Myxococcus xanthus

All unapproved Citizendium articles may contain errors of fact, bias, grammar etc. A version of an article is unapproved unless it is marked as citable with a dedicated green template at the top of the page, as in this version of the 'Biology' article. Citable articles are intended to be of reasonably high quality. The participants in the Citizendium project make no representations about the reliability of Citizendium articles or, generally, their suitability for any purpose. This article is currently being developed as part of an Eduzendium student project in the framework of a course entitled Microbiology 201 at Queens College, CUNY. The course homepage can be found at CZ:Biol 201: General Microbiology. For the course duration, the article is closed to outside editing. Of course you can always leave comments on the discussion page. The anticipated date of course completion is May 21, 2009. One month after that date at the latest, this notice shall be removed. Besides, many other Citizendium articles welcome your collaboration!

Scientific classification

Description and significance

Myxococcus xanthus is a social organism, which are self-organized, saprotrophic and predatory. M. xanthus is a rod shaped, gram negative bacteria, which uses a form of gliding for locomotion. There's been recent discovery of two types of systems used for locomotion. The first system is type IV pilli, which is used as a type of hook. The second system is mucus secreting, which tend to form sites of focal adhesion. During starvation periods this bacteria has been discovered to use a form of chemotaxis signaling in order to produce and regulate multi-cellular rippling during predation. Predation takes place a multi-cellular synchronizing mechanism. The ability for this bacteria to communicate with others and be able to work together towards the targeted prey, makes it a good candidate for research. M. xanthus tends to form fruiting bodies. Within these fruiting bodies there are spores. These spores will germinate in order to return to a vegetative cycle as soon as conditions are favorable. M.xanthus is a predator to other bacteria, but harmless to humans.

Genome structure

M.xanthus is one of the largest prokaryotic genomes to be sequenced. Length of genome is 9,139,763 nt. Number of genes: 7456, Protein coding genes: 7331, Structural RNAs: 79, Pseudo genes:43, Topology: circular.

Cell structure and metabolism

M. xanthus has a life cycle which includes; predation, fruit bodies and swarming. Fruit bodies usually form from the cause of starvation, these bodies can then form into stress-resistant spores.

Ecology

M. xanthus is commonly found in soil. This bacteria lives in a multi-cellular unit.

Pathology

This bacteria is a predator of other bacteria, but non pathogenic. The fact that M. xanthus moves by chemotaxis and usually moves towards a prey resulted in the word "predataxis". M. xanthus is not a single unit when attacking a prey, rather there is a sense of cooperation. Predation of M. xanthus includes release of toxic and lytic substances. These substances can dragrade or paralyze the targeted prey.

Application to biotechnology

The unique feature of M.xanthus being predatory towards other bacteria, is of great use for studies. This feature has been hypothesis to be utilized in order to predate for other harmful bacteria.

Current research

Current locomotion studies have revealed that the synchronizing of both motor systems is due to spatial oscillation of motility proteins. M. xanthus predation tactics are being studied with results such as: a sort of cell reversal motion which cause a wave like effect, directing towards the prey. There is also a correlation between the ripple wavelength and amount of prey available. High amounts prey there are shorter wavelengths, lower amounts of prey cause a longer wavelength. Current research has positive results on the identification of the pathway responsible for chemotaxis in this bacteria. The assumed pathway is Frz, which activates FrCD, a chemotaxis protein.

References

<http://en.wikipedia.org/wiki/Myxococcus_xanthus>

<http://microbewiki.kenyon.edu/index.php/Mycoccus_xanthus>

<Genetic circuitry controlling motility behaviors of Myxococcus xanthus, Taˆ m Mignot1* and John R. Kirby2 >

<The social lifestyle of myxobacteria, Arthur L. Koch* and David White >

<http://www.medicine.uiowa.edu/CCOM/news/video-predataxis/>

<http://www.nytimes.com/2008/11/04/science/04obswarm.html?_r=1>

<Site-specific receptor methylation of FrzCD in Myxococcus xanthus is controlled by a tetra-trico peptide repeat (TPR) containing regulatory domain of the FrzF methyltransferase, Ansley E. Scott, Eric Simon, Samuel K. Park, Philip Andrews2 and David R. Zusman1*>

<http://www.ncbi.nlm.nih.gov/sites/entrez?Db=genome&Cmd=ShowDetailView&TermToSearch=250>