Poly intracellular degradation

Surprisingly, the fine regulation of the enzymes involved in poly(3HB) degradation has been hardly investigated at all (cf. Chap. 10 of this book). Most of the research on intracellular mobilization of poly(3HB) and oxidation of the monomers was done more than 25 years ago. 

The mechanism of the intracellular degradation of poly(HA) by bacteria, i.e., the mobilization of a previously accumulated polyester, is poorly understood (see also the chapter by Babel et al. in this book). Most of the research on intracellular poly(3HB) mobilization was done more than 30 years ago. Lemoigne observed in 1925 that 3-hydroxybutyrate was the main product of anaerobic breakdown of poly(3HB) in Bacillus M [12,137]. Macrae and Wilkinson [138, 139] noticed a reduction of the poly(3HB) content of Bacillus megaterium upon aerobic incubation of poly(3HB)-rich cells in phosphate buffer. The authors found that autolysis of poly(3HB)-rich cells occurred later and to a minor extent compared to poly(3HB)-poor cells and proposed that poly(3HB) might... 

Akagi T, Shima F, Akashi M (2011) Intracellular degradation and distribution of protein-encapsulated amphiphilic poly(amino acid) nanoparticles. Biomaterials 32 4959 1967... 

Woodward S, Brewer P, Montamed F, Schindler A and Pitt D (1985). The intracellular degradation of poly (epsilon-caprolactone) ,/. Biomed. Mater. Res., 19,437-444. 

Woodward, S.C., et al., 1985. The intracellular degradation of poly(epsilon-caprolactone). Journal of Biomedical Materials Research 19 (4), 437—444. Available at http //www.ncbi. nlm.nih.gov/pubmed/4055826. 

Figure 11.1 The intracellular trafficking pathway of plasmid DNA complexed by poly cationic lipid (lipoplex). Critical steps are indicated by numbers (1) endocytosis, sorting and recycling via vesicular compartments comprising the early (EE) and sorting endosomes (2) entrapment and degradation in the late-endosomes (LE) and lysosomes (3) destabilization of the endo-lysosomal membrane and release into the cytosol, (the precise location of this step is not known) (4) diffusion toward the nuclear pore complex (NPC) and degradation in the cytoplasm, and (5) nuclear translocation across the NPC.

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