Bacterial storage

The important bacterial storage material poly-hydroxybutyric acid is related metabolically and structurally to the lipids. This highly reduced polymer is made up of D-(3-hydroxybutyric acid units in ester linkage, about 1500 residues being present per chain. The structure is that of a compact right-handed coil with a twofold screw axis and a pitch of 0.60 nm.a Within bacteria it often occurs in thin lamellae 5.0 nm thick. Since a chain of 1500 residues stretches to 440 nm, there must be 88 folds in a single chain. Present in both cytoplasmic granules and in membranes,b polyhydroxybutyrate can account for as much as 50% of the total carbon of some bacterial In E. coli and many other bacteria polyhydroxybutyrate is present in a lower molecular mass form bound to calcium polyphosphates, proteins, or other macromolecules.d e It has also been extracted from bovine serum albumin and may be ubiquitous in both eukaryotes and prokaryotes.d/e The polymer may function in formation of Ca2+ channels in membranes.b/d... 

High (C P)org in anoxic sediments results from hmited bacterial storage of P extensive P-regeneration, and enhanced Corg preservation. 

The synthesis of bacterial storage compounds is reviewed in Chapter 10, focusing on two systems, namely polyhydroxyalkanoic acids and cyanophycin. Bacterial storage compounds are very interesting biopolymers having attractive material properties, sometimes similar to those of the petrochemical-based polymers. 

The important bacterial storage material poly-hydroxybutyric add is related metabolically and structurally to the lipids. This highly reduced polymer is made up of o-P-hydroxybutyric acid units in ester linkage, about 1500 residues being present per chain. The structure is that of a compact right-handed coil with a twofold screw axis and a pitch of... 

PHB Poly-3-hydroxybutyrate Bacterial storage polyester slowa degradation rate tiimi polylactic polymers... 

K. Grage, V. Peters, R. Palanisamy, B.H.A. Rehm, Polyhydroxyal-kanoates from bacterial storage compound via alternative plastic to bio-bead, in B.H.A. Rehm (Ed.), Microbial Production of Biopolymers and Polymer Precursors Applications and Perspectives, Caister Academic Press, Norfolk, UK, 2009, pp. 255-287. 

Microalgal hydrocarbons are an example where molecular genetic improvements and transgenic expression can also be tested in the natural host or its close phylogenetic relatives (21). Each feedstock production and conversion system, whether based on plants, microbes, or chemistry, has its pros and cons, and there is no one universal platform for foreseeable future (22). Host-compound choices must therefore be taken on a case-by-case basis. Poly-B-hydroxyalkanoates as biodegradable polyesters are bacterial storage polymers and can be produced by fermentation on cheap starch hydrolysate with high volume and biomass yield (23). Nevertheless, commercialization of the compound as a bulk polymer so far has not been accomplished because the... 

Polyhydroxyalkanoates (PHAs), also known as microbial polyesters , or bacterial plastics are biosynthetic, biocomapatible, and biodegradable thermoplastics. They are bacterial storage polymers produced by various microorganisms (e.g., A.eutrophus, P.oleovorans, R.rubrum, Rb.spaeroides) in response to nutrient limitation occuring in the presence of an excess of carbon (see Chapters 9 and 10), and function as intracellular reserves of carbon and energy as well as ion sinks. 

Obst, M., Steinbiichel, A., 2006. Cyanophycin-an ideal bacterial storage material with unique chemical properties. Microbiology Monographs 1 In Shively, J.M., (Ed.) Inclusions in Prokaryotes. Springer Verlag, Berlin, Heidelgerg, pp. 168-187. 

Freguia, S., Rabaey, K., Yuan, Z. and Keller, J. (2007) Electron and carbon balances in microbial fuel cells reveal temporary bacterial storage behavior during electricity generation Environ. Sci. Technol. 41(8), 2915-2921. 

BOECK, G., and bossier, p. (2009) The bacterial storage compound poly- 3-hydroxybutyrate (PHB) increases growth performance and intestinal bacterial range-weighted richness in juvenile European sea Applied Microbiology and Biotechnology 86 1535-1541. 

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