Discovery of Natural Photosynthesis using Zn-Containing Bacteriochlorophyll in an Aerobic Bacterium Acidiphilium rubrum

Abstract

We discovered natural photosynthesis using Zn-containing bacteriochlorophyll α in an acidophilic bacterium Acidiphilium rubrum. Chemical analysis of the cell extracts gave a 13 : 2 :1 molar ratio of Zn-bacteriochlorophyll α : Mg-bacteriochlorophyll α : bacteriopheophytin α. Most of the pigments are associated with fully active reaction center and light-harvesting complexes analogous to those in purple photosynthetic bacteria. The finding indicates an unexpectedly wide variability of photosynthesis.