Imperialibacter roseus gen. nov., sp. nov., a novel bacterium of the family Flammeovirgaceae isolated from Permian groundwater Hui Wang, 1,2,3 Junde Li, 1 Tianling Zheng, 2 Russell T. Hill 3 and Xiaoke Hu 1 Correspondence Xiaoke Hu xkhu@yic.ac.cn 1 Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China 2 Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361005, China 3 Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD 21202, USA A novel bacterial strain, designated P4 T , was isolated from Permian groundwater and identified on the basis of its phylogenetic, genotypic, chemotaxonomic and phenotypic characteristics. Cells were aerobic, Gram-stain-negative rods. 16S rRNA gene sequence-based phylogenetic analysis revealed that P4 T is affiliated with the family Flammeovirgaceae in the phylum Bacteroidetes, but forms a distinct cluster within this family. The DNA G+C content of strain P4 T was 45.2 mol%. The predominant cellular fatty acids were C 16 : 1 v6c/C 16 : 1 v7c and iso-C 15 : 0 . MK-7 was the main respiratory quinone. The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, unidentified phospholipids, an unidentified aminolipid, unidentified glycoli- pids and unidentified polar lipids. Based on our extensive polyphasic analysis, a novel species in a new genus, Imperialibacter roseus gen. nov., sp. nov., is proposed. The type strain of Imperialibacter roseus is P4 T (5CICC 10659 T 5KCTC 32399 T ). Bacteria affiliated with the family Flammeovirgaceae of the phylum Bacteroidetes are widely distributed in various environments, particularly in aquatic systems. Detailed study has led to the identification of a number of new genera in the family Flammeovirgaceae in recent years (Khan et al., 2007; Nedashkovskaya et al., 2007; Seo et al., 2009; Srisukchayakul et al., 2007; Yoon et al., 2007, 2008, 2011). A bacterial strain, designated P4 T , was isolated from Permian groundwater as part of a study to use this novel water source for cultivation of biofuel-producing microalgae (Wang et al., 2012). Polyphasic taxonomic tests including phylogenetic, genotypic, chemotaxonomic and phenotypic assays were performed in order to identify the novel strain described here. The bacterial strain P4 T belongs to a novel genus and species in the family Flammeovirgaceae. Permian groundwater used for isolation of bacteria was collected from the Pecos Cenozoic Trough in Imperial, TX, USA (31 u 169 16.930 N 102 u 409 48.350 W). Strain P4 T was successfully isolated on Difco marine agar 2216 plates (BD Bioscience) at 30 u C and cryo-preserved at 280 u C in marine broth 2216 supplemented with 30 % (v/v) glycerol. After 48 h of incubation on marine agar plates, the aerobic bacterium formed circular, flat, pink colonies. Gram staining was performed according to the method described by Gerhardt et al. (1994). Scanning electron microscopy was applied to observe the morphology of strain P4 T . The results indicate that strain P4 T is a Gram-stain-negative, rod-shaped bacterium (Fig. 1). Genomic DNA was extracted using an Ultra-Clean microbial DNA isolation kit (MoBio Laboratories). PCR amplification and 16S rRNA gene sequencing were performed as described previously (Enticknap et al., 2006). The almost full-length 16S rRNA gene was analysed using the EzTaxon server 2.1 (Chun et al., 2007). The 16S rRNA gene sequence of strain P4 T was aligned with those of representative members of selected genera belonging to the families Cyclobacteriaceae and Flammeovirgaceae in the phylum Bacteroidetes. Phylogenetic analysis was conducted using the MEGA 4 software package (Tamura et al., 2007). A phylogenetic tree was reconstructed using the neighbour- joining algorithm (with Jukes–Cantor correction). The robustness of the inferred tree topology was evaluated after 1000 bootstrap replicates of the neighbour-joining data. The taxonomic analysis using EzTaxon showed that the 16S rRNA gene sequence of strain P4 T was no more than 88 % similar to that of any previously identified type strain. The closest cultured strains, Algoriphagus halophilus JC 2051 T (88.18 %) and Fulvivirga kasyanovii KMM 6220 T (88.16 %), were affiliated with different families, Cyclobacteriaceae and The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain P4 T is KC800928. A supplementary table is available with the online version of this paper. International Journal of Systematic and Evolutionary Microbiology (2013), 63, 4136–4140 DOI 10.1099/ijs.0.052662-0 4136 052662 G 2013 IUMS Printed in Great Britain