Return enzyme concentrations in useful units

[codecov[bot]]

Codecov Report

Base: 88.49% // Head: 88.49% // No change to project coverage :thumbsup:

Coverage data is based on head (f515349) compared to base (33eef00). Patch has no changes to coverable lines.

Additional details and impacted files

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[stelmo]

So simplified enzyme does not have protein variables, so this is not needed there. Not sure what you mean for the second question?