Halobacterium has a photosynthetic membrane that appears purple. its photosynthetic action spectrum is the inverse of the action spectrum for green plants. (that is, the halobacterium action spectrum has a peak where the green plant action spectrum has a trough.) what wavelengths of light do the halobacterium photosynthetic pigments absorb?

Yellow - Green Wavelength of light at peak absorption of 565nm.

Halobacterium is known to be a member of Archaea and they thrive in very salty environment such as Great Salt lake and Dead Sea. Halobacteria under the process of photosynthesis with chlorophyll and they make their ATP from the sunlight using bacteriorhodopsin and halorhodopsin as photosynthetic pigments.

However, photosensory pigements found in Halabacterium were:

1. photosystem 565 which is used to respond to yellow - green light in other for cell to find optimum conditions for ATP synthesis and photophosphorylation and they have peak absorbtion at 565nm.

2. Photosystem 370 nm appears to be responsible for the protective avoidance of blue/UV light.