[Intensification of synthesis of the exopolysaccharide ethapolan by Acinetobacter sp. 12S grown on a mixture of substrates].
Enhanced synthesis of the exopolysaccharide (EPS) ethapolan by Acinetobacter sp. 12S was observed when the bacterium was grown on a mixture of two energetically nonequivalent substrates (ethanol and glucose) taken in a molar proportion of 3.1:1. The efficiency of carbon transformation into EPSs was maximum when sodium ions were absent in the medium, the concentration of nitrogen source was reduced to 0.3-0.45 g/l, and the inoculum was grown on ethanol. Such conditions provided an increase in the maximum specific growth rate and its attainment in earlier cultivation terms. Molasses as a substitution for glucose was inefficient. The activities of the key enzymes of C2-metabolism in Acinetobacter sp. 12S cells grown on the substrate mixture was 1.1 to 1.7 times lower than they were during growth on ethanol alone. The activity of isocitrate lyase in cells grown on the substrate mixture declined to an even greater extent (by 4 to 7 times), indicating that the role of the glyoxylate cycle in such cells is insignificant.
Pirog
T P
TP
Zabolotnyi Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, ul. Zabolotnogo 154, Kiev, 03143 Ukraine.
Kovalenko
M A
MA
Kuz'minskaia
Iu V
IuV
Krishtab
T P
TP
D000150:Acinetobacter / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media; D000431:Ethanol / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D009584:Nitrogen; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D012964:Sodium; D013379:Substrate Specificity
D003470:Culture Media; D011135:Polysaccharides, Bacterial; D000431:Ethanol; D012964:Sodium; D005947:Glucose; D009584:Nitrogen
Intensifikatsiia sinteza ékzopolisakharida étapolana na smesi rostovykh substratov.