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Adam J. Bogdanove was born in Albany, New York. He earned a B.S. in Biology in 1987 from Yale University and a Ph.D. in Plant Pathology from Cornell University in 1997. Bogdanove conducted postdoctoral studies at Purdue University and the Boyce Thompson Institute for Plant Research. He joined the Department of Plant Pathology at Iowa State University in 2000 as an Assistant Professor where he rose through the ranks to Full Professor. In 2012 he returned to Ithaca as Professor of Plant Pathology and Plant- Microbe Biology in the School of Integrative Plant Science at Cornell University.

Dr. Bogdanove has made fundamental advances in our understanding of bacterial pathogenesis of plants, which have led to novel approaches to disease control and revolutionary tools for biology. His research over the past 15 years has focused on molecular mechanisms involved in the infection of rice by two important pathogens, Xanthomonas oryzae pv. oryzae and X. o. pv. oryzicola. He led a large collaborative effort to fully sequence the genome of a representative strain of each pathogen, helping to establish those strains as experimental models. Dr. Bogdanove made the seminal discovery of a remarkable virulence mechanism that has led to novel technologies for DNA targeting, including making precise changes in eukaryotic genomes.

Early in his career Dr. Bogdanove discovered that X. o. pv. oryzicola depends on type III secretion for pathogenesis and that one of the capabilities of Xanthomonas effectors is suppression of host defenses, a widespread phenomenon underlying the breakdown of crop resistance in the field. He went on to use a transposon mutant screen that revealed roles in virulence for the rpfG/rpfC two-component regulatory system, LPS, and type IV pili. Subsequently, Dr. Bogdanove led an international collaboration to sequence virulent strains of X. o. pv. oryzicola and X. o. pv. oryzae that are, importantly, experimentally tractable. The genome sequences enabled functional genomics in both pathogens, helping to explain the challenges in breeding durable resistance in rice. More recently Dr. Bogdanove has pioneered the use of long-read sequencing technology for moderate throughput Xanthomonas genome sequencing that captures the highly repetitive genes encoding transcription activator-like (TAL) effectors, which are determinative virulence and avirulence factors in many Xanthomonas-plant interactions.

TAL effectors have been studied since the early 1990s, and were known to directly activate specific host genes, but how TAL effectors recognize their targets was unknown. In 2009, Dr. Bogdanove deciphered that mechanism. TAL effectors use tandem, polymorphic amino acid repeats that independently specify single contiguous nucleotides to find and bind specific DNA sequences in the host genome. The resulting landmark publication appeared in Science along with a paper from the laboratory of Jens Boch in Germany. The discovery of how TAL effectors target specific genes to promote disease also explained how some host plants have evolved promoter elements that act as TAL ‘decoys’ to cause expression of ‘executor’ genes leading to disease resistance. These papers inaugurated a new era in Xanthomonas biology with far-reaching ramifications for disease control and showed that TAL effectors could be customized to bind sequences of choice, revolutionizing the field of DNA targeting.

Dr. Bogdanove has continued to make important discoveries in TAL effector biology. His collaboration with Barry Stoddard at the Fred Hutchinson Cancer Research Center revealed that each TAL effector repeat forms a two-helix bundle that presents a base-specifying residue to the DNA, with the repeats self-associating to form a superhelix wrapped around the DNA major groove. This structure reveals the basis for TAL effector-DNA recognition and provides a foundation for more efficient exploitation of TAL effectors.

With direct implications for disease control, Dr. Bogdanove’s laboratory demonstrated that the promoter of a rice gene for bacterial blight resistance bound by a TAL effector found in some strains of X. o. pv. oryzae could be amended with additional TAL effector binding sites to provide resistance to several strains of X. o. pv. oryzae and all tested strains of X. o. pv. oryzicola. In related work, Dr. Bogdanove and his collaborators are using tools such as machine learning and transcriptomics to identify new targets important for disease development, yielding insights with additional potential for disease control.

A broadly consequential aspect of Dr. Bogdanove’s research is the application of TAL effector biology to DNA targeting, most notably precise editing of eukaryotic genomes. Together with Daniel Voytas at the University of Minnesota, Bogdanove developed the first TAL effector endonucleases (TALENs) for making targeted double strand DNA breaks in living cells, a key step in genome editing. Characterized by their high specificity and straightforward targetability, TALENs have propelled the genome editing revolution, driving advances in agriculture, medicine, and fundamental research. The impact of this work has been enhanced by Dr. Bogdanove’s development and sharing of tools for TAL effector-based applications, including web-based design and target prediction software and a complete plasmid kit enabling rapid assembly of custom TAL effector constructs. In 2014 alone, the web-based software processed 24,511 tasks for 2,989 unique users, and to date over 1,500 requests have been filled for the kit.

Dr. Bogdanove continues to provide leadership in understanding the roles of TAL effectors and their targets in plant disease and in using genome editing to advance plant biology. He is the PI on a recently funded collaborative NSF project on 'QTL Engineering', part of which will offer a workshop to junior scientists on genome editing methods. Dr. Bogdanove’s accomplishments are increasingly being recognized and he was recently announced as the 2015 recipient of the Cornell University College of Agriculture and Life Sciences Award for Outstanding Accomplishments in Research.

Based on his distinguished contributions to our understanding of the Xanthomonas-rice interaction which have the potential for profound impact on controlling two important diseases of rice and his development of genome-editing methods inspired by molecular plant pathology, Professor Adam J. Bogdanove is well-deserving of the Noel T. Keen Award for Research Excellence in Molecular Plant Pathology.