Effects of mutations in the substrate-binding domain of poly[(R)-3-hydroxybutyrate] (PHB) depolymerase from Ralstonia pickettii T1 on PHB degradation

Article Abstract:

The interaction between denatured poly[(R)-3-hydroxybutyrte] (dPHB) depolymerase and the dPHB surface is investigated by a combination of PCR random mutagenesis targeted only to the substrate-binding domain (SBD) region and an in vivo screening system to identify the amino acid residues relating to dPHB adsorption. The kinetic analysis of the dPHB degradation suggested that lowering the affinity of the SBD towards dPHB causes a decrease in the dPHB degradation rate without the loss of its hydrolytic activity for the polymer chain.

Decomposition (Chemistry), Microbial genetics, Structure, Chemical properties, Report, Poly-beta-hydroxybutyrate

Coexpression of genetically engineered 3-Ketoacyl-ACP synthase III (fabH) and Polyhydroxyalkanoate synthase (phaC) genes leads to short-chain-length-medium-chain-length Polyhydroxyalkanoate copolymer production from glucose in Escherichia coli JM109

Article Abstract:

Polyhydroxyalkanoates (PHAs) are polyesters of 3-hydroxy alkanoic acids that are produced as intracellular granules by different bacteria. A study was conducted to prove that short0chain-length (SCL) medium-chain-length (MCL) PHAs can be made from glucose in recombinant E. coli.

Plastics Material and Resin Manufacturing, Alkyd & Polyester Resins, Methods, Causes of, Gene expression, Escherichia coli infections, Polyhydroxyalkanoates

Alteration of chain length substrate specificity of Aeromonas caviae R-enantiomer-specific enoyl-coenzyme A hydratase through site-directed mutagenesis

Article Abstract:

Research has been conducted on Aeromonas caviae R-specific enoyl-coenzyme A hydratase. The authors have investigated the feasibility of changing the acyl chain length substrate specificity of this hydratase via the use of site-directed mutagenesis.

Japan, Analysis, Physiological aspects, Environmental aspects, Genetic aspects, Microbiology, Microbial populations, Mutagenesis, Enantiomers, Coenzymes, Optical isomers, Microbial ecology