Konjac mannan consumed 0.991 moles of sodium metaperiodate per anhydrohexose residue. The Smith degradation of this glucomannan produced large amounts of glycolaldehyde and erythritol, in addition to small amounts of D-mannose, D-glucose and glycerol. Complete acid-hydrolysis of the glucomannan yielded n-mannose and D-glucose in a molar ratio of 1.6:1.00 or 8:5. The hydrolysate of konjac glucomannan by β-mannanase preparation from konjac tubers yielded a mixture of oligosaccharide, from which the following compounds were isolated and identified: (1) M→M, (2) G→M, (3) G→G, (4) M→M→M, (5) G→M→M, (6) M→G→M, (7) G→G→M, (8) M→M→M→M, (9) G→M→M→M, (10) G→M→M→G, (11) G→G→M→M, (12) M→M→M→M→M, (13) G→M→M→M→M. On the basis of the above results, the possible structures of this glucomannan and the specificities of β-mannanase were discussed.

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Two components of konjac β-mannanases, I and II, were purified by Amberlite CG-50 column chromatography and Sephadex G-100 and G-50 column chromatography. The enzyme preparations behaved as a homogeneous protein in ultracentrifugal analysis. Their molecular weights were estimated to be 32, 000 and 29, 000, respectively, by gelfiltration method.
Kinetic studies of these β-mannanases indicated that the hydrolysis of konjac glucomannan, mannooligosaccharides and glucomannooligosaccharides proceeds in a random or an endowise mechanism, but the randomness of enzyme I is less than that of enzyme II.
Both β-mannanase I and II hydrolyzed β-1, 4-mannooligosaccharides and glucomannooligosaccharides, but the mannosidic bonds linked to the glucose residues were attacked slightly easier than thoe between mannose residues.
On the present and the previous results, a possible structure of the konjac glucomannan was proposed.

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Pectin lyase from the culture medium of Aspergillus japonicus was purified 122-fold by ammonium sulfate fractionation, Sephadex G-75 gel filtration, DEAF-Sephadex treatment, SE-Sephadex column chromatography, and Sephadex G-100 gel filtration. The purified enzyme was free from pectinesterase and endo-polygalacturonase, and was homogeneous on ultracentrifugal analysis. The isoelectric point and the sedimentation coefficient of the enzyme were at pH 7.7 and 3.4 S, respectively. Molecular weight of the enzyme by using gel filtration was estimated to be 32, 000. The pH optimum of the enzyme for pectin was 6.0, but was 7.0 for polymethyl polygalacturonate methyl glycoside. The addition of calcium ion stimulated the activity and shifted the pH optimum to 7.0, only when pectin was used as substrate. A marked inhibition of the activity was observed by oxidizing reagents such as iodine and N-bromosuccinimide, although hydrogen peroxide did not inhibit the activity. Metal chelating reagents, reducing reagents and sulfhydryl inhibitors did not affect the activity. The purified enzyme was able to macerate parenchymateous tissues, in which onion tissue was the most susceptible one to be attacked by the enzyme.

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Anthranilate synthetase from Corynebacterium glutamicum ATCC 13032 was studied using the dialyzed cell-free extract. The reaction mechanism of the enzyme was found to be of ping-pong type. The Km values for chorismate and L-glutamine were 4.8×10^-5M and 5.9×10^-3M, respectively. Enzyme activity was strongly inhibited by L-tryptophan competitively with respect to chorismate and noncompetitively with respect to L-glutamine. This competitive inhibition of anthranilate synthetase activity by L-tryptophan means that the enzyme reaction would proceed in the condition under which sufficient amount of chorismate is supplied and explains rationally the excretion of L-tryptophan and anthranilate by a phenylalanine and tyrosine double auxotroph of C. glutamicum, KY 9456, in the medium supplemented with limiting amounts of L-phenylalanine and L-tyrosine. Formation of anthranilate synthetase in C. glutamicum KY 9285, a tryptophan auxotroph, was sensitive to the repression by L-tryptophan.

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Regulatory properties of chorismate mutase from Corynebacterium glutamicum were studied using the dialyzed cell-free extract. The enzyme activity was strongly feedback inhibited by L-phenylalanine (90% inhibition at 0.1_??_1mM) and almost completely by a pair of L-tyrosine and L-phenylalanine (each at 0.1_??_1mM). The enzyme from phenylalanine auxotrophs was scarcely inhibited by L-tyrosine alone but the enzyme from a wild-type strain or a tyrosine auxotroph was weakly inhibited by L-tyrosine alone (40_??_50% inhibition, L-tyrosine at 1mM). The enzyme activity was stimulated by L-tryptophan and the inhibition by L-phenylalanine alone or in the simultaneous presence of L-tyrosine was reversed by L-tryptophan. The Km value of the reaction for chorismate was 2.9×10^-3M. Formation of chorismate mutase was repressed by L-phenylalanine. A phenylalanine auxotrophic L-tyrosine producer, C. glutamicum 98-Tx-71, which is resistant to 3-aminotyrosine, p-aminophenylanaine, p-fluorophenylalanine and tyrosine hydroxamate had chorismate mutase derepressed to two-fold level of the parent KY 10233. The enzyme in C. glutamicum seems to have two physiological roles; one is the control of the metabolic flow to L-phenylalanine and L-tyrosine biosynthesis and the other is the balanced partition of chorismate between L-phenylalanine-L-tyrosine biosynthesis and L-tryptophan biosynthesis.

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Mutants producing a large amount of L-tryptophan were derived from a phenylalanine and tyrosine double auxotroph of Corynebacterium glutamicum, KY 9456 which produced only a trace amount of L-tryptophan (150 μg/ml) and anthranilate. A mutant, 4 MT-11, resistant to 5-methyltryptophan, tryptophanhydroxamate, 6-fluorotryptophan and 4-methyltryptophan which was derived by stepwise mutagenic treatments produced L-tryptophan at a concentration of 4.9mg/ml in a molasses medium containing 10% of sugar calculated as glucose. L-Tryptophan production with 4 MT-11 was inhibited by L-phenylalanine and L-tyrosine. Accordingly, mutants resistant to phenylalanine and tyrosine analogs such as p-fluorophenylalanine, p-aminophenylalanine, tyrosinehydroxamate, and phenylalaninehydroxate were derived from 4 MT-11. One of the mutants, thus obtained, Px-115-97 produced L-tryptophan at a concentration of 12.0mg/ml in the molasses medium. L-Tryptophan production with the mutant was still sensitive to L-phenylalanine and L-tyrosine.

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Regulatory properties of the enzymes involved in aromatic amino acid biosynthesis in the mutant of Corynebacterium glutamicum which produces a large amount of aromatic amino acids were examined. A phenylalanine auxotrophic L-tyrosine producer, pr-20, had a 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP) synthetase released from the feedback inhibition by L-phenylalanine, L-tyrosine and L-tryptophan and had a two-fold derepressed chorismate mutase. A pair of L-phenylalanine and L-tyrosine still strongly inhibited the chorismate mutase activity, though the enzyme was partially released from the inhibition by L-phenylalanine alone. A tyrosine auxotrophic L-phenylalanine producer, PFP-19-31, had a DAHP synthetase sensitive to the feedback inhibition by L-phenylalanine, L-tyrosine and L-tryptophan and had a prephenate dehydratase and a chorismate mutase both partially released from the feedback inhibition by L-phenylalanine. The mutant produced a large amount of prephenate as well as L-phenylalanine. A phenylalanine and tyrosine double auxotrophic L-tryptophan producer, Px-115-97, had an anthranilate synthetase partially released from the feedback inhibition by L-tryptophan and had a DAHP synthetase sensitive to the feedback inhibition. These data explained the mechanism of the production of aromatic amino acids by these mutants and supported the in vivo functioning of the control mechanisms of aromatic amino acid biosynthesis in C. glutamicum previously elucidated in vitro experiments.

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Taxonomical investigation was performed on the bacterium, strain NB 320 isolated from soil, and it was identified as Enterobacter cloacae. This bacterium produced the enzyme which catalyzed the transamination reaction between 3, 4-dihydroxyphenyl pyruvate and an amino acid to form L-Dopa.
The optimum culture conditions for the enzyme production were studied along with the characteristics of the enzyme. The enzyme of the strain was different in some properties from that of Alcaligenes faecalis IAM 1015 which had been already studied. The former utilized glutamate as an amino donor best among the amino acids tested for transamination and was induced by the addition of glutamine and asparagine. Intact cells of the strain did not catalyze the reaction unless they were treated with sonication or with a detergent.

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The fate of the nitrite during curing and cooking was investigated with the model solutions composed of myoglobin, sodium nitrite and sodium ascorbate at various ratios.
All nitrogen in nitrite, after curing and cooking, was recovered as residual nitrite (I), nitrate (II), nitrosyl group of denatured nitrosomyoglobin (III) and gaseous nitrogen compounds (IV). I, III and IV increased when the cooking temperature was raised from 70°C to 80°C. Almost all of the nitrite-N was recovered as II whenever greening occurred in the curing period. IV was produced under the condition where both sodium nitrite and sodium ascorbate were abundant as compared with myoglobin, and this reaction proceeded not in the curing period but at the cooking stage. The addition of sodium chloride into the model system increased I and III. A possible scheme of the fate of the added nitrite was discussed from the results obtained.

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1. A trial test was attempted of complete hydrolysis of peptides and proteins into amino acids by enzymes. “Neutral proteinase” of Bacillus subtilis or “Alkalophilic proteinase” of a Streptonzyces sp. was used for preliminary digestion of substrate, and a mixture of three aminopeptidases of Bacillus subtilis was employed for subsequent hydrolysis of proteinase digest.
2. The oxidized insulin B chain was hydrolyzed completely by the method. Several proteins including enzymes which contained no or less cystine and cysteine were also hydrolyzed almost completely.
3. On the other hand, certain glycoproteins were hydrolyzed to leave a few glycopeptides in which all glycomoieties of the proteins were retained. The implications of the results are discussed.

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The distribution of cysteine desulfhydrase activity was studied with crude extract from various bacteria. The enzyme activity was found in strains belonging to Enterobacteriaceae. A bacterial strain isolated from soil and identified as Aerobacter aerogenes I-3-2 had shown markedly high activity.
Cultural conditions for the formation of the enzyme were studied with this strain. L-Cysteine Or L-cystine, is essential as an inducer for the enzyme formation. Addition of glycerol at 0.1_??_0.2% concentration and CaCl₂•2H₂O at 0.2% promoted the enzyme formation. Cell extract with high enzyme activity was prepared from cells grown at 30°C for 8 hr in a medium containing 0.2% L-cysteine•HCl•H₂O, 0.1% glycerol, 0.2% CaC1_2••2H₂O, 0.3% yeast extract, 0.5% meat extract, 0.5% polypepton and 0, 2% NaCl in tap water with the pH 7.5.

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A new synthesis of (±)-9-demethylmunduserone (2) is described. Thermal rearrangement of 1-(4-benzyloxy-2-hydroxyphenyl)-4-(3', 4'-dimethoxyphenoxy)-2-butyn-l-one (7) afforded 4-(4-benzyloxy-2-hydroxybenzoyl)-6, 7-dimethoxy-2H-chromene (8), 3-(4-benzyloxy-2-hydroxybenzoyl)-5, 6-dimethoxy-2-methylbenzofuran (9) and 9-benzyloxy-2, 3-dimethoxy-6a, 12a-dihydrorotoxen-12 (6H)-one (3). 4-Aroyl-2H-chromene (8) was smoothly converted to 3 in quantitative yield by the treatment with sodium acetate. The structure of 3 was con-firmed by an alternative synthesis from methyl tephrosate (10). Debenzylation of 3 with aluminum bromide afforded (±)-9-demethylmunduserone (2) in high yield.

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Methyl linoleate (ML) and methyl linoleate hydroperoxides (MLHPO) were degradated by incubating under an aerobic condition at 37°C for a week. Identification of secondary degradation products (SP) by gas chromatography-mass spectrometry showed that the high proportions of hexanal, methyl octanoate and 8-formyl methyl octanoate (8-FMO) were found in degradated ML or MLHPO. In degradation of MLHPO, the decrease of peroxide value (POV) was slower than that of conjugated diene. In the earlier stage, POV was scarcely decreased, but in the later stage, MLHPO disappeared and another secondary hydroperoxides were produced. ML decreased linearly during 4-day incubation and the amount reached to 10% of the original one. The formation of 8-FMO was delayed to the increase of POV. Degradation process of autoxidized ML was discussed with the changes of POV, UV absorption and the amount of 8-FMO, and a formation mechanism of some SP was proposed.

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Three new compounds were isolated from Phyllosticta sp. and the structures were elucidated by spectroscopic data. Chemical conversion of epoxydon to these compounds confirmed the stereostructures to be 3, 4 and 5 respectively.

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The tetraketide origin of epoxydon I produced by Phyllosticta sp. is established by ¹³C NMR measurement on labelled epoxydons obtained from 1-¹³C- and 2-¹³C-acetate. The chlorinating mechanism of epoxydon to form non-enzymatically compound IV, V and VI was also confirmed by exposing epoxydon to the culture broth.

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Microbial alkaline protease inhibitor, S-SI, was immobilized by covalent binding with Sepharose (agarose spheres) which was previously activated by cyanogen bromide. S-SI- Sepharose, thus obtained, contained 7.2mg of S-SI in 1ml of settled volume, and its subtilisin-combining capacity was 16.6mg per ml. Stability of S-SI did not be lowered by immobilization. Affinity of immobilized S-SI for various proteases was examined, and it was revealed that α-chymotrypsin, as well as microbial alkaline proteases, had affinity for immobilized S-SI. To determine the most effective condition for dissociation of coupled subtilisin BPN', effects of pH, ionic strength, protein denaturants, and sodium dodecyl sulfate (SDS) were examined. Dissociated subtilisin BPN' with high specific activity was obtained when SDS was used as dissociating agent and was removed with Dowex 2-X10 column from dissociated enzyme solution. S-SI-Sepharose was applied to purifications of B. subtilis SO4 alkaline protease and α-chymotrypsin, and purified enzymes with high specific activity were obtained.

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The specificity of acid proteinase from a strain of Acrocylindrium was investigated using oxidized insulin A- and B-chains and glucagon. The enzyme was considerably specific for the bond involves carboxyl group of tyrosine, phenylalanine or leucine. The enzyme also seems to be considerably active when these amino acid donate amino group to the bond to be hydrolyzed.

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A colistin-like active substance was found in the cell extract of colistin-producing organism, Bacillus colistinus. This substance was designated colistin X and differed from known colistin on bioautograms and on gel filtration on Sephadex G-100 where it appeared in a protein fraction. Binding of ¹⁴C-labeled colistin with the cellular protein of the organism was noted in low colistin ratios, such as approximately 260 u/mg protein, by incorporating radioactivity into the protein fraction in gel filtration. The paper radiogram of the binding reaction mixture gave a radioactive spot corresponding to colistin X. In contrast, in high colistin ratios the cellular protein used was partially degraded by reaction with colistin.
From these results, it was assumed that the intracellular colistin X was a binding complex of colistin and cellular protein.

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Epimerization of (-) -isodihydrocarvone (I) to (-) -dihydrocarvone (II) by Pseudomonas fragi IFO 3458 was studied. I was easily epimerized to II by the growing cells, the resting cells or the cell-free extracts.
An epimerase catalyzing the conversion of I to II was partially purified from the bacterial extracts about 56-fold with heat-treatment, ammonium sulfate precipitation and DEAE-Sephadex A-50 column chromatography. By the action of this epimerase, the ratio of I to II becomes about 25:75 (K_??_3). It appeared that the epimerase is very stable to heat; the activity of epimerization remains 66 and 36% after treatment at 97°C for 60 and 120min, respectively.

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DL-(1245/36)^*2-1-Akkoxy (methoxy, ethoxy and 2, 2, 2-trifluoroethoxy)-2, 3, 4, 5, 6-pentach-lorocyclohexanes were synthesized from (1234/56)-1, 4, 5, 6-tetrachloro-2, 3-epoxycyclohexane (α-BTC cis-epoxide). Meso-(1245/36)-3-alkoxy (methoxy, ethoxy and 2, 2, 2-trifluoroethoxy)-1, 2, 4, 5, 6-pentachlorocyclohexanes were synthesized from (1245/36)-3, 4, 5, 6-tetrachlorocyclo-hexane-1, 2-diol (α-BTC cis-diol).
DL-(1245/36)-3, 4, 5, 6-Tetrachloro-1, 2-dimethoxycyclohexane and meso-(1245/36)-1, 2, 4, 5-tetrachloro-3, 6-dimethoxycyclohexane were also prepared.
Hexa-O-methyl-muco-inositol was synthesized by the methylation of muco-inositol (1245/36-configuration).

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DL-(1245/36)^*2-2, 3, 4, 5, 6-Pentachlorocyclohexanecarbonitrile was synthesized from (1234/56)-1, 4, 5, 6-tetrachloro-2, 3-epoxycyclohexane (α-BTC cis-epoxide). DL-(1245/36)-2, 3, 4, 5, 6-Pentachloro-1-methylcyclohexane was synthesized from the nitrile via DL-(1245/36)-2, 3, 4, 5, 6-pentachlorocyclohexylmethanol, the structure of which was confirmed by PMR spectroscopy using spin decoupling techniques and the shift reagent, Eu (DPM)₃. This series of compounds was shown to have the same configuration as γ-BHC. The conformational equilibrium of these compounds is discussed. DL-(1245/36)-2, 3, 5, 6-Tetrachloro-1, 4-dimethyl-cyclohexane was synthesized by a stepwise route involving a Diels-Alder reaction of trans, trans-hexadiene-2, 4 with maleic anhydride.

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Meso-(1245/36)^*2-1, 2, 4, 5, 6-pentachloro-3-methylthiocyclohexane, and (124/356)-1, 2, 4, 5, 6-pentachloro-3-methylthio and ethylthiocyclohexanes were prepared from (1234/56)-1, 4, 5, 6-tetrachloro-2, 3-epoxycyclohexane (α-BTC cis-epoxide).

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Formation of sclerotia in a strain of Sclerotinia libertiana Fuckel using Czapek-Dox agar medium was highest at pH 4.0_??_6.0 and at 22_??_25°C. The response was better under darkness than under light. However, when a potato-extract medium was used the optimum temperature range extended, and even at 15_??_27°C mature sclerotia formed. The addition of indole-3-acetic acid (IAA) to the Czapek-Dox medium containing riboflavine stimulated the formation of sclerotia under fluorescent light. Though iodoacetic acid, a -SH reagent, also had a stimulatory effect, cysteine had little inhibitory effect on sclerotial formation. Formation was markedly inhibited by p-aminobenzoic acid (PABA), especially in the presence of tyrosine or tryptophan, and excess ammonium salts in the medium also produced an inhibitory effect. It was assumed that accumulation of an intermediary metabolite with high reactivity with -SH groups was necessary for sclerotial formation, but PABA and excess ammonium salts inhibited the accumulation.

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We have prepared a series of N-TFA-glycyl and N-TFA-L-prolyl dipeptide methyl ester from the corresponding dipeptide methyl esters by treating them with (TFA-Gly)₂O and TFA-L-Pro-Cl, respectively. Separation of these tripeptide derivatives by G. L. C. was studied and a relationship between the amino acid compositions of the tripeptides and their q_i-values (relative retention values) was observed, analogous to the case of the dipeptides previously reported.²⁾

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Some physicochemical properties and substrate specificity of acid protease B isolated from Scytalidium lignicolum were investigated.
The molecular weight determined by the sedimentation equilibrium and sedimentation velocity method was 21, 000 and 19, 000_??_20, 000, respectively. The isoelectric point was determined as 3.0 using the Tiselius electrophoresis apparatus, 3.2 by isoelectric focusing, respectively.
The enzyme did not contain histidine and was composed of 188 amino acid residues.
Substrate specificity against various synthetic peptides was different from those of the acid proteases which were inactivated by S-PI and DAN.

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In order to obtain a basic information of plant cell suspension culture as a step toward the development of large scale culture, culture conditions of crown gall cells (auxin nonrequiring cells) were investigated. Addition of yeast extract to culture medium was significantly effective for the growth and cell dispersion.
In experiments on the ability of the cultured cells to utilize sugars as the carbon source, it was observed that galactose, added to the culture medium, markedly inhibited the cell growth.
Pasteurization of the medium containing fructose as carbon source made it brownish by Maillard reaction and the medium apparently restrained the cell growth. However, the fructose medium sterilized by filtration was excellent for the cell growth as well as sucrose or glucose medium. In a jar fermentor, even the glucose medium became brownish by heat sterilization and the brown colored medium restrained the cell growth. Under optimum conditions, the doubling time was 1.1 day in exponential phase and 2.0g of cell (dry weight) per 100ml culture was obtained as the maximum yield.

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β-Galactosidase from Aspergillus oryzae was immobilized in crosslinked polyacrylamide gel beads. The presence of the enzyme inhibitor, such as glucono-δ-lactone or galactonoy-lactone, during polymerization procedure enhanced the residual enzymatic activity in the polymer beads, and activity yield attained up to 45%. Such enhancement effect was also observed when bovine serum albumin, dithiothreitol or glutathione was added during polymerization. Temperature and pH optima were not affected by the immobilization. The Michaelis constants for free and immobilized β-galactosidase were comparable. Lyophilized beads exhibited good stability without loss of enzymatic activity when stored at 4°C for 47 days.

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Two aminopeptidases, I and II, were found in the acidic fraction of the yeast autolysate, adsorbed on DEAE-cellose and DEAE-Sephadex A-50. Aminopeptidase I was purified as a single protein with a molecular weight of 200, 000. The enzyme required Zn for its activity and hydrolyzed dipeptides, and a polypeptide (glucagon). It also hydrolyzed amides, naphthylamides and the p-nitroanilide of amino acids. The enzyme was strongly inhibited by sulfhydryl reagents. Aminopeptidase II seemed also to be a metal enzyme with a molecular weight of 34, 000. The enzyme hydrolyzed the dipeptide and tetrapeptide but not leucine p-nitroanilide.

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In order to clarify the nutritional significance of metabolism of the carbon skeleton of individual amino acids, the metabolic fates of L-leucine-U-¹⁴C and L-alanine-U-¹⁴C were investigated in growing rats fed the diets with various protein calories percents (PC%) at 410 kcal of metabolizable energy.
The incorporation of ¹⁴C into body protein in 12hr after the injection of leucine-¹⁴C was about 73% of the dose in the 0 and 5 PC% groups, though it decreased with increasing the levels of dietary protein from 10 to 30 PC%. The value of ¹⁴C recovery in body protein almost agreed with the net protein utilization (NPU) determined for the whole egg protein in a similar experimental condition. The ¹⁴C recovery in expired CO₂ and body lipid suggested that the carbon skeleton of leucine is well utilized as an energy source when the dietary carbohydrate is extensively replaced by protein.
While, the incorporation of ¹⁴C into body protein from alanine-¹⁴C was less than about 11% of the dose in all the dietary groups, and the majority of ¹⁴C was recovered in expired CO₂ and body lipid in a remarked contrast to leucine.
A similar pattern in urinary excretion of ¹⁴C was obtained for these amino acids, and the refracted rise of ¹⁴C from 10 PC% may give an indication for minimum protein requirements.

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Feces protein particles (FPP), spherical or oval in shape, 1.0_??_3.5 μ in diameter, which were observed in the fresh feces of the Japanese, in an average density of 5×10⁹/g, resembled the rice protein bodies (RPB) in electron-microscopical fine structure. The FPP decreased in the feces of the man who had been given a rice-free diet consisting of steamed sweet potato; when boiled rice had been fed, the FPP increased, and reached the level of the original density within 5 days. The FPP were concluded to be derived from an indigestible fraction of the RPB which were supplied to the Japanese with the daily intake of rice.

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The synthesis of novel acetylenic ketone compounds and anti-inflammatory and antimicrobial activeties are herein described.

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An alternative synthesis of (±) -tubaic acid (I), a Key intermediate compound of rotenone synthesis, has been accomplished by the Wittig reaction.

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Conjugates of α_s1, κ-caseins and α_s1-κ-casein complex were prepared with dimethyl-aminonaphthalenesulfonate and pyrenebutyrate. Their fluorescence lifetimes and the rotational relaxation times were measured by single photon counting technique and
fluorescence depolarization technique, respectively. Both dimethylaminonaphthalenesul-fonate and pyrenebutyrate conjugates had more than two lifetimes and the longer lifetime of pyrenebutyrate conjugates was near 140 nsec.
The rotational relaxation time of pyrenebutyrate α_s1-κ-casein complex was smaller than that of pyrenebutyrate κ-casein polymer, which suggested that the complex formation of
α_s1- and κ-casein polymers led to dissociation of the κ-casein polymer.
Changes of the rotational relaxation time as a function of weight ratio of α_s1- and κ-casein polymers (α_s1/κ) showed the specific variation and it was suggested that 4 moles of α_s1-κ-casein complex were formed from one mole of κ-casein polymer.

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The ovomucin-lysozyme aggregation was remarkably affected by pH or ionic strength. The extent of interaction of F-ovomucin with lysozyme was much larger than that of S-ovomucin. The ovomucin-lysozyme interaction decreased correspondingly, at a rate depending on the time at which ovomucin was modified by neuraminidase. On the other hand, the ovomucin-lysozyme interaction disappeared completely by acetylation, succinila-tion, or carbamylation of lysyl ε-amino groups in lysozyme, but it was not greatly affected by guanidination of lysyl ε-amino groups in lysozyme. From these results, it was confirmed that the electrostatic interaction between the negative charges of the terminal sialic acid in ovomucin and the positive charges of lysyl ε-amino groups in lysozyme is essential for the ovomucin-lysozyme interaction.

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