The Discovery of Membrane Vesicle Biogenesis in the Polyhydroxybutyrate-non-producing Mutant Strain of Cupriavidus necator H16.

Extracellular membrane vesicles (MVs) caused by the artificial production of polyhydroxybutyrate (PHB) were previously detected in Escherichia coli. We herein observed MV biogenesis in the mutant strain (-PHB) of the natural PHB producer, Cupriavidus necator H16. This inverse relationship was revealed through comparative electron microscopic ana-lyses of wild-type and mutant strains. Based on these results, we speculate that a physiological relationship exists between MV biogenesis and PHB biosynthesis. Therefore, we propose the potential of MV biogenesis as a fermentative "stress marker" for monitoring the performance of target polymer-producing microbial platforms.