Transporter characterisation reveals aminoethylphosphonate mineralisation as a key step in the marine phosphorus redox cycle.

ABSTRACT: The planktonic synthesis of reduced organophosphorus molecules, such as alkylphosphonates and aminophosphonates, represents one half of a vast global oceanic phosphorus redox cycle. Whilst alkylphosphonates tend to accumulate in recalcitrant dissolved organic matter, aminophosphonates do not. Here, we identify three bacterial 2-aminoethylphosphonate (2AEP) transporters, named AepXVW, AepP and AepSTU, whose synthesis is independent of phosphate concentrations (phosphate-insensitive). AepXVW is found in diverse marine heterotrophs and is ubiquitously distributed in mesopelagic and epipelagic waters. Unlike the archetypal phosphonate binding protein, PhnD, AepX has high affinity and high specificity for 2AEP (Stappia stellulata AepX K_d 23 ± 4 nM; methylphosphonate K_d 3.4

SUBMITTER: Murphy ARJ 

PROVIDER: S-EPMC8316502 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature