A cyanobacterium which lacks thylakoids
- Cite this article as:
- Rippka, R., Waterbury, J. & Cohen-Bazire, G. Arch. Microbiol. (1974) 100: 419. doi:10.1007/BF00446333
Gloebacter violaceus gen. and sp. n. is a unicellular photosynthetic prokaryote of unusual cellular structure. The only unit membrane in the small, rod-shaped cells is the cytoplasmic membrane, which has a simple contour, without intrusions. Immediately underlying it is an electron-dense layer 80 nm thick. Gloeobacter is an aerobic photoautotroph which contains chlorophyll α, β-carotene and other carotenoids, allophycocyanin, phycocyanin and phycoerythrin. Chlorophyll and carotenoids are associated with the particulate fraction of cell-free extracts, and are thus probably localized in the cytoplasmic membrane. The phycobiliproteins may be associated with the electron-dense 80 nm layer. The DNA contains 64.4 moles percent GC. The cellular lipids have a high content of polyunsaturated fatty acids, largely linoleate and γ-linolenate. Despite its atypical fine structure, Gloeobacter is evidently a cyanobacterium, sufficiently different from other unicellular cyanobacteria to be placed in a new genus.
Key wordsGloeobacter violaceus Photosynthetic Pigments DNA Base Composition Fatty Acid Composition Cyanobacterium Ultrastructure
guanine + cytosine
3-(3,4 dichlorophenyl)-1,1 dimethyl urea