Variovorax

Variovorax is a gram-negative bacterial genus from the family Comamonadaceae. Its designated species is Variovorax paradoxus which arose from the species Alcaligenes paradoxus being grouped under the Variovorax genus. The cell size of Variovorax is 0.5–0.6 μm × 1.2–3.0 μm and the optimal growth temperature is 30 degrees Celsius. The bacteria utilise various organic compounds as a carbon source, including fructose, galactose, and glucose, in order to promote plant growth.

Variovorax
Scientific classification
Domain:	Bacteria
Phylum:	Pseudomonadota
Class:	Betaproteobacteria
Order:	Burkholderiales
Family:	Comamonadaceae
Genus:	Variovorax Willems et al. 1991
Type species
Variovorax paradoxus
Species
V. boronicumulans V. defluvii V. dokdonensis V. ginsengisoli V. gossypii V. guangxiensis V. humicola V. paradoxus V. soli

Surface activities in Variovorax paradoxus

Characteristics

Variovorax cells function alone or in pairs, and use a flagellum to move around.They contain carotenoid pigments which leads to a yellow appearance of the colonies. The bacteria are tolerate to a wide variety of metals including cobalt, copper, and nickel, which allows for the bacteria to survive in many environments.

Habitat and occurrence

Bacteria of the Variovorax genus can often be found in damp, dark conditions of soil and water. The bacteria can also be found in a variety of diverse habitats, including the rhizosphere, which is a section of soil in close proximity to the root microbiome. Other habitats that have been recognised include glacial settings, soils contaminated with chemicals and plastics, and riverbed sediments.

Environmental function

Variovorax species have many diverse roles in their environmental surroundings, a noticeable one being promoting plant growth. There is a variety of mechanisms by which the bacteria can accomplish this, including the preventing of plant pathogens being produced, reducing the amount of stress a plant undergoes, and also increasing the number of nutrients that are available. Other roles can also be witnessed, including the cycling of various elements across a range of environments including arsenic. It is thought to oxidise As (III) to As (V) via a detoxification mechanism.

Another potential use which has been discovered for the Variovorax genus is its role in bioremediation studies. Variovorax paradoxus has been found to be a potential use in the bioremediation of soils contaminated with linuron, which could be depolluted through biopurification via bioaugmentation.