Polyhydroxybutyrate particles in Synechocystis sp PCC 6803: facts and fiction
Transmission electron microscopy has been used to identify poly-3-hydroxybutyrate (PHB) granules in cyanobacteria for over 40 years. Spherical inclusions inside the cell that are electron-transparent and/or slightly electron-dense and that are found in transmission electron micrographs of cyanobacteria are generally assumed to be PHB granules. The aim of this study was to test this assumption in different strains of the cyanobacterium Synechocystis sp. PCC 6803. Inclusions that resemble PHB granules were present in strains lacking a pair of genes essential for PHB synthesis and in wild-type cells under conditions that no PHB granules could be detected by fluorescence staining of PHB. Indeed, in these cells PHB could not be demonstrated chemically by GC/MS either. Based on the results gathered, it is concluded that not all the slightly electron-dense spherical inclusions are PHB granules in Synechocystis sp. PCC 6803. This result is potentially applicable to other cyanobacteria. Alternate assignments for these inclusions are discussed.
- Sponsoring Organization:
- USDOE Advanced Research Projects Agency - Energy (ARPA-E)
- DOE Contract Number:
- DE-AR0000011
- OSTI ID:
- 1210992
- Journal Information:
- Photosynthesis Research, Vol. 118, Issue 2-Jan; ISSN 0166-8595
- Country of Publication:
- United States
- Language:
- English
Similar Records
Metabolic engineering of the pentose phosphate pathway for enhanced limonene production in the cyanobacterium Synechocysti s sp. PCC 6803
An integrative approach to energy, carbon, and redox metabolism in the cyanobacterium Synechocystis sp. PCC 6803