ABSTRACT
A defining moment in the history of active transport research came in August 1960, in a symposium at the Czeckoslovak Academy of Sciences, which became known among membrane biologists as the Prague Symposium (Kleinzeller and Kotyk, 1961). By that date, the enzymatic nature of sodium transport in animal cells had been demonstrated (Skou, 1957) and a generalized concept of transport-related, vectorial metabolism was being formulated (Mitchell, 1961). Specifically concerning uptake of organic metabolites, a pivotal observation had been made by Riklis and Quastel (1958): that active transport of sugars by intestinal villus membrane is dependent upon sodium ions in the luminal bathing solution. This finding was extended by Crane et al. (1961), who suggested in Prague that sugar and sodium ions might be simultaneously transported, and was further discussed by Mitchell. Subsequently, both Crane and Mitchell elaborated hypotheses of ion-coupled sugar transport: Na+–glucose in mammalian intestine (Crane, 1962) and H+–galactoside in Escherichia coli (Mitchell, 1962), which became incorporated into a comprehensive picture of proton-linked ‘chemiosmotic’ processes in bioenergetics.
