Lipase catalysis in nonaqueous media is recognized as a powerful tool in organic and more recently polymer synthesis. Even though none of the currently known polyhydroxyalkanoate (PHA) depolymerases have lipase activity, they do have a catalytic center that resembles that of lipases. Motivated by the above, the potential of using the poly(3-hydroxybutyrate), PHB, depolymerase from Psuedomonas l...

BACKGROUND Poly-3-hydroxybutyrate (PHB) is a polyester with thermoplastic properties that is naturally occurring and produced by such bacteria as Ralstonia eutropha H16 and Bacillus megaterium. In contrast to currently utilized plastics and most synthetic polymers, PHB is biodegradable, and its production is not dependent on fossil resources making this bioplastic interesting for various indust...

Recently, syngas has gained significant interest as renewable and sustainable feedstock, in particular for the biotechnological production of poly([R]-3-hydroxybutyrate) (PHB). PHB is a biodegradable, biocompatible polyester produced by some bacteria growing on the principal component of syngas, CO. However, working with syngas is challenging because of the CO toxicity and the explosion danger ...

The present study focuses on sustainable production of biodegradable polymers by <br /> Cupriavidus necator DSMZ 545 using glycerol as substrate. batch growth and biopolymer kinetics were established in a 7-L bioreactor, which resulted total biomass 8.88 g L–1 poly(3-hydroxybutyrate) (PHB) accumulation 6.76 L–1. kinetic independently acquired substrate inhibition data then used to develop...

Poly(3-hydroxybutyrate) (PHB) is a natural biopolyester accumulated in microbial cells as tiny amorphous granules. The nanomicro-particles have a variety of potential applications and behave differently in different environments. In this work, the in situ crystallization of native PHB granules was investigated under different environmental conditions. The isothermal crystallization kinetics of ...

The granules observed in the cytoplasm of cells of sporogenic and asporogenic strains of Clostridium botulinum type E were isolated at various developmental stages of growth and sporulation. Electron microscopy of thin sections showed that most of the granules were dispersed throughout the cytoplasm. Chemical analysis and electron microscopy showed that the granules were poly-beta-hydroxybutyra...

Intensive aquaculture releases large quantities of nutrients into aquatic bodies, which can lead to eutrophication. The objective of this study was the development of a biological recirculatory wastewater treatment system with a diazotrophic cyanobacterium, Aulosira fertilissima, and simultaneous production of valuable product in the form of poly-β-hydroxybutyrate (PHB). To investigate this pos...

The biodegradation of methane, a greenhouse gas, and the accumulation of poly-β-hydroxybutyrate (PHB) were studied using a methanotrophic consortium and an isolated strain thereof. The specific rates for methane consumption were 100 and [Formula: see text] for the isolate and the consortium, respectively. Also the effect of including 10% (vv(-1)) of silicone oil in a two-phase partitioning bior...

The present study attempted to increase poly(3-hydroxybutyrate) (PHB) production by improving expression of PHB biosynthesis operon derived from Cupriavidus necator strain A-04 using various types promoters. intact C. A-04, an alkaline tolerant isolated in Thailand with a high degree 16S rRNA sequence similarity H16, was subcloned into pGEX-6P-1, pColdI, pColdTF, pBAD/Thio-TOPO, and pUC19 (nati...

The ascomycin-producer strain Streptomyces ascomycinicus has been proven to be an extracellular poly(R)-3-hydroxybutyrate (PHB) degrader. The fkbU gene, encoding a PHB depolymerase (PhaZ Sa ), has been cloned in E. coli and Rhodococcus sp. T104 strains for gene expression. Gram-positive host Rhodococcus sp. T104 was able to produce and secrete to the extracellular medium an active protein form....