"...quite obvious answer: Protein."
hi
yes, you're right to some extent/in some sense), it is a protein )
but this contest requires more specificity
The majority (or all, I don't know yet) of molecules in this league are gonna be proteins.

I understand that that was a joke )

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

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