Bioconversion of glucose and fructose to sorbitol and gluconic acid by untreated cells of Zymomonas mobilis.

The bioconversion of glucose and fructose to gluconic acid and sorbitol, respectively, by the enzymes glucose-fructose oxidoreductase (GFOR) and glucono-delta-lactonase (GL), contained in untreated cells of Zymomonas mobilis ATCC 29191, was investigated in batch runs with glucose plus fructose concentrations (S0) varying from 100 to 750 g l-1 in equimolar ratio. When S0 was increased to 650 g l-1, the yields were improved, reaching a maximum of 91% for both products, with productivities of 1.6 and 1.5 g g-1 cell h-1 for gluconic acid and sorbitol, respectively. Above this level (S0 = 750 g l-1), no further improvement in yields was observed and productivities decreased due to the longer process time. The high yields of bioconversion runs with S0 > or = 650 g l-1 are a consequence of the sequential inhibition of the normal metabolism of Z. mobilis by substrates and products, resulting in preferential utilization of substrates via the GFOR/GL system.

Insulin pump therapy in young children with type 1 diabetes.

Six 17- to 53-month-old diabetic children had marked metabolic instability characterized by chronic hyperglycemia and frequent or severe hypoglycemia with conventional management that included twice daily insulin injections, diet, and home blood glucose monitoring. Because of the metabolic instability, all were given continuous subcutaneous insulin infusions (CSII) via portable externally worn infusion pump. During 6 months of CSII, there was marked improvement: hemoglobin A1 decreased from 192% +/- 8% (SD) to 152% +/- 31% of the normal mean (P less than 0.02), and hypoglycemic episodes decreased in both severity and frequency. CSII was incorporated into the children's treatment with no appreciable adverse psychologic effects or interference with normal activities. CSII, under carefully controlled clinical conditions, may be of benefit in some preschool children with unacceptable metabolic control of diabetes mellitus.