RT Journal Article SR Electronic(1) A1 Yamauchi, Yuto A1 Minegishi, Hiroaki A1 Echigo, Akinobu A1 Shimane, Yasuhiro A1 Kamekura, Masahiro A1 Itoh, Takashi A1 Ohkuma, Moriya A1 Doukyu, Noriyuki A1 Inoue, Akira A1 Usami, RonYR 2013 T1 Halarchaeumrubridurum sp. nov., a moderately acidophilic haloarchaeon isolated from commercial sea salt samples JF International Journal of Systematic and Evolutionary Microbiology, VO 63 IS Pt_9 SP 3143 OP 3147 DO https://doi.org/10.1099/ijs.0.049262-0 PB Microbiology Society, SN 1466-5034, AB Six halo-acidophilic archaeal strains were isolated from four commercial salt samples obtained from seawater in the Philippines, Indonesia (Bali) and Japan (Okinawa) on agar plates at pH 4.5. Cells of the six strains were pleomorphic, and stained Gram-negative. Two strains were pink–red pigmented, while four other strains were orange–pink pigmented. Strain MH1-16-3T was able to grow at 9–30 % (w/v) NaCl [with optimum at 18 % (w/v) NaCl], at pH 4.5–6.8 (optimum, pH 5.5) and at 20–50 °C (optimum, 42 °C). The five other strains grew at slightly different ranges. The six strains required at least 1 mM Mg2+ for growth. The 16S rRNA gene sequences of the six strains were almost identical, sharing 99.9 (1–2 nt differences) to 100 % similarity. The closest relatives were Halarchaeum acidiphilum MH1-52-1T and Halarchaeum salinum MH1-34-1T with 97.7 % similarity. The DNA G+C contents of the six strains were 63.2–63.7 mol%. Levels of DNA–DNA relatedness amongst the six strains were 79–86 %, while those between MH1-16-3T and H. acidiphilum MH1-52-1T and H. salinum MH1-34-1T were both 43 and 45 % (reciprocally), respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the six isolates represent a novel species of the genus Halarchaeum , for which the name Halarchaeum rubridurum sp. nov. is proposed. The type strain is MH1-16-3T ( = JCM 16108T = CECT 7535T)., UL https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.049262-0