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ADP-Glucose pyrophosphorylase from Chlorella pyrenoidosa has been partially purified and its properties have been investigated. The enzyme activity was activated about 20-fold by 3-phosphoglyceric acid, the first product of the photosynthetic reduction cycle. The enzyme appears to be separate and distinct from UDP-glucose pyrophosphorylase, which was not activated by 3-phosphoglycerate. ADP-Glucose and ATP gave sigmoid-shaped rate versus concentration curves in the presence or absence of 3-phosphoglycerate. The V max of pyrophosphorolysis and synthesis of ADP-glucose was increased 7-fold and 18-fold respectively by 3-phosphoglycerate, and the K values of ADP-glucose and ATP were decreased 1.6-fold in the presence of the activator. Inorganic phosphate and ADP were inhibitors of the enzyme. The K i for phosphate and ADP were 2 × 10 −4 m and 2.5 × 10 −3 m , respectively. The inhibition by phosphate can be reversed by high concentrations of the activator, 3-phosphoglycerate. However, only partial reversal of ADP inhibition occurred with high concentrations of 3-phosphoglycerate. The significance of 3-phosphoglycerate activation and inhibition by phosphate and ADP in the regulation of starch biosynthesis in Chlorella was discussed.

A semiempirical relationship between the critical constants and the chain length of saturated hydrocarbons has been established.

Heats of fusion of p‐nitrotoluene, p‐toluidine, benzophenone, diphenylamine, 1:1 benzophenone—diphenylamine complex, and 1:2 urea—phenol complex have been determined with the help of a thermistor calorimeter.

During the last decade the electrocoating process has gained increasingly greater importance in the application of industrial paints. More recently, considerable interest has developed in an electrocoating system for white single coats requiring either a lower baking temperature or a shorter baking cycle. At present, most of the existing saturated anionic resin systems require a baking temperature of 150°C. or higher for a period of 15 to 30 minutes. The advantages of a lower baking temperature or shorter baking cycle are as follows: a. Faster line speed resulting in a higher production rate. b. Coating of an assembled article with plastic parts. c. Coating of temperature-sensitive metals. d. Lower consumption of energy.

Study of L-Proline Complexes of Bivalent Metal Ions&nbsp

The chronic stimulation of peripheral nerves has, in the past, usually been of an intermittent or relatively short-term nature. Histologic changes which have taken place have been attributed to the trauma caused by mechanical factors and/or the effects of electrical charges. Investigators, speculating on the effects of electro-stimulation, have designed electrodes specifically to minimize tissue damage. The purpose of the present investigation is to determine which pathologic alterations, if any, are caused specifically by electrical?as distinct from mechanical?factors. Dogs were divided into two groups, differing only in that one group?the controls?had electrodes implanted around the phrenic nerve, but stimulation was never applied. Duration of the test was up to 308 days. The results indicated that no histologic alterations could be attributed specifically to electrical stimulation, as contrasted to mechanical trauma, to the phrenic nerve.