Not exactly sure what you are asking. Proteins are used in the cell for all kinds of functions - for example one protein might be used in the process of breaking down a particular chemical.
The question of odds assumes first that proteins are even necessary for life, that the arrangement of molecules is even important. The a priori odds always assume life as we know it on Earth is the desired outcome. Proteins could be junk in the petri dish for another life form, and they wouldn't be caring what the odds were that it occurred.