ABSTRACT
Keratinolytic potential of A. keratinophila (DSM 44409T), a newly described Amycolatopsis sp. isolated from cultivated soil in Kuwait, was demonstrated using keratinazure as the sole source of carbon and nitrogen as estimated by gel diffusion assay. Effects of 12 various nutritional supplements on the keratinolytic and azocollytic activities were determined. NH4H2PO4 and KNO3 in the medium supported a significantly higher keratinolytic activity than other supplements. However, azocollytic activities in all the supplemented media and the control were same. Best combination of carbon and nitrogen supplements (galactose and NH4H2PO4 respectively) used to evaluate the dynamics of growth and enzymes (keratinase and protease) activities of the isolate revealed a luxuriant growth with optimal keratinolytic activity occurring during the log phase. Other parameters of the fermentation medium, including pH, biomass accumulation, total protein and free amino acid concentrations were also studied.
Subject(s)
Actinomycetales/enzymology , Keratins/metabolism , Peptide Hydrolases/biosynthesis , Actinomycetales/growth & development , Biomass , Carbon , Culture Media , Endopeptidases/biosynthesis , Endopeptidases/isolation & purification , Nitrogen , Peptide Hydrolases/isolation & purification , Sepharose/metabolismABSTRACT
From several soil samples screened for the occurrence of keratinolytic fungi, soils cultivated with ornamental plants were found to contain strains of the dermatophytic fungus Microsporum gypseum. One soil sample was dominated by this species.
Subject(s)
Microsporum/isolation & purification , Soil Microbiology , Chrysosporium/isolation & purification , KuwaitABSTRACT
Two keratinolytic fungi, Chrysosporium keratinophilum and Malbranchea anamorph of Uncinocarpus reesii, and another three wool-colonizing fungi not previously reported to be keratinolytic, Aspergillus fumigatus, A. Flavus and Scopulariopsis candida, were isolated from soil samples baited with animal wool. These fungi were tested for their ability to utilize wool-lipids as sole source of carbon and energy. The lipid contents of wool of various animals ranged between 2 and 5%. The different lipid extracts were similar in composition; they contained steryl esters, sterols, fatty acids, fatty alcohols and monoacylglycerols. The predominant acyl moiety in wool-lipids of different animals was linolenic acid (18:2). The five fungi tested grew well on an inorganic medium supplemented with total wool-lipids as sole sources of carbon and energy. Individual lipid classes fractionated by preparative thin layer chromatography and suspended into inorganic medium were able to support fungal growth as sole carbon sources. These fungi and another eight wool-colonizing strains, C. tropicum, C. zonatrum, C. anamorph of Arthroderma curryei, Microsporum canis, M. distortum, Trichophyton interdigitale, Emmonsia parva and Myceliophthora vellerae could also utilize standard lipids and fatty acids (cholesterol and palmitic and linoleic acids). Evidence fo the uptake and degradation of cholesterol by C. keratinophilum is presented.
Subject(s)
Fatty Acids/metabolism , Fungi/metabolism , Lipid Metabolism , Soil Microbiology , Wool/microbiology , Animals , Ascomycota/metabolism , Aspergillus flavus/metabolism , Aspergillus fumigatus/metabolism , Camelus , Cattle , Chromatography, Thin Layer , Chrysosporium/metabolism , Goats , Microsporum/metabolism , Mitosporic Fungi/metabolism , Sheep , Trichophyton/metabolismABSTRACT
Soil samples from seventeen animal herds (camels, goats, sheep, cows) were surveyed for the occurrence of keratinophilic fungi. Twenty four species related to eleven genera were recovered on defatted wool baits. Eleven Chrysosporium species were reported in the following order of dominance: C. keratinophilum, C. tropicum, C. indicum, C. queenslandicum, C. pannicola, C. carmichaelii, C. state of Arthroderma curreyi, C. zonatum, C. state of A. cuniculi and Chrysosporium state of Renispora flavissima. The Aphanoascus teleomorph of C. keratinophilum, C. indicum and C. tropicum were frequently reported in soils from cow and sheep folds. Scopulariopsis, Cephaliophora and Sepedonium, although not keratinolytic, were also recorded on wool baits of soils from cow herds which are slightly acidic. The frequency and distribution of these fungi are discussed in relation to animal species and the general ecological conditions of desert soils.
Subject(s)
Animals, Domestic , Fungi/isolation & purification , Housing, Animal , Soil Microbiology , Animals , Camelus , Cattle , Chrysosporium/isolation & purification , Desert Climate , Feces/microbiology , Goats , Hydrogen-Ion Concentration , Kuwait , Sheep , Sodium ChlorideABSTRACT
Forty soil samples from different desert localities in Kuwait were surveyed for keratinophilic and geophilic dermatophytic fungi. Sixteen species classified in 9 genera were recovered on wool baits. Chrysosporium species were the most common fungi: Chr. tropicum (60%), Chr. pannicola (32.5%), Chr. queenslandicum (27.5%), Chr. keratinophilum (25%), Chr. indicum (20%) and the Chrysosporium anamorph of Arthroderma cuniculi. The second dominant genus was Malbranchea (27%) represented by two species; followed by Myceliophthora (10%). A number of cleistothecial keratinophilic species were also reported in restricted areas. Ctenomyces serratus Eidam and its Myceliophthora anamorph were new records to Kuwait. The frequency and distribution of these fungi have been discussed in relation to ecological conditions of desert soils.
Subject(s)
Chrysosporium/isolation & purification , Fungi/isolation & purification , Mitosporic Fungi/isolation & purification , Soil Microbiology , Desert Climate , KuwaitABSTRACT
Aspergillus helicothrix sp. nov. is described. The species is based on a single-spore isolate obtained from the type culture of Aspergillus ellipticus Raper et Fennell. It is characterized by conspicuously echinate conidia and cup-shaped sclerotia with coiled setae.
