Table 1. Nomenclature.

Acronym	Description
DSR	Dissimilatory sulfate reduction
SRO	Sulfate-reducing organism
EC	Electron carrier
R r/o	Ratio of reduced to oxidized electron carrier concentrations
csSRR	Cell-specific sulfate reduction rate
ΔG′°	Standard Gibbs free energy
E′°	Standard reduction potential
K M	Michaelis–Menten half saturation concentrations
α eq	Equilibrium fractionation factor
α kin	Kinetic fractionation factor
34 ε	S isotope enrichment factor;34 ε=(α−1) × 1000
MK	Menaquinone
Rb	Rubredoxin
Rd	Rubrerythrin
Fla	Flavodoxin
Cyt c3	Cytochrome c3
Fd	Ferredoxin