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Nocardia gypsoides, a species characterised by its ability to produce calcium sulphate granules, has been isolated for the first time from a corneal ulcer. In vivo this pseudomycete also forms gypsum. Every effort should be made to identify Actinomycetales to species level. The names Leptothrix and Streptothrix should be abandoned.
Selected ion monitoring was used to detect tuberculostearic acid (10-methyloctadecanoic acid) in sputum from patients with pulmonary tuberculosis. The specimens were autoclaved, lyophilized, extracted, and methanolysed before being subjected to thin-layer chromatography and injected into the gas chromatograph/mass spectrometer. Tuberculostearic acid could be detected in five of six tuberculous sputum specimens containing acid-fast rods detectable by light microscopy of Ziehl-Neelsen stained smears. After the sputum specimens had been cultured for five days on Löwenstein-Jensen medium, when still no colonies could be observed visually, the presence of tuberculostearic acid was demonstrated in all six cases of tuberculosis. In corresponding analyses of sputum from eight patients with non-tuberculous pneumonia, tuberculostearic acid was not found. This fatty acid, the presence of which was also demonstrated in cultures of various mycobacterial and nocardial species, is characteristic of organisms of the order Actinomycetales. The demonstration of tuberculostearic acid in sputum specimens may constitute a rapid and sensitive way of diagnosing pulmonary tuberculosis.
BACKGROUND: Despite great advances in clarifying the family tree of life, it is still not agreed where its root is or what properties the most ancient cells possessed--the most difficult problems in phylogeny. Protein paralogue trees can theoretically place the root, but are contradictory because of tree-reconstruction artefacts or poor resolution; ribosome-related and DNA-handling enzymes suggested one between neomura (eukaryotes plus archaebacteria) and eubacteria, whereas metabolic enzymes often place it within eubacteria but in contradictory places. Palaeontology shows that eubacteria are much more ancient than eukaryotes, and, together with phylogenetic evidence that archaebacteria are sisters not ancestral to eukaryotes, implies that the root is not within the neomura. Transition analysis, involving comparative/developmental and selective arguments, can polarize major transitions and thereby systematically exclude the root from major clades possessing derived characters and thus locate it; previously the 20 shared neomuran characters were thus argued to be derived, but whether the root was within eubacteria or between them and archaebacteria remained controversial. RESULTS: I analyze 13 major transitions within eubacteria, showing how they can all be congruently polarized. I infer the first fully resolved prokaryote tree, with a basal stem comprising the new infrakingdom Glidobacteria (Chlorobacteria, Hadobacteria, Cyanobacteria), which is entirely non-flagellate and probably ancestrally had gliding motility, and two derived branches (Gracilicutes and Unibacteria/Eurybacteria) that diverged immediately following the origin of flagella. Proteasome evolution shows that the universal root is outside a clade comprising neomura and Actinomycetales (proteates), and thus lies within other eubacteria, contrary to a widespread assumption that it is between eubacteria and neomura. Cell wall and flagellar evolution independently locate the root outside Posibacteria (Actinobacteria and Endobacteria), and thus among negibacteria with two membranes. Posibacteria are derived from Eurybacteria and ancestral to neomura. RNA polymerase and other insertions strongly favour the monophyly of Gracilicutes (Proteobacteria, Planctobacteria, Sphingobacteria, Spirochaetes). Evolution of the negibacterial outer membrane places the root within Eobacteria (Hadobacteria and Chlorobacteria, both primitively without lipopolysaccharide): as all phyla possessing the outer membrane beta-barrel protein Omp85 are highly probably derived, the root lies between them and Chlorobacteria, the only negibacteria without Omp85, or possibly within Chlorobacteria. CONCLUSION: Chlorobacteria are probably the oldest and Archaebacteria the youngest bacteria, with Posibacteria of intermediate age, requiring radical reassessment of dominant views of bacterial evolution. The last ancestor of all life was a eubacterium with acyl-ester membrane lipids, large genome, murein peptidoglycan walls, and fully developed eubacterial molecular biology and cell division. It was a non-flagellate negibacterium with two membranes, probably a photosynthetic green non-sulphur bacterium with relatively primitive secretory machinery, not a heterotrophic posibacterium with one membrane.
The enzymes of the terminal steps of the phenylalanine and tyrosine biosynthesis were partially purified and characterized in Microtetraspora glauca, a spore-forming member of the order Actinomycetales. This bacterium relies exclusively on the phenylpyruvate route for phenylalanine synthesis, no arogenate dehydratase activity being found. Prephenate dehydratase is subject to feedback inhibition by phenylalanine, tyrosine and tryptophan, each acting as competitive inhibitor by increasing the Km of 72 microM for prephenate. Based on the results of gel chromatography on Sephadex G-200, the molecular mass of about 110,000 Da is not altered by any of the effectors. The enzyme is quite sensitive to inhibition by 4-hydroxymercuribenzoate. Microtetraspora glauca can utilize arogenate and 4-hydroxyphenylpyruvate as intermediates in tyrosine biosynthesis. Prephenate and arogenate dehydrogenase activities copurifying from ion exchange columns with coincident profiles were detected. From gel-filtration columns the two activities eluted at an identical molecular-mass position of about 68,000 Da. The existence of a single protein exhibiting substrate ambiguity is consistent with the findings, that both dehydrogenases have similar chromatographic properties, exhibit cofactor requirement for NAD and are inhibited to the same extent by tyrosine and 4-hydroxymercuribenzoate.
Confluent and reticulated papillomatosis (CARP) was first described >60 years ago. It is distinct from acanthosis nigricans. This article presents the results of a review of the literature in MEDLINE through May 2006 using the terms 'confluent and reticulated papillomatosis', 'reticulated and confluent papillomatosis of Gougerot and Carteaud', and 'reticulated papillomatosis'. A recent report has linked the presence of Dietzia spp. (family: Dietziaceae; suborder: Corynebacterineae; order: Actinomycetales) in the skin to CARP. CARP has also been linked to defects in keratinization. Other possible causes of CARP that have been suggested but seem less likely include endocrine abnormalities, Pityrosporum, a reaction to UV light, and a variation of cutaneous amyloidosis. CARP has been reported worldwide and occurs in both sexes, all age groups, and all races. The disorder can initially manifest as hyperkeratotic or verrucous papules that coalesce to form a reticular pattern peripherally and confluent plaques centrally. Although a variety of treatments for CARP exist, oral minocycline 50-100mg twice daily has been the preferred treatment. However, recent reports of the effectiveness of azithromycin 250-500mg three times weekly may make azithromycin the preferred treatment for CARP, since it has a more benign adverse effect profile than minocycline. Other effective antibacterial treatments include fusidic acid 1000mg daily, clarithromycin 500mg daily, erythromycin 1000mg daily, tetracycline 500mg twice daily, and cefdinir 300mg twice daily. If a recent finding that CARP is caused by a bacterial microorganism is replicated, treatment should likely be determined by bacterial sensitivities, antibacterial adverse effect profiles, and cost considerations. Other oral treatments of CARP that are effective but currently disfavored because of the effectiveness of minocycline include isotretinoin, acitretin, and etretinate. There have been mixed reports regarding the effectiveness of topical treatments, which include selenium sulfide, ketoconazole cream, tretinoin, tazarotene, tacalcitol, and calcipotriene (calcipotriol).
Rifamycins are primarily produced by Gram-positive bacterium Amycolatopsis mediterranei, which belongs to the order Actinomycetales. These antibiotics, apart from their application against pathogens of tuberculosis and leprosy, have also been found to be effective against several other pathogens including Mycobacterium avium and Pneumococcus. Because of the importance of rifamycin, the producer strain A. mediterranei has been genetically manipulated since 1957 in order to develop a strain that can either produce larger amounts of rifamycin or derivatives of rifamycin. In this article, the importance of the producer strain, traditional methods (mutations and recombination) of strain improvement, their limitations, and the development of a cloning vector and transformation methods that have made recombinant DNA techniques accessible for genetic manipulations of A mediterranei are discussed.
Two new aminoglycoside antibiotics, sporaricins A (C17H35N5O5) and B (C15H32N4O4) produced by a rare actinomycetales, Saccharopolyspora hirsuta subsp. kobensis have been isolated by column chromatography on a cation-exchange resin. Sporaricin A is highly active against Gram-positive and Gram-negative bacteria including aminoglycoside-resistant strains.
A new antifungal antibiotic, CB-25-I, was isolated from the culture broth of a strain of Serratia plymuthica. The antibiotic, a water-soluble dipeptide, is structurally related to Sch 37137 and A 19009, both produced by strains of Actinomycetales. The antibiotic exhibits inhibitory activity against Candida albicans in YNB medium (a synthetic medium), but the activity is significantly reduced in Sabouroud dextrose medium.
The nocardiosis is an infection caused by a bacterial pathogen agent, Nocardia, belonging to the Actinomycetales order. They are Gram-positive, strictly aerobic bacteria. Members of the genus Nocardia are ubiquitous. They are frequently isolated from soil, water, air dusts. The mode of contamination occurs by inhalation or by cutaneous or ocular traumatic lesion. Clinically, nocardiosis is essentially characterized by pulmonary diseases. Others secondary localizations are described, such as in the central nervous system. Nocardia can be responsible for important cutaneous, subcutaneous and lymphocutaneous manifestations. In the same way, some extrapulmonary diseases and spread nocardiosis are more rarely observed. Several factors seem to favour the development of Nocardia. The immunocompromised patients, particularly those with organ transplant and the patients treated with immunosuppressor treatments, offer strong predispositions to this opportunistic disease. The nocardiosis is nevertheless observed in healthy persons. In front of polymorphic and specific-less clinical manifestations, large phenotypic heterogeneity, and resistance profiles to specific antibiotics, a correct diagnosis for Nocardia species is necessary to apply an adequate treatment. The techniques of identification based on the chemotaxonomic analysis and the susceptibility to different inhibitors are efficient for the identification of genus and species. However, because of the slow growth rate of Nocardia, the reading of these tests can require several weeks of incubation. With the intention of the rapid identification of genus and species, the molecular techniques (PCR-RFLP) seem to be efficient. The technique of RAPD allows an efficient molecular typing, which will give a better knowledge concerning transmission, ecological niches and epidemic reservoirs.
The active stalactites from Grotta dei Cervi, Porto Badisco, southeastern Italy, were sampled to investigate the microbial communities present in these speleothems. Sampling was carried out in a transect about 150 m long in the central gallery, where numerous Gram-positive bacteria were isolated. Actinomycetes of the genus Streptomyces were the most abundant, followed by members of the genus Bacillus. Further isolates were assigned to the genera Amycolatopsis, Arthrobacter; Agromyces. Micrococcus, Nocardiopsis and Rhodococcus of the order Actinomycetales. The ability of actinomycetes to colonize subterranean environments is discussed.
Mycobacterium leprae multiplied in media enriched with substances originating from other mycobacteria, from non-acid-fast Actinomycetales or from gram-positive or gram-negative Eubacteriales. Most of the M. leprae strains did not grow on a synthetic medium containing the amino acids present in M. smegmatis, but the growth-promoting effect of sonic extracts of this organism indicated that substances of bacterial origin, other than amino acids, do act as growth factors. The identification of the growing, acid-fast microorganisms with M. leprae was verified by their ability to oxidize D-3,4-dihydroxyphenylalanine (D-dopa test). M. leprae did not multiply on Nakamura medium unless at least 40% of medium NM7 enriched by bacterial substances was present. Adequate aeration was essential for multiplication of M. leprae in enriched NM7 and No. 3 media.
Almost all of the investigated samples of the Arctic and Antarctic permafrost sediments of different genesis with ages from 5-10 thousand to 2-3 million years were found to contain viable micromycete and bacterial cells. The maximum amounts of viable cells of fungi (up to 10(4) CFU/g air-dried sample) and bacteria (up to 10(7)-10(9) CFU/g air-dried sample) were present in fine peaty sediment samples taken from different depths. The identified micromycetes belonged to more than 20 genera of the divisions Basidiomycota, Ascomycota, and Zygomycota, and some represented mitosporic fungi. Thawing the samples at 35 and 52 degrees C allowed the number of detected fungal genera to be increased by more than 30%. Aerobic heterotrophic prokaryotes were dominated by coryneform, nocardioform, and spore-forming microorganisms of the order Actinomycetales. Analysis of the isolated fungi and actinomycetes showed that most of them originated from the microbial communities of ancient terrestrial biocenoses.
14 strains of Actinomycetes were isolated from soil samples collected in Yunnan, China. Experiments showed that they had activity of herbicide. In this paper, the morphological and chemotaxonomic characters of these strains were studied and they were identified as three genera of Actinomycetales respecitively, such as Streptomyces, Micromonospora and Nocardia.
There are different categories of non-infectious antigenic contaminants capable of provoking pulmonary reactions: thermophilic actinomycetales, fungi, vegetable particles, protein antigens, arthropods, drugs; their identification is based on their isolation, culture, and the study of their biochemical composition. The pulmonary reactions depend on the size and number of antigenic particles inhaled and by the underlying background. The immunological mechanisms brought into play a complex Arthus's phenomenon: in addition to the IgGs, the IgEs and the different factors of complement intervene; the recent acquisitions of immunomorphology enable better comprehension of the histogenesis of the pulmonary granuloma. The diagnosis of extrinsic allergic alveolitis is founded on well defined criteria of clinical, radiological, respiratory functional, immunological and histophthological order. These conditions are met with in agricultural, industrial and urban environments or are related to iatrogenic diseases. Many problems still remain obscure with regards to the pathogenesis and integration within the framework of immunological pneumonia of various conditions, and especially certain sarcoidosis.
This research is a continuation of the series of studies of the parietal microbiota of the bowel tissue samplings by the gas chromatography and mass spectrometry (GCMS) method [G.A. Ossipov et al.//Journal of the Society of Russian Gastroenterologists, 2001, 1:54-69]. The purpose was to study a number of new microorganisms in view of new data on the composition of their fatty acids (FA) and aldehydes; to confirm the presence of a number of bacteria, fungi and aerobic actinomycetes revealed earlier by FA markers in the composition of the bowel parietal microbiota by their isolation in a pure culture; to amend the estimation of the clinical value of changes in the composition of the human bowel parietal microflora in case of irritable bowel syndrome (IBS) and antibiotics-associated diarrhea (AAD). We examined 31 patients with IBS with predominating diarrhea, 18 patients with AAD and 3 volunteers (a control group). We studied the blood samples, tissue samplings of the mucous coat of the jejunum, ileum and colon and composition of healthy people's feces. The GCMS method was applied. Morphology of defined strains was controlled by methods of light and scanning electron microscopy. We found a substantial portion of eubacteria among the bowel microorganisms and specific changes of their species in case of IBS and AAD. Taking into account their physiological and biochemical activity, when regulating their concentration one can expect at least the same effect as when regulating the number of bifidobacteria and lactobacilli in treatment of intestinal pathologies and other diseases related to bowel dysbacteriosis. The analysis of the feces microbiota using the GCMS method by FA of parietal microorganisms provides reliable data on their number both in feces and in tissue samplings. We found a substantial portion of eubacteria among other bowel microorganisms (27% in the jejunum and 16% in the colon) and specific changes of their species in case of IBS and AAD. The concentration of streptomycetes, rhodococci and other members of the Actinomycetales order becomes dozens times more and/or reduces in pathological states. The tenfold concentration of markers of lactobacilli and bifidobacteria in some diseases stimulates the differentiated application of widespread probiotics based on these bacteria.
The investigation of microbiological rate of indoor air pollution on Faculty of Building and Environmental Engineering at Białystok University of Technology were made by sedimentation method in accordance with Polish standards (PN-89/Z-04111/01,02,03). Six series of measurements were carried out from autumn 2002 to spring 2003. The results show bad microbiological quality of indoor air on Faculty of Building and Environmental Engineering at Białystok University of Technology. It was found that the number of Staphylococcus, Actinomycetales as well as the total count of bacteria were too high and broke the Polish regulations of the clear air. Because of the students' and other workers' safety, monitoring of microbiological pollution of the indoor air must be done and existing emergency to improve the quality of the air must be lead.
Streptomycetes are Gram-positive, soil-inhabiting bacteria of Actinomycetales. These organisms exhibit complex life cycle and secondary metabolic pathways, and produce many economically important secondary metabolites. This review presented recent progress in Streptomycetes chromosome structure,genomics and the research of secondary metabolic pathway in Streptomyces. As more genomic sequences become available, it wiil be greatly facilitated to elucidate metabolic and regulatory networks and gain the over-production of desired metabolites or create the novel production of commercially important compounds.
Morphological, cultural and chemotaxonomic properties of 12 gram-positive soil cultures isolated were studied by using a test system developed for screening the organisms producing broad-spectrum antibiotics among Nocardiaforms (Coryneforms). The cultures were found to belong to Actinomycetales, Nocardioforms, Mycobacteriaceae and Mycobacterium. The saprophytic rapidly growing soil mycobacteria showed antibiotic activity against a large number of gram-positive and gram-negative test microbes including those belonging to Pseudomonas and Proteus resistant to the majority of the antibiotics currently used in medicine.