Marisia - Maros Megyei Múzeum Évkönyve 32-34. (2014)
Zoology
Mädälin ENACHE, Rázván FIÚMON range of sodium chloride from 2 to 5.2 M, with an optimum in the 2-4 M range. Also, it grew on media supplemented with magnesium chloride, within 0-1 M range, optimum growth being recorded at 0.7-0.8 M magnesium chloride in the presence of 2 M sodium chloride. The investigated strain was sensitive to sodium deoxycholate, and showed resistance to chloramphenicol, novobiocin, bacitracin, eritrhromicin, penicillin, ampicilin and neomycin. Consequently, the investigated strain should be considered as archaea. The new isolate grew optimally at 38°C and pH 7.5, in the presence of 50 mM PIPES (Piperazine-N,N’-bis[2-ethanesulfonicacid]) orHEPES (N—2-N-Hydroxyethylpiperazine-N’—2- ethanesulfonic acid). When tested for catalase and oxidase activities, the novel strain showed positive answer in both cases. Indole from tryptophan and H2S from sodium thiosulphate transformation tests were also positive (Fig. 1). The strain showed no capacity for anaerobic growth in the presence of nitrate, nitrate to nitrite reduction did not occur, and the test for gas producing from nitrite was negative. The extracellular enzymatic spectrum was not represented by amylase, protease (casein and gelatin) or lipase (Table 1). However, the ability of the investigated strain to degrade other substrates cannot be excluded. (a) (b) (c) (d) Fig. 1 - Biochemical properties of RF1. The positive results of catalase test (a), indole production from tryptophan (b), H2S production from sodium thyosulphate (c), and oxidase test (d). All tests are detailed in Materials and methods section. l6S-rDNA sequence of RF1 revealed a high similarity percentage with other members of genus Haloferax. BLAST analysis showed 99% identity with Hfic. alexandrinus, Hfic. lucentense, Hf. sulfurifontis, Hfic. chudinovii, Hfic. volcanii and Hfix. prahovense. Membrane lipid profile investigation indicated the presence of phosphatidyl glycerol phosphate methyl ester (PGP-Me), phosphatidyl glycerol (PG) and phosphatidic acid (PA) as phospholipids. The glycolipid analysis highlighted the presence of diglycosyl archaeol and its sulfated derivative (DGD—1 and S-DGD-1). Based on these data corroborated with the biochemical properties (Table 1), the investigated strain RF1 appears to be a member of the Haloferax genus. Conclusions The RF1 strain is a Gram negative rod that lyses in distilled water and culture medium in the absence of sodium chloride. The colonie are circlular, red-orange, with smooth and elevated surface, and right margins. This halophile is able to grow in the presence of 2 to 5.2 M (with optimum range of 2-4 M) sodium chloride. When cultivated in 2 M NaCl this strain is capable 114
