An acid protease inhibitor (S-PI) accelerated the growth of Rhodotorula glutinis. This acceleration of the growth was observed only when the pH of the culture fluid lowered during the cultivation, but was not observed when the pH of the culture fluid was adjusted to 2.8 with NaOH. The increase in number of cells was closely related to cell deaths. The cell deaths were observed in an active growing state but not in a resting state. S-PI increased the DNA, RNA and protein content in the cell and decreased the lipid, especially the phos-pholipid content. When the yeast was cultured in an acidic medium having an initial pH of 1.8 in the presence of S-PI, the decrease of the phospholipid in the cell preceded, followed by the leakage of potassium ion, UV absorbing materials and free pool amino acid from the cell which were accompanied with the cell death. On the basis of these results, physiological changes occuring in the yeast cell are discussed.

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Phthalate esters, such as di-2-ethyl hexyl phthalate (DEHP) and di-n-butyl phthalate (DBP), were efficiently removed from wastewater by inoculating viable cells of Nocardia erythropolis, a bacterium capable of rapidly degrading phthalate esters, in activated sludge. When the wastewater containing 1500ppm of DEHP was treated with the activated sludge inoculated with Nocardia erythropolis, the DEHP was found to be removed at a rate of 98.2% in 1 day and to be gas-chromatographically free on and after the 3rd day. Activated sludges, in particular, when high concentration of substances was used, were efficiently prevented from deflocculation of sludge by inoculation of Nocardia erythropolis, and moreover, the deflocked sludge was restored and recovered by the addition of Nocardia erythropolis.

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The information presented in this part is centred on two issues: first, the effect of zero-energy (maintenance) and negative-energy balance (submaintenance) feeding of young lambs on their carcass characteristics, body composition and certain non-carcass parts; second, the ability of the depleted (submaintenance) lambs to resume growth at an enhanced rate following realimentation, and so reach normal adult size and proportions. The effect of nutritional stress seems to be differential on various body components. In some it merely slowed down the rate of growth; in others it stopped or even reversed the growth process.

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The effect of maintenance (zero-energy balance) and submaintenance (negative-energy balance) feeding, and of subsequent compensatory growth (repletion) on chemical and bio-chemical aspects of lamb L. dorsi muscle were studied. Maintenance and submaintenance feedings were found to cause marked decrease in the contents of lipid, sarcoplasmic proteins and free amino acids nitrogen, while increase in water and stroma proteins (including alkali-soluble and alkali-insoluble stroma fractions) of muscle. Besides the amount, the physico-chemical nature of stroma (connective tissue) was also changed by nutritional stress, where by the ‘acid-stable’ cross-linkages in the structure increased significantly. The myofibrillar pro-teins, however, decreased only in the case of submaintenance feeding regime.
Almost all the chemical characteristics of muscle from repleted lambs were statistically comparable to those of respective control. However, myofibrillar proteins (on a fat-free, dry weight basis) were slightly less and stroma proteins were slightly high with relatively more ‘acid-stable’ cross-linkages in muscle from the lambs which experienced compensatory growth. In the light of these results the previous concepts of ‘labile proteins reserve’ and ‘fixed’ proteins in muscle have also come under secrutiny.

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The effect of maintenance (zero-energy balance) and submaintenance (negative-energy balance) and of subsequent compensatory growth (repletion) on the micro- and ultrastructure of L. dorsi muscle from young lambs was investigated. This study showed that fibre diameter and sarcomere length did not change significantly due to maintenance feeding but submainten-ance feeding caused a marked decreased in these parameters. The microscopic appearance of collagen was a dense, course fibrillar type, and occurred in thicker bundles in the muscle of under-fed lambs. However, the nature elastin was similar in all lambs.
The under-feeding also caused pronounced reduction in the amount of glycogen granules and the number of mitochomdria in muscle. The sarcoplasmic reticulum and T-system did not seem to be related to the nutritional status of the animals. The myofibrils remained normal during maintenance feeding, whereas submaintenance feeding resulted in some degen-eration of actin and myosin filaments. However, there was no difference in the sarcomere periodicity or banding pattern of the normal portions of degenerated myofibrils.
The general features and appearance of fibres, and the fine structure of myofibrils and cellular components of the muscle from the replenished lambs became identical to that of normally grown lambs at the same age. The collagen, however, was still moderately dense and the fat cells were small in the repleted lambs.

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The effect of maintenance (zero-energy balance) and submaintenance (negative-energy balance) feeding, and of subsequent compensatory growth (repletion) on the quality of lambs meat was studied. It was observed that maintenance and submaintenance feeding markedly decrease the objective and subjective criteria of tenderness of meat in young lambs. The judges, opinion however, varied so far as the magnitude of reduction in tenderness was con-cerned. The juiciness and flavour of meat were not affected by nutritional stress. The first-and second-order interactions between different variables clearly supported these observations.
The difference in the ultimate pH value of muscle from lambs, reared on different nutri-tional planes, was reflected in the pH value of cooked meat. The ‘free’ and total water content tended to be high in cooked meat from underfed lambs, but the amount of ‘bound’ water was identical in meat from all lambs. The difference in the tenderness of meat from replenished and control lambs was not apparent, suggesting that underfed young lambs, following an adequate period of compensatory growth, produce meat of the same quality or only marginally different from normally grown lambs of the same age.

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Galactolipase (galactolipid acyl hydrolase, EC 3.1.1.26) was purified 147-fold in good yield (91%) from rice bran by affinity chromatography, in which the enzyme was adsorbed on a palmitoylated gauze column at pH 5.5 and then was eluted with a buffer solution con-taining a detergent such as sodium deoxycholate or Triton X-100 at pH 8.0. The preparation obtained was further purified by gel filtration on a Sephadex G-100 column and isoelectric focusing. After electrophoresis, the enzyme separated into four components with different isoelectric points. It seems that galactolipase in rice bran exists in multiple forms. The major component (G-2) with isoelectric point of 7.3, one of them, was purified 268-fold and electro-phoretically homogeneous. The enzyme (G-2) hydrolyzed rapidly galactolipid and also slowly phospholipid, but hardly triglyceride.

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Fractionation of the crude prophenoloxidase solution from prepupae of housefly, Musca domestica vicina Maquart, was carried out. The soluble fraction of 40% saturation of am-monium sulfate contained a certain factor being able to inhibit the activation of prophe-noloxidase A with natural activator from aged pupae. The factor seemed to be a protein and was named Factor N tentatively.
Purification of Factor N by gel filtration on Sephadex G-75 and sucrose density gradient ultracentrifugation resulted in an 18.2% of the yield of the activity and a 21.8-fold increase in the specific activity. The purified preparation of Fractor N had a sedimentation constant of 5.4 S.

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Penicillinase from an alkalophilic strain, Bacillus No. 170, was separated into two com-ponents, penicillinases I and II, by CM-cellulose chromatography. Penicillinase II was rather stable at high pH, and was thermolabile than penicillinase I. Both penicillinases I and II had similar substrates specificity; penicillin G, ampicillin, carbenicillin, and cephaloridine were rapidly hydrolyzed. The molecular weights of penicillinases I and II were 34, 000 and 12, 500 respectively. The two penicillinases were little inhibited by SH-reagents. These pro-perties of the two enzymes differed from those of the enzymes reported previously, especially in the substrates specificity and the molecular weight.

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Three forms of α-glucosidase have been isolated from 5-day-old green gram (Phaseolus vidissimus Ten.) seedlings, by a procedure including fractionation with ammonium sulfate and polyethylene glycol 6000, DEAE-cellulose column chromatography, SP-Sephadex column chromatography, preparative gel electrofocusing and preparative disc gel electrophoresis. The α-glucosidases isolated were designated as α-glucosidase I, α-glucosidase II-1 and a-glucosidase 11-2. They were homogeneous on polyacrylamide disc gel electrophoresis. Their molecular weights were 145, 000, 105, 000 and 65, 000, respectively. The three enzymes hydrolyzed maltose, maltotriose, phenyl α-maltoside, amylose and soluble starch liberating glucose, but did not act on sucrose. Their enzymes hydrolyzed phenyl α-maltoside into glucose and phenyl α-glucoside. They hydrolyzed amylose liberating α-glucose. Malto-triose was the main α-glucosyltransfer product formed from maltose by the three α-gluco-sidases.

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The relationship between L-lysine production and biotin levels in culture medium was investigated in Brevibacterium lactofermentum. Strain AJ3799 accumulated 34mg/ml and 42mg/ml of L-lysine•HCl in the presence of 50μg/liter and 500μg/liter, respectively, of biotin in culture medium. This increase in L-lysine production was observed with various kinds of lysine producers and also with resting cells grown in biotin poor medium. Biotin functioned as an effector only when glucose or pyruvate was used as a substrate. And this effect was accompanied with reduction of carbon dioxide liberation, as well as decreased accumulation of L-alanine, L-valine and L-leucine. On the other hand, penicillin and some surfactants had no effect on the function of biotin. These data suggest a significant new role for biotin in Brev. lactofermentum.

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Nondialyzable ¹⁵N-melanoidin was prepared from a model system of glucose and ¹⁵N-glycine, and the growth response of rats fed with the dietary melanoidin was examined. Meas-urement of the excreted melanoidin by ¹⁵N-balance revealed that 76% of the dietary mela-noidin was excreted in the feces. Measurement of brown pigments in aqueous extract from the feces and in the urine by colorimetry indicated that 65% of the dietary melanoidin was excreted in the feces but none in the urine. It is speculated from the gel filtration chromato-graphy of melanoidin that low molecular components of the dietary melanoidin were degraded into less or non-colorant materials through digestion and absorption in the intestines and that part of degraded melanoidin was retained by rats. Both low molecular components and reducing value of the fecal melanoidin were smaller than those of the original melanoidin.
Growth response, protein digestibility and lipid digestibility of the rats fed with the dietary melanoidin were not significantly different from those of the control.

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The sequences of three Asn-carbohydrates, IIa, Asn(GlcNAc)₂-(Man)₉; IIb, Asn(GlcNAc)₂(Man)₈; and IIc, Asn(GlcNAc)₂(Man)₇ isolated from the pronase digest of a 7S soybean protein (β-conglycinin) were investigated. In each case, methylation analysis of the Asn-carbohydrates gave 3, 6-di-O-methyl derivative from the N-acetyl-glucosamine residue, and 2, 3, 4, 6-tetra-O-methyl, 3, 4, 6-tri-O-methyl and 2, 4-di-O-methyl derivatives from the mannose residues. The first Smith degradation of all the Asn-carbohydrates gave Asn(GlcNAc)₂-(Man)₂ and the second degradation afforded Asn(GlcNAe)₂. Partial acetolysis of the Asn-carbohydrates followed by deacetylation yielded mannobiose and mannotriose from, Ila, and mannose and mannobiose from lib and IIc. From these results, their possible structures are discussed.

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In the present study to examine the relative nutritional functions of amino acids in animal bodies, the effects of both deficient and excess levels of 9 individual L-amino acids were in-vestigated by the carcass retention method as well as by growth assay. The result indicated that these amino acids can be classified into at least four different groups by their effects on the retention to consumption relationships of protein and energy; one for arginine and iso-leucine, one for lysine, one for tryptophan and one for valine, leucine, threonine, methionine and phenylalanine.

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Phospholipase Al, purified from the culture filtrate of Corticium centrifugum, was found to possess lysophospholipase 1 activity. The isoelectric point was pH 3.3, and the molecular weight was about 26, 800. Both enzyme activities had their pH optimum between 4.0 and 4.5 and their pH stability between 6.0 and 8.0, and were heat-unstable. Both were inhibited by p-diazobenzenesulfonic acid and N-bromosuccinimide. Although ether, 1-propanol and Triton X-100 stimulated phospholipase AI activity, these substances showed an inhibitory effect against lysophospholipase I activity. Phospholipase A_l activity was almost completely inhibited by Fe²⁺, Fe³⁺ and Al³⁺, but the inhibition was lessened by the presence of Triton X-100. Lysophospholipase 1 activity was inhibited by Hg²⁺, Fe³⁺ and Al³⁺. The mode of inhibition by Fe³⁺ against lysophospholipase 1 activity was apparently an uncompetitive type. Phospholipase Ai hydrolyzed various phospholipids, but not triolein.

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Pyruvate kinase (EC 2.7.1.40) was partially purified from an extreme thermophile, Thermos thermophilus HB8, and its enzymatic properties were studied. The enzyme showed high thermostability and was also stable at lower temperatures. Divalent metal ions such as Co²⁺, Mn²⁺, and Mg²⁺ were required for activity. The enzyme showed optimum pH of 5.5_??_6.0 and sigmoidal rate curves for both substrates PEP and ADP at the growth temperature, 75°C. UDP and GDP also acted as nucleotide substrates. The enzyme was activated by the glycolytic intermediates in the following order: glucose 6-phosphate>fructose 6-phosphate>dihydroxy-acetone phosphate>glyceraldehyde 3-phosphate, fructose 1, 6-bisphosphate. The enzyme, on the contrary, was inhibited by ATP, glycerate 3-phosphate, glycerate 2-phosphate, and P₁. AMP, 20 amino acids, and several intermediates of the tricarboxylic acid cycle were noneffective. The in vivo regulatory functions of the enzyme were discussed from these findings.

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The in vivo concentrations of metabolites and the level of enzymes were measured to elucidate the regulatory mechanism by phosphoenolpyruvate of glycolysis-gluconeogenesis in an extreme thermophile, Thermus thermophilus HB8. Glucose 1-phosphate, glucose 6-phosphate, fructose 6-phosphate, and fructose 1, 6-bisphosphate were low, and phosphoenol-pyruvate was high in the cells growing on polypeptone-yeast extract (PY cells). On the contrary, phosphoenolpyruvate was low and hexose phosphates were high in the cells growing on glucose-polypeptone-yeast extract (GPY cells). The difference in the values of adenylate energy charge was not observed between PY and GPY cells. Among various enzymes, phosphofructokinase and fructose 1, 6-bisphosphatase level changed markedly; the former was high in GPY cells and the latter in PY cells. It is reasonably considered that PY cells may turn on gluconeogenesis and GPY cells on glycolysis. The in vivo regulatory functions of key enzymes, phosphofructokinase, fructose 1, 6-bisphosphatase, and pyruvate kinase, and the important roles of phosphoenolpyruvate and fructose 6-phosphate were discussed from these findings.

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Reaction of the reduced ricin D with N, N'-o-phenylenedimaleimide produced a cross-linked ricin D which could not be split into its constituent polypeptide chains with reducing reagents. This cross-linked ricin D was as stable as native ricin D and retained the full cytoagglutinating activity, while the toxicity to mice and cultured cells was remarkably de-creased.
The cross-linked ricin D was incorporated into cells in the same manner as native ricin D, but was not degraded by incubation with the lysate of rabbit reticulocytes. From these results, it was inferred that ricin D is split into its constituent polypeptide chains by reduction of the inter-chain disulfide bond in cytoplasm and thus its toxic action is elicited.

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Starting from 7-hydroxy-6-methoxy-indole (III) PDE-II (II), a new inhibitor of cyclic adenosine 3', 5'-monophosphate phosphodiesterase and the first substance which has 1, 2-dihydro-3H-pyrrolo[3, 2-e]indole skelton, was synthesized in eight steps. The key inter-mediate, 1-acetyl-5-amino-2, 3-dihydro-7-hydroxy-6-methoxy-indole (VIII), carring necessary substituents was obtained from III in five steps. Coupling of the diazoniumsalt of VIII with ethyl 2-acetylpropionate followed by acid catalized cyclization and alkaline hydrolysis afforded II.

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PDE-I (I), a new inhibitor of cyclic adenosine-3', 5'-monophosphate phosphodiesterase, was synthesized in seven steps of reactions from 1-acetyl-2, 3-dihydro-7-hydroxy-6-methoxy-5-nitro indole (III) via the key intermediate, 5-amino-1-carbamoyl-2, 3-dihydro-7-hydroxy-6-methoxy indole (VII), which has the hydroindole skelton and the sites for the introduction of the pyrrole moiety necessary for the preparation of 1.

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A lipolytic acyl-hydrolase was purified about 220-fold from the homogenate of the leaves of Phaseolus vulgaris L. cv. Kurodane-kinugasa by acetone precipitation, affinity chromato-graphy on a palmitoylated gauze column and isoelectric focusing. The purified enzyme showed a single protein band by polyacrylamide gel disc electrophoresis. The enzyme had an isoelectric point of 4.4 and a molecular weight of about 90, 000. It had pH optima of 5.5 and 6.5, and Km values of 0.24 and 0.53mm for monogalactosyldiacylglycerol and phos-phatidylcholine, respectively. The pH dependences were changed by Triton X-100. No separation of these two hydrolyzing activities were achieved, and the ratio of the specific activity of galactolipase to that of phospholipase (about 3/1) remained constant throughout the purification procedures. Both the activities changed in parallel with each other by the addition of reagents and by heat treatment. The enzyme clearly catalyzed the deacylation of the several classes of glyco- and phospholipids. These results suggest that a single enzyme is responsible for both the activities.

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Arthrobacter oxydans (PG21-1) which was isolated from soil preferably assimilated 1, 2-propanediol and produced remarkable amount of lactic acid. Cultural conditions for lactic acid production from 1, 2-propanediol were studied using a 15 liter jar fermentor. Optimum pH and urea concentration for the production of lactic acid were 8.0 and 0.3%, respectively. Under these conditions, the yield of lactic acid was 17.8g/liter in 7 day cultivation. About 70% of the utilized 1, 2-propanediol was converted to lactic acid. The production of lactic acid by resting cells was also investigated. Resting cells of Arthrobacter oxydans showed a high activity to produce lactic acid at alkaline pH and the amount of the acid reached to 10.2g/liter in 12 hr incubation. The accumulation of lactic acid at alkaline side was considered to due to the strong suppression of the degradation of lactic acid.

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Broad bean protein was fractionated into four fractions, so-called 2 S, 7 S, 11 S and 15 S components, by sucrose density gradient centrifugation. 11 S component obtained was homogeneous as judged by polyacrylamide gel electrophoresis. 15 S component was found to be a dimeric form of 11 S component. Molecular weights of 11 S and 15 S components were 319, 000 and 599, 000, respectively. 11 S component consisted of at least four kinds of acidic subunits with molecular weights of 36, 000, 49, 000 and 51, 000 and three kinds of basic subunits with molecular weights of 19, 000, 20, 500 and 23, 000. The acidic subunits and the basic subunits were present in equimolar amounts in 11 S component. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the absence of reducing reagent suggests that 11 S component contains at least three kinds of intermediary subunits with molecular weights of 48, 000, 59, 800 and 61, 700.

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Weanling rats were fed a 10% casein containing 5% tyrosine (1OC5T) diet supplemented either with 20% casein or with 0.66% methionine plus 0.90% threonine for 7 days ad libitum, and then the activities of liver tyrosine-catabolizing enzymes: tyrosine (Tyr) transaminase; p-hydroxyphenylpyruvate (pHPP) hydroxylase; and homogentisate oxidase; were determined sequentially at various times during 24-hr period. The mean activity of Tyr transaminase was elevated by feeding high tyrosine diets, except the methionine and threonine supplemented diet. The mean activity of pHPP hydroxylase was depressed by high tyrosine but was reversed by the addition of extra casein or methionine and threonine, and the ratio of Tyr transaminase and pHPP hydroxylase activities in rats consuming the 1OC5T diet was remarkably elevated. The mean activity of homogentisate oxidase was somewhat depressed in rats fed the lOC5T diet, but was not affected by the additional casein or methionine and threonine supplements. In all dietary groups, Tyr transaminase showed a daily variation which included a maximal peak during darkness, whereas pHPP hydroxylase and homogentisate oxidase activities did not show so much clear daily variation. The high concentration of free tyrosine in body was markedly decreased by the addition of casein or methionine and threonine. It is sug-gested that the beneficial effect of extra casein or methionine and threonine supplementation on tyrosine toxicity may be due to the improvement of nutritional quality and the increase of the capacity of tyrosine metabolism by the increasing liver pHPP hydroxylase.

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The structure of amastatin was elucidated to be [(2S, 3R)-3-amino-2-hydroxy-5-methyl-hexanoyl]-L-valyl-L-valyl-L-aspartic acid, and was confirmed by chemical synthesis.

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The changes in the lipid components of tobacco leaves during flue-curing were investigated. The contents of total fatty acid methyl esters and linolenate decreased considerably, though a temporary increase was observed at the early period of the yellowing stage. The amounts of digalactosyl diglyceride (DGDG), monogalactosyl diglyceride (MGDG), sulfoquinovosyl diglyceride and phosphatidyl glycerol decreased markedly while phosphatidyl inositol, phos-phatidyl serine and phosphatidyl choline were relatively resistant to the degradation process. MGDG and DGDG were found to have high proportions of linolenate while most phos-pholipids had high proportions of palmitate. Considerable decrease was observed in the ratio of linolenate in most polar lipids while the ratio of palmitate and stearate showed a significant increase.

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Laminaran was isolated from Eisenia bicyclis. On the basis of the methylation, periodate oxidation, NMR spectroscopy by ¹H and ¹³C nuclei, this glucan was shown to have a branched structure composed of (1→3)- and (1→6)-linked β-D-glucopyranose residues in the ratio 3:2. The glucan was especially characterized by comparison of its ¹³C and 1H NMR spectra with those of related compounds. The NMR investigation of the polyol polysaccharide, ob-tained by reduction after periodate oxidation of laminaran, was very useful for elucidation of the composition, structure and major sequence of the native glucan.

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The reduction rate of nitro-blue tetrazolium by superoxide anion radicals during the autoxidation of hydroxylamine (20μM) was inhibited by 67% in the presence of 5μM Cu²⁺. However, upon the addition of a cationic micelle of hexadecyltrimethylammonium bromide or a nonionic micelle of polyoxyethylene dodecyl ether, the reduction rate markedly increased with an increase of the concentration of Cu²⁺. The coexistence of 10μM Cu²⁺ and 5mM cationic or nonionic micelle accelerated this reaction about 50- or 75-fold, respectively, al-though the absence of Cu²⁺ accelerated the reaction rate only about 8.0- or 6.0-fold, respectively. On the other hand, the generation rate of nitrite during the autoxidation of hydroxylamine was increased by the addition of Cu²⁺ and decreased by the addition of the micelles. The co-existence effect of Cu²⁺ and micelles was not observed in the case of nitrite formation reaction. The microenvironmental effects on these reactions were discussed.

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The uptake of uranium by Chlorella regularis was examined by using the solution con-taining uranium only for the first step of approach to the recovery of uranium from the aqueous systems.
The uptake of uranium by C. regularis was very rapid, and was not so affected by light, temperature, and treatments with metabolic inhibitors. Eighty one percent of uranium taken up in the living cells was released by washing with EDTA solution. Seventy five percent of uranium taken up in both the living and the scalded cells was distributed in the 26, 000×g precipitate of the cell homogenate.
These results suggested that the uptake of uranium by C. regularis depended upon the physical adsorption on the cell surface, but not upon the biological activity, and that uranium in the algal cells was coupled with the ligands, which was able to be easily substituted with EDTA.

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The effect of various cations and anions on the uptake of uranium by Chlorella regularis was examined.
The uptake of uranium was hindered by phosphate and carbonate ions and was not affected by cations (sodium, potassium, ammonium, magnesium, calcium, manganese, cobalt, nickel, and zinc ions), nitrate, sulfate, and thiosulfate ions. The amounts of uranium taken up by C. regularis rapidly decreased with increasing the concentration of phosphate ion in the uranium solution. The amounts of uranium taken up by C. regularis also rapidly de-creased with increasing the concentration of sodium hydrogencarbonate in the uranium solution. The amounts of uranium taken up by C. regularis in the uranium solution con-taining 1.196×10^-3M/liter of sodium hydrogencarbonate were the largest at pH 5 and rapidly decreased in both low and high pH regions. The compositions of the chemical species of U(VI) in the carbonate solution were calculated, of which results suggested that carbonate ion formed the stable complex ions with uranyl ion, such as UO₂(CO₃)₂^2- or UO₂(CO₃)₃^4-, which were not taken up by C. regularis.
From these results, we suggested that the uranium was taken up by C. regularis as the cation form (UO₂²⁺ or UO₂OH⁺), and Chlorella cells took up uranium in exchange for their protons in analogy with some organic chelating agents.

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As the first step towards the biosynthetic studies on grayanotoxins with the aid of ¹³C isotope, the ¹³C-NMR spectra of grayanotoxin-I and III were assigned. Unambiguous assignments were achieved except for the C-9 and C-I 3 resonances in G-I by selective proton decoupling technique as well as by comparison with chemical shift values of the related com-pounds.

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Ribonucleotide reductase from Rhizobium meliloti grown on the cobalt-deficient medium containing methionine was purified about 37-fold by streptomycin treatment, ammonium sulfate fractionation and column chromatographies on 1st DEAF-cellulose, 2nd DEAE-cellulose and Sepharose 6B. In agar gel electrophoresis, the purified enzyme moved as a single protein band. In sedimentation velocity experiments and analytical gel filtration, the purified enzyme was proved to aggregate and disaggregate. The s₂₀, w of the enzyme at high concentration was about 27.1. From the intercept of the extrapolated curve line, the s₂₀, w of approximately 20 was obtained. In analytical gel filtration, the location of elution peak varied with the protein concentration placed on the column. Sodium dodecyl sulfate gel electrophoresis of the purified enzyme exhibited two bands, the molecular weights of which were estimated to be approximately 130, 000 (a major band) and 110, 000 (a minor band). The proportion of the major band to the minor band was 3:1. The pH optimum for the enzyme activity was 9.0_??_10.0. The activity was maximum at 45_??_50°C. The Km value for adenosyl-B12 was 0.77×10^-6M. The concentrations of ADP and reduced lipoic acid necessary for saturation of the activity were 0.75×10^-3M and 30×10^-3M, respectively. Ribonucleoside diphosphates were most effective as substrates.

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Minor fungal metabolites, cotylenins H and I, were isolated from the culture filtrate of an unidentified species of Cladosporium and their structures have been assigned as II and I, respectively, on the basis of the chemical and spectroscopic evidence.

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