A basis for utlization of unnatural pentoses and pentitols by Aerobacter aerogenes.

Abstract

Although not rigorously studied, it has long appeared that bacteria are unique in their ability to metabolize those organic materials which are rarely, if ever, found in nature. Aerobacter aerogenes, PRL R3, particularly illustrates this phenomenon with its ability to utilize as a source of energy seven of the eight aldopentoses and all four of the pentitols.' 2 Of this group of 11 structures, D-ribose, D-xylose, Larabinose, D-arabitol, and ribitol are found in nature, whereas D-arabinose, Dlyxose, L-xylose, L-lyxose, xylitol, and L-arabitol3 seem to be rarely, if ever, encountered in the natural environment.4 The routes of utilization of all of these C, compounds have been documented (Fig. 1).2. [5][6][7][8][9][10][11][12][13][14][15][16][17][18] Referring to Figure 1, it can be seen that metabolism of the unnatural compounds, D-lyxose and xylitol, for example, involves only one new or unique reaction for each, i.e., isomerization of D-lyxose or oxidation of xylitol to D-xylulose. The phosphorylation of D-xylulose is common to the route for utilization of D-xylose and D-arabitol, both naturally occurring substrates readily attacked by A. aerogenes. Similarly, the conversions of L-xylose, L-lyxose, and L-arabitol involve either isomerizations or an oxidation to L-xylulose.2 8 The subsequent reactions of the pathway are common to those for L-xylulose and L-ribulose2 19 which appear in nature as metabolic intermediates in utilization of L-ascorbate20 and L-arabi-*

Bioproduction ofD-Psicose from Allitol withEnterobacter aerogenesIK7: A New Frontier in Rare Ketose Production

“…Enzymes similar to Aerobacter aerogenes PRLR3 27) and Klebsiella aerogenes 28) catalyzed the oxidation of ribitol, L-arabitol, and xylitol. The pentitol specificity of the bacterium appeared to be similar to those of A. aerogenes PRLR3 and K. aerogenes.…”

“…The bacterium was grown at different temperatures, (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37) C) to optimize growth and activity. The highest biomass yield was obtained when it was incubated at 28 C ( Fig.…”

Constitutive activation of the fucAO operon and silencing of the divergently transcribed fucPIK operon by an IS5 element in Escherichia coli mutants selected for growth on L-1,2-propanediol

“…Following the discovery that a genetic derepression of ribitol dehydrogenase in Klebsiella pneumoniae conferred a growth ability on xylitol (27,33), we tried to find other models of experimental evolution for assessing the importance of regulatory mutations in the acquisition of novel functions (for a review, see reference 30). During this search, we discovered that Escherichia coli can give rise to mutants that utilize L-1,2-propanediol aerobically as a sole source of carbon and energy.…”

Studies on the Oxidation of Ribitol and D-Arabitol by Actobacter aceti IFO 3281

“…The oxidation of ribitol follows the rule in that a secondary hydroxyl group of a cis pair adjacent to a terminal alcohol group is oxidized (Dische and Borenfreund, 1951). In one report, L-ribulose was prepared from xylitol by refluxiing with dry pyridine from the corresponding aldopentose (Mortlock et al, 1965) where the oxidation of ribitol to L-ribulose was followed by a long lag period to attain complete oxidation; resulting in the formation of by-products. Microbiological and enzymatic production of D-xylulose from D-arabitol have been reported previously (Compello, 1973;Moses and Ferrier, 1962;Olsson et al, 1994).…”