Bacteria energy storage

Polyhydroxyalkanoates (PHAs) are biological polyesters that are produced by a wide variety of bacteria as osmotically inert carbon- and energy-storage compounds that accumulate in the form of granules (see Fig. 1). 

Glycogen Homo- (al—>4)Glc, with (a 1—>6)Glc branches every 8-12 residues Up to 50,000 Energy storage in bacteria and animal cells... 

Dextran is a naturally occurring polymer that is synthesized in yeasts and bacteria for energy storage. It is mainly a linear polysaccharide consisting of repeating units of... 

Polyhydroxyalkanoate (PHA) is a polyester of hydroxyalkanoates synthesized by numerous bacteria as an intracellular carbon and energy storage compound and accumulated as granules in the cytoplasm of cells... 

Another class of energy storage compounds consists of redox couples such as NADP+-NADPH (Table 6-1). The reduced form, NADPH, is produced by noncyclic electron flow in chloroplasts (Chapter 5, Section 5.5C). Photosynthesis in bacteria makes use of a different redox couple, NAD+-NADH. The reduced member of this latter couple also causes an... 

An additional advantage of the polyhydroxyalkanoates is that the polymers can be produced by fermentation. Certain types of bacteria produce PHAs for energy storage when they are grown in glucose solution in the absence of specific nutrients. The polymer forms as discrete granules within the bacterial cell, and it is then removed by extraction to give a white powder that can be melted and modified into a variety of different products. 

Gum Arabica is a natural plant gum that exudates a carbohydrate type and is an electroactive biopolymer. Gum Arabica and its complexes have potential applications in developing ionic devices such as batteries, sensors, bio-sensors, and other electronic applications, in addition to solar material, energy storage material and nanoscience. Biopolymers obtained from bacteria are rapidly emerging because they are biodegradable and available in abundance. Simple methods are being developed to grow and harvest the polymers to exploit them for numerous industrial and biomedical applications. Electronic structures and conduction properties of biopolymers are also discussed in Part III. 

Researchers in industry have also reported working on methods with which transgenic crops will be developed that express PHA synthesis routes from bacteria to produce PHA as energy storage in their tissues [16]. 

Adenosine triphosphate (ATP) is employed by all multicellular organisms for energy storage and transfer, but some bacteria (e.g. Rhodospirillum rubrum and Proprionibacterium shermanii) use inorganic pyrophosphate, and so does the dysentery-causing protozoon Entamoeba histolytica. The work of ATP is assisted... 

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