This study set out to recombinantly produce the novel peptide K-Theraphotoxin-Aa1a, a selective blocker of the voltage-gated potassium channel Kv10.1, to facilitate characterisation of its functional properties and assess its potential for scalable production. The Aa1a gene was inserted into the pPICZαA expression vector and verified by whole-plasmid sequencing, and expression in Pichia pastoris yielded two predominant heterogeneous isoforms. Mass spectrometry confirmed the expected amino acid sequence in both isoforms, although one lacked a His-tag.