
The Rhodospirillaceae are a family of
Proteobacteria
Proteobacteria is a major phylum
In biology, a phylum (; plural
The plural (sometimes list of glossing abbreviations, abbreviated ), in many languages, is one of the values of the grammatical number, grammatical category of number. The pl ...
. The majority are
purple nonsulfur bacteria, producing energy through
photosynthesis
Photosynthesis is a process used by plants and other organisms to convert
Conversion or convert may refer to:
Arts, entertainment, and media
* Conversion (Doctor Who audio), "Conversion" (''Doctor Who'' audio), an episode of the audio drama ' ...

; originally all purple nonsulfur bacteria were included here.
[George M. Garrity, Don J. Brenner, Noel R. Krieg, James T. Staley (Hrsg.): ''Bergey's manual of systematic bacteriology''. Vol. 2: ''The Proteobacteria Part C: The Alpha-, Beta-, Delta-, and Epsilonproteabacteria''. 2. Auflage. Springer, New York 2005, ][Martin Dworkin, Stanley Falkow, Eugene Rosenberg, Karl-Heinz Schleifer, Erko Stackebrandt: The Prokaryotes, A Handbook of the Biology of Bacteria''. Volume 5: Proteobacteria: Alpha and Beta Subclasses'' ]
They are often found in anaerobic aquatic environments, such as
mud
Mud is soil
Surface-water- gley developed in glacial till, Northern Ireland.">Northern_Ireland.html" ;"title="glacial till, Northern Ireland">glacial till, Northern Ireland.
Soil is a mixture of organic matter, minerals, gases, liquids, a ...

and
stagnant water
Water stagnation occurs when water stops Environmental flow, flowing. Stagnant water can be a major environmental hazard.
Dangers
Malaria and dengue are among the main dangers of stagnant water, which can become a breeding ground for the mosquito ...

, although they are able to survive in air.
[
This family also includes '' Magnetospirillum'', which contains tiny chains of ]magnetite
Magnetite is a mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure for ...

.[ These let it sense the Earth's ]magnetic field
A magnetic field is a vector field
In vector calculus and physics, a vector field is an assignment of a vector to each point in a subset of space. For instance, a vector field in the plane can be visualised as a collection of arrows with ...

, which runs downwards as well as north or south, to return to the bottom of a pond (magnetotaxis Magnetotaxis is a process implemented by a diverse group of gram negative bacteria
Gram-negative bacteria are bacteria
Bacteria (; common noun bacteria, singular bacterium) are a type of Cell (biology), biological cell. They constitute a l ...
). Similar magnetite chains found in Martian
A Martian is an inhabitant of the planet Mars or a Colonization of Mars, human colonist on Mars. Although the search for evidence of life on Mars continues, many science fiction writers have imagined what extraterrestrial life on Mars might be l ...

meteorite
A meteorite is a solid piece of debris from an object, such as a comet
A comet is an icy, small Solar System body
A small Solar System body (SSSB) is an object in the Solar System
The Solar SystemCapitalization of the name varie ...
s have been suggested as evidence of life on Mars.[Peter R. Buseck, Rafal E. Dunin-Borkowski, Bertrand Devouard, Richard B. Frankel, Martha R. McCartney, Paul A. Midgley, Mihály Pósfai, and Matthew Weyland: ''Magnetite morphology and life on Mars'' In: ''Proceedings of the National Academy of Sciences'' 2001 November 20; 98(24): 13490–13495]
Online
/ref>
References
Rhodospirillales
{{alphaproteobacteria-stub