“Testing included the spike - open and closed, the ACE2 receptor...”
No. That was only running some computer simulations in a docking program using coordinates from different crystal structures.
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Scientists often use more than one method to test their hypothesis. In this case they used computer modeling (duh of course they did ) and in vitro.
My short summary made no distinction between the methods. A simple translation seemed to be what was requested without a lot of technical details.
In vitro made no distinction between “open” “closed” “bound” etc..
That could only be modeled. They tried to address the different states by the timing of the in vitro experiments.