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This is what bacterial sex looks like

magnified by electron microscopy. Bacterial sex starts when the male bacterium (donor) hooks the female (recipient) with his pilus, the long protein strand linking the two cells. Then he draws her close, making contact. Bacterial coitus begins! The male transfers some genes, in a linear order, into the female cell. One of the genes inserted actually transforms the female into a male, making her/him fertile and capable of transferring genes to other bacteria. Sounds infectious, no? It’s the bacterial twist on sexually transmitted disease, more like a sex-change infection!

Unlike sexual reproduction, the way plants and animals “do it”, bacterial sex is separate from reproduction. Bacteria reproduce by simply splitting two, producing two identical daughter cells, or clones. Bacterial sex is the direct transfer of genes to other bacteria, even other species.

 

Esther Zimmer & Joshua Lederberg 1946
The courtship. A romantic dinner, 1946

This is what bacterial love looks like.

These two lovebirds, Esther Zimmer and Joshua Lederberg, were married on Friday the 13th, 1946 in New Haven, CT. The precocious couple—he was 21 and she 23—moved to Madison, Wisconsin in 1947 to establish the first laboratory devoted to bacterial genetics. The young prodigies were quite serious about their unusual partnership: “We had a clear contract: we would keep house with symmetrical responsibilities,”recalled Joshua Lederberg, “and acknowledge the primacy (if not supremacy) of the obligations of scientific work. The serious young couple honeymooned at the annual AAAS–American Association for the Advancement of Science–meeting in Boston. What fun!        

During the decade leading up to the discovery of the double helix, this unique research couple transformed genetics by discovering the strange world of bacterial sex. The dynamic bacterial genome provided the tools and concepts necessary for the biotechnology revolution. The surprising capacity of bacteria to shuttle groups of genes to and fro among the wider microbial ecosystem has informed the current crisis of antibiotic-resistance pathogens. The ancient spreading of bacterial genes among prokaryotes and eukaryotes has fundamentally altered the tree of life.

This website is dedicated to telling the stories of Esther Lederberg’s life and career. Her achievements were hidden in the glare of Joshua Lederberg’s brilliance, but they contributed to his Nobel prize in 1958. By redirecting the light of recognition and highlighting the high esteem of her colleagues, I hope to balance the record of Esther Zimmer Lederberg, the “mother of bacterial genetics.”