No abstract

No abstract

Films prepared from a deformable gel (or putty) of hyaluronic acid show high crystallinity and orientation in their x-ray diffraction patterns. We have derived a probable structure for the molecules in these films. This is a double helix in which two identical, left-handed strands are antiparallel to one another. Each strand has four disaccharide residues per pitch length. Although the putty is prepared at pH 2.5, at which dilute solutions of hyaluronic have exaggerated rheological properties, the double helical form can also exist at physiological pH and therefore may be a biologically important form.

1. Pyruvate is the major product of malate oxidation by isolated cauliflower bud mitochondria when pyruvate dehydrogenase is inhibited. Pyruvate formation, which requires Mg++, Mn++ or Go++, is stimulated by added NAD.2. The effects of ADP, 2,4-dinitrophenol and respiratory inhibitors on pyruvate formation indicate that the reaction is linked to mitochondrial electron transport.3. No enzymic decarboxylation of oxaloacetate to pyruvate by the mitochondria can be observed. With added malate oxaloacetate breaks down in the mitochondria, probably to malate using NADH generated by a mitochondrial malic enzyme. 4.

No abstract