Edit photosynthetic bacteria entry
Photosynthetic bacteria (PSB) is the earliest prokaryote on the earth, which is ubiquitous in nature and has a primitive light energy synthesis system. It is the general name of bacteria that carry out anaerobic photosynthesis under anaerobic conditions. It is a Gram-negative bacterium which has no ability to form spores, and it has a certain color because of its photosynthetic pigments such as bacterial chlorophyll and carotenoids. PSB bacteria widely exist in the earth's biosphere. In aquaculture, it can degrade toxic substances such as nitrite and sulfide in water, so as to serve as bait, purify water, prevent diseases and serve as feed additives. Photosynthetic bacteria have strong adaptability, can tolerate high-depth organic wastewater and have strong decomposition and transformation ability, and have certain tolerance and decomposition ability to phenols, cyanide and other poisons. Its many characteristics make it have great application value in pollution-free aquaculture.
Biological characteristics of photosynthetic bacteria
Photosynthetic bacteria are widely distributed in natural soil, paddy fields, swamps, lakes, rivers and oceans. , mainly distributed in the anoxic area with light transmission in aquatic environment. The optimum water temperature of photosynthetic bacteria is 15-400℃, and the optimum water temperature is 28-360℃. PSB is rich in nutrients, and the cell dry matter contains more than 65% protein. The amino acid composition of protein is relatively complete. Cells also contain a variety of vitamins, especially B vitamins, Vb2, folic acid, pantothenic acid and biotin, as well as a large number of carotenoids, coenzyme Q and other physiologically active substances. Therefore, photosynthetic bacteria have high nutritional value, which is the material basis for their use as hydroponic bait and feed additive in aquaculture.
Photosynthetic bacteria can carry out photosynthesis in the environment with light and hypoxia, use light energy to carry out photosynthesis, and use light energy to assimilate carbon dioxide. Unlike green plants, their photosynthesis does not produce oxygen. There is only one photosystem PSI in photosynthetic bacteria cells. The initial hydrogen donor for photosynthesis is H2S (or some organic matter), not water. As a result of photosynthesis, it produces H2, decomposes organic matter, and fixes molecular nitrogen in the air to produce ammonia. In the process of its own assimilation and metabolism, photosynthetic bacteria have completed three extremely important chemical processes in the natural material cycle: hydrogen production, nitrogen fixation and decomposition of organic matter. These unique physiological characteristics make them extremely important in the ecosystem.
Photosynthetic bacteria used in aquaculture are mainly some species of Rhodosporidae, such as Rhodopseudomonas palustris;
In nature, fresh seawater usually contains nearly 100 PSB bacteria per milliliter. The cells of photosynthetic bacteria use organic acids, amino acids, ammonia, sugars and hydrogen sulfide as oxygen supply, and obtain energy through photosynthetic phosphorylation. Under the illumination of water, they can directly degrade organic matter and hydrogen sulfide and proliferate themselves, thus purifying water.