The amorphous state of bacterial poly[(R)-3-hydroxyalkanoate] in vivo

Poly[(R)-3-hydroxyalkanoate]s (PHAs) are bacterial storage polyesters which are accumulated by a range of microorganisms as intracellular granules. In contrast to the isolated PHA, the nascent polymer in the granules does not crystallize but remains amorphous at ambient temp. Numerous studies have been devoted to this phenomenon and all claimed the in vivo presence of a highly effective plasticizer. In contrast, this paper demonstrates that the native granules do not contain a plasticizer and that the amorphous state of in vivo PHA can be explained simply by straightforward crystn. kinetics