Glycine-serine transformation in the photosynthetic bacterium Chromatium vinosum

The metabolic transformation of glycine into serine in the photosyntheticbacterium Chromatium vinosum was accompanied by the evolutionof CO₂ due to decarboxylation of glycine. Isonicotinylhydrazideinhibited both ¹⁴CO₂ evolution and the formation of ¹⁴C-serinefrom ¹⁴C-glycine. The results indicate that a glycine-serinetransformation reaction takes place which is analogous to thatoccurring in green leaf tissues. Glycine may be metabolisedthrough serine by this reaction. The light stimulation of ¹⁴CO₂evolution and ¹⁴C-serine formation from 14C-glycine by the Chromatiumcells are judged to be results of the light-induced enhancementof ¹⁴C-glycine uptake by the bacterial cells. ¹This is paper 53 in the series "Structure and Function of ChloroplastProteins" and paper 7 of the series "Biosynthetic Mechanismof Glycolate in Chromatium". Paper 6 of the latter series isRef. 3 by Asami and Akazawa (1978). ²This study was aided by research grants from the Ministry ofEducation, Science and Culture of Japan and the Nissan ScienceFoundation (Tokyo). ³Postdoctoral Fellow (1980) of the Japan Society for the Promotionof Science. (Received May 20, 1980; )     

Energy and Electron Transfer Systems of Chlamydomonas reinhardi. I. Photosynthetic and Respiratory Cytochrome Systems of the Pale Green Mutant

The role of cytochromes in photosynthetic electron transfer system has been studied using the pale green mutant of Chlamydomonas reinhardi (ATCC 18302). The existence of cytochromes b₅₆₃ and f is confirmed, while no significant amount of ascorbate-reducible cytochrome b₅₅₉ is detected in this mutant. The presence of cytochrome c and a small amount of a-type cytochrome is determined in these cells.     

Synthetic studies on amino-α-glycosides of aminocyclitols. Synthesis of kanamycin analogues

A diastereoisomer of Kanamycin C has been synthesized by a modified Koenigs—Knorr reaction of 3,4,6-tri-O-acetyl-2-(2,4-dinitroanilino)-2-deoxy-α-D-glucopyranosyl bromide with 4-O-(3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-D-glucopyranosyl)-N,N′-di[(benzyloxy)carbonyl]-2-deoxystreptamine. Several Kanamycin analogues were synthesized by a similar condensation reaction. Each of the condensed products was isolated as its crystalline tetra-N-acetyl derivative and was proved by n.m.r. spectroscopy in D₂O to have the α-configuration.     

Evidence for the formation of methoxyl groups of ferulic and sinapic acids in Bambusa by the same O-methyltransferase

The two methylation reactions, i.e. caffeate to ferulate (FA) and 5-hydroxyferulate to sinapate (SA), in the biosynthesis of guaiacyl and syringyl lignins in angiosperms were demonstrated to be catalyzed by the same enzyme in bamboo. This follows from the facts that: the ratio (SA/FA) obtained for O-methyltransferase remains constant during purification of the enzyme; chromatography on DEAE-cellulose, Sephadex G100 and G200, and analyses by polyacrylamide gel electrophoresis and isoelectric focusing in pH gradients showed that the two methylating activities belonged to a single enzyme protein; caffeate and 5-hydroxyferulate compete each other in the formation of the enzyme-substrate complex, the latter substrate showing greater affinity for the enzyme. Thus, feedback control may operate at the methylation step, caffeate to FA, in biosynthesis of angiosperm lignin.