• Mycobiology
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• v.39 no.2
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• pp.118-120
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• 2011

The ability of Ganoderma to produce extracellular enzymes, including ${\beta}$-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. ${\beta}$-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for ${\beta}$-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neojaponicum showed the strongest activity. Moderate ligninase activity was only observed in Ganoderma neo-japonicum. In contrast, pectinase, amylase, protease, and cellulase were not present in Ganoderma. The results show that the degree of activity of the tested enzymes varied depending on the Ganoderma species tested.

• Journal of Microbiology
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• v.37 no.1
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• pp.14-20
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• 1999

Two extracellular proteases, EP I and EP II, from cells of Oligotropha carboxydovorans (formerly Pseudomonas carboxydovorans) DSM 1227 grown in nutrient broth were purified to greater than 95% homogeneity in five steps using azocasein as a substrate. The final specific activities of EPs I and II were 214.9 and 667.4 units per mg of protein. The molecular weights of native EPs I and II were determined to be 23,000. Sodium dodecyl sulfate-gel electrophoresis revealed the two enzymes to be monomers. The enzymes were found to be serine-type proteases. The activity of EP I was stimulated by Ca2+, Mg2+, and Ba2+, but that of EP II was not. The enzymes were completely inhibited by Fe2+, Hg2+, Co2+, Zn2+, and Cd2+. EDTA and EGTA exhibited a strong inhibitory effect on EP I. The optimal pH for the two enzymes was pH 9.0. The optimal temperatures for EP I and II were 60 and 50$^{\circ}C$, respectively. The enzymes were stable under alkaline conditions. The thermal stability of EP I was higher than that of EP II. Cell-free extracts did not inhibit the purified enzymes. The enzymes were active on casein, azocasein, azocoll, and carbon monoxide dehydrogenase, but weakly active with bovine serum albumin.

• Applied Biological Chemistry
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• v.30 no.2
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• pp.169-178
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• 1987

The extracellular and intracellular inulases from Kluyveromyces marxianus were purified and characterized. The maximum production of both inulases was achieved at stationary phase in a pH-controlled medium at pH 5 with yeast nitrogen base as organic nitrogen source. Each enzyme was concentrated by tannic acid precipitation and separated into two fractions by DEAF-cellulose chromatography. Electrophoretic analysis showed that the four fractions had three glycoprotein bards each. Only main glycoprotein band, however, had both inulase and invertase activities. There were no significant differences between two enzymes in the optimum pH and temperature. But the intracellular inulases had higher heat stability and less affinity toward inulin than the extracellular enzymes do. All the purified enzymes were considered to be exo-inulases using hydrolyzate analysis with TLC.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.921-926
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• 2006

The production and location of xylanolytic enzymes in alkaliphilic Bacillus sp. K-1, isolated from the wastewater treatment plant of the pulp and paper industry, was studied. When grown in alkaline xylan medium, the bacteria produced xylanolytic enzymes such as xylanase, $\beta$-xylosidase, arabinofuranosidase, and acetyl esterase. Two types of xylanases (23 and 45 kDa) were found to be extracellular, but another type of xylanase (35 and/or 40 kDa) was detected as pellet-bound that was eluted with 2% triethylamine from the residual xylan of the culture. The xylanases were different in their molecular weight and xylan-binding ability. Arabinofuranosidase and $\beta$-xylosidase were found to be intracellular and extracellular, respectively, and acetyl esterase was found to be extracellular. The extracellular xylanolytic enzymes effectively hydrolyzed insoluble xylan, lignocellulosic materials, and xylans in kraft pulps.

• Mycobiology
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• v.41 no.2
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• pp.67-72
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• 2013

Pathogenic microbes secrete various enzymes with lipolytic activities to facilitate their survival within the host. Lipolytic enzymes include extracellular lipases and phospholipases, and several lines of evidence have suggested that these enzymes contribute to the virulence of pathogenic fungi. Candida albicans and Cryptococcus neoformans are the most commonly isolated human fungal pathogens, and several biochemical and molecular approaches have identified their extracellular lipolytic enzymes. The role of lipases and phospholipases in the virulence of C. albicans has been extensively studied, and these enzymes have been shown to contribute to C. albicans morphological transition, colonization, cytotoxicity, and penetration to the host. While not much is known about the lipases in C. neoformans, the roles of phospholipases in the dissemination of fungal cells in the host and in signaling pathways have been described. Lipolytic enzymes may also influence the survival of the lipophilic cutaneous pathogenic yeast Malassezia species within the host, and an unusually high number of lipase-coding genes may complement the lipid dependency of this fungus. This review briefly describes the current understanding of the lipolytic enzymes in major human fungal pathogens, namely C. albicans, C. neoformans, and Malassezia spp.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.207-211
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• 1998

Melhylovorus sp. strain SS1 grown on methanol was found to show activities of key enzymes of the linear route, $NAD^+$-linked formaldehyde and formate dehydrogenases, and the cyclic route, hexulose-6-phosphate synthase, glucose-6-phosphate isomerase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase, for formaldehyde oxidation. The activities of the cyclic route enzymes were higher than those of the linear route enzymes. The bacterium also exhibited activities of the key enzymes of the ribulose monophosphate and Entner-Doudoroff pathways and transaldolase involved in the formaldehyde assimilation and the enzymes involved in the biosynthesis of extracellular polysaccharide. Cells grown in the presence of 2.3 mM ammonium sulfate were higher in the productivity of extracellular polysaccharide, but lower in the growth yield, than those grown in the presence 7.6 mM ammonium sulfate. The activities of 6-phosphogluconate dehydrogenase, phosphoglucomutase, and UDP-pyrophosphorylase in cells grown under nitrogen-limited condition were higher, but that of 6-phosphogluconate dehydratase/2-keto-3-deoxy-6-phosphogluconate aldolase was lower, than those in cells grown in the presence of sufficient amount of nitrogen source.

• Mycobiology
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• v.43 no.1
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• pp.81-86
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• 2015

To promote the selection of promising monokaryotic strains of button mushroom (Agaricus bisporus) during breeding, 61 progeny strains derived from basidiospores of two different lines of dikaryotic parental strains, ASI1038 and ASI1346, were analyzed by nucleotide sequencing of the intergenic spacer I (IGS I) region in their rDNA and by extracellular enzyme assays. Nineteen different sizes of IGS I, which ranged from 1,301 to 1,348 bp, were present among twenty ASI1346-derived progeny strains, while 15 different sizes of IGS I, which ranged from 700 to 1,347 bp, were present among twenty ASI1038-derived progeny strains. Phylogenetic analysis of the IGS sequences revealed that different clades were present in both the ASI10388- and ASI1346-derived progeny strains. Plating assays of seven kinds of extracellular enzymes (${\beta}$-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease) also revealed apparent variation in the ability to produce extracellular enzymes among the 40 tested progeny strains from both parental A. bisporus strains. Overall, this study demonstrates that characterization of IGS I regions and extracellular enzymes is useful for the assessment of the substrate-degrading ability and heterogenicity of A. bisporus monokaryotic strains.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.946-950
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• 2001

Slow-growing pathogenic mycobacterium species, including Mycobacterium bovis BCG, secrete a large amount of glutamine synthetase into culture media. Extracellular and intracellular glutamine synthetases were purified from M. bovis BCG. While the native molecular weights of both glutamine synthetases were estimated to be 370.2 kDa, those of the subunits were 61.7 kDa, indicating that the native forms were composed of 6 subunits. The enzymes showed a hhigh thermal stability and high degree of sequence similarity with the glutamine synthetase from M. tuberculosis in the N-terminal amino acid sequence. Western blotting analysis indicated that the antibodies prepared against both the extracellular and intracellular enzymes exhibited common antigen determinants.

• Journal of Microbiology and Biotechnology
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• v.5 no.5
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• pp.274-279
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• 1995

Ethyl caproate, one of the major flavor compounds deciding the quality of sake (Japanese wine), is produced during the brewing by the action of alcohol acyltransferase and esterases of sake yeast and koji mold. Extracellular esterases of Aspergillus oryzae required for ethyl caproate synthesis were purified partially. The enzymes had different optimum pH and affinity toward substrates. Substrate preferences and inhibition features showed the three enzymes to be B-type esterases or carboxylesterases (EC 3.1.1.1).

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1407-1429
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• 2007

The Burkholderia genus consists of over 40 Gram-negative, ${\beta}$-proteobacteria species that occupy remarkably diverse ecological niches. This genus contains species pathogenic to human, animals, and plants, as well as species involved in promoting plant growth and biodegradation of pollutants. This is largely explained by the extraordinary versatility of Burkholderia, as reflected by the remarkable diversity of extracellular products released by these bacteria. We exhaustively surveyed the extracellular enzymes, siderophores, toxins, antimicrobials, and other secondary metabolites produced by the members of this very diverse genus. Available information on regulation, especially quorum sensing mechanisms, and secretion is highlighted.