Metabolism of Carbohydrates and Related Compounds

This year the Editorial B oa rd has divided the heroic task of reveiwing microbial metab olism into two pa rts ; this di vision simplifies the task of the reviewer to a considerable extent, but still leaves many aspects of a la rge area to be covered. This review has tried to cove r the j ou rnals received in the year 1955. Abstracts of pape rs deli ve red at meetings are n ot th oroughly re viewed since they a re al ready a vailable in concentrated form , but many have been included if they seemed to fit into a subject being devel oped. Numerous reviews and symp osia appea r each year on aspects of the metabolism of microorganisms, and the subject has been reviewed each yea r in this series, so the m ain role of the Annual Review appears t o be that of asse mbling the publicati ons of the year with some indication of the status of the sub ject. The va riety of papers reported on should indicate the in­ ability of a single re viewer to comment adequately on their significance and relati onships. The yea r has seen the publication of many of the experimental details which pertain to the study of the enzymes and enzyme systems concerned with the vari ous pathways of carb ohyd rate metabolism ab out which so much has been said at meetings and symposia. The assessment of the role of these pathways in the metabolism of va ri ous microorganisms has been the subject of many pape rs. The t rica rb oxylic acid cycle continues to p ro­ voke experiment and comment. The va riety of microorganisms, growth conditi ons , and substrates make plain the am ount of w ork that remains t o b e d one. The fol lowing re views have appea red : "Mechanism of action and p rop­ e rties of pyridine nucle otide-linked enzymes " by Racke r (1), "Significance of alte rnate pathways in the metabolism of glucose " by Wood (2), "The