Poly-beta-hydroxybutyrate accumulation and releasing by hydrogen producing bacteria, Rhodobacter sphaeroides OU001. A transmission electron microscopic study

Date

2006-11-16

Author

Cetin, Demet
Guenduez, Ufuk
Eroğlu, İnci
Yuecel, Meral
Tuerker, Lemi

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Photosynthetic bacterium Rhodobacter sphaeroides O.U.001 that is used for photobiohydrogen production can also accumulate poly-beta-hydroxybutyrate (PHB) as a by-product when cultivated anaerobically with minimal medium containing L-malic acid, sodium glutamate and some vitamins under illumination. Transmission electron microscopy studies revealed that PHB granules are made of two distinct components: a homogenous and electron lucent core is covered with a more electron dense coat. PHB granules were observed in the cytoplasm, outside of the cells, in the center of cotton like aggregates in the cells, or while they were being released from the cell. In this study, two kinds of releasing were revealed; with lysis and without lysis of cell wall. Release of intact polymer outside the cells could be economically feasible way to obtain PHB for industrial applications.

Subject Keywords

Poly-beta-hydroxybutyrate, PHB, Rhodobacter sphaeroides, Transmission electron microscopy

URI

https://hdl.handle.net/11511/52671

Journal

AFRICAN JOURNAL OF BIOTECHNOLOGY

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

D. Cetin, U. Guenduez, İ. Eroğlu, M. Yuecel, and L. Tuerker, “Poly-beta-hydroxybutyrate accumulation and releasing by hydrogen producing bacteria, Rhodobacter sphaeroides OU001. A transmission electron microscopic study,” AFRICAN JOURNAL OF BIOTECHNOLOGY, pp. 2069–2072, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52671.