Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of bio...Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of biological functions. Ten red colordes were isolated from brine water in a saltem crystaltizer pond of the Hangu Saltworks, China. 16S rRNA gene sequence analysis showed that the colonies belonged to the extremely halophilic archaea genera Halobacterium and Halorubrum. Two representative strains, Halobacterium strain SP-2 and Halorubrum strain SP-4, were selected for further study on the phenotypic characteristics and effects of salinity and pH on accumulation and composition of pigments in their cells. The archaeal strains were isolated and grown in a culture medium prepared by dissolving yeast extract （10 g/L） and acid-hydrolyzed casein （7.5 g/L） into brine water obtained from a I.ocal salt pond. Their optimum salinity and pH for growth were 250 and 7, respectively, although pigment accumulation （OD490/ mL broth） was highest at pH 8. In addition, at 150-300 salinity, increasing salinity resulted in decreasing pigment accumulation. Analysis of the UV-Vis spectrum, TLC and HLPC chromatograms showed that C50 carotenoid bacterioruberin is the major pigment in both strains.展开更多
Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2μm,wherein...Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2μm,wherein a few cells are globular.The optimum salt concentration for its growth is 20%NaCl and 0.6%Mg^(2+),and the optimum pH is 6.0–7.0.Morphological,physiological,and biochemical characteristics of strain AJ6 were observed.The 16S rRNA encoding gene(16S rDNA)sequence of strain AJ6 was amplified by PCR,and its nucleotide sequence was determined subsequently.“Clustalw”and“PHYLIP”software bags were used to analyze the 16S rDNA sequence;the homology was compared,and then the phylogenetic tree was established.The results indicate that strain AJ6 is a novel species of the genus Natrinema.The GenBank accession number of the 16S rDNA sequences of strain AJ6 is AY277584.展开更多
基金Supported by the International Cooperation Research Program of the Ministry of Science&Technology of China(No.2010DFA32300)the Natural Science Foundation of Tianjin(No.13JCZDJC28700)
文摘Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of biological functions. Ten red colordes were isolated from brine water in a saltem crystaltizer pond of the Hangu Saltworks, China. 16S rRNA gene sequence analysis showed that the colonies belonged to the extremely halophilic archaea genera Halobacterium and Halorubrum. Two representative strains, Halobacterium strain SP-2 and Halorubrum strain SP-4, were selected for further study on the phenotypic characteristics and effects of salinity and pH on accumulation and composition of pigments in their cells. The archaeal strains were isolated and grown in a culture medium prepared by dissolving yeast extract （10 g/L） and acid-hydrolyzed casein （7.5 g/L） into brine water obtained from a I.ocal salt pond. Their optimum salinity and pH for growth were 250 and 7, respectively, although pigment accumulation （OD490/ mL broth） was highest at pH 8. In addition, at 150-300 salinity, increasing salinity resulted in decreasing pigment accumulation. Analysis of the UV-Vis spectrum, TLC and HLPC chromatograms showed that C50 carotenoid bacterioruberin is the major pigment in both strains.
基金was supported by the National Natural Science Foundation of China (No.30370029).
文摘Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2μm,wherein a few cells are globular.The optimum salt concentration for its growth is 20%NaCl and 0.6%Mg^(2+),and the optimum pH is 6.0–7.0.Morphological,physiological,and biochemical characteristics of strain AJ6 were observed.The 16S rRNA encoding gene(16S rDNA)sequence of strain AJ6 was amplified by PCR,and its nucleotide sequence was determined subsequently.“Clustalw”and“PHYLIP”software bags were used to analyze the 16S rDNA sequence;the homology was compared,and then the phylogenetic tree was established.The results indicate that strain AJ6 is a novel species of the genus Natrinema.The GenBank accession number of the 16S rDNA sequences of strain AJ6 is AY277584.
