Disease relevance of arabino-2-Hexulosonic acid

• Characterization of the 2-ketogluconate utilization operon in Pseudomonas aeruginosa PAO1 [1].
• Production of gluconic acid and 2-ketogluconic acid by Klebsiella aerogenes NCTA 418 [2].
• 2-ketogluconic acid production and phosphate solubilization by Enterobacter intermedium [3].
• Gluconobacter oxydans DSM 2343 is known to catalyze the oxidation of glucose to gluconic acid, and subsequently, to 2-keto-D: -gluconic acid (2-KGA) and 5-keto-D: -gluconic acid (5-KGA), by membrane-bound and soluble dehydrogenases [4].

High impact information on arabino-2-Hexulosonic acid

• These results suggest that: (i) ptxS together with the other four ORFs constitute the 2-ketogluconate utilization operon (kgu) in P. aeruginosa [1].
• Furthermore, a plasmid carrying a fragment that contains ptxS and ORFs 1-4 complemented the defect of the previously described P. aeruginosa 2-ketogluconate-negative mutant [1].
• In contrast, the activities of other enzymes associated with this pathway (gluconate dehydrogenase, 2-ketogluconate kinase plus 2-ketogluconate-6-phosphate reductase) or with the 'internal' phosphorylative pathway of glucose metabolism (glucokinase and glucose-6-phosphate dehydrogenase) remained essentially unchanged [5].
• On the other hand, no gluconate and/or 2-ketogluconate production could be detected when K. pneumoniae was cultured at pH 8 [6].
• At pH values ranging from pH 5.5 to pH 6.0 maximal activity and synthesis of these enzymes resulted in a more than 80% conversion of the glucose consumed into gluconate and 2-ketogluconate under potassium- or phosphate-limited conditions [6].

Chemical compound and disease context of arabino-2-Hexulosonic acid

• Anaerobic 2-ketogluconate metabolism of Klebsiella pneumoniae NCTC 418 grown in chemostat culture: involvement of the pentose phosphate pathway [7].
• Klebsiella pneumoniae NCTC 418 is able to convert 2-ketogluconate intracellularly to 6-phosphogluconate by the combined action of an NADPH-dependent 2-ketogluconate reductase and gluconate kinase [8].

Biological context of arabino-2-Hexulosonic acid

• 2-Ketogluconate was transported against a concentration gradient, apparently in an unchanged state, and the process required metabolic energy, all of which indicate an active transport system [9].
• 2-Ketogluconate uptake obeyed saturation kinetics (apparent Km in 2-ketogluconate-grown cells was 0.4 mM) [9].

Associations of arabino-2-Hexulosonic acid with other chemical compounds

• In addition to the ability of Penicillium notatum to grow on sucrose, glucose, fructose and gluconate, substantial growth occurred on 2-ketogluconate and 5-ketogluconate thereby indicating a diverse sugar metabolism [10].

Gene context of arabino-2-Hexulosonic acid

• This change was a consequence of decreased activities of glucose dehydrogenase and gluconate dehydrogenase and of the transport systems for gluconate and 2-oxogluconate, and an increased activity of glucose transport, while relatively high activities of hexokinase and glucose-6-phosphate dehydrogenase were maintained [11].

Analytical, diagnostic and therapeutic context of arabino-2-Hexulosonic acid

• Comparative cellulose thin-layer chromatography including 2-ketogluconate and 2,5-diketogluconate (produced by Janthinobacterium lividum) as standards, showed that gluconate was oxidized to 2-ketogluconate by S. marcescens and E. cypripedii, and 2-ketogluconate was oxidized to 2,5-diketogluconate by E. cypripedii [12].

References