Final Report Summary - PHOTOPHAGE (The role of viral photosynthetic proteins in oceanic photosynthesis)
The main purpose of the PhotoPhage project is to learn about viral ‘photosynthesis’ using environmental as well as lab-based experiments. Using samples from around the globe we were able to learn about the huge diversity of the viral PSI genes and to draw their distribution pattern. The viral genes were found in the Pacific, Atlantic and Indian Oceans and were confined to a strip along the equator. In addition we found that the photosynthetic genes on the two different gene clusters are encoding for structurally different proteins. This implies for different mechanistic modes of photosynthesis.
Our wet-lab experiments show that when phages that carry both PSI and PSII genes are infecting cyanobacteria, they express their photosynthetic genes and the viral proteins are entering in the host membranes. The infected cells keep performing photosynthesis during the entire period of infection and enhance cyclic photosynthesis. Thus keep harvesting light energy while infected and probably using this excess energy to produce more phage progeny.