Sphingomonadaceae are a

gram-negative bacteria Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ...

l family of the

Alphaproteobacteria Alphaproteobacteria is a class of bacteria in the phylum Pseudomonadota (formerly Proteobacteria). The Magnetococcales and Mariprofundales are considered basal or sister to the Alphaproteobacteria. The Alphaproteobacteria are highly diverse and ...

. An important feature is the presence of

sphingolipids Sphingolipids are a class of lipids containing a backbone of sphingoid bases, a set of aliphatic amino alcohols that includes sphingosine. They were discovered in brain extracts in the 1870s and were named after the mythological sphinx because o ...

(mainly 2′-hydroxymyristol dihydrosphingosine 1-glucuronic acid, "SGL-1") in the outer membrane of the cell wall. The cells are ovoid or rod-shaped. Others are also pleomorphic, i.e. the cells change the shape over time. Some species from Sphingomonadaceae family are dominant components of biofilms.

Energy source

While most species within Sphingomonadaceae family are heterotrophic, some are

phototroph Phototrophs () are organisms that carry out photon capture to produce complex organic compounds (e.g. carbohydrates) and acquire energy. They use the energy from light to carry out various cellular metabolic processes. It is a common misconce ...

ic.

Function

Some species of Sphingomonadaceae are known to degrade some

aromatic compounds Aromatic compounds, also known as "mono- and polycyclic aromatic hydrocarbons", are organic compounds containing one or more aromatic rings. The parent member of aromatic compounds is benzene. The word "aromatic" originates from the past grouping ...

. This makes the bacteria of interest to

environmental remediation Environmental remediation deals with the removal of pollution or contaminants from environmental media such as soil, groundwater, sediment, or surface water. Remedial action is generally subject to an array of regulatory requirements, and may ...

. The diverse metabolic capacity of genera within the ''Sphingomonadaceae'' family, such as '' Sphingobium'', '' Novosphingobium'', and '' Sphingopyxis'' enable these genera to adapt to and be abundant in the presence of

Bisphenol A Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. It is a colourless solid which is soluble in most common organic solvents, but has very poor solubility in water. BPA is produced on an industrial ...

. A microbial community with abundant ''Sphingomonadaceae'' members can degrade

with a constant rate. Some ''

Sphingomonas ''Sphingomonas'' was defined in 1990 as a group of Gram-negative, rod-shaped, chemoheterotrophic, strictly aerobic bacteria. They possess ubiquinone 10 as their major respiratory quinone, contain glycosphingolipids (GSLs), specifically ceram ...

'' species are able to produce sphingans, a kind of exopolysaccharides with certain

viscosity The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the inte ...

. This property of sphingans makes it useful in many industries including food and pharmaceutical.

Distribution

Bacteria within ''Sphingomonadaceae'' family are distributed in various environments, such as water, soil, sediment.

Phylogeny

The currently accepted taxonomy is based on the

List of Prokaryotic names with Standing in Nomenclature List of Prokaryotic names with Standing in Nomenclature (LPSN) is an online database that maintains information on the naming and taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical ...

and the phylogeny is based on whole-genome sequences.

Interaction with human and plants

Some members of the ''Sphingomonadaceae'' commonly exist in human-impacted environments, including drinking water systems, hospital and household tap water, and medical devices. Most of the species of the ''Sphingomonadaceae'' are not known to be harmful to humans or plants. Some species can protect plants from disease-causing pathogens such as '' Thielaviopsis basicola'', and ''

Rhizoctonia solani ''Rhizoctonia solani'' is a species of fungus in the order Cantharellales. Basidiocarps (fruit bodies) are thin, effused, and web-like, but the fungus is more typically encountered in its anamorphic state, as hyphae and sclerotia. The name ''R ...

''. The ''

'' and '' Sphingobium'' genera tend to have higher

antibiotic resistance Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistanc ...

compared with three other genera within the ''Sphingomonadaceae'': '' Novosphingobium'', '' Sphingopyxis'', and '' Blastomonas''.

Notes

References

{{Taxonbar, from=Q577057 Sphingomonadales Bacteria families