The energy source and energy coupling reaction of the active transport system for α-aminoisobutyric acid (AIB) in alkalophilic Bacillus no. 8-1 were studied.
Various metabolites such as glucose and succinate served as substrates for respiration and AIB uptake. Glucose also stimulated the synthesis of ATP. Potassium cyanide inhibited both respiration and AIB uptake to the same extent but uncouplers or ionophores inhibited AIB uptake much more than respiration. Arsenate had no inhibitory effect on these activities.
The inhibition of AIB uptake by uncouplers or ionophores was recovered by the addition of glucose at 20mM concentration. The cellular ATP level was reduced by carbonylcyanide-m-chlorophenylhydrazone (CCCP) but this inhibition was also reversed by the addition of glucose.
These results suggest that a coupling reaction for AIB uptake is driven by energized membrane states.

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Thermoactinomyces vulgaris α-amylase was purified to an electrophoretically homogeneous state, and its properties and action on starch, pullulan, maltooligosaccharides and partial hydrolyzates of pullulan were studied. Both starch-hydrolyzing and pullulan-hydrolyzing activities of the enzyme were inhibited by Al³⁺, Cu²⁺, Hg²⁺, p-chloromercuribenzoate, maltotriitol, panitol, isopanitol and some microbial α-amylase inhibitors to nearly the same extent. Km and V_max values of the enzyme for short chain amylose (DP=17) and pullulan, Ki values for sugar alcohols and α-amylase inhibitors, and the kinetics of the simultaneous presence of short chain amylose and pullulan supported the view that the hydrolytic action of the enzyme on starch and pullulan is due to a single catalytic site. Action patterns of the enzyme on maltooligosaccharides and partially hydrolyzed pullulan were examined, and it was suggested that this α-amylase can attack some of the (1→6)-α-D-glucosidic linkages in partial hydrolyzates of pullulan as well as (1→4)-α-D-glucosidic linkages in starch and pullulan.

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Cell walls were obtained from yeast (Y)- and rod (R)-forms of Candida krusei. These Y- and R-form cells were grown in synthetic media containing lysine and alanine as nitrogen sources, respectively. Comparative analysis of their walls showed that the Y-form wall had greater quantities of alkali-soluble glucan, alkali-insoluble glucan and mannan than the R-form wall had.
The glucan from Y-form walls had a larger amount of β-1, 3-glycosidic linkage with a few branches at the C-6 position and a smaller amount of linear β-1, 6-glycosidic linkage than the glucan from R-form walls had. There was, however, no significant difference in the chemical structure of mannan between the walls of these two forms.
The results are discussed in relation to the chemical composition and structure of polysaccharides of walls in the yeast-rod dimorphism.

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A cycloheptanone (C₇ON)-utilizing bacterium, strain KUC-7N, has been isolated from soil and classified as a strain in the genus Nocardia. The bacterium could also utilize six other kinds of alicyclic compounds; on cyclohexanone (C₆ON) and cyclohexanecarboxylic acid (C₆CA) it showed good growth without a lag time, while on cyclopentanone (C₅ON), cyclooctanone (C₈ON), cyclopentanecarboxylic acid (C₅CA) and cycloheptanecarboxylic acid (C₇CA) there was a lag time of 3 to 7 days. The cells preincubated with C₇ON showed about a 4 times higher Q_O2 (182) for C7ON than the cells grown on glucose. The metabolite of C₇ON in the culture broth was identified as pimelic acid. It was assumed that C₇ON is metabolized via 1-oxa-2-oxo-cyclooctane, 7-hydroxyheptanoic acid and pimelic acid.

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A base-specific ribonuclease (RNase) Lu (EC 3.1.27.5) was isolated and purified from Aspergillus niger in a yield of 23% by means of acetone precipitation, column chromatography on Duolite A-2, DEAE-cellulose, and 2'(3')-aminohexyl-5'-ATP-Sepharose 4B. The enzyme was shown to be homogeneous by disc-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be 43000 by both gel filtration and SDS-gel electrophoresis.
The isoelectric point of the enzyme was determined to be 3.75 by isoelectric focusing. The enzyme had a base specificity: it released only 3'-UMP from yeast RNA or poly(U) and, in addition, small amounts of 3'-CMP from poly(C).

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Asymmetric hydrolysis of (±)-1, 2-diacetoxy-3-chloropropane (1) with a very small amount of a lipoprotein lipase gave (S)-1 of 90% enantiomeric excess (e.e.). Reactions of (S)-1 with phenols in an alkaline condition yielded the corresponding (S)-3-aryloxy-1, 2-propanediols. From (S)-3-(1-naphthoxy)-1, 2-propanediol (5) was synthesized the optically pure (S)-isomer of propranolol [1-isopropylamino-3-(1-naphthoxy)-2-propanol] (9), one of the β-adrenergic blocking agents. Hydrolysis of (±)-1, 2-diacetoxy-3-bromopropane (11) and (±)-1, 2-diacetoxyethylbenzene (12) with the lipase afforded (S)-11 of 77% e.e. and (R)-12 of 73% e.e., respectively.

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In order to obtain lipases similar to that of pancreatic origin, some 1000 bacteria isolated from soil were screened in respect to the following characteristics: (1) optimum pH for activity is in the alkaline region, (2) lipase activity is stimulated by bile salts and (3) a large amount ofmonoglyceride is accumulated during fat hydrolysis. The 14 selected isolates were divided into two groups from the preservation profile; bacteria of group I were viable for a long period on nutrient agar medium, while group II bacteria were all dead within 20 days on nutrient agar slants. Some properties of lipases produced by these bacteria were preliminarily examined with respect to the similarity to the pancreatic lipase and a promising strain was isolated from each group. The two strains were examined for microbiological characteristics and suggested to be new species belonging to the genus Alcaligenes.

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A new enzyme, aliphatic nitrile hydratase, which hydrates acetonitrile to form acetamide was purified from the cell-free extract of acetonitrile-grown Arthrobacter sp. J-l. The overall purification was about 290-fold with a yield of 10%. The purified enzyme was homogeneous as judged by ultracentrifugation and disc gel electrophoresis. The enzyme catalyzed the stoichiometric hydration of acetonitrile to form acetamide according to the following scheme: CH₃CN+H₂O →CH₃CONH₂. The enzyme was inducibly formed and then amidase which hydrolyzed acetamide was formed. The molecular weight of the enzyme was determined to be about 420, 000 by gel filtration. The enzyme was composed of two kinds of subunits, of which the molecular weights were 24, 000 and 27, 000. The isoelectric point was 3.6. The enzyme was active toward low molecular weight aliphatic nitriles of 2 to 5 carbon atoms. The Km value for acetonitrile was determined to be 5.78mM. The enzyme was inactivated by sulfhydryl reagents. The enzyme was competitively inhibited by potassium cyanide: the Ki value was 1.5 μm.

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Amidase was purified from the cell-free extract of acetonitrile-grown Arthrobacter sp. J-1 by a procedure involving protamine sulfate precipitation, ammonium sulfate fractionation, and column chromatographies on DEAE-cellulose, hydroxyapatite and Sephadex G-200. The overall purification was 47-fold. The purified enzyme was homogeneous as judged by ultracentrifugal analysis and disc gel electrophoresis. The molecular weight of the enzyme was estimated to be about 300, 000 and 320, 000 by disc gel electrophoresis and gel filtration, respectively. The enzyme was possibly composed of eight identical subunits of a molecular weight of 39, 000. The isoelectric point was 3.8. The enzyme catalyzed the stoichiometric hydrolysis of acetamide to form acetic acid and ammonia. The enzyme was active toward acetamide, acrylamide and propionamide and the Km values were 0.97, 23.3 and 8.05 mM, respectively. The enzyme showed acyltransferase activity.

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To produce acrylamide from acrylonitrile by use of a new enzyme, nitrile hydratase, a number of nitrile-utilizing microorganisms were screened for the enzyme activity by an intact cell system. An isobutyronitrile-utilizing bacterium, strain B23, showed the best productivity among 1 86 strains tested. The strain was identified taxonomically as Pseudomonas chlororaphis. The culture and reaction conditions for the production were studied for the strain. Under the optimum conditions, 400 grams/liter of acrylamide was produced in 7.5hr. The yield was nearly 100% with a trace amount of acrylic acid. The cell-free extract of the strain showed strong activity of nitrile hydratase toward acrylonitrile and extremely low activity of amidase toward acrylamide.

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Galactose oxidase was purified from the culture supernatant of Gibberella fujikuroi by ammonium sulfate precipitation, chromatographies on DEAE-cellulose and hydroxylapatite, and gel filtration on Bio-Gel P-100. The purified enzyme had a molecular weight of 90, 000 and an isoelectric point of pH 3.7, and contained about one atom of copper and about one atom of iron per mol of the enzyme protein. The enzyme was markedly inactivated by a copper-chelating agent, diethyldithiocarbamate, and reducing agents. The apoenzyme preparing on treatment of the enzyme with diethyldithiocarbamate could be reactivated only by the addition of either Cu⁺ or Cu²⁺. These results indicate that copper is involved in galactose oxidase activity of G. fujikuroi.

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Antioxidant activities as measured by the peroxide value, and the thiobarbituric acid or oxygen uptake methods were observed on a reaction mixture of dehydroascorbic acid with tryptophan. This was stronger than any of the activities of similar amino-carbonyl reaction mixtures tested and was comparable to BHA. The strongest activity was developed when an equimolar mixture of the reactants in 95% ethanol were heated for 30 min in a boiling water bath. In the antioxidant action, the presence of α-tocopherol acted synergistically. When the mixture was fractionated by TLC on a cellulose plate a brown colored fraction proved strongly effective by the POV method. Another fraction, effective in the oxygen uptake method but not in the POV method, was found mainly consisting of ascorbic acid. Other fractions which were identified before and related to the free radical formation were all inactive.

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Several substances with antioxidant activity were isolated from the mixture of dehydroascorbic acid and tryptophan when reacted together in ethanol. One of the main antioxidant products was obtained in crystalline form from an n-butanol extract of the reaction mixture by means of Sephadex column chromatography followed by HPLC with a reversed phase column. ¹H- and ¹³C-NMR of the product and its acetate showed its structure as a condensate of dehydroascorbic acid and tryptophan with each single molecule involving a C-spiro structure. By a POV test the activity of this substance was about two-thirds of that of BHA on a molar basis, and the activity of the reaction mixture is greatly attributable to this substance.

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In this paper, we present a simple and sensitive method for the assay of intracellular neutral lipids of the yeast, Lipomyces starkeyi. In this method, we used a tower-shaped mixer for cell disruption and applied a diagnostic triglycerides assay kit as a sensitive color developer. This mixer could treat 14 samples at one time. No effect of pH on cell disruption was detected within the pH range of 1.6 to 6.8. Twenty min was chosen for cell disruption and for homogeneous dispersion of intracellular neutral lipids. The analytical results agreed well with those obtained by three conventional methods. The new method is simpler and of good reliability.

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The absolute configurations of twelve α-aryl and α, β-diarylalkylamines were studied as N-acyl derivatives by circular dichroism (CD) measurements and by gas Chromatography (GC).
The signs of Cotton effects for the S-configuration around 260 nm were positive and those around 210nm were negative, although some exceptions were found due to the substituents on the benzene nuclei. In contrast, the GC behavior was considered less sensitive to the substituents on the benzene nuclei, and the elution orders were an R-before S-configuration consistently on a chiral OA-300 column. The absolute configurations of some amines were estimated in this study. GC as well as CD measurements could be a promising method for the assignment of the absolute configuration.

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D-Glucosamine (GlcN) inhibited hyphal growth of Pyricularia oryzae P₂ although it did not inhibit germination of conidia. The degree of inhibition varied according to the sugar, being the highest in the case of sucrose and the lowest in the case of glucose among the sugars tested. Uptake of GlcN was severely inhibited by glucose whereas uptake of glucose was not inhibited by GlcN. Glucose was the most effective among the sugars tested in the inhibition of GlcN uptake. GlcN caused morphological changes in both colonies and hyphae. The most characteristic change was a swelling of hyphae. Analysis of cell walls indicated that the cell wall of swollen hyphae contained more than twice as much N-acetylglucosamine and smaller amounts of other sugars as those found in normal hyphae.

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Published data of the effective thermal conductivities of meats were analyzed in relation to approximate compositions of the meats. On the basis of series heat conduction model, the "intrinsic" thermal conductivity value of meat protein was estimated to be 0.342 [W/m•°C] when unfrozen, and 0.581 [W/m•°C] when frozen. Using these "intrinsic" values and the series heat conduction model, the effective thermal conductivities of meats were reversely predicted from the contents of water and fat. Standard deviations of the published data from the predictions were ±7.0% for unfrozen meats and ±15.4% for frozen meats. If heat flow is parallel to the meat grain, published data for frozen meats are higher than the predictions by about 20% as a mean.

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A lytic enzyme activity (N-acetylmuramidase activity) was found in the supernatant fluid of an exponentially growing culture of Clostridium saccharoperbutylacetonicum (ATCC 13564). The same enzyme activity was also found in the autolysate of the cells and the isolated crude cell walls. This enzyme was considered to be autolysin of C. saccharoperbutylacetonicum. This autolysin lysed the cell walls of C. saccharoperbutylacetonicum and some other clostridia, but whole cells and their glycan moiety hardly at all. Its optimum pH was about 4.5 and optimum temperature was about 35°C. Its molecular weight was 44, 000.

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Transplacental transfer of chlorinated hydrocarbons such as PCBs, DDT compounds, HCH isomers and HCB was determined in a pregnant striped dolphin just before parturition. The transfer rates of chlorinated hydrocarbons in the striped dolphin through parturition were estimated as follows: PCBs 4.0%, ∑DDT 4.7%, ∑HCH 8.9% and HCB 9.4%. The concentration ratios of chlorinated hydrocarbons in the blubber of the fetus to that of the mother dolphin were found to be in the order of HCB > HCH isomers > DDT compounds > PCBs. Especially in PCB congeners, these ratios gradually decreased with the increase of chlorine atoms substituted in biphenyls.
These observations indicate that the more lipophilic chemicals, such as higher chlorinated biphenyls and DDT compounds, are less transferable from mother to fetus. The transfer characteristics of chlorinated hydrocarbons can be explained by their equilibrium partitionings between blood and blubber, resulting from the differences of lipid compositions in each.

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Bacillus pumilus BN-103 was found to produce a new antibiotic complex named amicoumacin. The antibiotic was isolated from the culture broth by ion-exchange resin and carbon chromatographies. Amicoumacin A was a major component of the mixture, and exhibited not only antibacterial activity, but also antiinflammatory and antiulcer activities. Amicoumacin B and C showed moderate activity against bacteria, but did not exhibit any pharmacological activity.

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Two enzyme preparations having both nuclease and 3'-nucleotidase activities were partially purified from an extract of tea leaves. They resemble each other in most enzymatic properties, but are separated by DEAE-cellulose column chromatography.
The enzyme activities for RNA, native DNA, heat-denatured DNA and 3'-AMP of each preparation showed a high degree of similarity with respect to the following properties: pH stability, thermal stability and response to EDTA. Both enzymes were shown to be endonucleases (EC 3.1.30.2) which liberated 5'-mononucleotides and oligonucleotides from both RNA and DNA with the following relative rate of hydrolysis: RNA>native DNA=heat-denatured DNA.

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The racemization of optically active imidazoline derivatives catalyzed by amines and alcohols was investigated. The racemization was effected by the catalysis of primary and secondary amines, but not by tertiary amines. In t-BuOH, imidazolines were racemized much more slowly than in primary alcohols. The mechanism through a pseudo-six-membered cyclic transition state was proposed for the racemization.

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In order to discover more potent pyrethrum synergists, dihydrodillapiole and furapiole, two dillapiole-based compounds having considerable synergistic activity, were converted into various acyl and α, β-unsaturated carbonyl derivatives. The synthesis, factor of synergism, spectroscopic data and structure activity relationships of these derivatives are reported.

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The sulfated glycopeptides in ovomucin, chalazae and yolk membrane were isolated from the proteolytic digests by gel filtration on a Bio-Gel P-100 column and DEAE-Sephadex A-25 column chromatography. These sulfated glycopeptides contained N-acetylhexosamine (23.3-26.8%), hexose (23.6-24.4%), sialic acid (11.2-18.0%), sulfate (5-12.1 %) and peptide (17.5-18.1 %). The sulfate contents of glycopeptides in chalazae and yolk membrane were much higher than those in Ovomucin, about two times in a molar ratio to hexosamine. The sedimentation patterns of each sulfated glycopeptide were single and the sedimentation constants were around 3 S, suggesting that these sulfated glycopeptides were macromolecular components. Thus, the presence of highly sulfated glycoproteins was confirmed in chalazae and yolk membrane, which were different from those in ovomucin.

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N-Material was purified from soy sauce by dialysis against water and column chromatography on Sepharose 6B and DEAE-Sephadex A-50. The purified preparation was homogeneous on disc electrophoresis and the material consisted of almost pure protein with a trace amount of carbohydrate. The protein was characterized by higher contents of threonine, glycine, valine, isoleucine and lower contents of proline, cystaine and lysine than the soybean protein was. The molecular weight of the material was estimated to be approximately 210, 000 by Sephadex G-200 gel filtration method. N-Material, N-soy sauce and N-raw soy sauce gave a maximum turbidity at pH 5.0-5.5.
N-Material gave four protein bands on SDS-polyacrylamide gel electrophoresis and their mobilities were 0.43, 0.51 (trace), 0.71 (major) and 1.05 (minor), whose molecular weights were 45, 000, 37, 000, 22, 500 and 11, 000, respectively. There was no clear protein band on polyacrylamide gel electrophoresis in the acidic-urea system.
N-Material was digested by koji alkaline protease in low ionic strength, but not digested in the higher ionic condition.

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The distribution of γ-glutamylcysteine synthetase (L-glutamate: L-cysteine γ-ligase, EC 6.3.2.2) was investigated in bacteria, and the enzyme was purified from Proteus mirabilis approximately 9, 000-fold with an over-all yield of 10%. The purification procedure included ammonium sulfate fractionation, protamine treatment, DEAE-cellulose and- hydroxylapatite column chromatographies and Sephadex gel filtrations. The purified enzyme was homogeneous by the criteria of ultracentrifugation. It showed multiple bands on disc-polyacrylamide gel electrophoresis and on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. One band with a molecular weight of 62, 000 was obtained on SDS-polyacrylamide gel electrophoresis after cross-linking of the enzyme with dimethylsuberimidate. The molecular weight was determined from the sedimentation and diffusion coefficients to be 64, 000 and by Sephadex G-150 gel nitration to be 62, 000. The purified enzyme catalyzed the stoichiometric formation of γ-glutamylcysteine and the reaction showed a sigmoidal dependence upon L-cysteine concentration. The enzyme also catalyzed γ-glutamyl amino acid formation from L-α-aminobutyrate, L-homoserine, glycine, L-serine, DL-norvaline or DL-homocysteine, but at lower rates than from L-cysteine. The γ-glutamyl-α-aminobutyrate formation by the enzyme did not show a sigmoidal but a hyperbolic dependence upon L-α-aminobutyrate concentration.

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Chlorogenic acid and rutin, major polyphenols in tobacco, were pyrolysed with a furnace type pyrolyser connected directly to a gas chromatograph and 22 compounds (including catechol, benzoic acid, 4-vinylcatechol and quinic acid γ-lactone) from Chlorogenic acid and 24 compounds [including catechol, 5-methyl-2-furaldehyde, 4-methylcatechol and 1, 6-anhydroglucopyranose (levoglucosan)] from rutin have been identified as pyrolysis products. The gas chromatograph was also replaced by a capillary cold trap which allowed collection of the pyrolysis products prior to a quantitative determination using an internal standard. Comparison of the pyrolysis products produced from chlorogenic acid or rutin with those derived from tobacco and analysis of the pyrolysis products from a mixture of tobacco and chlorogenic acid or rutin indicated that fairly large proportions of catechol, 4-vinylcatechol and quinic acid γ-lactone produced by the pyrolysis of tobacco may originate from endogenous chlorogenic acid.

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Ferredoxin-dependent nitrite reductase of spinach has been further characterized and the relationship between this enzyme and methyl viologen-dependent nitrite reductase studied.
Purified ferredoxin nitrite reductase, having a molecular weight of 86, 000, showed 2.5 times higher ferredoxin-dependent activity than methyl viologen-linked activity. Besides 4 mol of labile sulfide the enzyme contained about 2 mol of siroheme per mol. When dithionite, methyl viologen and nitrite were added, ESR signals of a heme nitrosyl complex at g=2.14, 2.07 and 2.02 were observed. Moreover, hyperfine splitting of the signal due to ¹⁴N nuclear spin was also observed at 2.033, 2.023 and 2.013. The sole addition of hydroxylamine to the ferric enzyme also caused the same but much less intense signals with the hyperfine splitting.
On treatment of the ferredoxin nitrite reductase (native enzyme) with DEAE-Sephadex A-50 chromatography, a modified nitrite reductase having a molecular weight of 61, 000 and a protein fraction having an apparent molecular weight of 24, 000 were separated. The modified enzyme contained about one mol of siroheme and 4 mol of labile sulfide per mol and showed essentially the same heme ESR signals as the native enzyme. Contrary to the native enzyme, this modified enzyme accepted electrons more efficiently from methyl viologen than ferredoxin and the reduction of nitrite to ammonia catalyzed by the modified enzyme was not stoichiometric. The observed nitrite to ammonia ratio was 1 to less than 0.6. Cyanide at concentrations between 0.02 to 0.2 mM inhibited the activity of the native enzyme almost completely but the modified enzyme was inhibited only partially.
From the results obtained, it is suggested that the native ferredoxin-linked nitrite reductase consists of two components (or subunits) and removal of the light component results in formation of a modified enzyme with increased relative affinity to methyl viologen.

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Surviving fractions of Escherichia coli B exposed to an alternating current (AC) of 50 Hz in a phosphate buffer solution of pH 7.0 at 29°C were closely related to the amount of H₂O₂ formed in cell suspensions. At a definite current density, the amount of H₂O₂ in the suspensions or in buffer solution without cells increased with increasing AC-exposure time under aerobic conditions. On the other hand, the formation of H₂O₂ on AC-exposure was not detected under anaerobic conditions. It was considered that H₂O₂ was formed on the surface of carbon electrodes by AC-electrolytic reduction of dissolved oxygen. The amount of H2O2 formed decreased with increasing concentration of cells suspended or of catalase added to the suspension. When the formation of H₂O₂ was significantly suppressed, surviving fractions of cells exposed to AC remained almost unchanged. Growth conditions, modifying the intracellular level of catalase of E. coli, affected the sensitivity of cells to AC-exposure.

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Experiments were done to investigate the volatile components in botrytized grape must and transformation of terpenoids in terpene-supplemented grape must by Botrytis cinerea. Twenty-eight compounds were identified in the volatile concentrate of botrytized must with a combined gas chromatograph-mass spectrometer. No terpenoids were detected in the concentrate. Linalool or terpinen-4-ol decreased a lot when Botrytis cinerea was cultured in the must with these terpenes for 15 days. In linalool-supplemented botrytized must 9 identified and 3 unidentified terpenes were found, while only geranial was detected in terpinen-4-ol-supplemented botrytized must. Botrytis cinerea did not produce terpenoid in grape must without terpenes, but transformed linalool added to grape must into some other monoterpenes.

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A new enzyme, agmatine oxidase, was found in Penicillium chrysogenum. The oxidation products of agmatine with the enzyme were identified as γ-guanidinobutyraldehyde, NH₃ and H₂O₂. Theenzymerapidlyoxidizedagmatine, and slightly oxidized histamine, putrescine, 1, 3-diaminopropane and cadaverine. Monoamines, polyamines and guanidyl derivatives were not oxidized by the enzyme. Maximal formation of the enzyme of P. chrysogenum was observed in the early stationary phase of growth, and thereafter the enzyme disappeared with consumption of substrate. In addition to agmatine, spermine, spermidine and putrescine were also effective as nitrogen sources. Agmatine oxidase was found in mycelia of fungi belonging to the genera of Aspergillus, Penicillium, Absidia, Fusarium, Mucor, Gibberella, Cylindrocarpon and Monascus when they were grown in agmatine-containing medium.

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Agmatine oxidase was purified and crystallized with an overall yield of about 30% from a mycelial extract of Penicillium chrysogenum by a procedure involving ammonium sulfate fractionation, and DEAE-cellulose, hydroxyapatite, 1, 8-diaminooctane-Sepharose 4B and Sephadex G-200 column chrcmatographies. The purified enzyme was homogeneous on disc gel electrophoresis and the pink crystals appeared as a hexagonal board on addition of solid ammonium sulfate. The molecular weight of the native monomer form was determined to be 160, 000 by gel filtration, and it was composed of two identical subunits. The prosthetic group was identified as copper and its content was determined to be 2 mol per mol of the enzyme. The enzyme was inhibited by hydroxylamine, hydrazine, phenylhydrazine, semicarbazide, KCN, PCMB, Ag⁺, Hg²⁺ and Cu²⁺. The apparent Km values for agmatine, histamine and putrescine were calculated to be 2.51 × 10^-4M, 4.25 × 10^-4M and 1.64 × 10^-2M, respectively.

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3-Guanidinopropionate amidinohydrolase, a new enzyme (EC class 3.5.3), was purified 220-fold from Pseudomonas aeruginosa PAO 1 grown on 3-guanidinopropionate. The enzyme was found to be essentially homogeneous on polyacrylamide gel electrophoresis. The molecular weight of the native enzyme was estimated to be 195, 000-215, 000. The subunit molecular weight was estimated to be 36, 000. The optimal pH was 9.0. The Km value for 3-guanidinopropionate was 45mM. Incubation of the enzyme with EDTA in potassium phosphate buffer, pH 7.0, at 40°C resulted in almost complete inactivation, and the inactive enzyme was specifically reactivated by Mn²⁺. Taurocyamine (11%) and 4-guanidinobutyrate (3%) were hydrolyzed as fast as 3-guanidinopropionate at the relative rates indicated. The enzyme was inactivated by p-chloromercuribenzoic acid and the inactive enzyme was reactivated by incubation with 2-mercaptoethanol. Coelectrophoresis of the enzyme with 4-guanidinobutyrate amidinohydrolase purified from Pseudomonas sp. ATCC 14676 in polyacrylamide gels in the presence and absence of sodium dodecyl sulfate demonstrated their close mobilities. 4-Aminobutyrate, propionate, and n-butyrate were common competitive inhibitors of these enzymes. The evolutionary relationship between the two enzymes was discussed.

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A simple and an efficient synthesis of methyl jasmonate (1) and methyl dihydrojasmonate (5) is described. Starting from alkyl acetoacetate or acetonedicarboxylate, 1 and 5 were obtained in only a few steps via intramolecular Michael addition.

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