When crude culture fluid of an Arthrobacter bacterium was applied on to Avicel column equilibrated with 0.01M phosphate buffer, pH 6.8, lytic activity for isolated yeast cell wall adsorbed to the column and was eluted from the column by successive washing with the same buffer solution. Examination by disc electrophoresis revealed that the molecular species of β-1, 3 glucanase with high lytic activity for isolated yeast cell wall were the main protein components of the pooled active fractions. These molecular species adsorbed to Avicel column also in 0.01M succinate buffer, pH 5.6, but did not in 0.01M Tris chloride buffer, pH 8.5. The molecular species of β-1, 3 glucanase with low lytic activity for isolated yeast cell wall did not show any appreciable adsorption to Avicel column under the conditions tested. Two molecular species of β-1, 3 glucanase with high lytic activity for isolated yeast cell wall of a strain of Bacillus circulars adsorbed to Avicel column in 0.01M succinate buffer, pH 5.6 and in 0.01M phosphate buffer, pH 6.8, but did not adsorb to it appreciably in 0.01M Tris chloride buffer, pH 8.5. Chromatographic evidence was obtained which indicates the presence of a molecular species of glucanase which may be characterized as having low lytic activity for isolated yeast cell wall and which does not adsorb to Avicel in 0.01M phosphate buffer, pH 6.8 in crude culture fluid of this Bacillus bacterium. Such differential adsorption to Avicel of molecular species of β-1, 3 glucanase was also strongly suggested with the glucanase system of Zymolyase-5000.

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It was found that 2-hydroxy-3-phenylpropenoic acid, phenyllactic acid, phenylacetic acid and β-phenylethylalcohol were formed in the broth of Saccharomyces rouxii cultured with phenylalanine as substrate. 2-Hydroxy-3-phenylpropenoic acid (HPPA) was formed from phenylalanine (D- and L- form) via phenyllactic acid (n- and L- form) and degraded to phenylacetic acid.
On the other hand, β-phenylethylalcohol was formed from phenylalanine via β-phenylethylamine. Further degradation of phenylacetic acid and β-phenylethylalcohol was not observed in this experiment. From these results, a metabolic pathway of phenylalanine in Saccharoinyces rouxii was proposed.

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1. Screening of microorganisms which hydrolyzed L-α-amino-ε-caprolactam^** into L-lysine from soil was undertaken to establish an enzymatic method of L-lysine production. Several yeast strains were isolated which grew on L-aminolactam and whose cells hydrolyzed it into L-lysine.
2. A taxonomic study on the yeasts isolated was performed and they were classified into three genera and species, Cryptococcus laurentii, Candida humicola and Trichosporon cutaneum.
3. Authentic yeast strains obtained from some organizations were screened for the ability to utilize and hydrolyze L-aminolactam and the above three genera and species were found to possess the ability.

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Cells of Cryptococcus laurentii, which had been isolated from soil as microorganisms utilizing and hydrolyzing L-aminolactam, ^** catalyzed the asymmetrical and quantitative hydrolysis reaction of DL-aminolactam, used as a 10% aqueous solution at pH 9.0, producing L-lysine. A cell-free extract of the yeast cells was fractionated by ammonium sulfate and the active fraction was also used for the hydrolysis of L-aminolactam under variou_??_ conditions.

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The mycelia of a wild type strain of Neurospora crassa (6068, IFO) contain a polysaccharide which is stained reddish brown by iodine. The polysaccharide purified by repeated precipitation with ethanol is made up of D-glucose and has a molecular weight of about (more than) 2×10⁷, 101 S on ultracentrifugation analysis, an average chain length of 10, β-amylolysis limit of 33.6%, and α-amylolysis limit of 58.3%. The highly branched structure, therefore, resembles to that of a typical glycogen. The properties of the glycogen from N. crassa are discussed in comparison with the commercial glycogens from shellfish and rabbit liver.

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Dimethylol dimethylhydantoin (abbreviated as DMDMH), a water-soluble, stable, colorless and odorless hydantoin derivative, was investigated with various microorganisms for its potential applicability as an antiseptic agent. The possible mechanism of its action was elucidated. DMDMH inhibits bacterial and fungal growth at 15.6 to 250 μg/ml, and HeLa S 3 cells at 13.7 μg/ml by its continuous presence. Its removal after 1-hr incubation at 5, 000 μg/ml reversed the bacterial growth, thus indicating bacteriostatic action. The mechanism of action, in a study using a proton nuclear magnetic resonance, revealed a release of formaldehyde from DMDMH when pH was increased. Effect of DMDMH on antigenantibody reaction in agar gel showed no adverse effect at moderate concentration. Since its toxicity to animal was much less than that of mercurials or phenol, it can be useful as an antiseptic agent.

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Structural polypeptides of a soluble glycoprotein isolated from the delipidized bovine milk fat globule membrane were investigated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The soluble glycoprotein dissociated by SDS was found to be composed of at least eight polypeptides on SDS-polyacrylamide gel electrophoresis. Of the eight, seven were detected by periodic acid-Schiff staining for carbohydrate (PAS-I to VII) and three by coomassie blue staining for protein (CB-I to III). PAS-IV and V had the same mobilities as CB-I and II, respectively. PAS-I, II, III and VI, which were not detected by protein staining, were shown to be glycopeptides by proteolysis experiments. The apparent molecular weights were estimated to be ranging from 88, 000 to 10, 000 daltons on SDS-polyacrylamide gel electrophoresis with an increase in gel concentration.
The electrophoretic patterns and apparent molecular weights of these constituent polypeptides of the soluble glycoprotein were evidently different from those of the insoluble apoprotein fractions, which were dissociated into at least 13 coomassie blue positive bands and 7 periodic acid-Schiff positive bands.

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In order to make clear the mechanisms of association and precipitation of α_s1-casein by calcium ions, the interaction of phosphate and carboxyl groups of the protein with calcium ions was investigated by infrared spectroscopy, ultraviolet difference spectroscopy, ultracentrifugation, and circular dichroism. It was confirmed that the infrared absorption band at 980 and at 1400cm^-1 were due to -PO₃^2- and -COO^-, respectively. The band at 980cm^-1 shifted and that at 1400cm^-1 reduced by addition of calcium. Changes of calcium binding groups responsible for precipitation can be classified into three steps. In the first step (zero to 1mM CaCl₂), interaction of -PO₃^2- with calcium took place predominantly and chromophoric residues were buried to the inside of the molecule. In the second step (1 to 3mM CaCl₂), changes of -COO^- developed with decrease of those of -PO₃^2- and association of the casein began gradually. In the third step above 3mM CaCl₂, -COO^- further interacted with calcium and association of the protein increased rapidly. It is speculated that the roles of -PO₃^2- and -COO^- on the precipitation of α_s1-casein by calcium are to cause the conformational changes for the association.

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In order to study the formation of calcium cross-linkage of α^s1-casein, interaction of α^s1-casein with calcium was investigated in 4M urea.
Two types of calcium binding above and below 5mM Ca²⁺ were found from the analysis of calcium binding curve of α^s1-casein in 4M urea. Until 5mM Ca²⁺ where the first type of binding proceeded, increase of s_{20, w} took place. However, the α^s1-casein in 4M urea existed as a monomer even in the presence of 10mM Ca²⁺. Since partial specific volume and molecular weight of α^s1-casein did not change by calcium, the increase of s_{20, w} is considered to be due to the change of gross structure by the formation of intramolecular cross-linkage. This cross-linkage is expected to be formed in the absence of urea, and to play an important role in the formation of the aggregates.

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The following ten new analogs of neohesperidin dihydrochalcone (DHC) (I) were synthesized: Hesperetin DHC-4'-β-L-quinovopyranoside (XXVII), hesperetin DHC-4'-(α-L-quinovopyranosyl-(1→2)-β-D-glucoside) (XXVIII), hesperetin DHC-4'-(β-L-quinovopyranosyl-(1→2)-β-D-glucoside) (XXIX), hesperetin DHC-4'-(α-L-quinovopyranosyl-(1→2)-β-D-galactoside) (XXX), hesperetin DHC-4'-(β-L-quinovopyranosyl-(1→2)-β-D-galactoside) (XXXI), hesperetin DHC-4'-(α-L-rhamnopyranosyl-(1→2)-β-D-galactoside) (XXXII), hesperetin DHC-4'-(α-L-mannopyranosyl-(1→2)-β-D-glucotide) (XXXIII), hesperetin DHC-4'-(α-L-mannopyr-anosyl-(1→2)-β-D-galactoside) (XXXIV), hesperetin DHC-4'-(α-D-mannopyranosyl-(1→2)-β-D-glucoside) (XXXV), and hesperetin DHC-4'-(β-D-arabinopyranosyl-(1→2)-β-D-glucoside) (XXXVI).
The compounds XXVII, XXVIII, XXX and XXXII are 1.97, 3.4, 3.4 and 10.2 times sweeter than saccharin, respectively. From the organoleptic data, it was concluded that in the molecule I, methyl group and gauche conformation of vicinal glycol group at carbons 2 and 3 of L-rhamnose unit, and α1→2 linkage in rhamnosyl glucose are important requirements for the elicitation of intense sweet taste.

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The significant betaine aldehyde dehydrogenase activity was found in the cells of Pseudomonas aeruginosa A-16. The enzyme was inducibly formed and accumulated in the presence of choline, acetylcholine or betaine in the medium. The enzyme was purified approximately 620-fold with an overall recovery of 2.6% and proved to be homogeneous by ultracentrifugation. The molecular weight of the enzyme was determined as approximately 145, 000 by gel filtration method. The enzyme had an isoelectric point around pH 5.1. The enzyme was quite specific for its substrate, betaine aldehyde. Both NADP and NAD functioned as coenzyme. The estimated values of Km at pH 7.4 and 25°C were 3.8×10^-4M for betaine aldehyde, 8.9×10^-5M for NADP and 2.2×10^-4M for NAD.

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Fatty infiltration in the liver of rats fed a low egg albumin diet was apparently disappeared by substituting the protein source for the albumin reacted with oxidized lipids (the mixture of egg albumin-ethyl linoleate (2:1, w/w) was kept at RH 80.4% and at 50°C for 7 days and defatted). The present study deals with the mechanism causing such a phenomenon.
The decrease in the content of liver triglyceride (TG) due to feeding the reacted albumin was essentially disturbed by supplementing amino acids for lost ones accompanied by lipid oxidation.
Feeding the amino acid mixture simulating the reacted albumin showed the same response to the reacted protein.
Supplementation of basic amino acids damaged to the amino acid mixture simulating the reacted albumin increased the content of liver TG, while that of sulfur amino acids inclined to decrease liver TG.
These results indicate that the disappearance of fatty liver in rats fed the reacted albumin is almost entirely, but not exclusively, ascribed to the change in the amino acid pattern, particulary to the loss of the basic amino acids. However, since the plasma lipid levels did not respond similarly, participation of other factor (s) could not be excluded.

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Some monohydroxylated derivatives of solanesol were isolated from cured Burley tobacco and their structures were elucidated by chemical and spectrometric studies. One of them was shown to be 3, 7, 11, 15, 19, 23, 27, 31, 35-nonamethyl-2, 6, 10, 14, 18, 22, 26, 30, 33-hexatriacontanonaen-1, 35-diol and another to be 3, 7, 11, 15, 19, 23, 27, 31-octamethyl-35-methylen-2, 6, 10, 14, 18, 22, 26, 30-hexatriacontaoctaen-1, 34-diol. Evidence has also been presented to show the presence of other solanesol derivatives which have a hydroxylated internal isoprene residue.

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The ubiquinone (UQ) content of BY-2 cells on surface culture was examined to compare with that in suspension culture. The UQ content on surface culture was a little lower than that in suspension culture, but the pattern of the time-course of the UQ formation on surface culture was similar.
The changes of UQ content in BY-2 cells during autolysis were also examined. UQ in the cells subjected to autolysis was not rapidly metabolized nor excreted into the medium.
In order to obtain basic information for UQ formation by BY-2 cells in suspension culture, the cultural conditions, especially nutritional ones were investigated. Addition of 2, 4-D was remarkably effective on UQ formation and a higher UQ content was observed with a higher 2, 4-D concentration. Sucrose and glucose concentrations in the original medium were also influential factors. The UQ content tends to increase with the decrease of the sugar content. Precursors of UQ, amino acids, vitamins and organic acids were not effective on the UQ formation.

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The methanol-grown cells of Kloeckera sp. No. 2201 exhibit a markedly high catalase activity as compared with the glucose-grown and ethanol-grown cells. In this connection, specific organelles (“microbodies”) appear only in the methanol-grown cells. When the yeast cells harvested from a methanol medium (cells whose catalase activity had been enhanced to an appreciable extent: “partially induced cells”) were transferred into media containing glucose, ethanol or methanol as the sole carbon and energy source, further increase of catalase activity was mediated only by methanol. This induction of catalase activity was partially inhibited by cycloheximide at its high concentration, but chloramphenicol did not show any effect. Glucose inhibited strongly the induction by methanol, while galactose gave no effect. Electron microscopical observation revealed that the development of microbodies in the cells growing on methanol was hardly affected by cycloheximide. Disappearance of microbodies was observed electron microscopically after the methanol-grown cells (partially induced cells) were transferred to a methanol-glucose medium and cultivated for 8 hr. 3', 5'-Cyclic AMP or dibutyryl-3', 5'-cyclic AMP could not eliminate the inhibitory effect of glucose on the catalase induction. Addition of caffeine or theophylline did not promote the action of the cyclic nucleotides. 3-Amino-1, 2, 4-triazole inhibited only 40% of the hydrogen peroxide-decomposing activity in the cell homogenate of methanol-grown cells even at its concentration of as high as 10mM, while sodium azide inhibited the enzyme activity completely at the concentration of 1mM.

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X-Ray structure determination of a dibromo-derivative of MS-3, a glyoxalase I inhibitor produced by a mushroom, was carried out by the heavy atom method. A total of 2713 independent reflections were measured. The crystal belongs to space group P_??_ with the lattice constants, α=13.892 (7) and c=12.686 (7) Å. The observed density indicates that four structure units of C₂₁H₂₂O₇Br₂•1/2Na•2H₂O are contained in a cell. The refinement of the structural parameters was carried out to an R value of 0.077 by the block-diagonal least-squares method. The result confirmed the structure of MS-3 as that had been proposed on the basis of chemical studies.

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Neutral-cyclodextrin glycosyltransferase (EC 3. 2. 1. 19) of alkalophilic Bacillus sp. (ATCC 21783) was purified by starch adsorption, DEAE-cellulose chromatography and Sephadex G-150 gel filtration chromatography followed by preparative polyacrylamide gel electrophoresis. Molecular weight of the purified enzyme was 85, 000_??_88, 000 by SDS-disc gel electrophoresis. The enzyme was most active at pH 7 and 50°C, and stable up to 60°C at pH 7 and in the range of pH 6_??_8 at 60°C by 30min incubation. The apparent V_max and Km values for α- and β-cyclodextrin at a constant concentration of sucrose were 417, 70 μmoles glucose/min•mg protein and 10, 0.83mM, respectively. About 85_??_90% of amylose, 75_??_80% of potato starch, 65_??_70% of amylopectin, 55_??_60% of glycogen, 45_??_50% of amylopectin β-limit dextrin, 20_??_25% of maltotriose and 10_??_15% of maltose were converted to cyclodextrins with 0.5_??_1% (w/v) of each substrate.
Schardinger β-dextrin was preferentially produced from starch, and α- or γ-dextrin was gradually formed after prolonged incubation. After 20min incubation, about 0.4, 14 and 2.5% of α-, β- and γ-dextrin were formed from starch, respectively.

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The structure of a new hydroxy terpenoid acid, 6 (S)-isopropyl-3ξ-methyl-3ξ-hydroxy-9-oxo-4 E-decenoic acid (la), isolated from a solvent-extract of Turkish tobacco, was elucidated by the spectroscopic properties and chemical evidence. This compound was suggested to be derived from thunberganoid diterpenoids and be a precursor of two dienoic acids, 6 (S)-isopropyl-3-methyl-9-oxo-2 E, 4 E-decadienoic acid (3 a) and 6 (S)-isopropyl-3-methyl-9-oxo-2 Z, 4 E-decadienoic acid (4 a) in Turkish tobacco.

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AMP deaminase (EC 3. 5. 4. 6) is a key enzyme in the adenine nucleotide metabolism of human erythrocytes. ATP activates the enzyme, while 2, 3-bisphosphoglycerate inhibits it. Complexes of magnesium and these organic phosphate compounds are not effectors of AMP deaminase. The AMP deaminase activity in the physiological range of AMP was calculated from AMP-saturation curves which were drawn by measuring the activity under simulated intracellular conditions. Since human erythrocytes have a high level of AMP deaminase, the enzyme activity must be repressed to a low level, which accounts for the half-life of adenine nucleotides in the erythrocyte. Although it is evident from the experimental results that 2, 3-bisphosphoglycerate plays an important role in the repression of the activity of this enzyme, the in vivo rate of turnover of adenine nucleotides can not be explained by the inhibitory effect of 2, 3-bisphosphoglycerate alone.

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A neutral α-glucosidase was purified from pig serum by precipitation with ammonium sulfate, chromatographies on DEAE-cellulose and -Sephadex A-50, and gel filtration on Bio-Gel P-300 and Sephadex G-200. The purified enzyme was homogeneous in ultracentrifugal and disc electrophoretic analysis. The sedimentation coefficient (S_{20, w}) was calculated to be 10.7 S, and the isoelectric point, 4.0. The molecular weight was estimated to be approximately 2.7×10⁵ by thin-layer gel filtration and SDS-disc electrophoresis.
The enzyme exhibited also glucoamylase activity. The optimal pH was found to be in the pH range of 6.0 to 7.0 for maltose and soluble starch. The ratio of velocity of hydrolysis for maltose (Km, 0.72mg/ml), soluble starch (Km, 9.8mg/ml) and shellfish glycogen (Km, 55.6mg/ml) was calculated to be 100:110:5.15 in this order.

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The substrate specificity of a neutral α-glucosidase was investigated. The enzyme was active especially on malto-oligosaccharides, phenyl-α-maltoside and nigerose. The action on isomaltose and phenyl-α-glucoside was too weak. Isomalto-oligosaccharides made up of three or more glucose units were not attacked. The α-glucans, such as amylopectin, β-limit dextrin, glycogen and amylose besides soluble starch, also were hydrolyzed.
The ratio of velocity of hydrolysis for maltose, nigerose, phenyl-α-maltoside, maltotriose and maltotetraose was estimated to be 100:89:93:74:80 in this order. The extraporated Km values for maltose, nigerose, phenyl-α-maltoside, maltotriose and maltotetraose were 2.1mM, 20.0mM, 0.33mM, 0.28mM and 0.15 mM, respectively. The enzyme is considered to be essentially a neutral α-glucosidase with a preferential activity on malto-oligosaccharides.

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The variation of activities of several NADP-linked and NAD-linked dehydrogenases were studied during the aerobic growth of two species of hydrocarbon-utilizable Candida yeasts on different carbon and nitrogen sources. The level of NADP-linked isocitrate dehydrogenase in C. tropicalis and C. lipolytica growing on acetate was significantly higher than that in the yeasts growing on glucose. The glucose-grown cells of C. tropicalis showed a high activity of glucose-6-phosphate dehydrogenase as compared with the acetate-grown cells, while the enzyme level in C. lipolytica was low regardless of carbon sources used. The cells of both yeasts growing on n-alkane and oleic acid contained relatively low activity of NADP-linked isocitrate dehydrogenase. Presence of NH₄⁺ ion in the acetate medium increased the level of NADP-linked isocitrate dehydrogenase activity. These results suggest that different types of NADPH-generating systems operate alternatively in these yeasts depending upon carbon and nitrogen sources.

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Glucose-6-phosphate (G 6 P) dehydrogenase and 6-phosphogluconate (6 PG) dehydrogenase were partially purified about 53-fold and 47-fold, respectively, from the cell-free extract of glucose-grown Candida tropicalis by means of ammonium sulfate fractionation and DEAE-cellulose column chromatography. AMP acted as the competitive inhibitor against G 6 P and NADP in the G 6 P dehydrogenase reaction. This inhibition was remarkable at low concentrations of NADP, increasing the sigmoidicity of the NADP-saturation curve. On the other hand, 6 PG dehydrogenase was not affected by AMP. Fructose-1, 6-bisphosphate (FDP) and phosphoenolpyruvate (PEP) inhibited slightly G 6 P dehydrogenase. 6 PG dehydrogenase was also weakly inhibited by FDP. Apparent Km values of G 6 P dehydrogenase were calculated as 1.8×10^-4M for G 6 P and 3.1×10^-5M for NADP. Those of 6 PG dehydrogenase were 9.4×10^-5M for 6 PG and 2.8×10^-5M for NADP.

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The acidic and the basic subunits were shown to be present in equimolar amounts in the 11 S globulin molecule by the densitometric scanning of the SDS gel and the molecular weight consideration. The four acidic subunits (A₁, A₂, A₃ and A₄) were found to be present in the approximate molar ratio of 1:1:2:2. Four basic subunits separated and designated as B₁, B₂, B₃ and B₄ based on the relative mobilities in the acidic gel in 7M urea were found to be present in the approximate molar ratio of 1:1:2:2. The four basic subunits were fractionated in approximately same amounts into three different peaks, peak I (B₁ and B₂), peak II (B₃) and peak III (B₄) by CM-Sephadex C-50 column chromatography in the presence of 6M urea. Three kinds of intermediary subunits of 11 S globulin were fractionated with DEAE-Sephadex A-50 in the absence of reducing agents in 6M urea, and disulfide bonds appeared to participate in the binding between the acidic and the basic subunits in the molar ratio of 1:1 with the following combinations; A₁ and A₂ combined with B₃, A₃ with B1 and B₂, and A₄ with B₄. In view of the above results and molecular weight consideration, a new model of subunit structure was proposed for 11 S globulin.

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Two kinds of α-galactosidase-producing microorganisms, strain No. 31-2 and strain No. 7-5, have been isolated from soil and subjected to a determinative study. On the basis of the morphological and physiological characters, the strain No. 31-2 was identified to be belonged to genus Micrococcus and the strain No. 7-5 to genus Bacillus. The former strain, Micrococcus sp. No. 31-2 produced exclusively an intracellular α-galactosidase, and the latter one, Bacillus sp. No. 7-5, secreted the enzyme into culture medium. The cell growth and enzyme production of both strains were observed to reach the maximum under an alkaline culture condition. The intracellular α-galactosidase of Micrococcus sp. No. 31-2 was inducible by galactose, melibiose, and raffinose, while the a-galactosidase of Bacillus sp. No. 7-5 was produced constitutively.

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The properties of α-galactosidases of alkalophilic strains of Micrococcus sp. No. 31-2 and Bacillus sp. No. 7-5 were examined. The enzymes were partially purified by ion exchange and gel filtration chromatography. The enzymes had pH optima between 6.5 and 7.5. The enzyme of the Micrococcus strain was stable at pH 7.5_??_8.0; that of the Bacillus strain was stable at rather broad pH ranging 6.0 to 8.5. The enzymes were both unstable at temperature higher than 35°C. Metal ions such as Ag⁺, Hg²⁺, etc. caused complete loss of activity. The enzymes were also sensitive to sulfhydryl reagents. Among the substrates tested, the order of the hydrolysis rate by these enzymes was o-nitrophenyl-α-D-galactoside>melibiose>raffinose.

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The synthesis of Papthion® and papoxon, optically active at the α-carbon of the α-ethoxycarbonylbenzyl moiety, was described. The optical isomers of papthion and papoxon exhibited a marked selectivity in the toxicity and anticholinesterase activity, respectively. d-Papthion was more toxic to mosquitoes, rice stem borers, diamond back moths and mice than the l-isomer. In contrast, l-papthion was more toxic to houseflies, and less toxic to mice and other insects than the d-isomer. Selectivity in toxicity appears to be directly related to the selective inhibition in vitro of acetyicholinesterase by the optical isomers of papoxon.

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Examination of DEAE-cellulose chromatography clearly demonstrated the presence of the enzyme cleaving 2-methylisocitrate into pyruvate plus succinate in the methylcitric acid cycle. The enzyme differed from the usual isocitrate lyase of Candida lipolytica, and was herein given the trivial name of methylisocitrate lyase.
The chromatography also proved the mutant strain of C. lipolytica, producing 2-methylisocitrate from odd-carbon n-alkanes, to lack this methylisocitrate lyase.
The presence of isozyme of isocitrate lyase was not detected in C. lipolytica. The isocitrate lyase of C. lipolytica could cleave 2-methylisocitrate at a rate of 3% of that of isocitrate cleavage. On the contrary, methylisocitrate lyase hardly acted on isocitrate. Two lyases differed in chromatographic elution patterns, pH optima, kinetics of thermal inactivation, and behavior with inhibitors, such as itaconate and oxalate, in addition to substrate specificity. The experimental results revealed that methylisocitrate lyase is impossible to be the isozyme of isocitrate lyase, and justified the previously proposed ideas that propionyl-CoA is oxidized through the methylcitric acid cycle in C. lipolytica and that the absence of this enzyme in the mutant strain caused the extracellular accumulation of 2-methylisocitrate from odd-carbon n-alkanes.

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The 2% solution of a natto mucin behaved as a thixotropic flow at pH 5.7, although the flow of the same concentration was apparently Newtonian at pH 4.3. In the 6% solution the viscometric behavior at pH 4.3 was almost the same as that at pH 5.7. The results can be explained in terms of the conformational change of the molecule according to the pH change; that is, the mucin molecule is randomly coiled at pH 5.7 and a rod-like molecule at pH 4.3. The conformational change was shown by means of the electron microscope.

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Recent advances in the synthesis of cytokinin analogs have revealed the peculiar nature of pyrrolo [2, 3-d] pyrimidine derivatives some of which behave as anticytokinins.^1_??_3) The development of the synthetic studies of anticytokinins immediately suggests their practical usage as plant growth regulators⁴⁾ as well as the utilization for the studies on the mechanism of cytokinin action. Here we wish to report an experiment in which the growth promoting activity of some 4-substituted pyrrolo [2, 3-d] pyrimidines (Ia-If) was compared with the growth retarding activity of the corresponding, previously reported anticytokinins, 4-substituted 7-(β-D-ribofuranosyl) pyrrolo [2, 3-d]-pyrimidines (IIa-IIf).^{1, 2)}

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