Study On Halobacteria

Master degree dissertation Study on Halobacteria(Collelge of Life Science, Northwest University, China)Xu Jin-gui (Microbiology)Directed by Guo Ai-lianSome biochemical characters and optical culture condition of two strains Halobacterium halobium B and S9 were mainly studied in this thesis.The two strains were all Gram-negative-bacteria. The color of colony in milk - salt - agar medium was red. The size of B was 0.69 -0.96 x 2.76 - 4.1 um, and S9 was 0.97 - 1.10 x 3.9 - 4.2 urn. The best concentration of NaCl was 20%, and temperature was 38癈. Both strains contained bacterioruberin.The culture, separation and purification of purple membrane were tested in this thesis.The results screening and optimizing by Plackett-Burman Design and orthogonal test accorded with the results optimizing by the single factor test. The best results as following:Culture medium of B (g/L): MgSO4-7H2O 20, Casamino acid 5, NaCl 200, Yeast extraction 10, trisodium citrate 2.25, FeSO4-7H2O 0.05, KC1 2.5, glycerol 10, pH 6.5. The culture volume was from 1/4 to 1/3 of the conical flask volume, and shaking speed was 180 rpm with illumination.Culture medium of S9 (g/L): MgSO4-7H2O 25, Casamino acid 10, NaCl 200, Yeast Extraction 5, trisodium citrate 2.25, FeSO4-7H2O 0.1, KC1 2.5, glycerol 10, pH 7.0. The culture volume was from 1/4 to 1/3 of the conical flask volume, and shaking speed was 180 rpm with illumination.