Photosystem I and Photosystem II were separated from a type of bacteria called Prochlorothrix hollandica. This separation was done by using a special detergent and a technique called sucrose gradient centrifugation. The researchers found that the chlorophyll a/b antennae, which help capture light for photosynthesis, are located near Photosystem II. These antennae contain specific proteins and have a higher ratio of chlorophyll a to chlorophyll b compared to other plants. Interestingly, Photosystem I in this bacteria does not have its own chlorophyll b-containing antenna like other plants do.