Question

75. The extreme halophiles form another archaeal group that is easily characterized due to their unusual habitat requirements. Where could you go to collect some extreme halophiles from the wild? The pigments of halophiles allow them to absorb light as a source of energy, but how is what they do different from what we normally think of as photosynthesis (as occurring with a plant or a cyanobacterium)?

Answer 1

Halophiles are the organism which can grow in high salt concentration. Further, extreme halophiles organisms have unusual habitual requirements. Salinibacter ruber, Hortaea werneckii and halobactria are the few example of the extreme halophiles. Extreme halophile organism can survive in 2M salt concentration or upto 35% (v/v) salt water. It can be found in Salt Lake, sea water where minimum salt concentration is 35% (v/v), evaporation pond used for salt formation etc. Great salt lake, Dead sea are few place where you can find extreme halophiles organism.

On the other hand, extreme halophiles have limitation of oxygen due to high salt concentration. In plant and algae sunlight used for photosynthesis but in halophiles, sunlight is used for other purpose than photosynthesis and that is Photophosphorylation. Photophosphorylation is the process of formation of ATP (energy coin) by using sunlight. In the presence of sunlight, a proton gradient will be generated which ultimately resulted as activation of driving of ATPase which help in synthesis of ATP.