Winthrop John Van Leuven Osterhout (August 2, 1871 – April 9, 1964) was an American botanist.
In 1899 he received a Ph.D. at the University of California with a dissertation on Rhabdonia,[1] whereupon he married his first wife, Anna Maria Landstrom.
In 1909, he moved to Harvard University as an assistant professor of botany, taking a step down in rank but being closer to the important Marine Biological Laboratory at Woods Hole.
[5] The death of Loeb in 1924 left a vacancy at the Rockefeller Institute, and Osterhout joined the staff in 1926.
[1] During the 1930s, he was the first to suggest the active transport mechanism of a carrier molecule for moving solutes across a cell membrane.