Search

The oxidation of decane by a cell-free particulate preparation from Candida intermedia was studied. Decane is oxidized to decanoate via decanol and decanaldehyde. Oxidation of decane to decanol requires molecular oxygen. Decanol is oxidized to decanaldehyde by a nicotinamide adenine dinucleotide-linked dehydrogenase differing greatly in specificity from ordinary yeast alcohol dehydrogenase. Decanaldehyde is oxidized to decanoate by a nicotinamide adenine dinucleotide-linked dehydrogenase that oxidizes long-chain aldehydes but not short-chain aldehydes. The enzymes that oxidize decane, decanol, and decanaldehyde are all induced when decane is present in the medium. These enzymes are apparently located in the cell membrane.

A variety of analytical techniques was employed to study the composition of the chlamydospore of Candida albicans . The outer, thin, electron-transparent layer was found to be composed of glucan, together with a small amount of chitin. The inner, thick, electron-dense layer is proteinaceous. The central structure is composed largely of ribonucleic acid and lipid globules. In addition to being acid-fast, the chlamydospore was found to contain glycolipids and to lose the property of acid-fastness on extraction with ethanol-ether.

Genital yeast infection was studied in 533 women seen in a department of venereology. Yeasts were recovered in culture from 138 patients (26% of the total). Candida albicans accounted for 112 (81%) of the isolates and Torulopsis glabrata for 22 (16%); other yeasts were uncommon. There was no evidence that the presence of yeasts was related to age. 32% of the women who were taking an oral contraceptive harboured yeasts, compared with 18% of those who were not. The symptoms and signs of the women with yeast infections were compared with those with vaginal trichomoniasis and those with no evidence of genital infection. It seems that a clinical diagnosis of vaginal mycosis cannot be made with accuracy and that positive identification of yeasts is necessary; for this, cultural methods are the most satisfactory.

Skin scrapings, mouth swabs, and faecal specimens from children with eruptions in the napkin area and from a series of normal infants were examined for the presence of Candida albicans.This was found in 41% of all napkin eruptions but in only one of the 68 normal infants. While C. albicans is a common secondary invader of all types of napkin eruption, primary Candida infection of the skin in the napkin area is probably uncommon.No evidence was found that generalized psoriasiform or eczematous eruptions occurring in association with napkin rashes are due to an allergic response to the fungus. C. albicans is more likely to be present in a napkin rash if the organism has been found in the alimentary tract.

In a defined medium with added ethionine plus low methionine, phenylalanine, tryptophan, tyrosine, adenine, and additional methionine reversed inhibition of the enteric yeast Candida slooffii by ethionine. Isoleucine and 7-methylguanine restored half-maximal growth. Choline but not triethylcholine inhibited C. slooffii . 6-Mercaptopurine reversed ethionine inhibition and also synergistic inhibition by ethionine plus choline. Protection against ethionine by adenine plus aromatics was also evident with log-phase cells in the absence of methionine. Incorporation of ethionine- ethyl-1 - 14 C by resting cells was partially inhibited by aromatic amino acids and methionine. Ethionine depressed incorporation of 3 H-phenylalanine but not of 3 H-adenine. Ethionine-resistant mutants were isolated which incorporated ethionine efficiently and degraded it to yet unidentified substances not including 5′-ethylthioadenosine. Ethionine-sensitive cells accumulated more S -adenosylethionine (SAE) than resistant mutants. Adenine was a good precursor of SAE. Radioactivity from ethionine- ethyl-1 - 14 C was recovered from cell fractions of ethionine-sensitive cells with the following distribution: cold trichloroacetic acid-soluble > hot trichloroacetic acid-insoluble > lipids > deoxyribonucleic acid > ribonucleic acid. Total radioactivity recovered from ethionine-sensitive cells was twice as much as that from ethionine-resistant mutants.

Controlled acetolysis of yeast mannans yields mixtures of oligosaccharides with (1→2) and (1→3) linkages between the mannose units, whereas the less stable (1→6) linkages of the polysaccharide backbone are cleaved. The “fingerprints,” obtained by gel filtration of the oligosaccharide mixtures, can be used to distinguish between the different yeast mannans. The general method may be useful for determining the taxonomy of yeasts and for making correlations between immunochemical reactivity and mannan structure.

Children with kwashiorkor showed a high incidence of deranged cellular immunity as evidenced by impairment of delayed cutaneous hypersensitivity reactions to candida and diphtheria toxoid antigens and of lymphocyte transformation after phytohaemagglutinin stimulation. This may contribute to their susceptibility to infection. A correlation was shown between the degree of impairment of tests of cellular immunity and the severity of the kwashiorkor. Once recovery was initiated the skin tests gave the expected positive results and the lymphocyte transformation index improved. Protein deprivation may result in impaired deoxyribonucleic acid (DNA) synthesis and in atrophy of both the thymus and the lymphoid tissue.

SELENIUM, long considered an element toxic to the majority of living organisms, may be of physiological importance in various animals as an indispensable part of the diet1–5. It may replace the sulphur atom in sulphur amino-acids6–14 in the proteins of plants, animals and micro-organisms15–18, and could stimulate cell division in a filamentous mutant of Candida albicans19. This stimulation has been related to the replacement of sulphydryl groups in the composition of the cell wall with —SeH groups, the greater stability of which can overcome in the filamentous mutant the deficiency in proteiin-disulphuro-reductase20, an enzyme indispensable to plastification of the cell wall21.

Experiments carried out with crystalline transaldolase from Candida utilis suggest that histidine residues play a specific role in initiating the cleavage reaction. The dihydroxyacetone complex, formed from fructose 6-phosphate and enzyme in the presence of tritium-labeled water, was found to contain tritium, approaching one equivalent per mole of enzyme. This tritium exchanged very slowly with water. It was quantitatively recovered in the C-3 position of β-glyceryllysine when the complex was reduced with sodium borohydride. It was also recovered in the C-3 position of dihydroxyacetone when this was released by heating the complex to 75 °. 3 On the other hand, in the complex itself, the proton appeared to be associated with an essential histidine residue. The following evidence for such a functional histidine residue was obtained: (1) Loss of enzyme activity during photooxidation in the presence of rose Bengal was correlated with the loss of one of the two histidine residues in the protein. (2) In contrast to the free enzyme, the Schiff base intermediate was not sensitive to photooxidation at pH 7.9, indicating that in the complex the histidine residue is protonated. It is proposed that the essential histidine residue acts as a base catalyst which accepts the proton from the C-4 hydroxyl group during the dealdolization reaction.

A heptapeptide has been isolated from the active site of Candida utilis transaldolase after chymotryptic digestion. The amino acid sequence of this peptide has been established as: Ile-Lys-Ile-Ala-Ser-Thr-Tyr. The lysine residue is that involved in Schiff base formation with the substrate.

A use-dilution procedure and screening method are proposed to aid the hospital bacteriologist in selecting the most effective disinfectants. Sixteen disinfectants were tested with and without organic material on six different organisms. Sporadic results usually obtained with quaternaries tested by the procedure of the Association of Official Agricultural Chemists (AOAC) were eliminated by the methods of this study. The use-dilution procedure employs the material upon which the disinfectant is to be used, rather than stainless steel, as in the AOAC use-dilution test. The importance of testing each disinfectant against several organisms and in the presence of organic material is discussed.

When 2,3- or 3,4-dihydroxybenzoic acid, 3,4-dihydroxyphenylalanine, and 3,4-dihydroxycinnamic acid are added to growth media, they are converted to a characteristic brown pigment by Cryptococcus neoformans. This pigment formation has hitherto been encountered only when this microorganism was cultivated on media containing Guizotia abyssinica seed. This phenomenon can be used for differentiating Cryptococcus neoformans from Candida albicans. Possible precursors of these o -diphenols (quinic acid, aromatic monohydroxy acids, or tyrosine) do not give rise to the brown pigmentation.

There are six Candida species commonly isolated from humans: C. albicans, C. tropicalis, C. pseudotropicalis, C. krusei, C. parakrusei, and C. guilliermondi. Some authors recognize a seventh one: C. stellatoidea (Martin et al, 1937; Conant, 1940; Jones and Peck, 1940; MacKinnon and Artagaveytia, 1945; Nickerson, 1953; Conant et al, 1954; Thjotta and Torheim, 1955). Morphology, biochemical reactions, serology, and pathogenicity tests are used to separate the species. References may be found in the classic papers by Benham (1931), Martin et al (1937), Langeron and Guerra (1938), and Skinner (1947). Some authors rely chiefly on morphological characteristics for identification (DeLamater, 1954; Bakerspigel, 1954a and b), while others have stressed biochemical reactions (Drouhet and Couteau, 1954a and b; Thjotta and Torheim, 1955). Methods for the rapid recognition of C. albicans have served as the theme for numerous other papers (Gordon et al, 1952; Weld, 1952; Nickerson and Mankowski, 1953; Haley et al, 1955; Liu and Newton, 1955; Shapiro et al, 1956). The literature is replete with methods for testing the fermentation reactions of Candida species. Since the methods vary it is not surprising that results are often at variance, too. The need, therefore, still exists for a simple, rapid, and reproducible method for testing the fermentation reactions of Candida species; i.e., the production of carbon di

This paper deals with the role of the unsaturated iron-binding capacity of serum in its growth inhibitory action on Candida albicans. The fungistatic power of normal human serum has been described and studied by many investigators (1, 2, 3, 4, 5). Roth and coworkers showed that 10% to 20% of serum added to nutrient medium was sufficient to inhibit growth of Candida albicans. This inhibition could not be overcome by addition of various carbon and nitrogen sources (6, 7).

of reducing substances formed by the cells during glucose metabolism.1*2 We have previously reported the presence in baker's yeast and in Candida albicans of systems utilizing reduced coenzyme II as hydrogen donor for the reduction of oxidized glutathione by glutathione reductase,3,4 and transferring hydrogen from reduced coenzyme I to cystine in the presence of its reductase.5 This paper describes sulfite reduction by yeasts with special reference to the pronounced abilities of some species of Candida to reduce inorganic sulfite when it is supplied as a bismuth complex in appropriate mediums. Certain species of

With the help of an automatic protein sequenator, we have verified a prediction made by us in a recent paper, namely that residue 16 in Candida krusei cytochrome c is a glutamine and not a glutamic acid. Neurospora crassa cytochrome c now remains the only mitochondrial cytochrome c which apparently does not have a glutamine at this position. In the course of this investigation, from two strains of Candida krusei we isolated two cytochromes which differ in amino acid composition. One of them seems to correspond to that described in the literature. Two of the differences have been located.

It is now known that Candida albicans as a distinct species can be classified into groups A and B by means of a direct agglutination test with absorbed rabbit antisera (Hasenclever & Mitchell, 1961a). Although these workers attempted to employ double diffusion in agar-gel as an alternative method, the results were reported as being not consistent in showing the differences observed with agglutination tests. Nevertheless, double diffusion has demonstrated that two serological groups do in fact exist and that the so-called group A and group B strains as supplied by Dr Hasenclever can be differentiated by this means (Stallybrass, 1964). An attempt was made by Hasenclever & Mitchell (1963) to correlate the C. albicans groups with the site of isolation in 242 patients, although unfortunately many of the sites were listed together and no figures are available for particular sources such as sputum. In one collection of 55 vaginal cultures from an unspecified number of pregnant Negro women 22 belonged to group A and 33 to group B, whereas in another collection of 653 cultures obtained from 242 patients 68 % were A and 32 % B. As the particular strains of C. albicans isolated from the several sources in individual patients may sometimes have been identical, the figures indicate neither the true incidence of group A and group B strains at the site of isolation, nor the total incidence in the 297 patients. The present paper reports the results of grouping 234 strains of C. albicans obtained from 234 patients in southern England during 1962 and 1963, using the agar-gel double diffusion technique.

ZEYA, H.I.(University ofNorthCarolina, Chapel Hill), ANDJ.K.SPITZNAGEL. Cationic proteins ofpolymorphonuclear leukocyte lysosomes. II.Composition, properties, andmechanism ofantibacterial action. J.Bacteriol. 91:755-762. 1966.A basic proteins fraction fromguinea pigpolymorphonuclear (PMN)granules was obtained byacidextraction andprecipitation with20%(v/v) ethyl alcohol. The fraction accounted formostoftheantibacterial activity ofthePMN granules and corresponded totheantibacterial cationic components ofintact granules (bands I, II,andIII) resolved byzoneelectrophoresis. Absence fromthefraction ofcomponents identical totheenzymatic components ofintact lysosomes showed that the fraction wasessentially free fromlysosomal enzymes. Theaminoacidanalysis of proteins inthefraction gaveapreponderance ofbasic aminoacids (25%),especially ofarginine (16%). Thecomparative aminoacid analysis showed that thelysosomal cationic proteins (LCP)fraction wasmarkedly different fromnuclear histones. The LCPfraction manifested antibacterial activity against certain gram-negative and gram-positive microorganisms, including Candida albicans, andexhibited stoichiometric relationship inits activity. Microorganisms treated withLCPfraction were agglutinated. Anionic substances suchasnucleic acids, heparin, andendotoxin effectively blocked theantibacterial activity ofthefraction. TheLCPfraction caused suppression ofoxygen uptake bybacterial cells anddamaged thepermeability barriers ofcells asmanifested byrapid release ofP32aswell asultraviolet-absorbing material at260m,u, inthesupernatant fluid. Thepreceding paper dealt withtheelectrophoretic resolution oftheantibacterial activity of polymorphonuclear (PMN)lysosomes, distinct fromknownlysosomal enzymes. Theactivity was associated withcationic protein components which migrated fastest towards thecathode ahead oflysozyme andother enzymes. Thispaper describes someofthebiological and biochemical properties ofthelysosomal cationic proteins inrelation tothemechanism oftheir antibacterial activity.

This paper describes the comparison of the Sterifil lysis-filtration (SLF) blood culture procedure with a standard Trypticase soy broth (TSB) technique. The lysing solutions employed in the SLF system, Triton X-100 (alkyl phenoxy polyethoxy ethanol) and sodium carbonate, were deleterious to most bacteria commonly encountered in bacteremia except staphylococci and enterococci. Candida was not adversely affected. There was a positive correlation between the tolerance of the microbial isolants to the lysing solutions and their recovery by the SLF technique. A total of 3,554 cultures were run in parallel and 398 isolants were obtained. Of 201 gram-positive isolants, 135 were recovered by both techniques, 43 were detected by the TSB technique only, and 23 were recovered only with the SLF method. In sharp contrast, of 168 gram-negative isolants, 28 were recovered in common, 130 were isolated only by TSB, and 10 were recovered only with the SLF method. The SLF method detected all cases of candidemia detected by the TSB method plus an additional 12 for a total of 29 cases. The SLF method, as currently described, is generally too toxic to bacteria for routine use in a clinical laboratory.

A new crystalline antifungal compound, myriocin, has been isolated from culture filtrates and mycelium of the thermophilic ascomycete Myriococcum albomyces. Myriocin is strongly active in vitro against yeasts and dermatophytes. This paper deals with the production, isolation, and purification, as well as the physical, chemical and biological properties of myriocin and one of its derivatives, anhydromyriocin. The elucidation of its chemical structure is also reported. The compound appears to be too toxic for therapeutic purposes.

Eddy and Williamson1 obtained structures resembling intact protoplasts from cells of Saccharomyces after digestion of the cell-wall by enzymes from the gut of the snail Helix pomatia. This report was followed by a number of papers on the structural and physiological properties of the yeast protoplasts obtained by this procedure2–5.