(B) Electrostatic surface representations of the modelled wild-type GRAM1b (WT) and mutant versions of GRAM1b carrying mutations that are predicted to alter charge distribution of the basic patch (basic patch mutants: K161A, R191A, and K161A/R191A). Blue indicates positively charged surface, while red indicates negatively charged surface at the level of ±2 kT/e. The electrostatic surface representations were generated by APBS Electrostatics plugin using PyMoL. The dashed boxes indicate the positions of the mutated amino acid residues. 