Extraction of defatted soy-bean cotyledon meal, after prior removal of soluble sugars and protein, with ethylenediaminetetra-acetic acid disodium salt furnished a mixture of an arabinogalactan and an acidic polysaccharide complex. The arabinogalactan has been shown to contain chains of 1 -4 linked p-D-galactopyranose residues in which every fourth or fifth residue carries through C-3 a side-chain containing, on the average, two L-arabinofuranose residues joined by a 1 __+ 5 linkage. The acidic polysaccharide complex has been shown to possess a highly branched structure with residues of galacturonic acid, galactose, arabinose, xylose, fucose, and rhamnose in which side-chains are terminated by galactopyranose, fucopyranose, xylopyranose, and arabinofuranose residues.KAWAMURA and his collaborators24 have shown that soy-bean cotyledons contain complex mixtures of polysaccharides which give on hydrolysis galacturonic acid , galactose, arabinose, xylose, fucose, and rhamnose, but knowledge of the structures of the soy-bean polysaccharides has been restricted to some of the constituents of the h u l l s . l ~~-~ In continuation of our studies of the structures of the polysaccharide components of soy-beans 137 we describe here the extraction and fractionation of polysaccharides from the cotyledons, the characterisation of an arabinogalactan, and the preliminary examination of an acidic polysaccharide complex.Defatted soy-bean cotyledon meal was extracted with boiling ethanol-water (4 : 1) to remove soluble sugars and to inactivate enzymes, and then with cold 0.2% sodium hydroxide, according to the procedure

The inclusion of raw kidney beans (Phaseolus vulgaris cv. Processor) in diets of growing pigs resulted in loss of appetite, growth depression and intermittent scouring. Immunocytochemical and morphological investigations showed extensive disruption of intestinal microvilli in those areas of the small intestine where dietary bean lectins were bound to the mucosal surfaces. Degenerative changes were also present in pancreatic acinar cells of pigs fed on kidney beans. These changes were not a direct effect of the bean lectins but may have been related to the disturbances in the gut.

The complete amino acid sequence of the major a subunit of the lectin from seeds of Dioclea grandzflora was determined. The sequence was deduced from analysis of peptides derived from the native a subunit by digestion with trypsin, chymotrypsin, the Staphylococcus aureus V8 protease, and pepsin; and from larger peptides produced by digestion of the citraconylated protein with trypsin. The a subunit consists of a single polypeptide chain of 237 amino acids which differs from the sequence of concanavalin in 53 positions. Significant levels of heterogeneity were observed in five positions in the sequence.Seeds of Dioclea grandiflora (mucang), an interesting and potentially valuable legume seed from the North East of Brazil, contain a number of closely related lectins which have been characterized recently [I] and shown to belong to the general group of D-mannose@-glucose)-binding lectins [2]. It was also shown that the D. grandzjlora lectins were similar to the wellcharacterized concanavalin A from Canavalia ensiformis in that they had a requirement for the presence of Ca2+ and Mn2+, lacked covalently bound carbohydrate, and had a similar amino acid composition, molecular mass and subunit structure, but differed distinctly in having high PI values in the region of pH 8.6 -9.0. Like concanavalin A the lectins from D. grandiflora could be dissociated in the presence of SDS to yield three subunits a, j, and y of approximate relative molecular mass 25 -26 000, 13 -14000 and 8 -9000 when examined by SDS-PAGE. The full molecule at neutral pH values appeared to have the composition of a,j,y, but at low pH values it seemed likely that this was split symmetrically into two half-molecules of apy.Whilst the amino acid sequences of several lectins belonging to the tribe Vicieae have been determined [3 -101 until now the only primary structure known for a lectin from the tribe Diocleae is that for concanavalin A [l 1 -121. We now wish to report the complete sequence of another lectin from this tribe, the major a subunit of the lectin from D. grandiflora which although it shows close similarity with the concanavalin A sequence nevertheless differs in 53 amino acid positions. MATERIALS AND METHODSDioclea grandiflora (Mart) seeds were collected in the state of Ceara, Brazil. The initial purification of the lectin was as Abbreviations. SDS, sodium dodecylsulphate ; PAGE, polyacrylamide gel electrophoresis; HPLC, high pressure liquid chromatography; dansyl, 5-dimethylamino-naphthalene-l-sulphonyl ; DABITC, 4-N, N-dime thylaminoazobenzene-4'-iso thiocyanate.Enzymes. grandzflora lectin were dissolved in 1 ml of 3 % SDS, heated at 100 "C for 10 min and applied to the column, which was eluted at a flow rate of 8 ml/h. The size of the fractions collected was 1.2 ml. The intact a subunit emerged from the column at 1.71 x void volume, whilst the j and y subunits were eluted together at 1.99 x void volume. After one re-chromatographic step the a subunit contained only one component when examined by SDS-PAGE (with an apparent M , of 25 -26 ...

The degradation of filter paper by the anaerobic fungus Neocallimastix frontalis strain RE1 was reduced by the addition of cell-free supernates from cultures of Ruminococcus albus strain J6 and R. flavefaciens strains 17 and 007. Fungal uptake of, and growth on, glucose was not affected. After gel permeation and anion exchange chromatography, inhibitory activity towards fungal cellulolysis was recovered in a fraction from strain 17 that contained at least five negatively charged polypeptide components, molecular mass 45-68 kDa, on SDS-PAGE.

A method is described for the sub-cellular ractionation of cotyledons from non-germinated Phaseolus vulgaris seeds in non-aqueous density gradients of potassium iodide in glycerol. The major organelles (protein bodies, cell walls and starch grains) are well resolved as adjudged by morphology and protein subunit patterns of gradient zones and are remarkably stable if water is rigorously excluded. The flexibility of the system is exploited in establishing the cytoplasmic location of the oligosaccharide fraction and in the large-scale preparative isolation of the sub-cellular components. The composition and morphology of the sub-cellular components are described and discussed.