Abstract

An important and understudied area in microbial ecology concerns the very large number of very rare species within an environment. Study of such species based on non-specific sequencing of environmental samples is practically difficult simply due to their rarity. A previous report demonstrated that pretreating samples with the photoactive dye PMA before subsequent PCR and sequencing can increase sensitivity to rare species. Here we propose a mathematical model based on equilibrium chemical thermodynamics that explains this effect and suggests a simple quantitative experiment.