A click chemistry approach to site-specific immobilization of a small laccase enables efficient direct electron transfer in a biocathode.

Controlled orientation of a small laccase on a multi-walled carbon nanotube electrode was achieved via copper-free click chemistry mediated immobilization. Modification of the enzyme was limited to only the tethering site and involved the genetic incorporation of the unnatural amino acid 4-azido-L-phenylalanine (AzF). This approach enabled efficient direct electron transfer.