Nechama Gilboa-Garber's 55-Year Contribution to Glycobiology

My (Nechama Gilboa-Garber's) pioneering contributions to glycobiology started with the discovery of PA-IL, the first bacterial lectin. Concomitantly, we (Nechama Gilboa-Garber and coworkers) discovered the hitherto unknown PA cholinesterase that releases choline (Ch). Ch oxidation by two PA dehydrogenases to the osmolyte glycine betaine was shown by us to stimulate the expression of PA lectins and additional PA virulence factors (VIFs) via quorum sensing (QS). After discovering the amino acid sequences of the five bacterial lectins, we isolated their genes and expressed them in E. coli. This advancement enabled us to analyze the glycan affinities of these lectins-using special crystallographic and entropy studies. These analyses revealed the 3D structures of the five bacterial lectins and their detailed specific interactions with saccharides, especially branched glycans. Our studies on the effects of PA lectins on cells revealed changes in the target cell membranes. Our studies on the functions of the PA lectins have shown that their anchoring to cells enables maximal damaging effects on their targets. Since the bacterial lectins are involved in infection establishment, we found them highly advantageous as powerful probes for detecting animal and plant glycodecoys that protect their embryos (in seeds, fruits, and avian egg whites), neonates (in milk, royal jelly, and honey), and sensitive cells (seminal plasma, tears, saliva) from infections, and might be of medical and agricultural importance.