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"This could be the right answer :-)"
hi
This ("Protein") was the right answer to some extent/in some sense,
(The majority (or all, I don't know yet) of molecules in this league are gonna be proteins.)
but this contest requires more specificity

ATP synthase is the right answer.
https://en.wikipedia.org/wiki/ATP_synthase
This time we have a winner (see comments section).

thanks for your interest/participation for/in the "Identify the molecule" league )