Cellulose Production by Acetobacter xylinum from Unlabeled Glucose and C¹⁴-Acetate and C¹⁴-Ethanol

CP/MAS 13C NMR Study of Cellulose and Cellulose Derivatives. 2. Complete Assignment of the 13C Resonance for the Ring Carbons of Cellulose Triacetate Polymorphs

“…The dilution and redistribution of the label was explained by the glycolysis and/or isomerization process during the glucosemetabolism of the strain such as the pentose-phasphate cycle, the Embden-Meyerhof, and the Entner-Doudoroff pathways. [18][19][20][21][22][23][24][25] The integral ratio of each carbon of the 13 C-enriched CTA II samples prepared from 13 C-labeled glucoses should be identical with those of the corresponding CTA I samples summarized in Table 1 because 13 C-enriched CTA polymorphs were prepared from the same 13 C-enriched cellulose. From these findings, since the intensity ratio of each carbon in the solidstate NMR spectra of these 13 C-enriched CTA I should be in complete agreement with the I.R.…”

“…In the case of CTA I from d -[5- 13 C]glucose, most of 13 C labeling (55.7%) was observed in the original position and transfers of labeling to C2 (9.0%) and C3 (11.1%) were also occurred. The dilution of the labeling of the original position in the introduced glucose as the carbon source and the redistribution of the label from the original position to other positions during the biosynthesis of cellulose by A. xylinum have been investigated by similar experiments with 14 C − - and 13 C 23-25 -enriched glucoses. The dilution and redistribution of the label was explained by the glycolysis and/or isomerization process during the glucose-metabolism of the strain such as the pentose-phasphate cycle, the Embden−Meyerhof, and the Entner−Doudoroff pathways. − The integral ratio of each carbon of the 13 C-enriched CTA II samples prepared from 13 C-labeled glucoses should be identical with those of the corresponding CTA I samples summarized in Table because 13 C-enriched CTA polymorphs were prepared from the same 13 C-enriched cellulose.…”

SYNTHESIS OF CELLULOSE BYACETOBACTER XYLINUMVI

“…In sugar-grown cells, synthesis from glucose and fructose was found to be inhibited by pyruvate and acetate (Schramm et al, 1957a). However, in A. xylinum cultures grown on mixtures of glucose and ethanol or acetate, these adjuncts, though not affording cellulose, stimulated cellulose synthesis from glucose (Minor et al, 1954;Greathouse et al, 1954). In ethanol-grown cells as in succinate-grown cells, under conditions in which pyruvate by itself afforded cellulose, the addition of pyruvate to glucose did not significantly affect the cellulose synthesis.…”

GROWTH AND EXTRACELLULAR POLYSACCHARIDE PRODUCTION BY RHIZOBIUM MELILOTI IN DEFINED MEDIUM

“…The possibility of increasing polysaccharide yields in bacterial cultures by using components of the tricarboxylic acid cycle in addition to a carbohydrate seems to have been neglected in studies with most bacteria. Acetate, citrate, and succinate are known to stimulate synthesis of cellulose by Acetobacter strains (Greathouse, Shirk, and Minor, 1954;Dudman, 1959). The present experiments show that succinate is effective with R. meliloti.…”