The artificial protein Octarellin V.1 (hltp://dx.doi.org/10.1016/j.jsb. 2016.05.004 [1]) was obtained through a direct evolution process over the de novo designed Octarellin V (hltp://dx.doi.org/10.1016/S0022-2836(02)01206-8 [2]). The protein has been characterized by circular dichroism and fluorescence techniques, in order to obtain data related to its thermo and chemical stability. Moreover, the data for the secondary structure content studied by circular dichroism and infra red techniques is reported for the Octarellin V and V.1. Two crystallization helpers, nanobodies (hltp://dx.doi.org/10.1038/nprot.2014.039 [3]) and alpha Rep (hltp://dx.doi.org/10.1016/j.jmb.2010.09.048 [4]), have been used to create stable complexes. Here we present the data obtained of the binding characterization of the Octarellin V.1 with the crystallization helpers by isothermal titration calorimetry. (C) 2016 The Authors. Published by Elsevier Inc.