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J Kunert

Publications and source records attributed to J Kunert.

At least 55 records · Page 3Linked to original sources
PubMed1981

Inorganic sulphur sources for the growth of the dermatophyte Microsporum gypseum.

Suitability of 10 inorganic compounds at a concentration of 1 mM as sulphur sources for the growth of the dermatophyte Microsporum gypseum was investigated. Dry mass of the mycelium after a 11-d growth served as indicator. Sodium sulphate, sulphite and also disulphite, peroxodisulphate and dithionite were the best sources. Growth in the presence of sodium thiosulphate and tetrathionate was slightly worse. Sulphide inhibited the growth, which began only after a longer adaptation. Sodium thiocyanate and amidosulphate were not utilizable as sulphur sources.

Microsporum↗
PubMed1981

Organic sulphur sources for the growth of the dermatophyte Microsporum gypseum.

The suitability of 30 organic compounds (of them 19 sulphur-containing amino acids) at a concentration of 1 mM as sulphur sources for the growth of the dermatophyte Microsporum gypseum was investigated. The dry mass of the mycelium after an 11-d growth served as a measure of utilizability. Of sulphur amino acid cystine, cysteine, reduced and oxidized glutathione, cysteic and cysteinesulphinic acids, S-sulphocysteine, lanthionine, taurine and serine sulphate were the best sources. Methionine and methionine-sulphone were utilized slightly less effectively. Other compounds were medium to poor sources and only S-carboxymethylcysteine was not utilized at all. All organic compounds that are not of amino acid type were poor sulphate sources or were utilized at all. Sodium dodecyl sulphate inhibited germination and growth completely.

Amino Acids, Sulfur↗
PubMed1976

Keratin decomposition by dermatophytes. II. Presence of s-sulfocysteine and cysteic acid in soluble decomposition products.

The dermatophyte Microsporum gypseum was grown on human hair in a mineral medium. Filtrates of cultures of various age were chromatographed on Sephadex gels and further characterized by chemical analysis and thin-layer chromatography. The products of keratin decomposition were separated into two fractions. The first fraction formed 10 to 20% of the bulk and contained proteins low in sulfur content. The second, very wide fraction contained oligopeptides and polypeptides with molecular weights from several hundreds up to approximately 13,000 with a peak at 1,000-2,000 daltons. This fraction contained a relatively high amount of cystine, S-sulfocysteine, and cysteic acid. S-sulfocysteine was present in the free state and also combined in peptides where its amount exceeded that of cystine. This supports the author's hypothesis on keratin decomposition by dermatophytes. According to this hypothesis, the fungus excretes sulfite which cleaves the disulfide bonds of keratin to cysteine and S-sulfocysteine. The substrate, denatured by sulfitolysis, is then more easily digestible by fungal proteases. Besides S-sulfocysteine, comparable amounts of cysteic acid were found in all analyses. This compound most probably originated by air oxidation of sulfur amino acids in the alkaline cultivation fluid.

Biodegradation, Environmental↗
PubMed1975

Formation of sulphate, sulphite and S-sulphocysteine by the fungus Microsporum gypseum during growth on cystine.

The dermatophyte Microsporum gypseum was cultivated in media containing 0.5% cystine in suspension, and 0.05% peptone or 1% glucose and 0.05% peptone. During growth on cystine the excess sulphur was oxidized and excreted into the medium not only in the form of sulphate but also in the form of sulphite. Sulphite was produced especially during first phases of growth, where its quantity was higher than that of sulphate and its maximum concentration exceeded 1 mg/ml. S-sulphocysteine, detected chromatographically and determined quantitatively, originated in large quantities by the reaction of sulphite with cystine in the medium. Both sulphite and S-sulphocysteine were further oxidized to sulphate. After exhaustion of cystine 90-93% of the sulphur present was converted to sulphate in the cultivation medium.

Cysteine↗