Long distance currents between proteins in water

Pau Gorostiza – Institut de Bioenginyeria de Catalunya (IBEC) and Carme Rovira – Universitat de Barcelona (UB)

Despite the importance of electron transfer between proteins in photosynthesis and cellular combustion, the electric current between partner proteins has never been measured as a function of their separation in water. Here, we use electrochemical tunneling spectroscopy to show that the current between two protein partners decays along more than 10 nm in the solution, ten times farther than expected. Computer simulations reveal that water is “desalted” between the proteins, which causes an extended electric field. Proteins could use this long distance current mechanism in order to interact specifically but not strongly, thus keeping high turnover rates in the crowded environment of cells.

References

Lagunas A, Guerra-Castellano A, Nin-Hill A, Díaz-Moreno I, De la Rosa MA, Samitier J, Rovira C & Gorostiza P 2018, ‘Long distance electron transfer through the aqueous solution between redox partner proteins’, Nat Commun. 9(1):5157.

Long distance currents between proteins in water

Pau Gorostiza – Institut de Bioenginyeria de Catalunya (IBEC) and Carme Rovira – Universitat de Barcelona (UB)

Lagunas A, Guerra-Castellano A, Nin-Hill A, Díaz-Moreno I, De la Rosa MA, Samitier J, Rovira C & Gorostiza P 2018, ‘Long distance electron transfer through the aqueous solution between redox partner proteins’, Nat Commun. 9(1):5157.

Computer simulations of protein partners hCc (left, orange) and pCc1 (right, green) indicate that water is “desalted” between the proteins, which causes an extended electric field. Heme groups are highlighted in each protein. Image credit: Alba Nin-Hill.