Inorganic sulphur sources for the growth of the dermatophyte microsporum gypseum

Suitability of 10 inorganic compounds at a concentration of 1mm as sulphur sources for the growth of the dermatophyteMicrosporum 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.     

Conditioned pathogenicity of microsporum gypseum biochemical mutants

Experimental infections of guinea pigs with three biochemical mutants ofMicrosporum gypseum are described. Under normal conditions the mutants are avirulent. The virulence became manifested in two mutants (1) when substances necessary for growth of individual mutants were brought into the place of inoculation, (2) when the defense mechanism of the organism was altered with the application of immunosuppressive drugs. One of the mutants was permanently avirulent. The importance of experimental results for explanation of conditioned pathogenicity of some dermatophytes is discussed.     

Isolation and identification of the principal siderophore of the dermatophyte Microsporum gypseum

The dermatophyte Microsporum gypseum has been shown to produce two siderophores under conditions of low-iron stress. These compounds have been separated as Fe(III) complexes on silica gel, and the principal siderophore has been identified as ferricrocin using the methods of amino acid analysis, comparative thin-layer chromatography, partial sequencing by gas chromatography-mass spectrometry, ultraviolet spectroscopy, and proton nuclear magnetic resonance spectroscopy of the Al(III) complex.     

Selection of sulphur sources for the growth of Butyribacterium methylotrophicum and Acetobacterium woodii

Sulphide and cysteine inhibited growth of batch cultures of Butyribacterium methylotrophicum at moderate concentrations (above 0.5 mM) during growth on glucose (10 mM). The ability of several sulphur sources to replace sulphide was tested in cultures of B. methylotrophicum or Acetobacterium woodii. With sulphite (1 mM), thiosulphate (0.5 mM), elemental sulphur, and dithionite (1 mM), but not sulphate (1 mM), cultures of both organisms grew and produced some sulphide. With elemental sulphur as the sulphur source, toxic levels of sulphide accumulated. Optimal levels for the cultivation of B. methylotrophicum with sulphite were 0.5–2.0 mM, but at higher concentrations the growth rate decreased rapidly, while with dithionite up to 4.0 mM the growth rate was relatively unaffected. In chemostat cultures of B. methylotrophicum with dithionite (1 mM) as the sulphur source and glucose as the limiting substrate, dilution rates up to 0.40 h^–1 were obtained. Thiosulphate could only be used in batch cultures in combination with the reductant titanium(III)nitriloacetate, but in continuous cultures the addition of the reductant to the reservoir was not necessary, because once growth had started enough sulphide was produced to keep the fermentor reduced. The maximum growth rate of B. methylotrophicum with thiosulphate in batch and continuous culture was 0.26 h^–1. Both thiosulphate and dithionite are more convenient sulphur sources than sulphide, but dithionite is more versatile because of its reductive properties and the faster growth it allows.Offprint requests to: T. A. Hansen     

High-analysis granular sulphur assemblages as sources of sulphur for lucerne

Summary A growth chamber study was conducted to compare five granulated sulphur assemblages and a commercially available prilled sulphur with gypsum and flowers of sulphur as sources of sulphur for lucerne grown on two sulphur deficient soils, one from the Armstrong area of B.C. and one from California. Following one surface application of the various sulphur supplying materials at rates of 37.5 mg, 75 mg and 150 mg of sulphur per 3750 g of soil, four consecutive harvests were removed from the Enderby silt loam during a 145 day period and three cuttings were taken over a 119 day cropping interval on the Willits soil from California.Although gypsum and finely divided sulphur were the most effective sources, three of the five assemblages also had a favourable influence upon yield of lucerne, sulphur concentration and sulphur uptake. The three acceptable assemblages were sulphur-bentonite, sulphur-goulac-ammonium sulphate and sulphur-gypsum-goulac and they produced beneficial effects upon lucerne growth that were often comparable to those obtained with finely divided sulphur.On the basis of this investigation, it appears that certain granular high-analysis sulphur assemblages made from finely divided sulphur and binding agents, such as gypsum, ammonium sulphate, goulac and bentonite have satisfactory agronomic properties. Because these assemblages have suitable agronomic and physical properties they should be ideal for bulk blending with other granular fertilizer materials or for use in direct application to the soil. Wider scale testing of the sulphur-bentonite, sulphur-goulac-ammonium sulphate and sulphur-gypsum-goulac assemblages would seem to be justified.This paper was presented before the 12th Annual Meeting of the Canadian Society of Soil Science, June 28, 1967, Macdonald College, Quebec.     

Formation of sulphate,sulphite and s-sulphocysteine by the fungusMicrosporum 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.     

Sulphate and methionine as sulphur sources for cysteine and cephalosporin C synthesis in Cephalosporium acremonium

Three prototrophic strains of Cephalosporium acremonium with different potentials for cephalosporin C production show pronounced differences in pools of intracellular sulphur amino acids. The superior strain exhibits the largest pool, particularly of cysteine (four times that of the non-producing strain). In fermentations with this strain methionine was found to be a much better sulphur source than sulphate for both cysteine and antibiotic synthesis. In the presence of methionine the utilization of sulphate is strongly depressed.     

Carbon and sulphur utilization during growth of Pseudomonas fluorescens on potassium d-glucose 6-O-sulphate as the sole sulphur source

Pseudomonas fluorescens N.C.I.B. 8248 was adapted to grow on potassium d-glucose 6-O-sulphate as the sole carbon and sulphur source. Adapted bacteria grew optimally at 37 degrees C on 1.6% (w/v) sulphate ester and growth coincided with the disappearance of the ester from the culture medium at a rate of 2.4mg/h per ml. Three sulphated compounds were detected in the culture fluid at the termination of growth. One of these was present in traces only and has not been identified. The second was present in somewhat greater amounts and was identified as the 6-O-sulphate ester of d-gluconate, and the major metabolite was identified as d-glycerate 3-O-sulphate. Sulphur utilization by the organism was not associated with the appearance of a glycosulphatase enzyme in the cells. However, a novel enzyme system (or systems) was present that liberated inorganic (35)SO(4) (2-) ions from dipotassium d-gluconate 6[(35)S]-O-sulphate and from dipotassium dl-glycerate 3[(35)S]-O-sulphate. Activity towards the latter substrate could not be detected when the adapted or parent Pseudomonas strain was cultured on d-glucose and potassium sulphate as respective carbon and sulphur sources. Some properties of the enzyme acting on the glycerate ester are recorded.     

Nutritive value of lupin-seed protein and leaf-protein concentrates supplemented with various sulphur sources

The effect of DL methionine, methionine hydroxyanalogue (MHA) and sodium sulphate on the nutritive value of lupin-seed protein and leaf-protein concentrate (LPC) from lucerne for rats and chicks was evaluated. Methionine and MHA markedly improved the biological value of both lupin- and LPC-proteins, but the effect of sodium sulphate was not significant.The supplement of organic sulphur-compounds improved the performance of chicks fed on lupin-seed meal, but the effect of sodium sulphate was negligible. There was no significant response to any of the organic and inorganic sulphur compounds in chicks fed on LPC diets. These results suggest that some factor other than methionine defiency is limiting the nutritive value of LPC for these animals.     

Organic solid wastes from urban environment as iron sources for sorghum

Sorghum (Sorghum bicolor L. Moench) which is susceptible to Fe deficiency was grown in two different soils in a glasshouse with two different organic urban wastes (sewage sludge and dog manure) to ascertain their ability to supply Fe and other micronutrients to plants. One soil was calcareous with a history of Fe deficiency. Sewage sludge and dog manure at an application rate of 15,000 g/g to this soil effectively supplied Fe to plants. This effect was not present when the ash rather than the organic matter was used. Ferrous sulfate and Fe-EDDHA (Fe[ethylenediamine di-0-hydroxyphenylacetate]) likewise were not effective. Infrared spectra revealed differences in the fulvic acid for the two sources of solid wastes. The results imply that some sources of organic wastes may be useful in prevention or correction of Fe deficiency in calcareous soils.     

Fluorescent method for studying the morphogenesis and viability of dermatophyte cells

The dermatophyte Microsporum canis is commonly isolated from human and animal infection. The morphogenesis of this fungus was studied during its developmental stages through the fluorescent method Fluorescein Diacetate and Ethidium Bromide. To this end, 50 l dermatophyte suspension were transferred onto cellophane wrapping esterilized discs (2.5 cm of diameter) placed over the surface of Sabouraud dextrose agar on Petri dishes and incubated at 25 °C for 30 days. Every 60 minutes during the first 24 hours and every 12 hours for next 29 days, one disc was transferred onto glass slide, covered with equal volumes of freshly prepared fluorescein diacetate (FDA) and ethidium bromide (EB) solution, mounted with a coverslip and incubated in the dark for 30 minutes, at 25 °C. Each preparation was then examined on a fluorescent microscope. M. canis presented well defined growth stages: (1) tumescence of cells; (2) germination; (3) development of hyphae; (4) production of conidia and (5) tumescence and formation of arthroconidiae. Using the fluorescent method, non viable cells showed a light bright red coloration and viable cells presented green fluorescence. The principal morphological changes have occurred between the 3rd until the 18th day of culture. The method is very useful to demonstrate the dermatophyte growth stages as well as the perfect differentiation between viable and non viable cells.This revised version was published online in October 2005 with corrections to the Cover Date.     

Utilization of various carbon sources for the growth of waterborne conidial fungi

Four isolates of waterborne conidial fungi (Tetracheatum elegans, Tetracladium marchalianum, Pestalotiopsis submersus and Flagellospora penicillioides) were investigated for their carbon requirement, using eight different carbon sources (viz. glucose, fructose, sucrose, xylose, starch, cellulose, dextrin and lactose). All fungi tested grew sparsely on the basal medium lacking in carbon, which was the control. However these fungi were found to vary in their ability to use the supplied sources of carbon. Glucose and sucrose were found to be suitable sources of carbon for all four fungal isolates, whereas fructose proved good for T. marchalianum and P. submersus. Starch and xylose also supported growth of T. marchalianum, P. submersus and F. penicillioides. Cellulose, a polysaccharide, was a poor source of carbon for the growth of these isolates. Four g/L of glucose was recorded as the most useful concentration that gives the maximum dry weight of selected fungi (262 mg and 400 mg for T. elegans and P. submersus respectively after 15 d).     

Amino adids as nitrogen sources for the growth of rice callus tissue

Availability of amino acids for the growth of rice callus tissuewas examined by supplying various kinds of amino acids to thetissue separately or in combination. When an amino acid wassupplied alone as the sole source of nitrogen, only the followingfive amino acids were found to favour the growth of callus tissue;arginine, alanine, asparagine, glutamine and proline. In combinationwith other acids, both AHCH and CMAA were very effective instimulating the growth of tissue, but EHCH was inhibitory. Whenmethionine or arginine was excluded from the CMAA medium, callusgrowth on the medium was reduced significantly. The effect producedby omitting methionine suggested that some amino acid interactionwas involved in this instance. (Received February 19, 1970; )     

有机碳源和氮源对三角褐指藻生长的影响

研究了8种有机碳源和4种氮源对三角褐指藻(Phaeodactylum tricornutum)生长的影响.结果表明,三角褐指藻具有兼养生长的能力,碳浓度为5mmol/L和50mmol/L时,葡萄糖、果糖、乙酸钠和甘油对其生长有明显的促进作用,乳酸钠和乙醇抑制藻细胞生长,半乳糖和柠檬酸钠对其生长随有机碳浓度而异.甘油、葡萄糖和乙酸钠的适宜浓度范围分别为5 -800mmol/L、100 -400mmol/L和50 -300mmol/L.培养液中分别加入50mmol/L甘油、400mmol/L葡萄糖和150mmol/L乙酸钠,培养第14天,三角褐指藻的最大生物量分别为对照的1.45倍、1.25倍和1.11倍.甘油兼养生长的最优氮源是尿素,适宜浓度范围为0.88-8.8mmol/L.当尿素浓度为4.4mmol/L时,最高生物量可达1.31g/L.     

Micro-scale sulphur isotope evidence for sulphur cycling in the late Archean shallow ocean

We report in situ secondary ion mass spectrometer sulphur isotope data for sedimentary pyrite from the 2.52 Ga Upper Campbellrand Subgroup, Transvaal, South Africa. The analysed sedimentary rocks represent a transition in depositional environment from very shallow to deeper water, with strong sedimentological, facies distribution and geochemical evidence for the presence of a shallow redox chemocline. Data were obtained directly in thin section in order to preserve petrographic context. They reveal a very large extent of isotopic fractionation both in mass‐independent (MIF) and in mass‐dependent fractionation (MDF) on unprecedentedly small scale. In the shallow‐water microbical carbonates, three types of pyrite were identified. The texturally oldest pyrite is found as small, isotopically little fractionated grains in the microbial mats. Large (several mm) spheroidal pyrite concretions, which postdate the mat pyrite, record strong evidence for an origin by bacterial sulphate reduction. Rare pyrite surrounding late fenestral calcite is inferred to have formed from recycled bacterial pyrite on account of the slope of its correlated MIF and MDF array. This latter type of pyrite was also found in an interbedded black shale and a carbonate laminite. In a deeper water chert, pyrite with very heavy sulphur indicates partial to almost complete sulphate reduction across a chemocline whose existence has been inferred independently. The combined picture from all the studied samples is that of a sulphate availability‐limited environment, in which sulphur was cycled between reservoirs according to changing redox conditions established across the chemocline. Cycling apparently reduced the extent of recorded sulphur isotope fractionation relative to what is expected from projection in the correlated MIF and MDF arrays. This is consistent with regionally relatively high free oxygen concentrations in the shallow water, permitting locally strong MDF. Our new observations add to the growing evidence for a complex, fluctuating evolution of free atmospheric oxygen between c. 2.7 Ga and 2.3 Ga.     

Evaluation of N-acetylchitooligosaccharides as the main carbon sources for the growth of intestinal bacteria

N-Acetylchitooligosaccharides ((GlcNAc)(n)) with different degrees of polymerization (n=1-6) were prepared as the main carbon sources in media for evaluating the growth of nine intestinal bacteria. A chitohydrolysate was prepared by hydrolyzing shrimp-shell chitin using HCl. After purification, the purity of each (GlcNAc)(1-6) was >86%. The growth of intestinal bacteria was carried out in a basal medium (BM) containing 0.2% (w/v) of each sugar or glucose as the main carbon source and was evaluated using maximum cell densities and specific growth rates. Bacteroides fragilis and Clostridium perfringens could respectively utilize GlcNAc and (GlcNAc)(2) more efficiently for growth than glucose. Bifidobacterium adolescentis and Eubacterium limosum could use (GlcNAc)(1-6) slightly as their main carbon source. Escherichia coli, Lactococcus lactis and Proteus vulgaris could utilize glucose more efficiently than (GlcNac)(1-6). GlcNAc was used more readily than (GlcNAc)(2-6) by Staphylococcus aureus, exhibiting almost the same specific growth rates. In BM, Streptococcus faecalis grew well even without adding each of the sugars tested.