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The spore coats of mature macroconidia of Microsporum gypseum contained greater carbohydrate–protein ester, disulfide, acid-soluble phosphate, and acid-insoluble phosphate content than mycelial walls. Phosphate was a major constituent of the spore coat, accounting for 6.8% of the dry weight. Spore coat phosphates were located internally as acid-insoluble phosphate, or externally on the spore surface as acid-soluble phosphate. Upon spore germination, the carbohydrate–protein ester, acid-insoluble phosphate, and acid-soluble phosphate content of the spore coats decreased, resulting in considerable alteration of spore coat internal and external properties. Germination was initiated by early alkaline protease and β-1,3-glucanase action, followed by ethyl-esterase, phosphodiesterase, and chitinase activities. These hydrolases were compartmentalized in lysosomal vesicles, which appeared to be delivered to the germinating spore in a coordinated manner.

The enzymatic properties ofNephthys hombergii lysozyme were compared with those of hen egg-white lysozyme. The observed results allowed to conclude that if similarities between both enzymes could be established (variation of the initial velocity of lysis as a function of the ionic strength, influence of urea and histamine), it was nevertheless possible to differentiate them clearly by their affinity constants forM. luteus cells, by the inhibitory power of N-acetylglucosamine and by their action on chitopentaose, chitotetraose and colloidal chitin.

Before both larval moults in Drosophila melanogaster , the chitin in the cuticle is digested to a significant degree by the moulting fluid. A spurt of chitinase activity appears just before each ecdysis, drops sharply after the first ecdysis, and begins to rise again just about the time that chitin degradation becomes evident. The level of enzyme activity/mg of soluble protein reached just before the second ecdysis is about twice that reached before the first, and this declines gradually after the ecdysis until puparium formation. Chitinase activity is measured with a viscometric assay on a chitosan substrate. The enzyme activity is stable, with no loosely bound cofactor. Data also exist supporting the presence of more than one enzyme fraction in Drosophila with chitinase activity.

The cell wall of the yeast form of Histoplasma farciminosum contains 13.2% β-1,3-glucan, 1.0% galactomannan, and 25.8% chitin, whereas the cell wall of mycelial form has 21.8, 4.5, and 40%, respectively, for the same polymers. Also, the cell wall of the yeast form contains α-1,3-glucan (13.5%) and an unidentified polymer (21.5%). Chitin, one of the structural polymers of both yeast and mycelial cell walls, is identified as thin isolated fibers (4 nm wide) or in thick bundles (50 nm wide) of fibers. β-(1-3)-Glucan is also found as thin isolated fibers indistinguishable from isolated fibers of chitin. Fibers 14 nm wide and resembling α-(1-3)-glucan fibers of other fungi are found in the yeast form. The results reported here do not give support to the proposal for a different taxonomic classification.

1. A glycol-chitin-splitting enzyme without lysozyme (muramidase) activity was found in serum from various animals. Goat, cow, hen, sheep and pig possessed high activity. No activity was found in serum from man, monkey, horse, dog, cat, rabbit, guinea-pig or hamster. 2. Glycol chitin has been used as a substrate in purification and characterization. A viscosimetric assay with the use of this substrate was found to be a convenient method. 3. By means of ammonium sulphate fractionation of goat serum and subsequent gel chromatography a 100-fold purification of the enzyme was obtained. 4. The purified enzyme has its optimal activity around pH 1.65 with glycol chitin as a substrate and, when incubated at 50 °C for 60 min, the optimal stability is in the pH interval 3.5–6.5. The pI determined by isoelectric focusing is 4.85 and the molecular weight assessed by gel chromatography is around 60000. 5. The purified goat serum enzyme degrades colloidal chitin with an optimum at pH 5.5 and is thus defined as a chitinase. Goat anti-human lysozyme serum does not inhibit the purified chitinase. 6. To elucidate the origin of the serum chitinase, the concentration of the enzyme was determined in various organ tissues and body fluids. The highest activity with the exception of serum was found in the wall of the fourth stomach of goat and cow.

Approximately 90% of all photosynthetic CO2 fixation is attributed to algae.1 From planktonic microcells to the massive 30-meter kelps, algal cell wall polymers comprise nearly half of the total nonaqueous biomass; between one tenth to one half of all the solar energy converted into chemical bond energy on our planet is stored in the cell walls of algae.

An inducible lytic enzyme complex from Streptomyces satsumaensis was capable of releasing spherical protoplast-like bodies from the mycelium of Geotrichum candidum. An analysis of this enzyme complex revealed the presence of chitinase, mannanase and laminaranase. Also a combination of chitinase and exolaminaranse from other sources could produce the “protoplasts” under standard conditions.

Walls of Mortierella parvispora, Pullularia pullulans, Absidia repens, Fusarium oxysporum , and of several Penicillium species varied in their susceptibilities to digestion by glucanase and chitinase. Polysaccharides were present in the residues remaining after enzymatic digestion. Acid hydrolysates of the walls contained glucose, glucosamine, and a small amount of galactose. The walls of M. parvispora , which also contained fucose, were the least digested by these two enzymes. Much of the M. parvispora wall material was resistant to decomposition by a heterogeneous soil community, and viable hyphae were not lysed by a glucanase-chitinase mixture. Walls of this fungus were fractionated, and the chemical composition of the fractions was determined. The chitin which was abundant in one of the fractions was apparently largely shielded from chitinase hydrolysis by a glucan. The ecological significance of these findings is discussed.

1. As cultures of the fungus Sclerotinia fructigena autolysed, the filtrates contained increasing quantities of a β-N-acetylglucosaminidase. 2. The enzyme was purified up to 42-fold by a combination of isoelectric focusing and gel filtration. 3. It ran as a single band in cellulose acetate strip electrophoresis and in isoelectric focusing (pI3.76). 4. The enzyme did not readily hydrolyse chitin or a glycopeptide with terminal N-acetylglucosamine residues, but rapidly degraded the N-acetylglucosamine dimer NN′-diacetylchitobiose; the monomer was readily utilized by the fungus as a nitrogen source. The Km value for hydrolysis of p-nitrophenyl β-2-acetamido-2-deoxy-d-glucopyranoside at 37°C was 2.0mm. The Sclerotinia enzyme was generally less susceptible to inhibition by 2-acetamido-2-deoxygluconolactone and other related sugars than the corresponding enzyme from other sources. Inhibition by excess of substrate was observed. 5. The culture filtrate also contained N-acetylgalactosaminidase activity; conflicting evidence was obtained as to whether the same enzyme was responsible for both hexosaminidase activities.

The grex of Dictyostelium and Polysphondylium species of cellular slime mould were treated with a variety of proteolytic enzymes and other disaggregating substances. The most effective enzyme for cell separation was crystalline papain, although this did not attack the slime track or stalk. On consideration of the optimum requirements for this digestion (which are given), it is proposed that the cells are bound in the grex by a complex of polysaccharide bound by peptides rather than proteins.

1. 1. Four digestive carbohydrases, laminarinase, maltase, chitinase and amylase, have been demonstrated in Balanus nubilis (Darwin, 1854). 2. 2. The tissues showing highest enzyme activity were as follows: laminarinase; last half of the midgut: maltase, foregut: amylase, glandulae pancreaticae; and chitinase, foremost part of the midgut.

1. 1. Thirty-seven species of marine invertebrates from different systematic and ecological position were quantitatively tested for cellulase and chininase activity in their digestive systems. 2. 2. Enzymes were tested by several methods. Carboxymethlcellulase (CMC-ase) and carboxymethylchitinase (CMCh-ase) activities were estimated by the decrease in viscosity of these solutions and by the increase of the reducing sugars. Chitinase activity by precipitated chitin (PCh) was tested by the simultaneous measurement of the reducing sugar (RS) and N-acetylglucosamine (NAGA) in an incubation mixture and by chitin (Ch), using the last method only. 3. 3. Ascidia Halocyntia aurantium and Metridium senile fimbriatum were found to possess the highest chitinase activity; mollusca Littorina mandschurica and L. brevicula had the highest cellulase activity.

Serratia marcescens was found to be the most active organism of 100 tested for the production of chitinase. Enterobacter liquefaciens produced nearly as much enzyme. Under optimal conditions high yields of chitinase were obtained in 4–6 days. The S. marcescens enzyme system is extracellular and is composed of an endochitinase, a chitobiase, and a factor (CH1) required for the hydrolysis of "crystalline" chitin. As such, it closely resembles the cellulase system of Trichoderma viride, and differs from those chitinolytic systems which act only on degraded forms of chitin. The absence of other hydrolytic enzymes in the S. marcescens filtrates makes this a useful system for determining the role of chitinase as a lytic agent.

Gill lamellae from the young fruiting bodies of the basidiomycete Coprinus micaceus possess cytoplasmic particles with cytochemically demonstrable acid phosphatase activity; they are presumed to be lysosomes.

Spherules of Coccidioides immitis strain Silveira produced in vitro were treated with chitinase and lysozyme. The walls of merthiolate-killed mature endosporulating spherules were degraded by chitinase (500 μg/ml) and by lysozyme (100 and 500 μg/ml). Thus, as was visible through the light microscope, the spherule wall was reduced in thickness from 1 to 2 μm to less than 0.5 μm. The degradation was evident also by release of N -acetylglucosamine, three times as much N -acetylglucosamine being released by chitinase in 12 h as was released by lysozyme in 3 days. However, the effect of lysozyme on living mature spherules was in marked contrast to the effect of chitinase in that treatment with lysozyme led to marked reduction in viability. Exposure to lysozyme (500 μg/ml) for 48 h permitted survival of only 0 to 0.2% of spherules. Thinning of the walls was observed only in the larger spherules (25-35 μm) treated with lysozyme. By contrast, chitinase (500 μg/ml) led to complete dissolution of the walls of living mature spherules but the viability of the liberated endospores was unaffected during contact with chitinase for 48 h. Living non-endosporulating immature spherules and free endospores were also rendered nonviable by lysozyme but not by chitinase.

The degradation of hyaline and melanized cell walls of Aspergillus nidulans has been analyzed using a crude lytic enzyme complex and highly purified β-1,3-glucanase and chitinase produced by a soil streptomycete. The action of these latter two enzymes in combination produced extensive cell wall dissolution, and β-1, 3-glucanase activity, specifically endohydrolytic activity, was a necessary prelude to chitin accessibility and hydrolysis by chitinase. Pigmented cell walls varied in their sensitivity to lysis according to the extent of their melanization. All enzyme components of the lytic preparation were sensitive to the native fungal melanin, with chitinase being the most susceptible to inhibition. The inhibition of the glucanase and chitinase was a time-dependent reaction of the noncompetitive type. Evidence for an association of melanin with chitin in the cell wall has been presented, and studies of semisynthetic melanin-chitin complexes reported. Melanin-bound chitin was extremely resistant to enzymic degradation. The respective roles of enzyme inhibition and substrate protection by melanin in the context of its antimycolytic properties have been discussed.

1. 1. A chitin synthesis in subcellular particles from crustaceans tissues incorporates C14 from uridine diphosphate acetyl-C14-glucosamine into chitin. 2. 2. C14 acetylglucosamine is released from the product on digestion with a chitinase. 3. 3. The enzyme is most active in the presence of 0·4 M NaCl and with chitodextrins added as primer.

The chemical composition of the cell wall of Helminthosporium sativum is described. The wall contains equal amounts of glucosamine and galactosamine. The galactosamine polysaccharide can be separated from the glucosamine by extraction of the wall with hot alkali. The glucosamine polysaccharide, which is insoluble both in cold concentrated acid and hot alkali is digested by a commercial chitinase preparation. The results suggest that two hexosamine polymers are present in the cell wall of this microorganism.

Cell walls of Histoplasma capsulatum and Blastomyces dermatitidis , obtained by mechanical breakage of yeast- and mycelial-phase cultures, were lipid-extracted and then fractionated with ethylenediamine. Unextracted cell walls, lipid-extracted cell walls, and the three fractions resulting from ethylenediamine treatment were examined for monosaccharide and chitin content. The yeast-phase cell walls of five strains of H. capsulatum fell into two categories, designated chemotypes I and II, one of which, chemotype II, was similar to yeast-phase cell walls derived from three strains of B. dermatitidis. H. capsulatum chemotype I cell walls were characterized by lower content of material soluble in ethylenediamine, higher chitin content, and lower monosaccharide content than H. capsulatum chemotype II or B. dermatitidis cell walls. Approximately 80% of the monosaccharides of chemotype I cell walls was combined in forms susceptible to attack by mild acid hydrolysis, compared with about 50% of the monosaccharides of chemotype II and B. dermatitidis. H. capsulatum and B. dermatitidis yeast-phase cell walls could be distinguished, however, by their susceptibility to attack by a crude enzyme system derived from a Streptomyces sp. incubated with chitin as the only carbon source. Both glucose and acetylglucosamine were released from H. capsulatum cell walls, regardless of chemotype, during enzymatic hydrolysis, whereas only acetylglucosamine was released from B. dermatitidis yeast-phase cell walls. Mycelial-phase cell walls of H. capsulatum and B. dermatitidis were characterized by lower content of material soluble in ethylenediamine, higher proportions of mannose, and lower chitin content than their respective yeast phases. Glucose and acetylglucosamine were both released from all mycelial-phase cell walls, whether H. capsulatum or B. dermatitidis , by the crude enzyme system.

The distribution and localization of structural polymers in the cell wall of Neurospora crassa has been studied by selective removal and light and electron microscope examination. Observations with the light microscope indicated that each polymer by itself can provide structural integrity to the cell wall. Examination by electron microscopy showed that the cell wall consists of an outer layer of thick fibrils, identified chemically as a glucan-peptide-galactosamine complex, and an inner layer made up of ß-1,3 glucan and thin fibrils of chitin.

Cell walls were prepared from the yeastlike and mycelial phases (YP and MP) ofHistoplasma capsulatumand fromSaccharomyces cerevisiaeby mechanical disruption and washing. Lipids were extracted with methanol-ether, chloroform, and acidified methanol:ether; a final extraction was made with ethylenediamine. The lipid contents ofH. capsulatumYP and MP walls were about the same. Qualitative and quantitative analyses were made of the products obtained from treatment of the cell walls, or fractions from them, with weak acid or with enzymatic preparations containing glucanase and chitinase activities. YP walls contained much larger quantities of chitin and smaller quantities of mannose and amino acids than the MP walls.H. capsulatumMP was shown to resembleS. cerevisiaeby low chitin content and by the presence of a mannose polymer, soluble in ethylenediamine and water.H. capsulatumMP chitin appeared to be intimately associated with glucose in the wall, since enzymatic hydrolysis of the residue after mild acid hydrolysis of cell walls or fractions from them resulted in the release of glucose and acetylglucosamine; only acetylglucosamine was released from YP walls with such treatment. By electron microscopic observations, the unextracted MP cell walls were much thinner than the YP, and neither wall appeared laminated.

Isolation of the cell wall of the yeast form of Paracoccidioides brasiliensis was carried out by crushing the fungus with a French press followed by sonic treatment and centrifugation. The main components of the cell wall were glucosamine (34%) and glucose (35%). After treating the cell wall with hot NaOH, the glucosamine polymer was isolated as an insoluble residue and was identified as chitin based on its X-ray diffraction and infrared spectrum patterns. Glucan was isolated by treating the cell wall with chitinase (EC 3.2.1.14). It was soluble in dilute alkali, showed high dextrorotation, [α]D = +253 ° in 1 n NaOH, was insoluble in hot water, weakly positive in periodic acid-Schiff reaction and was not hydrolyzed by amyloglucosidase (EC 3.2.1.3), β-1,3-glucanase (EC 3.2.1.39), cellulase (EC 3.2.1.4), and snail digestive juice (a mixture of several glycosidases). The infrared spectrum of glucan showed α-linkage.

The fluorescent chitinase technique is based on the specific affinity of the enzyme for its substrate and applicable when an enzyme can be coupled with a fluorescent dye. Fluorescent chitinase specifically stained chitinous structures in several fungi and an insect, but failed to stain other polysaccharides in bacterial and algal cell walls. Freezing-microtome sections of Drosophila and fungal mycelia 6 μ thick were fixed in acetone for 5 min, then stained and mounted in fluorescent chitinase. Staining of smears of unsectioned fungal material required 5 min in absolute acetone, 5 min in 95% ethanol-1 N aqueous acetic acid (1:1), 10 min in 0.2 M phosphate buffer, PH 5.7, 1 sec in enzyme-dye conjugate, and 10 min in carbonate-bicarbonate buffer (0.2 M, pH 10.7, for chitinase-FITC; pH 7.6, for chitinase-LRBC). Preparations are viewed microscopically with ultraviolet light.

Surmmary Protoplasts of Candida utilis obtained by treatment with helicase built a new wall in a liquid medium. The spherical protoplast was converted to a tubular form which later changed to an ellipsoidal yeast. Walls isolated at different stages of regeneration were analysed. Glucan (42 to 48%), mannan (25 to 31%) and protein (8 to 9%) were the main constituents of walls of normal and completely regenerated ellipsoidal forms. Walls of the tubular forms differed markedly by having a high content of chitin (12 to 18%) and of protein (20%); mannose was present only as traces. The glucan content was similar in normal, tubular and ellipsoidal regenerating yeasts. These results demonstrate that some modifications occur in the structural poly-saccharides of the yeast wall which can be correlated with morphological changes in the reversion process. The significance of glucose, mannose and acetylglucosamine polymers is discussed in relation to the biosynthesis of regenerated walls.

Chemical and ultrastructural studies of the cell walls of the yeastlike (Y) and mycelial (M) forms ofHistoplasma capsulatum G-184B revealed that the Y form contained about 46.5% ofα-glucan, 31.0% ofβ-glucan, 7.7% of galactomannan and 11.5% of chitin, whereas the M form cell wall contained about 18.8% ofβ-glucan, 24.7% of galactomannan, 25.8% of chitin, and essentially noα-glucan. Theα-glucan of the Y form contained mainly anα-(1 → 3)-linkage. Theβ-glucans of both forms may have mainly aβ-(1 → 3)-linkage. Chitin microfibrils were located mainly in the inner portion of the cell walls of the Y and M forms, whereas theα-glucan fibers were observed only in the outer portion of the Y form cell wall.

Development of mature endosporulating spherules from an endospore inoculum was markedly inhibited by human or hen egg-white (HEW) lysozyme at 5 μg/ml. Mature spherules formed in medium containing 5 μg per lysozyme per ml (3.3 × 10 −7 M) were approximately 50% smaller than control spherules. In addition, lysozyme induced a large portion of the endospore inoculum to revert to the mycelial growth phase. Increasing lysozyme concentrations to 10 or 20 μg/ml prompted a nearly complete reversion of the inoculum to the mycelial phase. Mature endosporulating spherules removed from growth medium and resuspended in a solution of human or HEW lysozyme at 18 μg/ml in distilled water prompted leakage of four to five times as much of materials absorbing maximally at 260 nm into the supernatant as untreated control spherules during 90 min of incubation. This four- to fivefold increase in nucleotide loss was evident at 4, 25, and 37 C. The permeability of 1-day-old immature spherules and 8-day-old endospores was considerably altered by lysozyme treatment of cells suspended in distilled water. Large amounts of potassium and nucleotides were rapidly lost by each type of cell when treated with 20 μg of lysozyme per ml. After 270 min of exposure to lysozyme, 98% of the immature spherules and 25% of the endospores were nonviable. Lysozyme adsorption by formalin-killed spherules in the presence of varying concentrations of calcium ion and the rapid alteration of permeability seen after lysozyme treatment suggested that the cell membrane was damaged as a result of binding lysozyme.

Isotherms for adsorption of chitinase on chitin and lysozyme on chitin have been determined at two temperatures and rates of hydrolysis of chitin catalysed by these enzymes have been measured at three temperatures and at several enzyme concentrations for each. Ribonuclease, not an enzyme for chitin, and heat-denatured lysozyme and chitinase show reduced or no adsorption to this substrate. Initial hydrolysis rates of chitin by both enzymes are proportional to total enzyme concentrations in the range of concentrations studied. These kinetics cannot, however, be related to the adsorption isotherms because of the non-equilibrium nature of the isotherms.

Cell walls isolated from the yeast forms of 2 strains each of Histoplasma capsulatum and Blastomyces dermatitidis were treated for up to 3 weeks with an enzyme complex containing chitinase and β-1:3-glucanase. The release of glucose, protein, and amino-sugars from the cell walls was monitored. Cell walls of H. capsulatum lost about 25% of their dry weight as glucose, about 19% as amino-sugar (mainly free N-acetyl glucosamine), and about 6% as protein. Cell walls of B. dermatitidis lost only about 1% of their dry weight as glucose, about 22% as amino-sugar (mainly chitobiose), and about 6% as protein. Electron microscopy of intact yeast-form cells showed them to be extensively degraded by the enzyme complex. Complement fixation (CF) tests indicated that the enzyme treatments caused no substantial change in the antigenic specificity or sensitivity of the cell walls. However, concentrated culture filtrates of B. dermatitidis and the soluble fraction of H. capsulatum cell walls after chitinase treatment, show...

An enzyme that has both β-1,4-glucanase and chitosanase activities is characterized. Evidence for homogeneity was obtained from electrophoresis and sedimentation velocity studies; only one N-terminal amino acid, valine, was found. Results of denaturation studies showed that β-1,4-glucanase and chitosanase activities decreased at equal rates. With carboxymethylcellulose as the substrate, a K m of 1.68 g of carboxymethylcellulose per liter of solution and a V max of 2.20 × 10 −9 mol/min were found. With chitosan (the β-1,4-polymer of glucosamine) as the substrate, a K m of 0.30 g of chitosan per liter of solution and a V max of 0.75 × 10 −9 mol/min were found. A pH optimum of 5.0 was found for β-1,4-glucanase activity, and pH optima of 5.0 and 6.8 were found for chitosanase activity. β-1,4-Glucanase activity had a temperature optimum of 38 C, and chitosanase activity had a temperature optimum of 70 C. Chitosan stabilized both enzyme activities at 70 C. Cellotriose was the smallest polymer capable of hydrolysis. Glucosamine was released by action of the enzyme upon cell wall preparations of several fungi.

THE enzyme contained in a culture fluid of Bacillus circulans has been shown to exert lytic activity towards Aspergillus oryzae and that a polymer of melibiose was liberated from the cell wall. However, the cell wall was not completely lysed by the enzyme owing to the large amount of chitin present. During the search for enzymes causing lysis of fungal cells, it was found that a mixed preparation of chitinase and lytic enzyme exerted strong lytic activity on the cell wall of A. oryzae.

A streptomycete enzyme system active in lysing Aspergillus oryzae and Fusarium solani hyphal walls contained chitinase and several β-(1 → 3) glucanase components. The extracellular β-(1 → 3) glucanase and chitinase were shown to be instrumental in the process of dissolution of hyphal walls. The β-(1 → 3) glucanase and chitinase components alone did not effect solubilization of the hyphal walls, but they were active when used in combination. The major hyphal wall components were chitin and a glucan with β-(1 → 3) linkages. No cellulose was found. The presence of a wall core containing chitin but no glucan was demonstrated by incomplete enzymic hydrolysis. Digestion of F. solani walls yielded 14% glucose, 47% N-acetylhexosamine, and 6% of an insoluble residue which contained mannose, galactose, and a uronic acid.

Evidence is presented that the resistance of Aspergillus nidulans hyphae to lysis by a β-(1→3) glucanase-chitinase mixture results from the presence of melanin in the fungal walls. The resistance of the walls to digestion was directly correlated with the melanin content of the mycelium. A melanin-less mutant of A. nidulans was highly susceptible to hydrolysis by the enzyme mixture. Preincubation of a synthetic melanin with the glucanase, chitinase, and a protease, before addition of the substrate, resulted in a marked inhibition of the rate of substrate hydrolysis. Melanin also appeared to combine with and protect at least certain substrates from decomposition, as indicated by the direct relationship between the extent of inhibition of casein hydrolysis by a bacterial protease and the length of time the protein was incubated with the melanin prior to addition of the enzyme. Melanin was found to be highly resistant to microbial degradation, a likely requirement for the polyaromatic to be effective in protecting fungal structures from lysis or decomposition by natural communities of microorganisms.

Decomposition of chitin by Cytophaga johnsonii was investigated. Unlike other chitinolytic bacteria, some strains of C. johnsonii did not liberate chitinase extracellularly; instead the cells of such strains had need for close contact with the chitin particles in order to hydrolyze them. The cell-free extract of one of these strains, viz., C. johnsonii C35 did show presence of chitinase. The remaining strains liberated an extracellular chitinase and a chitobiase. The partially purified chitinase from the culture filtrates of C. johnsonii C31 was most active at pH 6.3–6.5 and at 40°C. Metabolism of N-acetylglucosamine, a product of chitin hydrolysis, by C. johnsonii C35 and C31 was investigated. The nature of some of the products formed and the steps involved in their transformations by the resting cells and the cell-free extracts suggested that N-acetylglucosamine first gets deacetylated to glucosamine before it is further oxidized to glucosaminic acid by these strains. Both strains were also able to dehydrogenate gluconate to 2-ketogluconate, the former being in all probability the product of deamination of glucosaminic acid.