scispace - formally typeset
Search or ask a question

Showing papers on "Chitinase published in 1967"


Journal ArticleDOI
TL;DR: No microorganism capable of lysing two fungi, Rhizoctonia solani and Cladosporium sp.
Abstract: Hyphal walls of Aspergillus phoenicis and Sclerotium rolfsii are composed of large amounts of glucose- and N-acetylhexosamine-containing polysaccharides, and the walls are extensively digested by streptomycete culture filtrates or by a mixture of purified chitinase and β-(1 → 3) glucanase preparations with the release of the monomeric units. A. phoenicis conidial walls also contain polymers of glucose and N-acetylhexosamine, but these walls are resistant to digestion by microorganisms or the enzyme combination active on the hyphae. When the melanin-containing spicules were removed from the spore surface, however, the chitinase and glucanase partially digested the underlying structural components. Microorganisms decomposing hyphal walls of S. rolfsii did not attack the melanin-covered sclerotia produced by this fungus. No microorganism capable of lysing two fungi, Rhizoctonia solani and Cladosporium sp., producing hyphae containing abundant melanin was found. The ecological significance of these findings and possible mechanisms for the protective influence associated with melanins are discussed.

202 citations


Journal ArticleDOI
TL;DR: In this paper, cell walls were extracted from the yeast-like and mycelial phases (YP and MP) of Histoplasma capsulatum and from Saccharomyces cerevisiae by mechanical disruption and washing.
Abstract: Cell walls were prepared from the yeastlike and mycelial phases (YP and MP) of Histoplasma capsulatum and from Saccharomyces cerevisiae by 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 of H capsulatum YP 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 capsulatum MP was shown to resemble S cerevisiae by low chitin content and by the presence of a mannose polymer, soluble in ethylenediamine and water H capsulatum MP 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 Images

91 citations


Journal ArticleDOI
TL;DR: Chitinase preparations from cockroach, bean seeds, and the puff-ball possess lysozyme-like activities, demonstrated by measurements of the effects on cell walls of Micrococcus lysodeikticus and the production of soluble materials reacting in the Morgan-Elson test for acetylamino-sugars.

25 citations


Journal ArticleDOI
TL;DR: The presence of chitin in the cell wall of Penicillium patulum is reported, when it was grown under conditions which permitted the production of griseofulvin.
Abstract: It has been suggested (P. W. Brian, Trans. Brit. Mycol. Soc. 43:1, 1960) that the antibiotic griseofulvin affects only those fungi possessing chitin in their cell wall, but there is a growing body of evidence which makes it unlikely that the presence of chitin is the sole prerequisite for the action of the antibiotic. For instance, K. J. Bent and R. H. Moore (Biochemical Studies of Anti-microbial Drugs, Cambridge Univ. Press, London, 1966) reported that the chitin content of whole mycelia of Botrytis allii increased after griseofulvin treatment rather than decreased, and D. E. Eveleigh and S. G. Knight (Bacteriol. Proc., p. 27, 1965) found that the glucosamine-toglucose ratio of the cell wall of Trichophyton mentagrophytes is unchanged by griseofulvin. This communication reports the presence of chitin in the cell wall of Penicillium patulum, when it was grown under conditions which permitted the production of griseofulvin. P. patulum was obtained through the courtesy of R. S. C. Aytoun of Glaxo Research Ltd., Buckinghamshire, England. It was grown in surface culture in a fully synthetic medium (D. A. Applegarth, Arch. Biochem. Biophys. 120:471, 1967). The medium was supplemented by the addition of sodium chloride (0.2 g/liter) to provide the chlorine atoms of the griseofulvin molecule. The mycelial pads were harvested after 7 days, and the contents of one of the flasks was dried and analyzed for griseofulvin according to the method of A. Holbrook, F. Bailey, and G. M. Bailey (J. Pharm. Pharmacol. 15(Suppl.): 270, 1963). The 7-day mycelial growth from each liter of solution contained approximately 8 mg of griseofulvin. Cell walls were prepared from the mycelial pads in the remaining flasks by ballistic disruption of the hyphae with glass beads in a Sorvall Omnimixer (D. A. Applegarth, Arch. Biochem. Biophys. 120:471, 1967). The purified cell walls contained 12.3% glucosamine and a trace of galactosamine (approximately 0.5%). The hexosamines were eluted from Whatman 3MM paper developed with n-butanolacetic acid-water (4:1:5, v/v). Their identity was established by co-chromatography, with authentic standards, in three solvent systems; by ninhydrin oxidation (P. J. Stoffyn and R. W. Jeanloz, Arch. Biochem. Biophys. 52:373, 1954); and by Nacetylation followed by chromatography in three solvent systems. The identity of the glucosamine polymer as chitin was established as follows. Cell walls (10 mg) were extracted with 1 N acetic acid (5 ml) at 100 C for 20 min. The acid extract was removed by centrifugation, and Gram's iodine solution was added to the extract. No color was obtained. This suggested that the walls did not contain chitosan. The residual walls

13 citations


Journal ArticleDOI
TL;DR: It is concluded that chitinase is synthesized in the microsomal fraction, accumulated in the zymogen granules and released into the cytoplasm from which it then passes into the glandular lumen across the cellular membrane.

10 citations