---
title: "Matthew J. Guberman-Pfeffer"
type: "entity"
entity_kind: "person"
status: "hub"
canonical_name: "Matthew J. Guberman-Pfeffer"
aliases: ["Guberman-Pfeffer"]
first_seen: "2026-08-07T00:00:00.000Z"
writer_model: "claude-opus-4-8"
connects_to: ["Geobacter sulfurreducens","extracellular electron transfer","redox hopping","Marcus theory","microbial nanowires"]
seek_code_commit: "649b1a4"
---


A computational biochemist (Baylor University) who models electron transfer
through multi-heme proteins using non-adiabatic [[entity-marcus-theory|Marcus
theory]]. His 2024 *Frontiers in Microbiology* perspective, "To be or not to be
a cytochrome: electrical characterizations are inconsistent with *Geobacter*
cytochrome 'nanowires'," argues that the measured currents reported for
*Geobacter* cytochrome nanowires exceed by 10²–10⁵-fold the maximum a heme wire
could physically carry by [[entity-redox-hopping|redox hopping]] — while still
affirming that the filaments are cytochromes.

Matters to this vault as the fourth, largely independent voice in the
*[[entity-geobacter-sulfurreducens|Geobacter]]* nanowire dispute: not aligned in
this paper with either the [[entity-derek-lovley|Lovley]] e-pili camp or the
[[entity-nikhil-malvankar|Malvankar]] cytochrome camp, he grants the cryo-EM
structural identity and attacks the electrical *measurements* instead
([[claim-guberman-pfeffer-blames-measurement-not-cytochrome-identity]]). His
contribution is a computed-physics prong — a Marcus-theory upper bound on
redox-hopping current the reported conductivities are measured against
([[claim-guberman-pfeffer-0-14-pa-ceiling-is-computed-not-measured]]).

## References
- [[claim-2024-paper-disputes-geobacter-cytochrome-nanowire-conductivity]]
- [[claim-guberman-pfeffer-0-14-pa-ceiling-is-computed-not-measured]]
- [[claim-guberman-pfeffer-blames-measurement-not-cytochrome-identity]]