Donald A. Bryant (March 12, 1950 â August 28, 2024) was an American bioscientist. He was the Ernest Pollard Chair of Biotechnology at the Eberly College of Science Pennsylvania State University. He published numerous research publications which are widely cited. Bryant's significant contributions include elucidating the key mechanisms of bacterial photosynthesis and the physiology of chlorophototrophic microbes. His pioneering work provided deep insights into microbial light-harvesting systems and their ecological significance.
Bryant's research focused on understanding photosynthesis in two distinct groups of bacteria. Cyanobacteria produce oxygen as a photosynthetic byproduct. In contrast, he also researched green sulfur bacteria which are anaerobic and can survive only in the absence of oxygen.
Bryant authored the book, The Molecular Biology of Cyanobacteria (1994) which summarizes and analyzes the taxonomy, biochemistry, physiology, cellular differentiation and developmental biology of cyanobacteria, which was relatively understudied at the time.