No abstract available.
Staphylococcus aureus* ; Staphylococcus* ; Streptomyces*

The antimicrobial agents reduced infectious diseases significantly. However, antibiotic resistance has followed for almost every antimicrobial agent. Especially, Staphylococcus aureus was one of the most notorious for the multidrug resistance. Streptomyces sp. 681 has been selected for antibiotic-producing strain against methicillin-resistant Staphylococcus aureus (MRSA) from 1,000 strains of Actinomycetales which had been isolated from soil. In antimicrobial susceptibility test, all of the test strains were susceptible to vancomycin. However, most strains of Staphylococcus aureus were found to be resistant to methicillin. Ninety eight (75%) strains out of 129 strains showed multiple resistance pattern to more than 5 antimicrobial agents. The MIC values of the purified antibiotic (K-681) were 1-32 ug/ml against Gram-positive bacteria compared to >128 ug/ml against Grarn-negative bacteria or fungi. The MIC was 8 ug/ml for 90% of the 129 clinical isolates of S. aureus. The antibiotic showed no cytotoxicity against P 388, HeLa, and S180 at the concentration of 500 ug/ml.
Actinomycetales ; Anti-Infective Agents ; Bacteria ; Communicable Diseases ; Drug Resistance, Microbial ; Drug Resistance, Multiple ; Fungi ; Gram-Positive Bacteria ; Methicillin ; Methicillin-Resistant Staphylococcus aureus ; Soil ; Staphylococcus aureus* ; Staphylococcus* ; Streptomyces* ; Vancomycin

In the present study, culture conditions to secrete proteinases from C. albicans, C. tropicalis and C. parapsilosis were examined. All three Candida species were found to secrete proteinases from acceleration phase to stationary phase, although the proteinase activities in culture filtrate were maximal during late exponential or early stationary phase. The proteinase activity in the culture filtrate of C. albicans cells grown at 30'C, was much higher than those grown at either 20 or 37'C. In culture of C. tropicalis and C. parapsilosis, the highest activity was found in culture filtrate grown at 37C. C. albicans secreted proteinases well in medium at initial pH 4.0-7.0. The optimal initial pH of medium for proteinase secretion was 7.0 for C. tropicalis and 5.0-6.0 for C. parapsilosis. All three Candida species secreted proteinases to greater amount in aerobic state. The most effective carbon source for proteinase secretion was xylose, glucose, maltose and sucrose for C. albicans, xylose for C. tropicalis and trehalose for C. parapsilosis. The effects of proteins, hydrolyzed proteins, ammonium sulfate as a sole nitrogen source on proteinase secretion were examined. Bovine serum albumin was the most effective nitrogen source of those tested and a little proteinase activity was detected in the culture filtrates when yeast cells were incubated in the medium containing ammonium sulfate. C. parapsilosis secreted proteinases to greater amount than the other Candida species in all nitrogen sources under study, indicating that C. parapsilosis proteinase would not be a inducible but a constitutive enzyme.
Acceleration ; Ammonium Sulfate ; Candida albicans* ; Candida* ; Carbon ; Glucose ; Hydrogen-Ion Concentration ; Maltose ; Nitrogen ; Peptide Hydrolases* ; Serum Albumin, Bovine ; Sucrose ; Trehalose ; Xylose ; Yeasts

No abstract available.
Streptomyces*

The fibrillar coat of Candida albicans is of interest as its significance in antigenicity, antiphagocytosis, and adherence to host tissues. The partial biochemical properties and ultrastructure of fibrillar coat induced by rabbit sera were examined. The induced fibrillar layer was destroyed by treatments of lyticase, proteinase K and dithiothreitol. The total protein concentration of fibrillar cell wall lysate was higher than that of non-fibrillar cell wall lysate, but the total sugar concentration was similar. On SDS-PAGE analysis, the protein profiles between in fibrillar cells and in non-fibrillar cells were shown to be different. In fibrillar cells, the major bands of cell wall lysate were 83, 66, 54, 47, 33, and 26 kDa in dithiothreitol-treated lysate. The proteins of 26 and 19 kDa were predominant in lyticase-treated lysate. Although the fibrillar thickness and protein amount of cell wall lysate were increased in according to the incubation time, the protein profiles did not changed. These results suggest that the proteins of 83, 66, 54, 47, 33, 26, and 19 kDa may be major constituents of fibrillar coat in C. albicans.
Candida albicans* ; Candida* ; Cell Wall ; Dithiothreitol ; Electrophoresis, Polyacrylamide Gel ; Endopeptidase K

BACKGROUND: Disialoganglioside GD2 is a tumor-associated antigen that is overexpressed on tumor cells of neuroectodermal origin, such as melanoma, small cell lung carcinoma and neuroblastoma. Immunity against GD2 has anti-tumor activities, but GD2 is poorly immunogenic. Anti-idiotypic antibodies that mimic GD2 may induce more effective immune responses than GD2 antigen itself, because they are protein antigens and are known to be able to break immune tolerance. In our previous study, we produced anti-idiotypic antibodies mimicking GD2 (3A4 and 3H9), which induced humoral immunity. However, cellular immunity is essential to eradicate tumor cells in vivo as well as humoral immunity. In the present study, we investigated whether these anti-idiotypic antibodies 3A4 and 3H9 could induce cellular immunes responses. METHODS: BALB/C mice were immunized with anti-idiotypic antibody 3A4 or 3H9, or normal mouse IgG as a negative control. Lymphoproliferative responses, cytokine production responses, and delayed-type hypersensitivity reactions were measured in mice immunized with the anti-idiotypic antibodies. RESULTS: Both the anti-idiotypic antibody 3A4 and 3H9 induced GD2-specific lymphoproliferative responses and IFN-gamma production of lymph node lymphocytes in BALB/C mice. Only anti-idiotypic antibody 3H9 induced significant GD2-specific delayed-type hypersensitivity in the mice. CONCLUSION: These results show that anti-idiotypic antibodies 3A4 and 3H9 have the potentiality of inducing GD2-specific cellular immune responses that cannot be induced by the native antigen GD2 itself.
Animals ; Antibodies, Anti-Idiotypic* ; Hypersensitivity ; Immune Tolerance ; Immunity, Cellular* ; Immunity, Humoral ; Immunoglobulin G ; Lymph Nodes ; Lymphocytes ; Melanoma ; Mice ; Neural Plate ; Neuroblastoma ; Small Cell Lung Carcinoma

To investigate whether anti-Candida proteinase antibody could be a diagnostic marker, we examined seroreactivity to proteinase in sera from 90 healthy controls and 8 of C. albicans culture-positive patients. Previously we purified proteinases of C. albicans, C. tropicalis, and C. parapsilosis using a series of chromatographic steps consisting of DEAE- Sepharose, Sephacryl S-200, and size-exclusion HPLC. ELISA and Western blot technique were adopted to examine seroreactivity of C. albicans proteinase with sera. On ELISA, the seroreactivities of healthy controls and C. albicans-cultured patients were 0.601 +- 0.014 (mean+SEM), and 0.695 +- 0.079, respectively (P=0.084, t-test). In C. albicans-cultured patients, the positive rate was 62.5% (5/8) and the positive rate of healthy controls was 39% (35/90). On Western blot analysis, C. albicans proteinase molecule was blotted by all sera tested. But the intensity of blotted band was different with the same dilution of sera; the intensity of C. albicans proteinase molecule band blotted by 2 sera of 3 healthy control's sera was distinctively lower than that by C. albicans-cultured patients sera. However, all sera including C. albicans-cultured patient's sera did not blot the proteinase secreted by C. tropicalis and C. parapsilosis. It is necessary to collect sequential sera of patients with candidiasis and to establish a cut-off value for ELISA or serum dilution for Western blot analysis that will give reliable test sensitivity and specificity.
Blotting, Western ; Candida albicans* ; Candida* ; Candidiasis ; Chromatography, High Pressure Liquid ; Enzyme-Linked Immunosorbent Assay ; Humans ; Peptide Hydrolases ; Sensitivity and Specificity ; Sepharose

No abstract available.
Candida albicans* ; Candida*

All of the methicillin-resistant Staphylococcus aureus (MRSA) strains exhibit resistance to oxacillin by producing PBP2a encoded by mecA, whereas methicllin-susceptible Staphylococcus aureus (MSSA) strains do not. To investigate phenotypic differences other than oxacillin resistance level in responses to oxacillin between MSSA and MRSA, we compared alterations of viability and ultrastructure of MSSA by oxacillin treatment with those of MRSA. When MSSA and MRSA strains were exposed to oxacillin of their respective MICs, and then were assayed for viability and observed by transmission electron microscope, increase in thickness of cell wall was more prominent in MRSA strains than in MSSA strains, while decrease in number of surviving cells was more evident and change in morphology of growing cross wall was greater in MSSA strains than in MRSA strains. It is assumed that these different responses to oxacillin between MSSA and MRSA strains may be due to activation of some PBP2a unbound to oxacillin. In conclusion, MSSA and MRSA showed different functional and morphological responses to oxacillin, although they were treated with oxacillin of concentrations that respectively inhibit their proliferation.
Adenosine ; Cell Wall ; Electrons ; Methicillin-Resistant Staphylococcus aureus ; Oxacillin ; Staphylococcus aureus

For direct identification of Candida albicans from other Candida species, the chlamydospore formation and the mycelial transition induced by high temperature and by sera were examined in 198 Candida isolates. The germ tubes of C. albicans developed early at 30 min in high temperature-induction, but at 60 min in serum-induction. C. albicans generated germ tubes well at concentrations lower than 2 x 10(7) cells/ml, but the germ tube formation was markedly restrained at concentrations higher than 4 x 10(7) cells/ml. In a serum-free, yeast extract-peptone-dextrose (YEPD) medium, C. albicans grew as a yeast form at 30 degrees C and as a mycelial form at 35-42 degrees C. Mycelial development was maximal at 37 degrees C in serum and at 39 degrees C in YEPD. Germ tubes were formed within 30 min in YEPD at 39 degrees C, but after 60 min in serum at 37 degrees C. Our examination showed that the 39 degrees C-induced germ tube formation tests were very reliable (sensitivity 100%, specificity 100%) at discerning C. albicans from other Candida species. These results suggest that the high temperature-induced germ tube formation testing could be a useful identification method of C. albicans in clinical laboratories.
Candida albicans/physiology ; Candida albicans/isolation & purification* ; Sensitivity and Specificity ; Temperature