sphingomonadaceae sphingomonadaceae sphingomonadaceae are a gram-negative bacterial family of the alphaproteobacteria. an important feature is the presence of sphingolipids (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. sphingomonadaceae a culture of sphingomonas phyllosphaerae scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: sphingomonadales family: sphingomonadaceaekosako et al. 2000 type genus sphingomonasyabuuchi et al. 1990 genera aestuariisphingobium li et al. 2020 allosphingosinicella hördt et al. 2020 aquisediminimonas jin et al. 2019 "binariimonas" zhao et al. 2016 blastomonas sly and cahill 1997 chakrabartia jani et al. 2019 "citromicrobium" yurkov et al. 1999 "hankyongella" siddiqi and im 2020 hephaestia felföldi et al. 2014 "lutibacterium" chung and king 2001 novosphingopyxis feng et al. 2020 parablastomonas ren et al. 2015 parasphingopyxis uchida et al. 2012 parasphingorhabdus feng et al. 2020 rhizorhabdus francis et al. 2014 rhizorhapis francis et al. 2014 sphingobium takeuchi et al. 2001 sphingomicrobium kämpfer et al. 2012 sphingomonas yabuuchi et al. 1990 sphingopyxis takeuchi et al. 2001 sphingorhabdus jogler et al. 2013 sphingosinithalassobacter hetharua et al. 2019 stakelama chen et al. 2010 "tardibacter" lee et al. 2018 energy source while most species within sphingomonadaceae family are heterotrophic, some are phototrophic. function some species of sphingomonadaceae are known to degrade some aromatic compounds. this makes the bacteria of interest to environmental remediation. 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. a microbial community with abundant sphingomonadaceae members can degrade bisphenol a with a constant rate. some sphingomonas species are able to produce sphingans, a kind of exopolysaccharides with certain viscosity. 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 and the phylogeny is based on whole-genome sequences. sphingomonadaceae sphingomicrobium sphingopyxis sphingorhabdus parasphingopyxis novosphingopyxis blastomonas parasphingorhabdus rhizorhapis sphingobium stakelama hephaestia sphingomonas allosphingosinicella rhizorhabdus outgroup erythrobacteraceae 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. the sphingomonas and sphingobium genera tend to have higher antibiotic resistance compared with three other genera within the sphingomonadaceae: novosphingobium, sphingopyxis, and blastomonas. notes aestuariisphingobium, aquisediminimonas, chakrabartia, parablastomonas, and sphingosinithalassobacter are not included in this phylogenetic tree.