共查询到20条相似文献,搜索用时 15 毫秒
1.
Cecilia Ximénez Emma I. Melendro Amado Gonzalez-Mendoza Ana Ma. García Anastasio Martínez Librado Ortiz-Ortiz 《Mycopathologia》1980,70(2):117-122
Different vaccination procedures to increase the mecha nisms of host resistance to Nocardia brasiliensis were studied in mice. When mice were challenged in the footpad, 2×108
N. brasiliensis 20 days after footpad inoculation with either viable or killed N. brasiliensis, the mice demonstrated significant resistance to infection when compared with noninfected and nonimmunized mice. The degree of resistance seems to be correlated with the delayed-type hypersensitivity response in the vaccinated animals. Vaccination with another acid-fast bacilli, BCG, afforded both a mild protection and low DTH reactivity. Antibody levels to Nocardia were similar in either Nocardia- or BCG- treated groups indicating that they do not play an important role in resistance to infection by N. brasiliensis. 相似文献
2.
Linda L. Blackall Professor Kevin C. Marshall 《Journal of industrial microbiology & biotechnology》1989,4(3):181-187
Summary Cultures ofNocardia amarae give rise to cell-stabilized foams in a laboratory scale foaming apparatus. The organism produces a surfactant and the cells are very hydrophobic; factors which, in terms of froth flotation theory, are essential for foam production and transport of the cells from the aqueous to the bubble phase. The addition of montmorillonitic clay to the culture prior to foaming prevents foam stabilization. The results obtained suggest the formation of a salt-dependent, reversible, bacterium-montmorillonite complex which prevents transport of cells to the bubble phase. 相似文献
3.
Nocardia polychromogenes (saprophytic) and Nocardia asteroides (pathogenic) showed characteristic patterns in changes of cellular lipids during growth. Total lipids and total phospholipids decreased with the age of the culture in the saprophytic strain, whereas in the pathogenic strain total lipids increased throughout the culture period and the total phospholipids decreased in the late stationary phase. The decrease in total phospholipids in saprophytic strain was reflected in the individual phosphatides. In the pathogenic strain, the phosphatidylinositomannoside content doubled in early stationary phase. Differences were observed in fatty acid composition of phosphatides at various stages of growth, but the ratio of saturated to unsaturated fatty acids remained unaltered. 相似文献
4.
Like many other bacteria, Nocardia sp. possess acid phosphatase activity. In N. brasiliensis, a human and animal pathogen, this activity was resolved into two enzyme forms by native gel electrophoresis. One (isozyme I) was partially purified and characterized. It exhibited an estimated molecular weight on SDS-PAGE of 50 kDa, a pH optimum of 5.2, and a Km value of 1.25 mM for p-nitrophenylphosphate. The N. brasiliensis enzyme was stable at 4 °C for at least 24 h, but readily inactivated at 60 °C. Ammonium molybdate, sodium fluoride and L-(+)-tartrate were found to be potent inhibitors of the enzyme. Although its function is presently unknown, by analogy to other bacterial systems it could be envisioned to play an important role in the physiology and pathogenicity of the microorganism. 相似文献
5.
Méndez-Tovar LJ Mondragón-González R Vega-López F Dockrell HM Hay R López-Martínez R Manzano-Gayosso P Hernández-Hernández F Padilla-Desgarennes C Bonifaz A 《Mycopathologia》2004,158(4):407-414
IFN-γ, TNF-α, IL-4, IL10 and IL-12 concentrations in the supernatant of peripheral blood mononuclear cell (PBMC) cultures and the
in vitro proliferation of PBMC were studied in 25 patients with actinomycetoma caused by Nocardia brasiliensisand in 10 healthy controls from endemic zones. Cell cultures were stimulated by a N. brasiliensiscrude cytoplasmic antigen (NB) and five semi-purified protein fractions (NB2, NB4, NB6, NB8, and NB10) separated by isoelectric.
Phytohemagglutinin (PHA) and purified protein derivative (PPD) of Mycobacterium tuberculosiswere used as control antigens. Skin tests were performed by injecting 0.1 ml of candidin and PPD intradermally (ID). Patients
showed a poor response to tuberculin, while their response to candidin was more than two fold greater than that observed in
the controls. Cell proliferation showed no statistically significant differences in either group. IFN-γ production was higher in the healthy controls than in the patients, whereas TNF-α secretion was slightly higher in the patients’ cultures. IL-4 was detected in the patients’ cultures but not in the controls.
IL-10 and IL-12 were present at low concentrations in both groups. These results suggest that patients with actinomycetoma
show normal antigen recognition, but with low IFN-γ production, and higher concentrations of IL-4, IL-10 and TNF-α in the patients’ PBMC cultures, indicating that they probably have a Th2 type of immune response. 相似文献
6.
Summary
Nocardia mediterranei strain LBG A3136 contains the 23.7 kb element pMEA100 in a chromosomally integrated form as well as in the free state (Moretti et al. 1985). The integrated form of this element can be excised precisely from the Nocardia chromosome without any accompanying rearrangements in flanking chromosomal DNA. After transfer into plasmid-free mutant strains, pMEA100 reintegrates site specifically into its original chromosomal locus. The exact mapping of the pMEA100 integration site was accomplished by restriction analysis and DNA sequencing. The attachment site of pMEA100, the junctions of its integrated form and plasmid-free chromosomal DNA of N. mediterranei contain an identical 47 bp long sequence which is probably required for site-specific recombination connected with integration and excision of pMEA100. Only one such sequence was found in the chromosome of pMEA100-free N. mediterranei derivatives as suggested by the single integration locus. 相似文献
7.
Francisca Hernández-Hernández Rubén López-Martínez Luis J. Méndez-Tovar Patricia Manzano-Gayosso 《Mycopathologia》1995,132(2):79-85
As actinomycetoma is more frequent in males than in females, the possibility that hormones might modify theNocardia brasiliensis growth and the course of experimental actinomycetoma was explored. FiveN. brasiliensis strains were grown on Sabouraud agar containing estradiol, progesterone or testosterone, in 3 different concentrations. Colony diameters were measured weekly for 7 weeks.N. brasiliensis strains were also grown in Sabouraud broth containing hormones. Glucose concentration was measured weekly for 6 weeks. Finally, experimental actinomycetoma was produced in male and female hormone-treated mice. Invasion rate, plantar pad diameter and positive retrocultures were assessed. In vitro experiments showed that progesterone and testosterone inhibitN. brasiliensis growth, manifested by lower colony diameters and greater glucose concentrations. In vivo experiments demonstrated that estradiol limits actinomycetoma development. Progesterone and testosterone induced greater diameters of inoculated plantar pads and greater invasion rates with greater positive culture numbers than estradiol. Results partially explain the resistance of females to actinomycetoma. 相似文献
8.
The efficacy of immobilized Saccharomyces cerevisiae (biomatrix) for the sorption of different metal ions and its potential applications in nuclear waste treatment were investigated. The sorption of radionuclides such as 233U, 241Am, 144Ce, 137Cs and 90Sr was studied under different experimental conditions. More than 95% sorption of UO2
2+, Pu4+, Am3+ and Ce3+ could be obtained in the pH range 1 to 2 of the aqueous solutions. However the sorption of Cs+ and Sr2+ were negligible under the similar experimental conditions. The infrared spectra and scanning electron microscopic images of the control and uranium-bearing biomatrix were studied to understand the chemistry of metal uptake by this biomatrix. 相似文献
9.
Castro-Matteotti B Vera-Cabrera L Ocampo-Candiani J Rendón A Salinas-Carmona MC Welsh O 《Mycopathologia》2008,165(3):127-134
The ability of culture-filtrate proteins to induce a cellular immune response in infected mice and humans was investigated.
A crude extract culture filtrate of Nocardia brasiliensis (CFA) and five semi-purified CFA fractions (P1, P2, P3, P4, P5) were used to stimulate BALB/c mice spleen-cell cultures.
The animals were divided into three groups: the first group was infected with 1 × 107 CFU of N. brasiliensis in the footpad, the second group was immunized with heat-killed bacteria, and the third was injected with sterile saline.
IFN-γ, IL-1α, and IL-4 concentrations were determined in culture supernatants. Protein fractions eliciting IFN-γ production
in mice, as well as the CFA, were used to stimulate IFN-γ production and in vitro cell proliferation assays with peripheral
blood mononuclear cells of patients with actinomycetoma by N. brasiliensis, individuals with pulmonary tuberculosis, and healthy controls. In mice, CFA and three of the protein fractions (P3, P4 and
P5) induced significant IFN-γ production in the infected group. In humans, only the CFA-induced IFN-γ production and cell
proliferation in the group of patients with actinomycetoma. There was no stimulation in tuberculosis patients nor healthy
controls. These results suggest that some culture-filtrate antigens are recognized by patients with active actinomycetoma
and do not cross-react with M. tuberculosis antigens, being therefore potential candidates to develop a diagnostic test. 相似文献
10.
Kageyama Akiko Sato Hiroko Nagata Matsuo Yazawa Katsukiyo Katsu Masakazu Mikami Yuzuru Kamei Katsuhiko Nishimura Kazuko 《Mycopathologia》2003,156(3):187-192
Nocardia sp. IFM 0896, an actinomycete with biochemical characteristics that differed from Nocardia brasiliensis, was isolated from a 71-year-old Japanese man with a history of tuberculosis and cancer. Although the isolate was tentatively identified as N. brasiliensis, the morphological and physiological characteristics of strain IFM 0896 were different from those of N. brasiliensis IFM 0236T. The results of 16S rRNA gene sequence phylogenies and PCR-RFLP analysis of a heat shock protein revealed that Nocardia sp. IFM 0896 belongs to the species N. pseudobrasiliensis. This is the first clinical isolation report of N. pseudobrasiliensis in Japan.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
11.
Xu P Li WJ Tang SK Jiang Y Gao HY Xu LH Jiang CL 《Systematic and applied microbiology》2006,29(4):308-314
A novel actinomycete strain YIM 33378T was isolated from a soil sample collected from Lijiang, Yunnan Province, China. Based on the results of phenotypic and genotypic characteristics, strain YIM 33378T should be assigned to a new species of the genus Nocardia, for which the name Nocardia lijiangensis sp. nov. is proposed. The type strain is YIM 33378T (= CCTCC AA 204005T = KCTC 19028T). The GenBank accession number for the sequence reported in this paper is AY779043. 相似文献
12.
Li WJ Jiang Y Kroppenstedt RM Xu LH Jiang CL 《Systematic and applied microbiology》2004,27(3):308-312
A novel actinomycete strain, designated YIM 30243T, was isolated from a soil sample in Yunnan Province, China. Based on the results of phenotypic and genotypic characteristics, strain YIM 30243T should be assigned to a new species of the genus Nocardia, for which the name Nocardia alba sp. nov. is proposed. The type strain is YIM 30243T (= CCTCC AA001030T = DSM 44684T). 相似文献
13.
Nocardia farcinica is a Gram positive, filamentous bacterium, and is considered an opportunistic pathogen. In this study, the highly expressed
genes in N. farcinica were predicted using the codon adaptation index (CAI) as a numerical estimator of gene expressivity. Using ribosomal protein
(RP) genes as references, the top ∼
∼10% of the genes were predicted to be the predicted highly expressed (PHX) genes in N. farcinica using a CAI cutoff of greater than 0.73. Consistent with earlier analysis of Streptomyces genomes, most of the PHX genes in N. farcinica were involved in various ‘house-keeping’ functions important for cell growth. However, 15 genes putatively involved in nocardial
virulence were predicted as PHX genes in N. farcinica, which included genes encoding four Mce proteins, cyclopropane fatty acid synthase which is involved in the modification
of cell wall which may be important for nocardia virulence, polyketide synthase PKS13 for mycolic acid synthesis and a non-ribosomal
peptide synthetase involved in biosynthesis of a mycobactin-related siderophore. In addition, multiple genes involved in defense
against reactive oxygen species (ROS) produced by the phagocyte were predicted with high expressivity, which included alkylhydroperoxide
reductase (ahpC), catalase (katG), superoxide dismutase (sodF), thioredoxin, thioredoxin reductase, glutathione peroxidase, and peptide methionine sulfoxide reductase, suggesting that
combating against ROS is essential for survival of N. farcinica in host cells. The study also showed that the distribution of PHX genes in the N. farcinica circular chromosome was uneven, with more PHX genes located in the regions close to replication initiation site. The results
provided the first estimates of global gene expression patterns in N.␣farcinica, which will be useful in guiding experimental design for further investigations.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
14.
Herminia I. Pérez Héctor Luna Norberto Manjarrez Aida Solís 《Biotechnology letters》2001,23(18):1467-1472
Whole cells of Nocardia corallina B-276 oxidized enantioselectively racemates of arylethyl carbinols, at 0.5 mM, to give ketones in yields from 4 to 97% (w/w) and the unreacted alcohols showing enantiomeric excess ranging from 5 to > 99%. The configuration of the resulting alcohol is (R). 相似文献
15.
Usama Beshay Desouky Abd-El-Haleem Hassan Moawad Sahar Zaki 《Biotechnology letters》2002,24(15):1295-1297
Acinetobacter sp. strain W-17, immobilized on porous sintered glass completely degraded 500 mg phenol l–1 in 40 h, but free cells required 120 h for this to be achieved. Immobilized cells can be used 7 times without losing their activity. 相似文献
16.
Enhanced levan production using chitin-binding domain fused levansucrase immobilized on chitin beads
Chung-Jen Chiang Jen-You Wang Po-Ting Chen Yun-Peng Chao 《Applied microbiology and biotechnology》2009,82(3):445-451
Levan is a homopolymer of fructose which can be produced by the transfructosylation reaction of levansucrase (EC 2.4.1.10)
from sucrose. In particular, levan synthesized by Zymomonas mobilis has found a wide and potential application in the food and pharmaceutical industry. In this study, the immobilization of
Z. mobilis levansucrae (encoded by levU) was attempted for repeated production of levan. By fusion levU with the chitin-binding domain (ChBD), the hybrid protein was overproduced in a soluble form in Escherichia coli. After direct absorption of the protein mixture from E. coli onto chitin beads, levansucrase tagged with ChBD was found to specifically attach to the affinity matrix. Subsequent analysis
indicated that the linkage between the enzyme and chitin beads was substantially stable. Furthermore, with 20% sucrose, the
production of levan was enhanced by 60% to reach 83 g/l using the immobilized levansucrase as compared to that by the free
counterpart. This production yield accounts for 41.5% conversion yield (g/g) on the basis of sucrose. After all, a total production
of levan with 480 g/l was obtained by recycling of the immobilized enzyme for seven times. It is apparent that this approach
offers a promising way for levan production by Z. mobilis levansucrase immobilized on chitin beads. 相似文献
17.
Walther Johannssen Holger Gerberding Manfred Rohde Christiane Zaborosch Frank Mayer 《Archives of microbiology》1991,155(3):303-308
The soluble NAD-dependent hydrogenase (hydrogen-NAD oxidoreductase, EC 1.12.1.2), consisting of four non-identical subunits, was isolated from Alcaligenes eutrophus H16 and from Nocardia opaca 1b and analyzed by a HPLC gel permeation technique and electron microscopy. The tetrameric enzyme particles from both origins, as determined from negatively stained electron microscopic samples, were found to be elongated and very similar in shape and size. The A. eutrophus enzyme was measured in more detail. It exhibited dimensions of 12.7 nm by 5.5 nm (axial ratio 2.3:1). Dissociation into smaller particles and unspecific aggregation combined with partial inactivation were observed in the presence of the inhibitor NADH. Kept in buffer without added nickel, the enzyme was partially dissociated. Reassociation of tetramers without restored enzyme activity was achieved by addition of 0.5 mM NiCl2. A working model for the structural organization of the tetrameric enzyme particle is presented. 相似文献
18.
Jinxia Yang Minyan He Gejiao Wang 《World journal of microbiology & biotechnology》2009,25(9):1579-1587
Chromate-reducing microorganisms with the ability of reducing toxic chromate [Cr(VI)] into insoluble trivalent chromium [Cr(III)]
are very useful in treatment of Cr(VI)-contaminated water. In this study, a novel chromate-reducing bacterium was isolated
from Mn/Cr-contaminated soil. Based on morphological, physiological/biochemical characteristics and 16S rRNA gene sequence
analyses, this strain was identified as Intrasporangium sp. strain Q5-1. This bacterium has high Cr(VI) resistance with a MIC of 17 mmol l−1 and is able to reduce Cr(VI) aerobically. The best condition of Cr(VI) reduction for Q5-1 is pH 8.0 at 37°C. Strain Q5-1
is also able to reduce Cr(VI) in resting (non-growth) conditions using a variety of carbon sources as well as in the absence
of a carbon source. Acetate (1 mmol l−1) is the most efficient carbon source for stimulating Cr(VI) reduction. In order to apply strain Q5-1 to remove Cr(VI) from
wastewater, the bacterial cells were immobilized with different matrices. Q5-1 cells embedded with compounding beads containing
4% PVA, 3% sodium alginate, 1.5% active carbon and 3% diatomite showed a similar Cr(VI) reduction rates to that of free cells.
In addition, the immobilized Q5-1 cells have the advantages over free cells in being more stable, easier to re-use and minimal
clogging in continuous systems. This study provides potential applications of a novel immobilized chromate-reducing bacterium
for Cr(VI) bioremediation. 相似文献
19.
The mycolic acid compositions of Nocardia rubra and related bacteria grown in media containing different concentrations of antituberculous isonicotinic acid hydrazide (INH) were determined in detail by gas chromatography-mass spectrometry. On the basis of molecular species composition, average carbon numbers of mycolic acids were calculated. In Nocardia rubra, N. lutea and Rhodococcus rhodochrous IFO-13161, the ratio of mycolic to non-mycolic fatty acids and the average carbon numbers of mycolic acids were decreased at the INH concentrations of higher than 1 g/ml, paralleling with the significant inhibition of growth. In above three species the synthesis of longer chain mycolic acids (longer than C44 or C46) was inhibited more significantly than shorter homologues such as C38 or C40. In contrast, neither growth inhibition nor change in corynomycolic acid composition was observed in Corynebacteria xerosis and Rhodococcus rhodochrous IFO-13165 at the concentration region of INH up to 100 g/ml. The direct mass fragmentographic analysis of the trimethylsilylated (TMS) derivatives of mycolic acid methyl esters, monitoring [M-15] ions of individual molecular species, revealed that the chain shortening of total mycolic acid molecule by INH occurred more greatly in more highly unsaturated subclasses than in less unsaturated subclasses. Furthermore, mass fragmentographic analysis, monitoring fragment ions (A) and (B), due to straight chain and branched chain alkyl units, respectively, demonstrated the inhibition of mycolic acids was not attributed to the shortening of -alkyl chain, but to the inhibition of chain elongation of C28 to C32 straight chain meromycolic acids. It was also indicated the amounts of trehalose mono- and di-mycolate (cord factor) decreased significantly with the addition of INH (1 to 20 g/ml) in the above strains. From the results obtained above, INH appeared to inhibit the synthesis of mycolic acids longer than C44 or C46 specifically by inhibiting chain elongation or desaturation of precursor long chain fatty acids longer than C28 or C30. 相似文献
20.
Hisayuki Komaki Natsuko Ichikawa Akira Hosoyama Azusa Takahashi-Nakaguchi Tetsuhiro Matsuzawa Ken-ichiro Suzuki Nobuyuki Fujita Tohru Gonoi 《BMC genomics》2014,15(1)