Sphingomonas solaris sp. nov., isolated from a solar panel in Boston, Massachusetts

Abstract

Solar panel surfaces, although subjected to a range of extreme environmental conditions, are inhabited by a diverse microbial community adapted to solar radiation, desiccation and temperature fluctuations. This is the first time a new bacterial species has been isolated from this environment. Strain R4DWNT belongs to the genus Sphingomonas and was isolated from a solar panel surface in Boston, MA, USA. Strain R4DWNT is a Gram-negative, non-motile and rod-shaped bacteria that tested positive for oxidase and catalase and forms round-shaped, shiny and orange-coloured colonies. It is mesophilic, neutrophilic and non-halophilic, and presents a more stenotrophic metabolism than its closest neighbours. The major fatty acids in this strain are C18:1ω7c/C18:1ω6c, C16:1ω7c/C16:1ω6c, C14:0 2OH and C16:0. Comparison of 16S rRNA gene sequences revealed that the closest type strains to R4DWNT are Sphingomonas fennica , Sphingomonas formosensis , Sphingomonas prati , Sphingomonas montana and Sphingomonas oleivorans with 96.3, 96.1, 96.0, 95.9 and 95.7 % pairwise similarity, respectively. The genomic G+C content of R4DWNT is 67.9 mol%. Based on these characteristics, strain R4DWNT represents a novel species of the genus Sphingomonas for which the name Sphingomonas solaris sp. nov. is proposed with the type strain R4DWNT (=CECT 9811T=LMG 31344T).