Chitosan-like materials were extracted from five different fungal cells with NaOH and acetic acid, with the yields varying from 1.2 to 10.4% of the dry fungal cell weight. The degree of N-acetylation of the extracts measured by the colloidal titration method varied considerably depending on the individual species. By IR measurements and the Elson-Morgan method, four kinds of the extracts were characterized as chitosan while another one was not. The degree of N-acetylation and the Cu²⁺ adsorption capacity of the fungal chitosans were measured and compared with those of authentic samples with various degrees of N-acetylation, which were prepared by chemical treatment of authentic chitin and chitosan derived from Crustacea. The Cu²⁺ adsorption capacity of the fungal chitosans was higher than that of the authentic chitosan samples with similar degrees of N-acetylation and independent of the molecular weight of the chitosans from the various sources.

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An extracellular α-glucosidase was purified from the culture broth of Paecilomyces varioti AHU 9417 by a combination of precipitation with ethanol, chromatography on DEAE-Sepharose CL-6B and Bio-Gel P-150, and preparative gel electrophoresis. The enzyme migrated as a single band on polyacrylamide gel electrophoresis. The molecular weight was estimated to be 100, 000 by SDS-disc electrophoresis, and the optimum pH of activity was 4.5. The enzyme had a wide substrate specificity, as it rapidly hydrolyzed maltooligosaccharides and isomaltooligosaccharides. The ratios of V_max for maltose, isomaltose, kojibiose, nigerose, phenyl α-glucoside, maltotriose, isomaltotriose, panose, phenyl α-maltoside, and soluble starch were estimated to be 100, 72, 31, 105, 9.6, 103, 73, 47, 115, and 66, and the K_m (mM of nonreducing terminal) for these substrates were 0.40, 2.4, 1.6, 2.5, 0.23, 0.33, 4.6, 0.67, 0.24, and 4.7 mM, respectively. The enzyme is characterized by a high activity toward isomaltose.

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We treated leaves of winter wheat (Triticum aestivum L.) with cold, paraquat, or 3-amino-1, 2, 4-triazole and compared the responses. We assayed the activities of glucose-6-phosphate dehydrogenase, catalase, dehydroascorbate reductase and ascorbate free radical reductase and levels of hydrogen peroxide, glucose-6-phosphate, fructose-6-phosphate, ascorbate, dehydroascorbate, reduced and oxidized glutathione. With any of the three treatments, contents of cellular peroxides and hexose phosphates were raised. The content of ascorbate was lowered markedly by paraquat treatment, which produces active oxygen species, whereas such a decrease did not occur in other two treatments. When the plants were treated with 3-amino-1, 2, 4-triazole, which is a specific inhibitor of catalase, the content of oxidized glutathione increased severalfold. The glucose-6-phosphate dehydrogenase activity increased with all three treatments, but it decreased after glyphosate treatment, which dose not stimulate the formation of peroxides. The activities of catalase and dehydroascorbate reductase were increased by the treatment of peroxides. The activities of catalase and dehydroascorbate reductase were increased by the treatment of cold and paraquat, while 3-amino-1, 2, 4-triazole did not affect the dehydroascorbate reductase activity. The acitivity of ascorbate free radical reductase increased after treatment by paraquat only.

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Spermidine dehydrogenase found in the membrane fraction of Citrobacter freundii IFO 12681 was solubilized with Triton X-100 and further purified to homogeneity. The properties of the membrane enzyme were almost identical to those obtained from the soluble fraction of the organism with respect to molecular and catalytic properties. Thus, binding properties of the enzyme to the bacterial membrane were checked. The ratio of enzyme activity found in the soluble fraction to the membrane fraction was dependent on salt concentration during cell disruption. A hydrophobic interaction was largely involved in anchoring the enzyme to the membrane fraction. Purified spermidine dehydrogenase from the soluble fraction was readily adsorbed into the membrane fraction in the presence of salt. Spermidine dehydrogenase appeared to be a membrane-bound enzyme localized in the cytoplasmic membranes in a manner that makes a partial release of the enzyme possible during mechanical cell disruption. When spermidine oxidation was done with the resting cells of C.freundii, a stoichiometric formation of two reaction products, 1, 3-diaminopropane and γ-aminobutyraldeyde, was observed without any lag time. These facts indicate that the enzyme is localized on the outer surface of the cytoplasmic membranes or in the periplasmic space of the organism.

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Cinchomeronic acid (CA) at 10-100 mM enlarged the leaf area of radish seedlings, and at 10 mM, it increased stem elongation. CA was found in free form in the plants. The effects of CA analogs on the growth of radish seedlings were investigated. Quinolinic acid and dinicotinic acid increased stem elongation, but at10 mM, isocinchomeronic acid, dipicolinic acid, lutidinic acid, pyridine monocarboxylic acids, and pyrazine monocarboxylate inhibited elongation. Two carboxyl groups, one at the C-3 position of the pyridine ring and the other at the C-2, C-4, or C-5 position, seem to be required for increased growth. Growth was inhibited by pyridine monocarboxylic acids regardless of the position of the carboxyl group, and growth was also inhibitory by pyridine dicarboxylic acids with one carboxyl group at C-2 and the other at a position other than C-3.

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A transposon 5 (Tn5) insertion was introduced into the genome of A.tumefaciens (A-208 strain harboring a nopaline type Ti-plasmid) using a conjugative pJB4JI plasmid containing Tn5. Five thousand transconjugants were assayed for virulence on carrot (Daucus carota L.) disks; 54 isolates were avirulent or very attenuated. The cellular localization (plasmid or chromosome) of the Tn5 insertion in those isolates were identified by Southern hybridization analysis. An avirulent mutant (B-90 strain) with the Tn5 insertion in the chromosome was selected and characterized. The mutant had the same growth rate as that of the parent strain in L-broth. The mutant and the parent strain had similar attachment ability to carrot root cells. Tn5 was inserted into one site of the chromosome. The wild-type target chromosomal region (1281 base pairs) was cloned and sequenced. An open reading frame (ORF) consisting of 395 base pairs was identified. The wild-type DNA fragment (1.6 kb) containing the ORF introduced into B-90 strain complemented the avirulent phenotype of the strain. A soluble protein was predicted from the ORF. The Tn5 was inserted near the 3'-terminal of the ORF. Homology search of this ORF found no significant homology to known genes and proteins. Thus, the ORF identified in this paper seems to be a new chromosomal virulence gene of A.tumefaciens.

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The magnitude, resistance, and reactance of impedance of potato tubers were significantly influenced by irradiation. Although different types of electrode resulted in different values of these impedance parameters, the ratios of the impedance parameters at 5 kHz to 50 kHz got rid of the influence of the type of electrodes. The ratio of impedance magnitude at 5 kHz to 50 kHz (Z_5k/Z_50k) resulted in a larger difference between unirradiated and irradiated potatoes than those of resistance and reactance. The degree of difference in Z_5k/Z_50k between unirradiated and irradiated potatoes was dependent upon the measuring temperature and the region of the tuber punctured with electrodes. The impedance ratio (Z_5k/Z_50k) measured at 22-25°C at an apical region of potato tuber with 1 mA of alternating current resulted in the best identification of irradiated potatoes and enabled differentiation of irradiated potatoes from unirradiated ones for up to 6 months.

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p-Nitrophenyl 6⁵-O-β-D-galactopyraosyl-α-maltopentaoside (L⁶G5P) was synthesized by the sequential use of the transglycosylation and hydrolytic action of β-D-galactosidase from Bacillus circulans. The enzyme produced L⁶G5P (at a yield of 8.0% based on the amount of p-nitrophenyl α-maltopentaoside added) from lactose as the donor and p-nitrophenyl α-maltopentaoside as the acceptor. The frequency at which of human pancreatic α-amylase and salivary α-amylase catalyzed the cleavage of glycosidic linkages in L⁶G5P was calculated by analysis of the digests by high-pressure liquid chromatography. The modes of action of the two isozymes differed. Both hydrolyzed L⁶G5P and produced p-nitrophenyl α-maltoside and p-nitrophenyl α-D-glucopyranoside, but human pancreatic α-amylase produced more of the latter than human salivary α-amylase. Thus, L⁶G5P could be used to assay of the two enzymes differentially in serum.

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The sweet protein monellin consists of two noncovalently associated polypeptide chains, the A chain of 44 amino acid residues and B chain of 50 residues. Synthetic monellin is 4000 times as sweet as sucrose on a weight basis, and the native conformation is essential for the sweet taste. Knowledge of the active site of monellin will provide important information on the mode of interaction between sweeteners and their receptors. If the replacement of a certain amino acid residue in monellin removes the sweet taste, while the native conformation is retained, it may be concluded that the position replaced is the active site. Our previous replacement studies on Asp residues in the A chain did not remove the sweet taste. The B chain contains two Asp residues at positions 7 and 21, which were replaced by Asn. [Asn^B21] Monellin and [Asn^B7] monellin were 7000 and 20 times sweeter than sucrose, respectively. The low potency of the [Asn^B7] monellin indicates that Asp^B7 participates in binding with the receptor. Asp^B7was then replaced by Abu. [Abu^B7] Monellin was devoid of sweetness, and retained the native conformation. Asp^B7 is located at the surface of the molecule (Ogata et al.). These results suggest that Asp⁷ in the B chain is the highly probable active site of monellin.

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A variety of 1, 5-disubstituted imidazoles and related compounds were prepared, and their bleaching activity was evaluated by using the lettuce seedling test. 5-(4-Benzyloxyphenyl)-1-ethylimidazole (13) caused clear chlorosis, while the 2- and 3-benzyloxyphenyl analogs had no activity. In the 5-(4-benzyloxyphenyl) imidazole series, only the 1-propyl analog showed significant activity, as well as compound 13. Both substituents at the 1- and 5-position of the imidazole ring were indispensable for this activity. Of the series of compounds tested, 1-ethyl-5-stilbenylimidazole (22) and 5-[4-(3-chlorobenzyloxy) phenyl]-1-ethylimidazole (33) showed the highest activity. Compound 33 at 30 ppm decreased the chlorophyll content in the lettuce seedlings to less than 20% of that in the control.

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A new polypeptide inhibitor, AI-409, that inhibits human salivary α-amylase, was purified from a fermentation broth of Streptomyces chartreusis strain No.409. This protein consists of a single-chain polypeptide of 78 amino acid residues, and includes two disulfide bridges. The primary structure of AI-409 and the locations of the disulfide bridges were identified by enzymatic digestion and the automatic Edman technique. Enzymatic digestion was done with trypsin, carboxypeptidase Y, and chymotrypsin. One of the disulfide bridges was between Cys (10) and Cys (26), and the other between Cys (44) and Cys (71).

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Two yellow fluorescent compounds, pratenols A (1) and B(2), were isolated from the aerial parts of red clover (Trifolium pratense) infected by the fungus Kabatiella caulivora. The structure of each was established by chemical and spectroscopic methods.

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Single cells were prepared from mesocarp tissue of ripe persimmon (Diospyros kaki cv.Fuyu) fruits, and inter-or intracellular localization of acid invertase (AI, EC 3.2.1.26) was studied. AI was localized in the intercellular fraction (cell wall fraction). AI was isolated and purified from the cell wall fraction of ripe persimmon fruits by column chromatography on SE-53 cellulose and Toyopearl HW 55F. The specific activity of purified AI was 570 units per mg protein at 30°C. The molecular mass of AI was estimated to be 44 kDa by gel filtration over Sephacryl S-200 and 70 kDa by SDS-PAGE. The optimum pH of the activity for sucrose was 4.25. The purified enzyme hydrolyzed sucrose and raffinose but not melibiose. The enzyme had a K_m of 3.2 mM for sucrose and a K_m of 2.6 mM for raffinose. Silver nitrate (5μM), HgCl₂ (2μM), p-chloromercuribenzoate (100 mM), pyridoxamine (10mM), and pyridoxine (2.5 mM) inhibited AI activity by 95, 85, 100, 41, and 30%, respectively.

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Four geometric isomers of 4, 11-hexadecadienal were prepared and their pheromone activities to male eri-silk moths were evaluated by using the fluttering test and electro-antennography. None of these compounds showed any activity in spite of their similar structure to other pheromone mimics and to the natural pheromone. These result suggest that the presence of 6, 11-double bonds is essential for pheromone activity.

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A facultative formate-utilizing bacterium, Paracoccus sp. strain 12-A, with a high specific activity (11.6 units/mg) of NAD⁺-dependent formate dehydrogenase, was isolated from sewage. From a crude extract of the cells, the enzyme was purified to homogeneity by ammonium sulfate fractionation, DEAE-cellulose column chromatography and hydroxyapatite column chromatography. The enzyme protein amounted to 15% of intracellular soluble proteins in strain 12-A. The enzyme had a molecular weight of approximately 100, 000 by gel filtration with Sephadex G-150 and 49, 000 by SDS-polyacrylamide gel electrophoresis, and an isoelectric point of 5.4. The pH and temperature optima ware 6.5-7.5 abd 50-55°C, respectively. The enzyme was stable at pH 6.0-10.0 and up to 50°C. The apparent K_m values for formate and NAD⁺ were calculated to be 5.0 mM and 0.036 mM, respectively.

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To obtain information concerning the effects of ionophores on biological membranes, the thermotropic behavior of ionophores such as gramicidin A' and valinomycin in monolayers was investigated by measuring the surface pressure-area (π-A) and the surface viscosity-area (η_s-A) isotherms. Gramicidin A' had an isotherm having the treasition from a liquid-expanded through an intermediated to a condensed state, while valinomycin had a concave isotherm. The π-A isotherms for two ionophores had a decremental shift with increasing temperatures, depending upon a variety of their molecular structures. A distinict difference between the two ionophores in η_s-A isotherms was observed. In addition, the interaction of dimyristoylpho-sphatidylcholine (DMPC) with the two ionophores in mixed monolayers was investigated. When valinomycin was mixed with DMPC, no deviation from the additivity rule occurred below and above the phase transition temperature T_c of DMPC. However, when gramicidin A' was mixed with DMPC, a considerable negative deviation from ideal mixing occurred below T_c, suggesting the formation of an irregular ripple structure.

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Bacillus thuringiensis δ-endotoxin, CryIA (a), increased ion permeability of brush border membrane vesicles isolated from midgut epithelia of Bombyx mori larvae. This ion permeability change was measured with a potential-sensitive fluorescent dye, 3, 3'-dipropylthiadicarbocyanine iodide. This effect was observed at concentrations of the toxin that correspond to normal effective doses in vivo. CryIA (b) and heat-treat CryIA (a) did not show this effect. CryIA (a) did not show this effect on rat renal brush border membranes. The effects depended on the toxin dose in saturable manner. These suggest that this assay system reflects the mode of action of δ-endotoxin in vivo. The toxin increased various ion permeabilities, suggesting that δ-endotoxin forms non-selective cation pores on brush border membranes.

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Enzymatic production of D-alanine from DL-alaninamide was investigated. A bacterial strain, NJ-26, which was identified as Arthrobacter sp., was isolated from activated sludge as a producer of a D-alaninamide specific amide hydrolase (D-amidase). This strain produced D-amidase in the presence of alaninamide as an inducer. The enzyme was purified about 260-fold to near homogeneity. The enzyme is a monomer polypeptide with a molecular weight of about 67, 000 as estimated by gel filtration column chromatography. The optimal pH for activity was 7.5. It showed a high D-stereospecificity toward alaninamdie. The relative velocity toward L-alaninamide was about 0.7% of that toward D-alaninamide. The K_m for D- and L-alaninamide were 4.2 mM and 26.1 mM, respectively. After optimization of the reaction conditions, 105 g/liter of D-alanine was generated from 210 g/liter DL-alaninamide with over 99% enatiomeric excess as a result of cellular reaction and all of the L-alaninamide remained in the reaction mixture.

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A gene coding for human nerve growth factor (hNGF) was constructed for expression under control of the trp promoter in E.coli. The plasmid pTRSNGF contained a synthetic hNGF gene fused, in frame, to the region encoding the β-lactamase signal peptide. The plasmid pTRLNGF contained the same coding sequence as hNGF attached downstream from the N-terminal fragment of the trp L gene. E.coli cells harboring pTRSNGF produced an amount of hNGF constituting 4% of the total cellular protein, and removed the β-lactamase signal peptide. The mature protein hNGF was biologically active in the PC12h bioassay for neurite outgrowth. This biological activity was comparable to that of authentic mouse NGF. E.coli cells harboring pTRLNGF produced an amount of fusion protein hNGF constituting 25% of the total cellular protein. Although the fusion protein hNGF formed inclusion bodies in cells, dissolved fusion protein hNGF was active in neurite outgrowth from PC12h cells.

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Linolenic acid contents of glycolipids increased in irradiated potatoes during strage, accompanied by a decrease of linoleic acid. The puncturing of a potato tuber with a needle of a microsyringe caused the similar changes; the elevation of linolenic acid level and decline of linoleic acid were observed within 24h after puncturing. Irradiation before the puncturing reduced the degree of the increase of linolenic acid in response to the mechanical injury. The rate of [¹³C] acetate incorporation into lipid fractions of irradiated tubers was smaller than that of unirradiated tubers, and polyunsaturated fatty acids (linoleic and linolenic acids) of lipid fractions were weakly labeled in irradiated tubers as compared with unirradiated ones. The results in this study indicate that irradiation retards lipid metabolism in response to mechanical injury.

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The complete set of groES and groEL gene homologues from Bacillus subtilis Marburg 168 was identified, cloned, and characterized. The nucleotide sequence indicated the presence of two open reading frames corresponding to the groES and groEL genes. The presumptive GroES and GroEL proteins were calculated to be polypeptides of 10, 175 and 57, 175Da, respectively, and showed extensive sequence similarities with the known GroES and GroEL proteins of Escherichia coli and Mycobacterium tuberculosis. A heat-inducibel transcript initiated upstream of the groES coding region was identified by primer-extension analysis of in vivo transcripts, indicating that the two genes consist of an operon. At least six heat-shock inducible proteins were identified in the cell extract of heat treated B.subtilis. Two proteins of 10 and 60 kDa overproduced in B.subtilis cells carrying a multi-copy groES and groEL plasmid were demonstrated to correspond to two out of the six heat-shock inducible proteins. The groES and groEL genes of B.subtilis were physically mapped on the 60° region of a 360°map and genetically mapped at the position of 40% linkage with the purB locus using PBS1 transduction of groEl genes tagged with a chloramphenicol resistance (chl') marker.

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The complete primary structure of a base non-specific and adenylic acid preferential RNase (RNase Le₂) from the fruit bodies of Lentinus edodes was analyzed. The sequence was mostly determined by analysis of the peptides generated by V₈ protease digestion and BrCN cleavage (including α-chymotryptic, and V₈ protease digest of BrCN fragments). It consists of 239 amino acid residues. The molecular weight is 25831. The location of 10 half cystine residues were almost superimposable on those of known fungal RNases of the RNase T₂ family. The sequence homologies between RNase Le₂ and four known fungal RNases of the RNase T₂ family, RNase T₂, RNase M, RNase Trv, and RNase Rh, are 102, 103, 109, and 74, respectively. The homologous sequences are concentrated around the three histidines, which are supposed to form the active site of RNase T₂ family RNases.

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The synthesis of glucooligosaccharides from α-D-glucose-1-phosphate by transglucosylation with sucrose phosphorylase from Leuconostoc mesenteroides was studied using the purified enzyme and high performance liquid chromatography. The enzyme had a rather broad acceptor specificity and transferred glucosyl residues to various acceptors such as sugars and sugar alcohols. Especially. 5-carbon sugar alcohols (pentitols), D- and L-arabitol were acceptors equal to D-fructose, which was known as a good acceptor. The transfer product of xylitol formed by the enzyme was investigated. The structure of the product was found to be 4-O-α-D-glucopyranosyl-xylitol (G-X) by acid hydrolysis and ¹³C-nuclear magnetic resonance analysis. G-X is a probable candidate for a preventive for dental caries because it reduced the synthesis of water-insoluble glucan by Streptococcus mutans and kept a neutral pH in the cell suspension.

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In this study, we investigated the effects of short-chain, middle-chain, and long-chain fatty acids on the activity of rat liver α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase [EC 4.1.1.45] (ACMSD), a key enzyme of tryptophan-niacin metabolism. Moreover, we examined the cholesterol metabolism and lipid peroxidation in relation to ACMSD activity in rats. When diets containing 2%, 5%, and 10% levels of fatty acids were given to rats for a week, saturated fatty acids and elaidic acid (trans form) did not suppress the ACMSD activity in liver. But polyunsaturated fatty acids such as linoleic acid, linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) strongly suppressed the liver ACMSD activity. Five % sorbic acid and oleic acid tended to suppress the liver ACMSD activity weakly. On the other hand, this report indicated that there is no correlation between liver ACMSD activity and cholesterol levels of serum or liver, but there is a weak negative correlation between liver malondialdehyde concentration and liver ACMSD specific activity.

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Blue pigment-producing callus was induced from fruit of Clerodendron trichotomum Thunb. on Linsmaier and Skoog (LS) medium with 10μM 2, 4-dichlorophenoxyacetic acid (2, 4-D). Callus grew on LS medium with either 2, 4-D or 1-naphthaleneacetic acid (NAA) on subculture. Callus growth and blue pigment formation were much improved by selection on LS gellan gum medium with 2μM NAA. Kinetin and benzyladenine (1μM) inhibited blue pigment formation. One of the blue pigments was confirmed to be trichotomine by HPLC, TLC, and NMR spectra; two others were presumed to be trichotomine G₁ and N, N'-di (D-glucopyranosyl) trichotomine on the basis of comparison with the blue pigments from C.trichotomum fruit on HPLC.

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A series of 1, 2-dithiolanes, 1, 2-dithianes and related compounds bearing a nitrogen-containig substituent were synthesized and their pesticidal activity was tested. A new general synthetic route to 1, 2-dithiolanes was established from 1, 3-diols. A variation in the position and character of the nitrogen atom is shown to be allowable to some extent for promoting insecticidal activity, unlike the case of sulfur atoms. Most compounds showed acaricidal activity, the strongest being displayed by cis-3, 5-bis (dimethylaminomethyl)-1, 2-dithiolane.

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L-156, 602, a C5a receptor antagonist, was found as an immunosuppressant with preferential effects on delayed-type hypersensitivity (DTH) in our screening program and it was shown that L-156, 602, supressed the efferent phase of DTH. Here, we tested its efffects on experimental models of inflammation induced in mice. L-156, 602 did not suppress serotonin- and carrageenan- induced inflammation while it completely suppressed concanavalin A-induced inflammation 4 h after elicitation. The inflammation appeared 24 h after the elicitation with concanavalin A and it was significantly suppressed by L-156, 602. Muramyl dipeptide (MDP)-induced acute joint inflammation was also significantly suppressed by L-156, 602. These results demonstrated the unique immunomodulating properties of L-156, 602 in mouse experimental models of inflammation.

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We investigated the combined effects of ethanol and polychlorinated hiphenyls (PCB) on ascorbic acid metabolism, liver drug-metabolizing enzymes, and lipid metabolism in rats fed on a diet containing by 36% by energy of ethanol and 0.005% of PCB, either singly or in combination, for 49 days. Ethanol and PCB given together synergistically affected the amount of ascorbic acid excreted in the urine and the serum concentration of ascorbic acid. This synergistic effect was also observed in the activity of aniline hydroxylase in the liver. Ethanol and PCB given together seem to have had different effects on lipid metabolism. These results suggest that the effect of ethanol on the metabolism of ascorbic acid and of drugs may be enhanced by combined administration with PCB, and that the ascrobic acid deficiency and/or modification of the drug metabolism may become more serious.

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A new method for the microbial transformation of water-insoluble compounds is proposed. Microorganisms were placed on the interface between hydrophilic carriers such as agar and hydrophobic organic solvents. These microorganisms couls catalyze various transformations of synthetic substrates such as hydrolysis, esterification, oxidation, and reduction more efficiently than emulsion systems. This new type of bioreactor was tentatively named on Interface Bioreactor.

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An acid α-glucosidase (AAG) with an optimum pH of 4.5 and two isoforms of neutral α-glucosidase (NAG I and II) with an optimum pH of 6.5 were partially purified from preclimacteric banana pulp tissues by monitoring the 4-methylumbelliferyl α-D-glucoside (4MUαG) hydrolyzing activity. The molecular weights of the AAG and the two NAG were 70, 000 and 42, 000, respectively, by gel filtration. By kinetic studies, the AAG was found to be a typical maltase that required substrates such as maltose, maltotriose, maltotetraose, and maltopentaose rather than soluble starch. On the other hand, the two NAGs preferred 4MUαG to maltose as substrate and their maltase activities were about 50 times lower than that of the AAG. The NAGs, as well as the AAG, did not hydrolyze isomaltose, trehalose, sucrose, or glycogen at all. Sucrose was a competitive inhibitor of the AAG but not NAGs toward 4MUαG. Glucose and maltose were also competitive inhibitors of both AAG and NAGs.

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