Formation of volutin granules in Corynebacterium glutamicum.
Volutin granules are intracellular storages of complexed inorganic polyphosphate (poly P). Histochemical staining procedures differentiate between pathogenic corynebacteria such as Corynebacterum diphtheriae (containing volutin) and non-pathogenic species, such as C. glutamicum. Here we report that strains ATCC13032 and MH20-22B of the non-pathogenic C. glutamicum also formed subcellular entities (18-37% of the total cell volume) that had the typical characteristics of volutin granules: (i) volutin staining, (ii) green UV fluorescence when stained with 4',6-diamidino-2-phenylindole, (iii) electron-dense and rich in phosphorus when determined with transmission electron microscopy and X-ray microanalysis, and (iv) 31P NMR poly P resonances of isolated granules dissolved in EDTA. MgCl2 addition to the growth medium stimulated granule formation but did not effect expression of genes involved in poly P metabolism. Granular volutin fractions from lysed cells contained polyphosphate glucokinase as detected by SDS-PAGE/MALDI-TOF, indicating that this poly P metabolizing enzyme is present also in intact poly P granules. The results suggest that formation of volutin is a more widespread phenomenon than generally accepted.
Pallerla
Srinivas Reddy
SR
Institut für Biotechnologie (IBT-1), Forschungszentrum Jülich, D-52425 Jülich, Germany.
Knebel
Sandra
S
Polen
Tino
T
Klauth
Peter
P
Hollender
Juliane
J
Wendisch
Volker F
VF
Schoberth
Siegfried M
SM
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D003594:Cytoplasmic Granules / Q000378:metabolism* / Q000648:ultrastructure; D004577:Electron Probe Microanalysis; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D007287:Inorganic Chemicals / Q000378:metabolism*; D015636:Magnesium Chloride / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D046529:Microscopy, Electron, Transmission; D020411:Oligonucleotide Array Sequence Analysis; D010759:Phosphorus Isotopes; D010770:Phosphotransferases / Q000378:metabolism; D011122:Polyphosphates / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
D001426:Bacterial Proteins; D007287:Inorganic Chemicals; D010759:Phosphorus Isotopes; D011122:Polyphosphates; D011506:Proteins; D015636:Magnesium Chloride; D010770:Phosphotransferases; C024812:polyphosphate-glucose phosphotransferase