Sphingomonas turrisvirgatae sp. nov., an agar-degrading species isolated from freshwater

Abstract

A yellow pigmented and agar-pitting colony was isolated from a water sample obtained from a drainage ditch within a disused system of constructed wetlands. The strain was purified and named MCT13. This rod-shaped, Gram-negative, oxidase- and catalase-positive, aerobic, non-spore-forming, and non-motile strain formed round colonies and grew optimally at pH 7.5±0.2, at 28-30 °C on LB agar, with 0-0.5 % NaCl. The 16S rRNA gene sequence analysis placed the MCT13 isolate within the Sphingomonas (sensu stricto) cluster. The DNA G+C content was 65.3 %. The only observed ubiquinone was Q10. The major fatty acids included C17 : 1ω6c and C18 : 1ω7c/C18 : 1ω6c. The major polar lipids were sphingoglycolipid, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The major polyamine was spermidine. The 16S rRNA gene phylogenetic analysis performed on the whole sequence, showed the closest relative of MCT13 to be Sphingomonas koreensis (98.52 %); however, there are several genotypic and phenotypic differences between the novel isolate and the type strain JSS26 of S. koreensis. On the basis of these results, strain MCT13 represents a novel species in the genus Sphingomonas, for which the name Sphingomonas turrisvirgatae sp. nov. is proposed. The type strain is MCT13 (=DSM 105457=BAC RE RSCIC 7).

Characterization of vB_StuS_MMDA13, a Newly Discovered Bacteriophage Infecting the Agar-Degrading Species Sphingomonas turrisvirgatae

“…The recently described agarolytic species S. turrisvirgatae (type strain MCT13 = DSM 105457 T = BAC RE RSCIC 7 T ), isolated from a drainage ditch within a disused system of constructed wetlands located in Rome [28], was used as host for the isolation and propagation of the vB_StuS_MMDA13 bacteriophage. SM buffer (10 mM Tris-HCl, pH 7.5; 100 mM NaCl; 10 mM MgSO 4 ) was employed for suspending and titrating bacteria and phages.…”

Characterization of Agarolytic Pathway in a Terrestrial Bacterium Cohnella sp. LGH

“…It is interesting that the algal polysaccharide agarose cannot be commonly found in terrestrial environments as there have been increasing reports about agar-degrading bacteria isolated from terrestrial environments in recent years ( Li et al, 2015 ; Pluvinage et al, 2018 ; Thaller et al, 2018 ). We noticed that the increasing production of cultured algae is a phenomenon that cannot be ignored.…”

Sphingomonas suaedae sp. nov., a chitin-degrading strain isolated from rhizosphere soil of Suaeda salsa

“…The tree topology was assessed by the bootstrap resampling method with 1000 replicates [33]. The results of phylogenetic analysis revealed that strain XS-10 T formed a stable clade with Sphingomonas turrisvirgatae MCT13 T (=DSM 105457 T ) [19] and Sphingomonas koreensis JSS-26 T (=JCM 11456 T ) [34], sharing 98.4 and 97.5 % of the 16S rRNA gene similarities to S. koreensis JSS-26 T and S. turrisvirgatae MCT13 T , respectively, still below the 98.7 % threshold for a new species [35] (Fig. 1), suggesting that strain XS-10 T belonged to the genus Sphingomonas.…”

“…+, Positive; −, negative; nd, no data. *Data for the reference strains were compiled from corresponding literatures [1,19,34].…”

“…They were isolated from various habitats, i.e. soil [9,12,18], fresh water [19], as well as part of plants, such as the phyllosphere, rhizosphere and roots [20]. Many Sphingomonas bacteria can utilize or degrade a wide range of natural compounds and environmental contaminants, including orthophenylphenol [21], dioxin [22], naphthalenesulfonic acids [23] and polychlorinated biphenyls [24].…”