Halogranum rubrum gen. nov., sp. nov., a halophilic archaeon isolated from a marine solar saltern

Abstract

Two extremely halophilic archaea, strains RO2-11(T) and HO2-1, were isolated from two Chinese marine solar salterns, Rudong solar saltern and Haimen solar saltern, respectively. Cells of the two strains were polymorphic and Gram-stain-negative; colonies were red-pigmented. The two strains grew at NaCl concentrations of 2.6-4.3 M (optimum 3.9 M) and required at least 0.1 M Mg2+ for growth. They were able to grow over a pH range of 6.0-8.0 and a temperature range of 20-50 degrees C, with optimal pH of 7.5 and optimal temperature of 37 degrees C. The major polar lipids of strain RO2-11(T) and strain HO2-1 were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and three glycolipids, two of them chromatographically identical to S-DGD-1 and DGD-1, the third unidentified. The 16S rRNA gene sequence similarity of strain RO2-11(T) and strain HO2-1 was 99.3 % and highest sequence similarity with the closest relative (Haloferax larsenii) was 91.4 %. Based on the data obtained, the two isolates could not be classified in any recognized genus of the family Halobacteriaceae. Strain RO2-11(T) and strain HO2-1 are thus considered to represent a novel species of a new genus within the family Halobacteriaceae, for which the name Halogranum rubrum gen. nov., sp. nov. is proposed. The type strain is RO2-11(T) (=CGMCC 1.7738(T) =JCM 15772(T)).

Insights into the metabolism, lifestyle and putative evolutionary history of the novel archaeal phylum ‘Diapherotrites’

“…Historically, Archaea were regarded as a collection of extremophiles that could only thrive in extreme habitats, for example, high temperature (Huber et al, 1991;Jannasch et al, 1992;Antoine et al, 1995;Whitaker et al, 2003), high salinity (Oren et al, 1990;Cui et al, 2010;Goh et al, 2011;Inoue et al, 2011), low pH (Edwards et al, 2000;Dopson et al, 2004), strict anaerobic conditions (Mikucki et al, 2003;Sakai et al, 2007) or combinations thereof (Huber et al, 1989;Itoh et al, 1999;Minegishi et al, 2008Minegishi et al, , 2013.…”

Halobium palmae gen. nov., sp. nov., an extremely halophilic archaeon isolated from a solar saltern

“…T and related genera in the family Halorubraceae Taxa: 1, strain 2a_47_2 T (data from this study); 2, Halorubrum (Oren, 2014;Corral et al, 2016); 3, Halopenitus (Amoozegar et al, , 2013Han & Cui, 2014); 4, Halobaculum (Oren et al, 1995;Shimosige et al, 2013); 5, Halohasta (Mou et al, 2012); 6, Halolamina (Koh et al, 2015); 7, Halonotius (Burns et al 2010); 8, Salinigranum (Cui & Zhang, 2014); 9, Halogranum (Cui et al, 2010(Cui et al, , 2011Kim et al, 2011). +, Positive; À, negative; ND, not determined.…”

Halogranum gelatinilyticum sp. nov. and Halogranum amylolyticum sp. nov., isolated from a marine solar saltern, and emended description of the genus Halogranum

“…Characteristics that distinguish strains TNN44 T and TNN58 T from Halogranum rubrum RO2-11 T are shown in Table 1. Cui et al 2010 Cells are pleomorphic under optimal growth conditions and stain Gram-negative. Aerobic heterotrophs.…”

“…Among these halophilic micro-organisms, halophilic archaea are probably the dominant microbes at saltern crystallizer ponds (Oren, 2002). To understand better the biogeographical distribution and diversity of halophilic archaeal communities within different marine solar salterns along the coastline of eastern China (Cui et al, 2010), brine and sediment samples were collected from Tainan marine solar saltern (34 u 359 380 N 119 u 289 560 E) near Lianyungang city, Jiangsu province, and their halophilic archaeal diversity was examined based on analysis of a library of PCR-amplified 16S rRNA genes and by cultivation. Of 65 isolates examined, one strain showed 99.9 % 16S rRNA gene sequence similarity to the type strain of Salinibacter ruber (Antó n et al, 2002); the other 64 strains belonged to the family Halobacteriaceae.…”