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Induction of orientation of bacterial cellulose microfibrils by a novel terpenoid from Acetobacter xylinum
- Source :
- The Biochemical journal. 135(1)
- Publication Year :
- 1973
-
Abstract
- 1. The bacterium Acetobacter xylinum produces extracellular cellulose microfibrils that form a pellicle in the medium enmeshing the bacterial cells. These microfibrils may show some localized alignment, which can be seen as birefringence when the culture is viewed between crossed Polaroid sheets. 2. An increase in birefringence can be induced by the addition of small amounts of certain classes of lipids, particularly sterols, to the cultures. 3. A crude lipid extract from Acetobacter cells induced greatly increased birefringence when added to fresh cultures of this organism. 4. When the bacterial lipids were fractionated, most of the activity was recovered in a complex, polar lipid. The lipid is secreted into the medium during growth and is unstable. The non-saponifiable portion of this lipid is shown to be a 1:1 mixture of a saturated and a monounsaturated C35 tetrahydroxy terpene with a hopane ring system in the accompanying paper by Förster et al. (1973). The saturated molecule is referred to as tetrahydroxybacteriohopane. 5. Tetrahydroxybacteriohopane is itself capable of inducing birefringence in cultures as is 22-hydroxyhopane, which was also isolated from the non-saponifiable fraction of the total lipids. 6. The mechanism of induction of birefringence (orientation of microfibrils) is not known. This is unlikely to be a specific effect, since all the above compounds are active (intact lipid, tetrahydroxybacteriohopane, 22-hydroxyhopane), as are other classes of lipid. It is suggested, however, that a common mechanism may be involved and that similar compounds may be concerned with control of microfibril alignment in the cells of higher plants.
- Subjects :
- Spectrophotometry, Infrared
Gluconacetobacter xylinus
Molecular Conformation
Biochemistry
Chromatography, DEAE-Cellulose
chemistry.chemical_compound
Extracellular
Cellulose
Molecular Biology
Birefringence
biology
Terpenes
Cell Biology
biology.organism_classification
Lipids
Terpenoid
chemistry
Bacterial cellulose
Alcohols
Microscopy, Electron, Scanning
Microfibril
Acetobacter
Bacteria
Subjects
Details
- ISSN :
- 02646021
- Volume :
- 135
- Issue :
- 1
- Database :
- OpenAIRE
- Journal :
- The Biochemical journal
- Accession number :
- edsair.doi.dedup.....e1bde76805268699495e3601a3524d11