This is the peer reviewed version of the following article: Sun, H., Yeo, W. L., Lim, Y. H., Chew, X., Smith, D. J., Xue, B., … Ang, E. L. (2016). Directed Evolution of a Fluorinase for Improved Fluorination Efficiency with a Non-native Substrate. Angewandte Chemie International Edition, 55(46), 14277–14280. doi:10.1002/anie.201606722, which has been published in final form at http://dx.doi.org/10.1002/anie.201606722. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.