First human case of nocardiosis caused by Nocardia pseudobrasiliensis in Japan

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 0236^T. 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.     

Nocardia aobensis Sp. Nov., isolated from patients in Japan

Five clinical isolates, strains IFM 0137, 0372(T), 0496, 0556, and 0952, were provisionally assigned to the genus Nocardia based on morphological criteria. Nearly complete 16S rDNA sequences were determined for these strains. These data showed that they are most similar to that of Nocardia africana, Nocardia cerradoensis and Nocardia veterana. However, DNA-DNA relatedness data showed that the five strains were of a single species and were distinguishable from N. africana, N. cerradoensis and N. veterana. Therefore, these strains represent a new species within the genus Nocardia. The designation of these five strains is Nocardia aobensis sp. nov. The type strain is IFM 0372(T) (=NBRC 100429(T)=JCM 12352(T)=DSM 44805(T)).     

Differentiation of nocardia species by PCR-randomly amplified polymorphic DNA fingerprinting

Representatives of fifteen validly described and three non-validly described species of Nocardia were assigned to nineteen groups based on an optimised PCR-randomly amplified polymorphic DNA fingerprinting technique. Species specific banding patterns were recognised for the representatives of N. brasiliensis, N. crassostreae, N. farcinica, N. otitidiscaviarum and N. seriola. Unique banding patterns were also seen for the type strains of N. brevicatena, N. carnea, N. salmonicida, N. uniformis and N. vaccinii, and for the single representatives of "N. fusca", "N. pseudosporangifera", and "N. violaceofusca". More than one banding pattern was detected for the N. asteroides, N. flavorosea, N. nova, N. pseudobrasiliensis and N. transvalensis strains though in the case of the representative strains of N. nova and N. transvalensis the patterns were similar for each of these species. The results are in line with current trends in nocardial systematics thereby indicating that PCR-randomly amplified polymorphic DNA fingerprinting provides valuable data for the classification and identification of pathogenic nocardiae to the species level.     

Brasilicardins B-D, new tricyclic terpenoids [correction of terpernoids] from actinomycete Nocardia brasiliensis

Three new tricyclic terpenoids, brasilicardins B-D (2-4), were isolated together with brasilicardin A (1), a potent immunosuppressive compound, from the cultured broth of a pathogenic actinomycete Nocardia brasiliensis IFM0406, and the structures and stereochemistry were determined by spectroscopic data and a single crystal X-ray diffraction analysis. The immunosuppressive and cytotoxic activities of 2-4 were examined in the comparison with 1.     

Nocardia testaceus sp. nov. and Nocardia senatus sp. nov., isolated from patients in Japan

Two actinomycete strains isolated from sputum between 1999 and 2001 in Japan were provisionally assigned to the genus Nocardia based on morphological criteria. These isolates were further studied in order to determine their specific taxonomic status. Detailed chemotaxonomic characterization and 16S rDNA gene sequence analysis of these isolates also confirmed that they belong to the genus Nocardia. The 16S rDNA sequence data of the two strains showed that they are most similar to that of Nocardia carnea and Nocardia flavorosea. However, DNA-DNA relatedness data showed that the two strains could be distinguished from N. carnea and N. flavorosea and therefore represented two new species within the genus Nocardia. The designation of the two isolated strains are Nocardia testaceus for IFM 0937(T) (=JCM 12235(T), DSM 44765(T)) and Nocardia senatus for IFM 10088(T) (=JCM 12236(T), DSM 44766(T)).     

Characterization of Nocardithiocin Derivatives Produced by Amino Acid Substitution of Precursor Peptide notG

International Journal of Peptide Research and Therapeutics - Nocardithiocin is a thiopeptide compound produced by the pathogenic actinomycete Nocardia pseudobrasiliensis that displays activity...     

Fatty acid composition of the lipids of streptomycetes and their nocardia-like mutants

The models "population--Nocardia-like spontaneous mutants" for 14 cultures of Streptomycetes and Streptoverticillium were used to assess the fatty acid composition of lipids as a criterion for generic differentiation of Streptomyces and Nocardia cultures. The composition of fatty acids in the Nocardia-like mutant Str. kanamyceticus RIA-771 was found to be identical with that of Nocardia asteroides RIA-43 and Nocardia brasiliensis RIA-440, i. e. generic chemotaxonomic traits "overlapped" in the process of spontaneous intraspecial variability. In different strains of one and the same species as well as in five different species, the quantitative composition of fatty acids either hardly changed in the process of intraspecial variability or the ratio between fatty acids changed, so that Nocardia-like mutants resembled typical cultures of the Nocardia genus in this characteristics. The results suggest that the quantitative composition of fatty acids of lipids cannot be regarded as a sufficiently reliable criterion for generic differentiation of Steptomyces and Nocardia cultures. This trait should be used only for additional characterization of cultures.     

Complete genome sequence of Nocardia brasiliensis HUJEG-1

In Mexico, actinomycetoma is mainly caused by Nocardia brasiliensis, which is a soil inhabitant actinobacterium. Here, we report for the first time the draft genome of a strain isolated from a human case that has largely been found in in vitro and experimental models of actinomycetoma, N. brasiliensis HUJEG-1.     

Purification and partial characterization of a Nocardia brasiliensis extracellular protease.

Nocardia brasiliensis possess proteolytic activities that can be readily detected in a variety of media. In a modified formulation of a growth medium originally used for Streptomyces aureofaciens, N. brasiliensis was found to secrete proteolytic enzymes, one of which was capable of hydrolyzing casein. This enzyme was purified to homogeneity from cell-free culture filtrates of N. brasiliensis. The purification procedure included ion-exchange chromatography on carboxymethyl-Sepharose, gel filtration on Sephadex G-100, and affinity chromatography, using a hemoglobin-Sepharose resin. The molecular weight of the N. brasiliensis protease was found to be 25,000 by gel filtration and 35,000 by sodium dodecyl sulfate-discontinuous gel electrophoresis. The enzyme is inhibited by o-phenanthroline and 8-hydroxyquinoline-5-sulfonic acid but is not affected by EDTA. Average values for its kinetic parameters were 0.288 mumol of hemoglobin solubilized per min per mg of enzyme for Vmax and 0.76 mM for Km, using hemoglobin as the substrate.     

Thiols in nitric oxide synthase-containing Nocardia sp. strain NRRL 5646

Mycothiol (MSH) [1-D-myo-inosityl-2-(N-acetyl-l-cysteinyl)amido-2-deoxy-alpha-D-glucopyranoside], isolated as the bimane derivative, was established to be the major thiol in Nocardia sp. strain NRRL 5646, a species most closely related to Nocardia brasiliensis strain DSM 43758(T). Thiol formation and detection of MSH-dependent formaldehyde dehydrogenase activity in cell extracts are relevant to the possible modulation of nitric oxide toxicity generated by strain NRRL 5646.     

Inactivation of kanamycin A by phosphorylation in pathogenic Nocardia.

Among the five species of pathogenic Nocardia, i.e., N. asteroides, N. brasiliensis, N. farcinica, N. nova and N. otitidiscaviarum, all strains of N. brasiliensis and N. farcinica showed resistance to an aminoglycoside antibiotic, kanamycin A, showing the MIC (minimum inhibitory concentration) values of more than 100 micrograms/ml. This species-specific difference in sensitivity was found to be explained by the production of an inactivation enzyme, aminoglycoside 3'-phosphotransferase APH(3'). Structural studies by mass and NMR spectroscopy on the inactivated substance produced by a cell-free extract of the Nocardia confirmed the conversion of kanamycin A to an inactive substance, kanamycin A 3'-phosphate. The MIC values of N. otitidiscaviarum and N. nova for kanamycin A, on the other hand, ranged from 0.78 micrograms/ml to 100 micrograms/ml, and both species were non-producers of APH(3'). Sensitivity to the antibiotic and APH(3') productivity of N. asteroides varied depending on the strain.     

Immunodiffusion studies of some Nocardia strains

Forty-three strains of Nocardia, one of Actinomadura and two of Nocardiopsis were studied using the comparative immunodiffusion technique. Three reference precipitation systems were employed: one represented Nocardia asteroides N10, one N. asteroides ATCC 19247, and one N. otitidis-caviarum ATCC 14629. One tight cluster was formed by the N. otitidis-caviarum strains and another tight cluster was formed by some of the N. asteroides strains studied. However, other strains of N. asteroides were distinct from the latter cluster. Furthermore, N. asteroides ATCC 19247, which is the type strain, differed from most ot the N. asteroides strains tested. Strains of the species N. asteroides, N. brasiliensis, N. farcinica and N. otitidis-caviarum were found to be closely related, while N. amarae strains differed slightly from this group. The strains referred to Actinomadura and Nocardiopsis were clearly distinct from the three Nocardia reference strains; nevertheless, three antigens common to these genera were revealed.     

Experimental pathogenicity of isolates of Nocardia asteroides, Nocardia brasiliensis and Nocardia caviae from different sources

The experimental pathogenicity of 14 isolates of Nocardia brasiliensis, 15 of N. asteroides, and 5 of N. caviae was investigated for the white Swiss mice inoculated intraperitoneally and in the foot pad, and for the guinea-pig and the hamster (Mesocricetus auratus) both inoculated intratesticularly. The guinea-pig was remarkably sensitive to N. asteroides, with an apparent relationship between pathogenicity and thermotolerance, confirming previous observations. Mice were in general less susceptible to this species. In both guinea-pigs and hamsters it was possible to observe typical granules with or without clubs. N. caviae was highly pathogenic for the guinea-pig and the hamster but no mycetomas were produced in the mice inoculated in the foot pad. Isolates of N. brasiliensis from natural sources were scarcely virulent for the different animals. Those of human origin produced significant lesions in the mice inoculated intraperitoneally with granules. Foot pad inoculation of mice with N. brasiliensis caused mycetomas in several animals.     

Mouse toxicity induced by lipids and cell walls isolated from actinomycetes

The possibility was examined that the toxicity induced in mice by Actinomadura madurae, 'Streptomyces pelletieri' and Nocardia brasiliensis was due to lipid and cell-wall constituents. Mice were inoculated intraperitoneally with heat-killed bacteria, lipid extracts and cell-wall preparations emulsified in mineral oil: toxicity was evaluated by recording weight loss and deaths. Killed cells and cell-wall preparations of all three actinomycetes produced a pronounced loss of body weight, tissue necrosis, splenomegaly, a granulomatous inflammation and sometimes death. Mice inoculated with lipid extracts from A. madurae and 'S. pelletieri' neither died nor showed toxic effects, but mice injected with lipids isolated from N. brasiliensis did suffer toxic effects. They showed more marked wasting symptoms than observed after inoculation of heat-killed bacteria or of the cell-wall preparation.     

Preliminary investigation of the use of the enzyme linked immunosorbent assay (ELISA) in the serodiagnosis of mycetoma.

Antibody levels in a small group of Sudanese patients with clinically diagnosed mycetoma, and control groups were measured by countercurrent immunoelectrophoresis (CIE) and enzyme linked immunosorbent assay (ELISA). Antigens were prepared from the following organisms: Streptomyces somaliensis, Actinomadura madurae, A. pelletieri, Nocardia brasiliensis and Madurella mycetomi. Positive reactions were obtained in clinical cases against the homologous antigens in both CIE and ELISA; all heterologous and control sera negative in CIE but produced some reaction particularly against N. brasiliensis and M. mycetomi antigens in ELISA.     

微生物诱导子对霉素PT95菌株菌核生物量和类胡萝卜素产率的影响

菌核是许多丝状真菌形成的一种休眠体。我们从土壤中分离到一株经鉴定属于Ｐｅｎｉｃｉｌｌｉｕｍｔｈｏｍｉｉｓｅｒｉｅｓ的ＰＴ95青霉菌株 ,该菌株能在固态培养基上形成大量坚硬的砂粒状的菌核 (直径约 30 0 μｍ)。ＰＴ95菌株的菌核与众不同之处在于可以积累以β 胡萝卜素为主的类胡萝卜素[1 ] 。菌核的形成 ,除了遗传因素外 ,还受多种因素影响 ,例如生长环境中的温度、水势 (Ｗａｔｅｒｐｏｔｅｎｔｉａｌ)、有机物成分等[2～ 4] 。Ｈａｗｋｅｒ[5] 认为对真菌的营养生长 (Ｖｅｇｅｔａｔｉｖｅｇｒｏｗｔｈ)有利的物质也对菌核生长有…     

Immunogenicity is unrelated to protective immunity when induced by soluble and particulate antigens from Nocardia brasiliensis in BALB/c mice

Cell-mediated immunity plays a major role in protection against intracellular microbes. Nocardia brasiliensis is a facultative intracellular pathogen that causes chronic actinomycetoma. In this work, we injected BALB/c mice with soluble P24 and particulate antigens from N. brasiliensis. A higher antibody titer and lymphocyte proliferation was induced by the particulate antigen than by the soluble antigen. However, five months after antigen injection, antibody concentration and lymphocyte proliferation were similar. An increase in CD45R and CD4 T cells was unrelated to protective immunity. Active immunization with soluble or particulate antigens induced complete protection during the primary immune response. This protective response was IgM mediated. The higher immunogenicity was not related to protective immunity since the particulate antigen induced protection similar to the soluble antigen. Using particulate antigens for vaccination guarantees a stronger immune response, local and systemic side effects, but not necessarily protection.     

Numerical Analysis of the Taxonomy of Nocardiae and Rhodococci

The genera Nocardia and Rhodococcus were clearly differentiated in the present study. Eleven characteristics were shown to be useful for differentiation between these two genera. Nocardia asteroides sunsu stricto previously defined by Tsukamura was divided into two taxa. One contained the type strain and was considered to retain the name Nocardia asteroides in a new sense. Another was named in the present study as Nocardia nova sp. nov. Tsukamura. The type strain of this species is ATCC 33726. The following seven characters were useful for differentiating N. nova from newly defined N. asteroides: 1) arylsulfatase activity after 14 days; 2) catalase activity (semiquantitative); 3) β-esterase activity; 4) pyrazinamidase activity; 5) utilization of citrate as a sole source of carbon; 6) utilization of 2,3-butylene glycol as a sole carbon source; and 7) resistance to 5-fluorouracil (20 μg/ml). The name Nocardia farcinica for Tsukamura's Kyoto-I group should be rejected. This taxon has been named Nocardia paratuberculosis sp. nov. Tsukamura. The type strain is ATCC 23826. Three new species of the genus Rhodococcus were proposed: Rhodococcus aichiensis sp. nov. Tsukamura (type strain, ATCC 33611); Rhodococcus chubuensis sp. nov. Tsukamura (type strain, ATCC 33609); Rhodococcus obuensis sp. nov. Tsukamura (type strain, ATCC 33610).     

IgM but not IgG monoclonal anti-Nocardia brasiliensis antibodies confer protection against experimental actinomycetoma in BALB/c mice

Nocardia brasiliensis is a facultative intracellular microorganism that produces a human chronic infection known as actinomycetoma. Human and mouse anti- N. brasiliensis antibody response identify P24, P26 and P61 immunodominant antigens. In this work, we generated immunoglobulin M (IgM) and IgG monoclonal antibodies (mAbs) specific to immunodominant P61 antigen. The monoclonal IgM (NbM1) and IgG2a (NbG1) antibodies were assessed for their in vitro bactericidal activity, in vivo protective effect and ability to block catalase activity. These mAbs specifically recognized P61, but they did not inhibit its enzyme activity. The in vitro bactericidal effect of NbG1 was higher than the killing ability of the IgM mAb. In vivo experiments with a murine model of experimental infection with N. brasiliensis injected into rear footpads was used to test the effect of NbM1 and NbG1. The negative untreated group developed a chronic actinomycetoma within 4 weeks. IgM mAbs conferred protection to BALB/c mice infected with N. brasiliensis . IgG mAb lacked this protective effect. IgM mAb showed a dose–response correlation between antibody concentration and lesion size. These results demonstrate that humoral immune response mediated by antigen-specific IgM antibody protects against an intracellular bacterial infection.