Alan Collmer was born in 1945 in Philadelphia. He received a B.A. degree from Antioch College (1973) and a Ph.D. degree from Cornell University (1981). He was a postdoctoral associate in the laboratory of D. Wilson at Cornell (1981–1982) before accepting a faculty position in the Department of Botany at the University of Maryland, where he was promoted to associate professor in 1987. He joined the Department of Plant Pathology at Cornell in 1988 and became a full professor in 1994.
Dr. Collmer has made major contributions to the teaching of plant pathology and is widely recognized for his research program, both among plant pathologists and in the wider community of microbiologists. His laboratory has consistently made fundamental discoveries that have changed our view of microbiological processes and molecular mechanisms of bacteria pathogenic to plants. He determined the relative role of pectate lyase (PL) isozymes in Erwinia chrysanthemi soft rot disease by deleting from the bacterial genome the genes encoding PL. In the process, he discovered an unknown set of enzymes produced by the bacterium primarily in the plant. His laboratory contributed to the demonstration that the type II protein secretion pathway is widely found in gram-negative bacteria, including plant pathogens. He also discovered that type II pathways are species-specific (i.e., any particular species can secrete its own PL but not that of any other species) and determined the source of the specificity: for at least one pair of PL proteins, the C-terminal regions appear to be recognized by two species-specific secretory proteins. Dr. Collmer was instrumental in the discovery of a totally new bacterial secretory pathway (type III), encoded by a 25-kb cluster of hrp genes in Pseudomonas synringae. This pathway secretes, the recently discovered harpins, proteins contributing to induction of the hypersensitive response (HR) in incompatible plants and pathogenicity in compatible plants. The most remarkable outcome of these investigations was the discovery that the type III pathway is conserved in bacterial pathogens of both plants and animals and has evolved for the sole purpose of secreting virulence factors in both plant and animal pathogens. Thus, mechanisms of microbial pathogenesis are evolutionarily ancient and most, if not all, bacterial pathogens share common means of attacking their hosts, even if the hosts are in different taxonomic kingdoms. Dr. Collmer’s laboratory also showed that harpins are produced not only by P. syringae pathovars that cause specialized genotype-specific diseases, but also by nonspecialized pathogens, such as E. chrysanthemi, that cause soft rots.
Dr. Collmer’s teaching contributions are reflected by the outstanding graduate and undergraduate students he has trained and by the core graduate course he has developed at Cornell, which exposes students to concepts, terminology, current topics, tools, and techniques of plant pathology from the molecular to organismal levels. He was a corecipient of the APS Foundation Genesis Program Award for Academic Development and has been invited to participate in several conferences dealing with teaching skills and resources. In addition to his many original research articles, Dr. Collmer regularly contributes reviews and participates in the scientific publication process by serving as an editor for two professional journals.