In vivo deuteration of a native bacterial biopolymer for structural elucidation using SANS

Abstract

In order to facilitate future structural studies, biodeuteration of bacterial polyhydroxyalkanoates (PHAs) was investigated. We report here the in vivo deuteration of poly 3-hydroxyoctanoate (PHO) produced by its native host, the bacterium Pseudomonas oleovorans. Bacterial biomass was produced in bioreactor studies by growth on hydrogenated substrates and PHO was subsequently produced intracellularly (10–20% w/w) during batch fed growth on deuterated octanoic acid under oxygen limitation. GC-MS analyses of the PHO demonstrated that 13 of the 15 hydrogen atoms had been replaced with deuterium (except in position 3), the remaining two hydrogen presumably being derived from water. A SANS contrast variation study was conducted on whole cells and the results indicate the potential to discriminate inclusion bodies formed from deuterated precursor from an otherwise hydrogenated background. © 2004, Elsevier Ltd.