Bradyrhizobium

***Bradyrhizobium*** is a genus of Gram-negative soil bacteria that naturally occur as free-living soil bacteria or in symbiotic relationships with legumes. _Bradyrhizobium_ is known for nitrogen fixation, which converts atmospheric nitrogen into ammonia (N<sub>2</sub> - NH<sub>3</sub>). This process allows plants and other organisms to use organic compounds, such as nitrates, more readily. Nitrogen-fixing bacteria such as _Bradyrhizobium_ are crucial to chemical cycles in the soil.

### Ecology

_Bradyrhizobium_ species are Gram-negative, rod-shaped (also called bacilli) with a flagella (like a tail) to help them move through their environment. Gram-negative bacteria are smaller types of bacteria with thin cell walls that are sensitive to drought or water stress. They are commonly found in the soil where they can form relationships with plant roots such as peas, clover, and other legumes in a mutually beneficial, or symbiotic, relationship. In exchange for their nitrogen fixation, the _Bradyrhizobium_ benefit from carbohydrates made by the plant. They are also common in forest soils, although these species tend not to fix nitrogen.

### Accepted species

_Bradyrhizobium_ genus comprises the following species:

- _B. agreste_ <small>Klepa _et al_. 2021</small>
- _B. algeriense_ <small>Ahnia _et al_. 2019</small>
- _B. americanum_ <small>Ramírez-Bahena _et al_. 2017</small>
- _B. amphicarpaeae_ <small>Bromfield _et al_. 2019</small>
- _B. arachidis_ <small>Wang _et al_. 2013</small>
- _B. archetypum_ <small>Helene _et al_. 2020</small>
- _B. australiense_ <small>Helene _et al_. 2020</small>
- _B. betae_ <small>Rivas _et al_. 2004</small>
- _B. cajani_ <small>Araújo _et al_. 2017</small>
- _B. canariense_ <small>Vinuesa _et al_. 2005</small>
- _B. centrosematis_ <small>corrig. Ramírez-Bahena _et al_. 2017</small>
- _B. cosmicum_ <small>Wasai-Hara _et al_. 2020</small>
- _B. cytisi_ <small>Chahbourne _et al_. 2011</small>
- _B. daqingense_ <small>Wang JY _et al_. 2012</small>
- _B. denitrificans_ <small>(Hirsch and Müller 1986) van Berkum _et al_. 2011</small>
- _B. diazoefficiens_ <small>Delamuta _et al_ 2013</small>
- _B. diversitatis_ <small>Serenato Klepa _et al_. 2021</small>
- _B. elkanii_ <small>Kuykendall _et al_. 1993</small>
- _B. embrapense_ <small>Delamuta _et al._2015</small>
- _B. erythrophlei_ <small>Yao _et al_. 2015</small>
- _B. ferriligni_ <small>Yao _et al_. 2015</small>
- _B. frederickii_ <small>de Oliveira Urquiaga _et al_. 2019</small>
- _B. ganzhouense_ <small>Lu _et al_. 2014</small>
- _B. glycinis_ <small>Serenato Klepa _et al_. 2021</small>
- _B. guangdongense_ <small>Li _et al_. 2015</small>
- _B. guangxiense_ <small>Li _et al_. 2015</small>
- _B. hipponense_ <small>Rejili _et al_. 2020</small>
- _B. huanghuaihaiense_ <small>Zhang _et al_. 2012</small>
- _B. icense_ <small>Durán _et al_. 2014</small>
- _B. ingae_ <small>da Silva _et al_. 2014</small>
- _B. iriomotense_ <small>Islam _et al_. 2010</small>
- _B. ivorense_ <small>Fossou _et al_. 2020</small>
- _B. japonicum_ <small>(Kirchner 1896) Jordan 1982</small>
    - symbiovar _genistearum_
    - symbiovar _glycinearum_
- _B. jicamae_ <small>Ramírez-Bahena _et al_. 2009</small>
- _B. kavangense_ <small>Lasse gronemeyer et al. 2015</small>
- _B. lablabi_ <small>Chang _et al_. 2011</small>
- _B. liaoningense_ <small>Xu _et al_. 1995</small>
- _B. lupini_ <small>Peix _et al_. 2015</small>
- _B. manausense_ <small>Silva _et al_. 2014</small>
- _B. mercantei_ <small>Helene _et al_. 2017</small>
- _B. murdochi_ <small>Helene _et al_. 2020</small>
- _B. namibiense_ <small>Grönemeyer _et al_. 2017</small>
- _B. nanningense_ <small>Li _et al_. 2020</small>
- _B. neotropicale_ <small>Zilli _et al_. 2014</small>
- _B. niftali_ <small>Klepa _et al_. 2019</small>
- _B. nitroreducens_ <small>Jang _et al_. 2020</small>
- _B. oligotrophicum_ <small>(Ohta and Hattori 1985) Ramírez-Bahena _et al_. 2013</small>
- _B. ottawaense_ <small>Yu _et al_. 2014</small>
- _B. pachyrhizi_ <small>Ramírez-Bahena _et al_. 2009</small>
- _B. paxllaeri_ <small>Durán _et al_. 2014</small>
- _B. retamae_ <small>Guerrouj _et al_. 2013</small>
- _B. rifense_ <small>Chahboune _et al_. 2012</small>
- _B. ripae_ <small>Bünger _et al_. 2018</small>
- _B. shewense_ <small>Aserse _et al_. 2018</small>
- _B. stylosanthis_ <small>Marçon Delamuta _et al_. 2016</small>
- _B. subterraneum_ <small>Gronemeyer _et al_. 2015</small>
- _B. symbiodeficiens_ <small>Bromfield _et al_. 2020</small>
- _B. tropiciagri_ <small>Delamuta et al. 2015</small>
- _B. vignae_ <small>Grönemeyer _et al_. 2016</small>
- _B. viridifuturi_ <small>Helene et al. 2015</small>
- _B. yuanmingense_ <small>Yao _et al_. 2002</small>

### Provisional Species

The following species have been published, but not validated according to the Bacteriological Code

- "_B. brasilense_" <small>Martins da Costa _et al_. 2017</small>
- "_B. campsiandrae_" <small>Cabral Michel _et al_. 2021</small>
- "_B. centrolobii_" <small>Michel _et al_. 2017</small>
- "_B. forestalis_" <small>Martins da Costa _et al_. 2018</small>
- "_B. guangzhouense_" <small>Li _et al_. 2019</small>
- "_B. macuxiense_" <small>Michel _et al_. 2017</small>
- "_B. sacchari_" <small>de Matos _et al_. 2017</small>
- "_Photorhizobium thompsonianum_" <small>Eaglesham _et al_. 1990</small>
- "_B. uaiense_" <small>Cabral Michel _et al_. 2020</small>
- "_B. valentinum_" <small>Durán _et al_. 2014</small>
- "_B. zhanjiangense_" <small>Li _et al_. 2019</small>