This paper describes the development of medical applications for polyhydroxyalkanoates (PHAs), a class of natural polymers with a wide range of thermoplastic properties. Methods are described for preparing PHAs with high purity, modifying these materials to change their surface and degradation properties, and methods for fabricating them into different forms, including tissue engineering scaffo...

The group A streptococcus (GAS), Streptococcus pyogenes, is an important human pathogen that causes infections ranging in severity from self-limiting pharyngitis to severe invasive diseases that are associated with significant morbidity and mortality. The pathogenic effects of GAS are mediated by the expression of virulence factors, one of which is the hyaluronic acid capsule (encoded by genes ...

Many attempts to create bio-plastics from renewable resources have been made in recent years. The main aim of these studies has been to develop products competitive with synthetic polymers. Two main strategies have been studied to produce reasonable yields of these polymers: transgenic plant cells1 and the well known bacterial fermentation process.2 Among the various candidates for biodegradabl...

Polyhydroxyalkanoates (PHAs) are biodegradable polymers produced by microbes to overcome environmental stress. Commercial production of PHAs is limited by the high cost of production compared to conventional plastics. Another hindrance is the brittle nature and low strength of polyhydroxybutyrate (PHB), the most widely studied PHA. The needs are to produce PHAs, which have better elastomeric pr...

Received 16.11.2015, received in revised form 17.01.2016, accepted 02.03.2016 The paper describes research of biomedical applications of experimental polymer devices prepared from polyhydroxyalkanoates (PHAs) in the Institute of Biophysics SB RAS and Siberian Federal University (Krasnoyarsk, Russia) between 2000 and 2012. The high-purity PHA specimens were investigated and then used to prepare ...

The phas promoter is potently transcribed during embryogenesis but in vegetative tissues it is completely silenced by a rotationally positioned nucleosome. Ectopic expression in leaves of PvALF, a seed-specific transcription factor belonging to the plant-exclusive B3 domain-containing VP1/ABI3 family, leads to chromatin remodeling of the phas promoter, permitting transcriptional activation by t...

Lignin is an energy-dense, heterogeneous polymer comprised of phenylpropanoid monomers used by plants for structure, water transport, and defense, and it is the second most abundant biopolymer on Earth after cellulose. In production of fuels and chemicals from biomass, lignin is typically underused as a feedstock and burned for process heat because its inherent heterogeneity and recalcitrance m...

Polyhydroxyalkanoates (PHAs) are microbial polyesters produced by various microorganisms. Many of these bacteria when fed with suitable carbon sources can produce PHAs up to about 30 wt% of the cell dry weight (CDW) and a few such as Ralstonia eutropha can accumulate PHAs up to almost 90 wt% of the CDW. In cyanobacteria (blue-green algae), the PHA content is usually about 5 wt% of the CDW. In t...

Together with other so-called "bio-plastics", Polyhydroxyalkanoates (PHAs) are expected to soon replace established polymers on the plastic market. As a prerequisite, optimized process design is needed to make PHAs attractive in terms of costs and quality. Nowadays, large-scale PHA production relies on discontinuous fed-batch cultivation in huge bioreactors. Such processes presuppose numerous s...