumble’ motion.
At a moist surface or in a thin liquid film, flagellated bacteria will exert another pattern, which is called swarming motility. [2] Bacteria swarming refers to a rapid cellular bacterial surface movement powered by rotating flagella. Key features of swarming bacteria are large-scale swirling and streaming motions.
During Escherichia coli swarming, in the edge area, the density of the bacteria is the lowest; in the peak area, the cell density is the highest, followed by falloff, where the density drops, and plateau 1 and 2, where the density remains almost the same. [3]
Many methods have been applied to visualize the collective motion of bacteria collective motion, but the most popular one is Particle image velocimetry (PIV).
Chemotaxis is the movement of an organism or entity in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment. This is important for bacteria to find food by swimming toward the highest concentration of food molecules, or to flee from poisons. In multicellular organisms, chemotaxis is critical to early development and subsequent phases of development as well as in normal function and health. In addition, it has been recognized that mechanisms that allow chemotaxis in animals can be subverted during cancer metastasis. The aberrant chemotaxis of leukocytes and lymphocytes also contribute to inflammatory diseases such as atherosclerosis, asthma, and arthritis. Sub-cellular components, such as the polarity patch generated by mating yeast, may also display chemotactic behavior.
A pilus is a hair-like appendage found on the surface of many bacteria and archaea. The terms pilus and fimbria can be used interchangeably, although some researchers reserve the term pilus for the appendage required for bacterial conjugation. All pili in the latter sense are primarily composed of pilin proteins, which are oligomeric.
Escherichia coli, also known as E. coli, is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most E. coli strains are harmless, but some serotypes (EPEC, ETEC etc.) can cause serious food poisoning in their hosts, and are occasionally responsible for food contamination incidents that prompt product recalls. The harmless strains are part of the normal microbiota of the gut, and can benefit their hosts by producing vitamin K2, (which helps blood to clot) and preventing colonisation of the intestine with pathogenic bacteria, having a mutualistic relationship. E. coli is expelled into the environment within fecal matter. The bacterium grows massively in fresh fecal matter under aerobic conditions for 3 days, but its numbers decline slowly afterwards.
A flagellum is a lash-like appendage that protrudes from the cell body of certain cells termed as flagellates. A flagellate can have one or several flagella. The primary function of a flagellum is that of locomotion, but it also often functions as a sensory organelle, being sensitive to chemicals and temperatures outside the cell.
In biology, quorum sensing is the ability to detect and respond to cell population density by gene regulation. As one example, quorum sensing (QS) enables bacteria to restrict the expression of specific genes to the high cell densities at which the resulting phenotypes will be most beneficial. Many species of bacteria use quorum sensing to coordinate gene expression according to the density of their local population. In a similar fashion, some social insects use quorum sensing to determine where to nest. Quorum sensing may also be useful for cancer cell communications.
Swarm behaviour, or swarming, is a collective behaviour exhibited by entities, particularly animals, of similar size which aggregate together, perhaps milling about the same spot or perhaps moving en masse or migrating in some direction. It is a highly interdisciplinary topic. As a term, swarming is applied particularly to insects, but can also be applied to any other entity or animal that exhibits swarm behaviour. The term flocking or murmuration can refer specifically to swarm behaviour in birds, herding to refer to swarm behaviour in tetrapods, and shoaling or schooling to refer to swarm behaviour in fish. Phytoplankton also gather in huge swarms called blooms, although these organisms are algae and are not self-propelled the way animals are. By extension, the term "swarm" is applied also to inanimate entities which exhibit parallel behaviours, as in a robot swarm, an earthquake swarm, or a swarm of stars.
Proteus is a genus of Gram-negative Proteobacteria. Proteus bacilli are widely distributed in nature as saprophytes, being found in decomposing animal matter, sewage, manure soil, the mammalian intestine, and human and animal feces. They are opportunistic pathogens, commonly responsible for urinary and septic infections, often nosocomial.
Proteus mirabilis is a Gram-negative, facultatively anaerobic, rod-shaped bacterium. It shows swarming motility and urease activity. P. mirabilis causes 90% of all Proteus infections in humans. It is widely distributed in soil and water. Proteus mirabilis can migrate across the surface of solid media or devices using a type of cooperative group motility called swarming. Proteus mirabilis is most frequently associated with infections of the urinary tract, especially in complicated or catheter-associated urinary tract infections.
Microbial intelligence is the intelligence shown by microorganisms. The concept encompasses complex adaptive behavior shown by single cells, and altruistic or cooperative behavior in populations of like or unlike cells mediated by chemical signalling that induces physiological or behavioral changes in cells and influences colony structures.
The bacterium, despite its simplicity, contains a well-developed cell structure which is responsible for some of its unique biological structures and pathogenicity. Many structural features are unique to bacteria and are not found among archaea or eukaryotes. Because of the simplicity of bacteria relative to larger organisms and the ease with which they can be manipulated experimentally, the cell structure of bacteria has been well studied, revealing many biochemical principles that have been subsequently applied to other organisms.
Myxococcus xanthus is a gram-negative, rod-shaped species of myxobacteria that exhibits various forms of self-organizing behavior in response to environmental cues. Under normal conditions with abundant food, it exists as a predatory, saprophytic single-species biofilm called a swarm. Under starvation conditions, it undergoes a multicellular development cycle.
Swarming motility is a rapid and coordinated translocation of a bacterial population across solid or semi-solid surfaces, and is an example of bacterial multicellularity and swarm behaviour. Swarming motility was first reported by Jorgen Henrichsen and has been mostly studied in genus Serratia, Salmonella, Aeromonas, Bacillus, Yersinia, Pseudomonas, Proteus, Vibrio and Escherichia.
Bacterial motility is the ability of bacteria to move independently, using metabolic energy. Most motility mechanisms which evolved among bacteria also evolved in parallel among the archaea.
Bacterial adhesion involves the attachment of bacteria on the surface. This interaction plays an important role in natural system as well as in environmental engineering. The attachment of biomass on the membrane surface will result in membrane fouling, which can significantly reduce the efficiency of the treatment system using membrane filtration process in wastewater treatment plants. The low adhesion of bacteria to soil is essential key for the success of in-situ bioremediation in groundwater treatment. However, the contamination of pathogens in drinking water could be linked to the transportation of microorganisms in groundwater and other water sources. Controlling and preventing the adverse impact of the bacterial deposition on the aquatic environment need a deeply understanding about the mechanisms of this process. DLVO theory has been used extensively to describe the deposition of bacteria in many current researches.
Gliding motility is a type of translocation used by microorganisms that is independent of propulsive structures such as flagella, pili, and fimbriae. Gliding allows microorganisms to travel along the surface of low aqueous films. The mechanisms of this motility are only partially known.
Paenibacillus vortex is a species of pattern-forming bacteria, first discovered in the early 1990s by Eshel Ben-Jacob's group at Tel Aviv University. It is a social microorganism that forms colonies with complex and dynamic architectures. P. vortex is mainly found in heterogeneous and complex environments, such as the rhizosphere, the soil region directly influenced by plant roots.
Microorganisms engage in a wide variety of social interactions, including cooperation. A cooperative behavior is one that benefits an individual other than the one performing the behavior. This article outlines the various forms of cooperative interactions seen in microbial systems, as well as the benefits that might have driven the evolution of these complex behaviors.
Self-propelled particles (SPP), also referred to as self-driven particles, are terms used by physicists to describe autonomous agents, which convert energy from the environment into directed or persistent motion. Natural systems which have inspired the study and design of these particles include walking, swimming or flying animals. Other biological systems include bacteria, cells, algae and other micro-organisms. Generally, self-propelled particles often refer to artificial systems such as robots or specifically designed particles such as swimming Janus colloids, bimetallic nanorods, nanomotors and walking grains. In the case of directed propulsion, which is driven by a chemical gradient, this is referred to as chemotaxis, observed in biological systems, e.g. bacteria quorum sensing and ant pheromone detection, and in synthetic systems, e.g. enzyme molecule chemotaxis and enzyme powered hard and soft particles.
Paenibacillus dendritiformis is a species of pattern-forming bacteria, first discovered in the early 90s by Eshel Ben-Jacob's group. It is a social microorganism that forms colonies with complex and dynamic architectures. The genus Paenibacillus comprises facultative anaerobic, endospore-forming bacteria originally included within the genus Bacillus and then reclassified as a separate genus in 1993. Bacteria belonging to this genus have been detected in a variety of environments such as: soil, water, rhizosphere, vegetable matter, forage and insect larvae.
Bacterial morphological plasticity refers to changes in the shape and size that bacterial cells undergo when they encounter stressful environments. Although bacteria have evolved complex molecular strategies to maintain their shape, many are able to alter their shape as a survival strategy in response to protist predators, antibiotics, the immune response, and other threats.