The enzyme, N-acetylmuramyl-L-alanine amidase (mucopeptide aminohydrolase EC 3.5. 1. 18) was found in mutanolysin, which was purified partially from the cultural broth of Streptomyces globisporus 1829. This enzyme was highly purified. The overall purification was 37.5-fold with a yield of 19.2% from mutanolysin. The molecular weight of the enzyme was 18, 500 as determined by plate gel filtration. The enzyme was inhibited by Cu⁺⁺. This enzyme has a preference for substances of lower molecular weight and seems to be dependent on the prior action of a hexosamidase. This enzyme is not bacteriolytic per se.

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Growth thermograms of bakery yeast grown on a liquid synthetic mediumcontaining glucose as a limiting energy source were studied at various temperatures. Kinetic analysis of the thermogramswas performed to obtain the apparent maximumgrowth rate constant and the substrate constant. By using the Arrhenius equation, the activation energy of growth was estimated to be E_A=56.3±5.1 kJmol^-1. From the variation of the substrate constant over the temperature range studied, the enthalpy change of glucose uptake by the yeast cells was determined to be AH=-6.2±2.5kJmol^-1. The corresponding Gibbs energy and entropy changes were ΔG=-16.4±0.2kJ mol^-1 and ΔS=34.2±8.4J mol^-1K^-1 at 25°C, respectively.

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Administration of a high dose (100 μg) of 20-hydroxyecdysone to a Bombyx pupa aged 2 days caused a reduction in content of ribosomes, translatable mRNA, and polysomes of the ovaries. This coincided with the lower relative content of putative chorion proteins in the hormone-treated pupae. However, no large influence of the hormone treatment was detected at the translational level. The developmental time of the ovaries was muchprolonged in the hormone-treated animals, and this seemed to compensate for the above decrease in protein content and finally caused a deposition of a normal amount of chorion proteins in oviposited eggs. These results support the idea that the amount of chorion proteins is related to the developmental time of the ovary.

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When washed mycelium of Streptomyces griseus HUT 6037 was incubated in 0.5% NaCl solution containing ¹⁴C-gl cosamine with shaking at 28°C, the activity of the mycelium to incorporate radioactivity into the cell wall decreased rapidly, while that into streptomycin increased. During this physiological change, UDP-Af-acetylmuramyl-pentapeptide, UDP-N-acetylglucosamine, glutamic acid and trehalose accumulated in the mycelium. The latter two substances accumulated much more than the former two. When the time courses of the activities of incorporation of ¹⁴C-glucosamine into the four substances, mucopeptide and streptomycin were examined, a decrease in the activity into peptidoglycan led to an increase into streptomycin, glutamic acid and trehalose.
In a pH-stat batch culture with a defined medium, trehalose was accumulated in the cell before glucose was consumed. However, after glucose was consumed, the consumption of trehalose began. Streptomycin production continued until intracellular trehalose completely disappeared in spite of the lack of glucose in the culture medium.

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When the mycelium of Streptomyces griseus HUT 6037 was suspended in 0.5% NaCl solution containing ¹⁴C-glucosamine, peptidoglycan precursors accumulated in the cells. While UDP-7Vacetylglucosamine accumulated in the largest amount among the precursors, extracellularly added and intracellularly accumulated UDP-N-acetylglucosamine were not used to synthesize streptomycin and were probably used for peptidoglycan formation.
On the other hand, correlation was recognized between accumulation of glucosamine-6- phosphate (GlcN-6P) and treptomycin formation. Addition of an inhibitor of peptidoglycan synthesis such as enduracidin, vancomycin or cycloserine to a mycelium-suspended culture changed the ratio of accumulated peptidoglycan precursors. When streptomycin formation was stimulated by addition of enduracidin or vancomycin, intracellular GlcN-6P remarkably increased and then decreased rapidly. On the contrary, when cycloserine was added to the culture, no increase ofGlcN- 6P was observed and streptomycin formation was not stimulated. These results suggest that an increase in the intracellular concentration of GlcN-6P is required for activation or induction of the system for utilizing GlcN-6P for streptomycin formation.

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An alkaline phosphodiesterase has been purified 2200-fold from the fruit body of Flammulina velutipes. The molecular weight is about 53, 000. The optimum pH for hydrolysis of bis-pnitrophenyl phosphate is 8.0. This phosphodiesterase is stable for 30 min below 40°C and in a pH range from 5.5 to 6.5. The Km values for bis-p-nitrophenyl phosphate and p-nitrophenyl deoxythymidine 5'-phosphate are 0.25mM and 0.09mM, respectively. The enzyme does not hydrolyze RNA and DNA, whereas adenosyl uridine 5'-phosphate is hydrolyzed at a considerable rate. The phosphodiesterase also hydrolyzes NAD, UDP-glucose, and ADP-ribose but does not act on ATP and cyclic AMP.

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We have cloned a butirosin resistance gene located on a 2.9Md HindIII fragment of the chromosomal DNA of Bacillus vitellinus Z-1159, a butirosin producer, on a shuttle vector, pTA1302 (5.2Md, Ap^r, Cm^r). The recombinant plasmid conferred resistances to butirosin, neomycin and kanamycin, on both Escherichia coli and Bacillus subtilis. Functional expression of aminoglycoside-B '-phosphotransferase activity from the butirosin resistance gene was confirmed in the cell extracts of both E. coli and B. subtilis harboring the recombinant plasmid. A cleavage map of the recombinant plasmid was constructed.

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Corynebacterium equi IFO 3730, which had been shown to have an enzyme system for oxidizing a wide variety of linear secondary alcohols, gave the corresponding ketones on incubation with cycloalkanols. The bacterium showed an interesting substrate specificity, i.e., although cyclohexanol and cyclododecanol were oxidized smoothly, a large portion of cyclooctanol was recovered unaffected under the same conditions. The stereochemistry of the substrates had a marked effect on this microbial transformation, cis and trans-4-tert-Butylcyclohexanol showed a remarkable contrast, in that the former was oxidized smoothly by C. equi but the latter was little affected.

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The amino acid distribution in the floral organs of Nicotiana tabacum was studied at 2 days after anthesis an in the developmental stages of the stigma and anther. Free amino acid contents of the organs were higher than in leaves on a dry weight basis. All the organs contained a large amount of asparagine and glutamine. Asparagine was prominent in the anther and pistil, while glutamine was higher in the others. The proportion ofserine was exclusively high in the stigma and style. The calyx, floral axis and anther contained an appreciable amount of proline. Bound amino acid compositions were similar among the floral organs, although electrophoretic behaviors of the soluble protein fractions in polyacrylamide gels were different.
Protein accumulation during development was observed in both the stigma and anther. On the other hand, the co tent of free amino acids of the stigma increased during development, while that in the anther decreased at the later stages. The rapid increase of asparagine in the anther was observed 1 day before anthesis, and 6 days before in the stigma. Proline was one of the major amino acids in the anther at anthesis and its maximum concentration was observed at 3 days before anthesis. The proportion of glutamine rapidly decreased in both the stigma and anther during development.

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Formation of acetate esters by brewers' yeast during sugar fermentation was investigated in relation to alcohol acetyltransferase activity influenced by the fatty acid composition of the yeast cell membrane. Glucose gave more acetate esters with a higher activity of alcohol acetyltransferase than the other carbohydrates. When maltose was fermented, the activity of alcohol acetyltransferase bound to the cell membrane was suppressed by unsaturated fatty acids accumulated in the cell membrane and the formation of acetate esters was greatly reduced without insufficient fermentation. On the other hand, when fructose was fermented, the ester formation was reduced with a decrease in the enzyme activity and the formation of higher alcohols through insufficient fermentation.

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When intact cells of Saccharomyces cerevisiae were treated with alkali cations or thiol compounds, the cells gained the ability to take up plasmid DNAs. The transformation efficiencies of yeast cells treated with alkali cations was greatly influenced by both the kind and concentration of cation used. The transformation efficiency also varied depending on the yeast strain. Polyethylene glycol was indispensable for the transformation. The uptake of plasmid DNAs into the yeast cells was found only in the presence of this polymer. Based on these results, the properties of transformation of intact yeast cells treated with alkali cations or thiol compounds were discussed.

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Leucine dehydrogenase (EC 1.4. 1.9) from Bacillus sphaericus was inactivated by pyridoxal 5'- phosphate, although less than 50% by one treatment. The inactivation was pH-dependent; the enzyme was most easily inactivated at pH 8.0. The inactivation was reversible by dialysis of the inactivated enzyme, but became irreversible when the inactivation was followed by reduction of the enzyme with NaBH₄. The inactivation by pyridoxal 5'-phosphate was accompanied by the concomitant appearance of a peak at 427nm, which was shifted to 325nm by reduction with NaBH₄. Amino acid analysis of an acid hydrolysate of the pyridoxal 5'-phosphate-inactivated and NaBH₄-reduced enzyme showed the presence of ε-N-pyridoxyl-lysine. Thus, the inactivation is probably due to Schiff base formation between pyridoxal 5'-phosphate and an ε-amino group of a lysine residue of the enzyme. The enzyme was fully protected from inactivation only by NADH. The repeated treatment of the enzyme with pyridoxal 5'-phosphate and NaBH₄ led to complete irreversible inactivation of the enzyme through a stepwise decrease in the activity. The substrate specificity and Km values of the partially inactivated enzyme were not essentially different from those of the native one.

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Enzyme-enzyme heteroconjugates of phosphoglyceromutase, enolase and pyruvate kinase, which sequentially act to produce ATP in the glycolytic pathway, were constructed with a bifunctional reagent, N-succinimidyl 3-(2-pyridyldithio)propionate. The conjugates of phosphoglyceromutase- enolase, enolase-pyruvate kinase and phosphoglyceromutase-enolase-pyruvate kinase were purified so as to be free from free forms of enzymes and properties of the conjugates were investigated in terms of overall reactions, and Km values and heat stability of each enzyme in the conjugates. When the initial phase of the overall reaction catalysed by a conjugate was compared with that by a mixture of the free enzymes, it was found that the lag time required for the system to achieve a steady-state was reduced in the conjugate system. This was true for all conjugates constructed. Nosignificant increases in the Km values of the enzymesin conjugates were noted. Improvement of stability against heat was not observed for any conjugates.

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At levels of 10μg/ml (≈ 10^-5 m), MAPI, a peptidealdehyde type serine protease inhibitor, selectively inhibited sporulation of B. subtilis without appreciably altering exponential growth. The strongest inhibition ofsporulation is observed when the inhibitor is added within the first 3-4 hr of sporulation.
Using [¹⁴C]MAPI, the existence of an MAPI-binding substance was investigated. More than 50%of the incorporated MAPIformed a complex with a constituent of the membrane. This substance was identified as the membrane bound protease [Shimizu et al., Agric. Biol Chem., 47, 1 775 (1 983)] from chromatographic and enzymatic properties. These results strongly suggested that the inhibition of sporulation of MAPImay be due to repression of proteolytic activity of the membranebound enzyme through the complex formation. They also suggested that all the essential function of the enzymewas complete before t₄.

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A potent germination inhibitor was found in the n-hexane soluble fraction of the methanolic extract of Eucalyptus pulverulenta. This inhibitor was identified as grandinol (1) which had been isolated from E. grandis. On the cress germination test, 1 showed I₅₀ at 10 ppm. The other eight compounds in the fraction containing 1 on silica gel chromatography were also identified. Compounds(2) and (3) are regarded as phloroglucinol metabolites characteristic of the Eucalyptus species. The knowncompound (4) may be a good taxonomical marker for E. pulverulenta, and (5)-(9) are possibly commonmetabolites of Eucalyptus.

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Nine mutant strains defective in flocculating abilities were derived from the flocculating parent Pseudomonas strain C-120. Mutations in flocculating ability did not influence the rate and extent of cell growth. Amongthem, six strains which did not form floes at all completely lacked DNAbinding activity. Other mutant strains formed floes to a lesser extent as compared with the parent. Cell envelopes and SDS-extracted envelopes prepared from the parent strain, but not from nonflocculating mutant strains, held DNA-binding activities, indicating that DNA-binding activities of cell envelopes and SDS-extracted envelopes represented that of the wild type cells responsible for flocculation. DNA-binding activities of cell envelopes were abolished by treating with proteases, suggesting that the DNAbinding factor is a proteinaceous component. Susceptibility of DNAbinding activities of SDS-extracted envelopes to 2, 4, 6-trinitrobenzene sulfonic acid or at high temperatures supported this assumption. Although cell envelopes prepared from the parent cells and mutant cells were subjected to SDS-polyacrylamide gel electrophoresis, no differences in protein composition were observed.

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S-(N-Methylthiocarbamoyl)-D- and L-cysteine (MTCC)are new irreversible inhibitors of the amino acid racemase from Pseudomonas putida. Interactions between d- or l-MTCCand purified amino acid racemase were investigated.
The racemase catalyzes not only racemization reactions of d- and L-MTCCbut also their α, β-elimination reactions with concomitant inactivation. This inactivation exhibits the characteristics of suicide inhibition, i.e., pseudo-first order kinetics, irreversibility, stoichiometric labeling of active enzyme by the C₃ chain derived from MTCC, and protection by substrate.

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p-Hydroxybenzoic acid was newly isolated from Pinus densiflora pollen as a pollen growth inhibitor. The inhibitory effects of p-hydroxybenzoic acid on pollen germination and pollen tube elongation in four species were tested. Somephysiological properties of p-hydroxybenzoic acid and benzoic acid, the latter was isolated previously from P. densiflora pollen, were studied. The inhibitory activity of these acids increased progressively as the pHof the mediumwas lowered in the range of pH 4-7, in which pollen grains of Camellia japonica germinated well on the control medium. The inhibition by those compounds was reversed when the pollen grains were transferred to an inhibitor-free medium.
The structure-activity relationship of substituted benzoic acids was studied, and it was observed that the inhibitory activity was correlated to the substituent constant π(hydrophobic parameter).

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To compare the gene expression of the alkalophilic Bacillus penicillinase in Escherichia coli and Bacillus subtilis, we constructed a shuttle plasmid, pSAP21, from PUBHOand pEAPl containing pMB9and the penicillinase gene of alkalophilic Bacillus No. 170. When pSAP21 was transformed in E. coli, ampicillin resistant transformants (20μg/ml) could be obtained by direct selection. The penicillinase gene was also expressed in B. subtilis carrying pSAP21. Although an ampicillin resistant transformant could not be obtained directly in B. subtilis, kanamycin resistant transformants carrying pSAP21 exhibited ampicillin resistance (10μg/ml) with the replica method. Most of the penicillinase produced was found in the culture media of E. coli and B. subtilis. The penicillinase produced by E. coli carrying pSAP21 did not decrease on prolonged cultivation. On the other hand, the penicillinase produced by B. subtilis carrying pSAP21 became maximumafter 20 hours cultivation and then decreased rapidly.

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A polysaccharide containing L-arabinose, D-mannose, D-galactose, and D-glucuronic acid residues in the molar ratio of 46.9:26.0: 3.9:23.2 was isolated from the extracellular polysaccharides of suspension-cultured tobacco cells by ion-exchange chromatography and barium hydroxide precipitation. Structural studies were performed by methylation analysis, ¹³C-NMR spectroscopy, partial hydrolysis with acid, and carboxyl-reduction. From those experiments, a structure for the polysaccharide is proposed.

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The distribution of major inorganic and organic components (Ca, PO₄, Na, Mg, Sr, K, lipid and protein) and their age-related changes were investigated in various bones of striped dolphin, Stenella coeruleoalba.
Significant differences were observed betweenthe componentconcentrations of the compact and cancellous bones: the former was high in concentrations of Ca, PO₄, Na, Mgand Sr, while the latter was high in moisture, lipid, protein and K concentrations, and particularly high in lipid contents of the skull and caudal vertebrae. Nosignificant difference was found in the composition of Ca, PO₄, Na, Mgand Sr in various bones of both the immature and the mature dolphins. The skull of the fetus, and the tympano-periotic bones in particular, showed a higher accumulation of Ca and a lower accumulation of Na, Mgand Sr compared with that of the vertebrae and ribs.
Significant differences of the componentconcentrations in the bones were observed between the fetus and the adult: the concentration of moisture and K was high in the former, while other components were high in the latter, and their concentrations varied widely during the fetal and caff periods during rapid bone growth. However, the concentrations of lipid, protein and Sr showed specific age-related changes. In particular, the concentration of Sr increased markedly during the fetal and pup periods, then decreased with age until 8 yr and thereafter increased with age.
Based on these results, the part(s) of the bone most suitable for research and investigation are also discussed, the 10th dorsal vertebra emerging as the most representative bone of the total skelton for measuring the concentration of inorganic and organic components.

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Antlermicin A is a new antitumor antibiotic which inhibits growth of Bacillus subtilis strongly. As uridine incorporation into the TCAinsoluble fraction of Bacillus subtilis was inhibited severely, it was suggested that antlermicin A inhibited RNAsynthesis. Both syntheses ofuridine and uridine nucleotides were not inhibited and furthermore, accumulation of uridine nucleotides was observed in the presence of antlermicin A. The RNApolymerase reaction in a cell-free system was inhibited significantly only at a high concentration of this antibiotic.

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A simple reliable bioassay method has been developed to examine feeding preferences of a young abalone, Haliotis discus. Methanol extracts of several algae, green, brown, and red ones, showed feeding-stimulating activity to a large or small extent on the abalone. This procedure proved to be applicable for the isolation of the phagostimulants from the algal extracts.

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A phosphorylation system for formation of ATP from AMPby Zymolyase-treated cells of Candida boidinii (Kloeckera sp.) No. 2201 was developed as an ATP production process. This system was shown to be an energy conversion system, from a reduced C₁-compoundto ATP through reduction of NAD⁺ and oxidative phosphorylation but not substrate level phosphorylation, together with phosphorylation of AMPto ADP.
Reaction conditions for the ATP production were optimized in respect of substrate and coenzymeconcentrations, pHand temperature, osmotic pressure, and oxygen supply. Underthe optimal conditions, 26mM(13 g/liter) and 8.5 dim (4g/liter) of ATP were produced with methanol and formate as C₁-substrate, respectively.

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The mechanism of moisture transfer into the cured tobacco leaf was investigated in connection with the moistening processes during cigarette manufacturing. The moisture was sorbed through three pathways: through the upper epidermis, lower epidermis and the cut face. For laminar tobacco larger than about 5.0mmin width, most moisture was sorbed through the epidermes, with nearly equal flux through the upper and lower epidermes. The permeability of the culticular layer was the limiting factor to moisture transfer rate into the cured laminar tobacco through the epidermis, and the moisture transfer through the stomata was negligible as comparedwith that through the cuticular layer. An empirical kinetic model is presented to describe the entire moisture sorption process through cured tobacco epidermis, together with the values of the parameters involved. Rational moisture control of the cured laminar tobacco will be possible on the basis of this analysis.

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Purification of nicotinate phosphoribosyltransferase (NPRTase, EC 2.4.2. 1 1) from hog liver and some of its properties were investigated. Purified enzyme was found to be homogeneous by the criterion of polyacrylamide gel disc electrophoresis and to have a molecular weight of about 120, 000. The subunit molecular weight was found to be 64, 000, using SDS polyacrylamide gel disc electrophoresis. The optimum pH and isoelectric point of the enzyme were 7.3-7.4 and 4.8, respectively. Mn²⁺, Co²⁺, and Mg²⁺were effective in meeting the NPRTaserequirement for a divalent cation. ATPhad a stimulative effect on the enzymeactivity in the presence of Mg²⁺, on the other hand, in the presence of Mn²⁺, ATPhad an inhibitory effect on the enzyme activity. Of the purine nucleotides examined, only ATPstimulated NPRTase activity, and GTPdid not. On the contrary, all other nucleotides inhibited the activity. Nicotinate mononucleotide, which is a reaction product, inhibited NPRTaseactivity. Amongthe nicotinic acid analogues tested, only pyrazine-2- carboxylic acid inhibited the activity. Nicotinamide, quinolinic acid, adenine, and hypoxanthine were not phosphoribosylated by NPRTase. Incubation of NPRTase with SH-modifying reagents caused loss of NPRTaseactivity.

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Nicotinate phosphoribosyltransferase (NPRTase, EC 2.4.2. 1 1) purified from hog liver was stimulated by orthophosphate. This stimulation was independent of ATPwhich activated this enzyme by increasing the velocity and lowering the Km values for nicotinic acid and 5- phosphoribosyl-1-pyrophosphate (PRPP). This independent stimulation by orthophosphate and activation by ATPwere true of hog liver or rat liver homogenate as well as the purified hog liver NPRTase, showing that there maybe some physiological role of these compounds in vivo. The Ka value for ATPwas about 1.2mM. At a physiological concentration of PRPP, it was mainly used by quinolinate phosphoribosyltransferase (QPRTase, EC 2.4.2.19) in the reconstituted assay conditions of NPRTase and QPRTase if the ATP concentration was lower. But if the ATP concentration was higher, PRPP was used by both QPRTase and NPRTase. Therefore, ATP was found to play a very important role for the biosynthesis of NAD via the salvage pathway.

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A new and efficient synthesis of γ-homocyclogeranial (4), γ-dihydroionone (3) and their derivatives, 5, 6, 7 and 8, volatile components of ambergris, is described. Their compoundswere synthesized via Claisen rearrangement of (3, 3-dimethylcyclohexenyl)methyl vinyl ether (14).

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Properties of N-acetylmuramidase of Streptomyces rutgersensis H-46 were investigated using cell walls and peptidoglycan of Streptococcus feacalis as substrates. Peptidoglycan was prepared from cell walls by extracting polysaccharide, teichoic acid and protein with TCAand SDS. When cell walls and peptidoglycan were used as substrate for the enzyme, the enzyme reaction proceeded following second and zero order kinetics, respectively. The optimum pH for cell walls was 6.0, while that for peptidoglycan was 3.5. The enzyme activity was observed even at pH 1.3. It was found that the enzymereaction was strongly affected by ionic strength of the reaction mixture. Ionic strengths of 0.015 and 0.6 were found to be optimum when cell walls and peptidoglycan were used as substrate, respectively. An eminent difference in the extent of inhibition with metal ions was observed when the substrate of cell walls was replaced by peptidoglycan. It was considered that this difference was due to the presence of polysaccharide and/or teichoic acid in the cell wall preparation.
The respective apparent Km value and maximumreaction velocity of the enzyme for peptidoglycan of S. faecalis were calculated to be 22.0μg/ml and 0.067 absorbance/min.

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A new type of mutant unable to reduce 2, 3, 5-triphenyltetrazolium chloride (TTC) was isolated from miitagenized cells of Saccharomyces cerevisiae. These TTC^- mutants were respirationcompetent although most TTC^- mutants reported so far are respiration-deficient. The isolated mutants were also uracil auxotrophic, and genetic analysis indicated that a recessive mutation took place on a single gene tightly linked to the ura2 gene or in the ura2 gene in all these mutants. Moreover, we found that authentic ura mutants (ura1 to uraS) also exhibited the TTC^- phenotype while other auxotrophic mutants tested were of the TTC⁺ phenotype. These findings suggest that yeast cells have a TTCreduction system related to uracil metabolism besides that related to respiratory potential.

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The effects of aeration-agitation conditions and mediumcomposition on colistin fermentation were investigated with 5 liter-jar fermentors, using a medium containing aspartic acid. Since the high viscosity of the culture at 28°C lowered the aeration-agitation effect, a lower viscous culture at 32°C was used. The aeration-agitation conditions on a 5 liter-jar scale were determined with agitation. Although an increase of sugar concentration improved colistin production, an increase of broth viscosity or agitation speed limited colistin production. On the other hand, ammoniumnitrogen (NH₄-N) was found out to control not only the optimum ratio of carbon to nitrogen for colistin production but the broth viscosity. The optimum ratio of sugar (as glucose) to NH₄-N in the colistin fermentation was about 10 : 4. The optimumphosphate concentration for colistin production was independent of the agitation speed.
Bacillus polymyxa var. KY-7584 produced 71, 000u/ml of colistin in the modified medium containing the optimum levels of sugar and NH₄-Nat 32°C. This titer corresponded to an increment of about 30% compared with the maximumtiter in the reference medium at 28°C (55, 500u/ml), and also was about five times as much as that in Morido's medium (14, 800u/ml) used as the basal medium.

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In Euglena gracilis arginine deiminase was located in the mitochondrial matrix. The highly purified enzyme required Co²⁺ for the enzyme reaction with the Km value of 0.23mM, and its optimum pH was 9.7 to 10.3. The molecular weight of the native enzyme protein was 87, 000 by gel filtration, and SDS-acrylamide gel electrophoresis showed that the enzyme consisted of two identical subunits with a molecular weight of 48, 000. Euglena arginine deiminase was inhibited by sulfhydryl inhibitors, indicating that a sulfhydryl group is involved in the active center of the enzyme. It exhibited negative cooperativity in binding with arginine. L-α-amino-β-guanidinopropionate, D-arginine, and L-homoarginine strongly inhibited the enzyme while β-guanidinopropionate, γ-guanidinobutyrate, and guanidinosuccinate did not. Considerable inhibition was also observed with citrulline and ornithine. Wediscuss the effects of the unique properties of the Euglena arginine deiminase on the regulation of arginine metabolism in this protozoon.

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A series of N-benzylbenzenesulfonamides were synthesized and their biological activities were tested. Amongthese compounds, N-(2, 3-epoxypropyl)-N-(α-methylbenzyl)benzenesulfonamide derivatives were found to be the most active against barnyardgrass and to have physiological selectivity between barnyardgrass and rice plants.

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We isolated a mutant strain of Candida lipolytica which produces long-chain fatty acids in the culture medium. The procedure for the isolation of the mutant consisted of two steps: the first was the screening of strains which exhibited a low cellular density by Percoll density gradient centrifugation, and the second was the screening of strains which were capable of supporting the growth of fatty acid auxotrophic cells layered on the mutant colonies. One of the mutant strains produced more than 1 mgof fatty acids per ml of the mediumunder optimal conditions. The excreted fatty acids were mainly palmitic and stearic acids in the nonesterified form.

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The folate-hydrolyzing enzyme was purified 49-fold from the crude extract of Crithidia fasciculata ATCC12857 by heat treatment, column chromatographies on DEAE-cellulose and Sephadex G-200, and preparative polyacrylamide gel electrophoresis. The final preparation was electrophoretically homogeneous. The enzymehad a molecular weight of 200, 000 daltons and consisted of 4 identical subunits of which the molecular weight was about 51, 000 daltons. The enzyme hydrolyzed aminopterin, methotrexate, and PABGmore effectively than folate. The enzyme hydrolyzed the reduced folates, dihydrofolate and 10-formyltetrahydrofolate, more weakly than folate. The enzyme did not act on pteroly-γ, γ-diglutamylglutamate. The optimum pH for the reaction with each substrate described above was 7.0. Km values for folate, methotrexate, aminopterin, and PABGwere 0.13, 0.46, 0.40, and 0.43mM, respectively. The enzyme activity was inhibited by 2-mercaptoethanol, PCMB, chelating reagents such as α, α', α''-tripyridyl and bathophenanthroline, divalent cations such as Hg²⁺, Cu²⁺, Cd²⁺, Pb²⁺, and Zn²⁺, and by pyrophosphate and orthophosphate.

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Globomycin inhibited the incorporation of [¹⁴C]diaminopimeric acid (Dap) into the cold 5% TCAinsoluble fraction of Escherichia coli H2143at higher concentrations than the minimum inhibitory concentration (MIC).
One-sixth or -seventh molecules of the lipoprotein were found per one molecule of N-acetyl glucosamine (GlucNAc) or Dap in globomycin-treated cells as compared with one-twelfth or -thirteenth molecules in normal cells. Amongglobomycin-resistant cells isolated, one-tenth were lipoprotein-less mutants and they showed a slightly swollen form and leaked RNase into the medium. It was interesting that spheroplast formation of the mutants in the presence of the antibiotic was not observed even at a high concentration.

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Wehave tested various chemicals for their modifying effects on the behavior of the pine woodnematode. Several compounds containing the oleyl group, i.e., ethylene glycol monooleate, 1-monoolein, oleic acid and oleyl alcohol were attractive.¹⁾ Allyl isothiocyanate, naringenin, 1-tyrosine, 1-tryptophan and calcium chloride were also attractive, while capsaicin and magnesium chloride exhibited repellency.²⁾
As a continuation of these works, we tested behavioral responses of the nematode to terpenes. The results are presented in this paper.

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The possibility of preparing pyrroloquinoline quinone (PQQ), a novel coenzyme, by a microbial method was proposed for the first time. PQQwas formed and accumulated in the culture mediumof various microorganisms. Of the tested strains, somemethylotrophs were most favorable for PQQ production and more than 10μg/ml ofPQQ was found in the culture mediumafter 2 days incubation. An attempt at the isolation and purification of PQQwas made successfully and spectral evidence was obtained suggesting that the purified PQQ was identical with authentic PQQ. The spectral similarity of PQQ to the chromophores isolated from methylamine dehydrogenase and copper containing amineoxidases wasalso indicated.

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