Before Thiocystis divides into typical diplococci, the cells are spherical to ovoid, reproduction in a dichotomy, and move with polar flagella. In certain unfavorable conditions and many natural environments, cells do not move and form almost regular aggregates covered by mucus. Thiocystis belongs to Gram-negative bacteria. The bacteria have chlorophyll a and carotenoids, both of which are located on the inner membrane of the sac type. There are no air bubbles in the bacteria.
Figure 1. The image shows a microscopic image of a thiocystis species. (Form vietsciences.free.fr)
Thiocystis belongs to anaerobic bacteria. When there is hydrogen sulfide, it can carry out photosynthesis, and at the same time produce sulfur (as an intermediate metabolic oxidation product) and store it in the cell in a spherical shape. Molecular hydrogen in the bacteria can be used as an electron donor. During photosynthesis, molecular oxygen is not released. The cell suspension is brown to purple-red and violet in different shades due to photosynthetic pigments.
Thiocystis violacea
The cell diameter of Thiocystis violacea is about 2.5-3 microns; larger single cells can appear due to environmental influences. Under unfavorable conditions, irregular cell aggregates enclosed by mucocapsules are formed. Sulfur balls are evenly distributed throughout the cell.
Thiocystis violacea belongs to obligate photoautotrophic bacteria and is anaerobic. pH range: 4.3-8.0; optimal pH, 7.0-7.5. Growth temperature: 25°-30°C.
Thiocystis gelatinosa
The spherical cell diameter of Thiocystis gelatinosa is about 3 microns; under unfavorable conditions, prolonged oval cells appear due to the delay of cell division. Under strong luminosity, high concentration of sulfide and bad conditions, the cells do not move and form irregular aggregates encased in mucus. Elemental sulfur balls only appear around the cytoplasm. The individual cells are pale pink, while the cell suspension is purple-red.
Thiocystis gelatinosa is an obligate autotrophic, strictly anaerobe. pH range: 6.5-7.6. Optimal growth temperature: 25°-30℃. The new model strain requires 1% sodium chloride.
The culture of Thiocystis requires specific formulations of growth media for use in cloning, plasmid DNA preparation, and protein expression. Creative Biogene offers a selection of bacterial growth media and custom services for your specific application. If you are interested in our microbial anaerobic and aerobic culture platform, please contact us for more details.
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