Sphingopyxis italica sp. nov., isolated from Roman catacombs

Abstract

A Gram-stain-negative, aerobic, motile, rod-shaped bacterium, strain SC13E-S71T, was isolated from tuff, volcanic rock, where the Roman catacombs of Saint Callixtus in Rome, Italy, was excavated. Analysis of 16S rRNA gene sequences revealed that strain SC13E-S71T belongs to the genus Sphingopyxis , and that it shows the greatest sequence similarity with Sphingopyxis chilensis DSM 14889T (98.72 %), Sphingopyxis taejonensis DSM 15583T (98.65 %), Sphingopyxis ginsengisoli LMG 23390T (98.16 %), Sphingopyxis panaciterrae KCTC 12580T (98.09 %), Sphingopyxis alaskensis DSM 13593T (98.09 %), Sphingopyxis witflariensis DSM 14551T (98.09 %), Sphingopyxis bauzanensis DSM 22271T (98.02 %), Sphingopyxis granuli KCTC 12209T (97.73 %), Sphingopyxis macrogoltabida KACC 10927T (97.49 %), Sphingopyxis ummariensis DSM 24316T (97.37 %) and Sphingopyxis panaciterrulae KCTC 22112T (97.09 %). The predominant fatty acids were C18 : 1ω7c, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), C14 : 0 2-OH and C16 : 0. The predominant menaquinone was MK-10. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and sphingoglycolipid. These chemotaxonomic data are common to members of the genus Sphingopyxis . However, a polyphasic approach using physiological tests, DNA base ratios, DNA–DNA hybridization and 16S rRNA gene sequence comparisons showed that the isolate SC13E-S71T belongs to a novel species within the genus Sphingopyxis , for which the name Sphingopyxis italica sp. nov. is proposed. The type strain is SC13E-S71T ( = DSM 25229T = CECT 8016T).