Dissipation during the Gating Cycle of the Bacterial Mechanosensitive Ion Channel Approaches the Landauer Limit

The Landauer principle sets a thermodynamic bound of k(B)T ln 2 on the energetic cost of erasing each bit of information. It holds for any memory device, regardless of its physical implementation. It was recently shown that carefully built artificial devices can attain this bound. In contrast, biological computation-like processes, e.g., DNA replication, transcription and translation use an order of magnitude more than their Landauer minimum. Here, we show that reaching the Landauer bound is nevertheless possible with biological devices. This is achieved using a mechanosensitive channel of small conductance (MscS) from E. coli as a memory bit. MscS is a fast-acting osmolyte release valve adjusting turgor pressure inside the cell. Our patch-clamp experiments and data analysis demonstrate that under a slow switching regime, the heat dissipation in the course of tension-driven gating transitions in MscS closely approaches its Landauer limit. We discuss the biological implications of this physical trait.

Automated summary

The Landauer principle sets a thermodynamic bound on the energetic cost of information erasure. Recent research shows that artificial devices can achieve this bound, while biological processes consume more energy. This study demonstrates that biological devices can still reach the Landauer bound using a mechanosensitive channel from E. coli as a memory bit. The experiments and data analysis show that the heat dissipation in the gating transitions of the channel closely approaches its Landauer limit.