1. The digestive juice of the snail Helix pomatia was used in the study of the degradation of isolated cell-wall preparations from a strain of Saccharomyces carlsbergensis. 2. The crude enzyme system was fractionated by gel filtration and the activities of the more specific fractions thus obtained were examined. 3. Results are discussed with respect to (a) the nature of various factors that are essential for protoplast formation and cell-wall dissolution and (b) structures envisaged in yeast cell walls that are responsible for the observed variations in susceptibility to attack by snail juice.

2. The carbon dioxide ratio, i.e. the ratio of the specific activities of expired carbon dioxide during the infusion of [1-14C]acetate and [2-14C]acetate, respectively, was 1-58 ± 0-17 (3) for non-pregnant sheep, 1-66 ± 0-25 (4) for sheep in early pregnancy, 1-74 + 0-14 (4) for sheep in late pregnancy, and 1-18 ± 0-11 (3) for under-fed sheep in late pregnancy. Calculations based on the last two ratios indicate that citric acid-cycle turnover in under-fed pregnant sheep is about one-quarter of the turnover found in well-fed pregnant sheep.3. The output of carbon dioxide is similar in all four groups of animals, but the percentage of carbon dioxide derived from acetate is low in the poorly-fed sheep in late pregnancy. The amount of acetate converted into carbon dioxide is lower in these animals but, because total aceta.te utilization is low in this group, the acetate presented to the tissues is oxidized as readily as in the sheep of other groups.

No abstract

A material containing both carbohydrate and protein together with some ferulic acid, and which has pronounced foam-stabilizing activity, has been isolated from beer. A fraction similar in constitution and activity to the beer constituent has been recovered from an aqueous extract of barley flour. These materials are comparable with a glycoprotein present in wheat flour; the latter has been shown to be effective in the stabilization of beer foam. There was little difference in the amount and activity of extracts prepared from different varieties of barley.

Recent investigations (reviewed by Gottschalk, 1958) have shown that the enzymic hydrolysis of a glycosidic linkage in an oligosaccharide is, in fact, a transglycosylation reaction in which a glycosyl group is transferred from the substrate to a water molecule. The latter thus acts as a glycosyl acceptor: