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FEMS Microbiology Reviews Jul 2012Streptomyces bacteria are ubiquitous in soil, conferring the characteristic earthy smell, and they have an important ecological role in the turnover of organic material.... (Review)
Review
Streptomyces bacteria are ubiquitous in soil, conferring the characteristic earthy smell, and they have an important ecological role in the turnover of organic material. More recently, a new picture has begun to emerge in which streptomycetes are not in all cases simply free-living soil bacteria but have also evolved to live in symbiosis with plants, fungi and animals. Furthermore, much of the chemical diversity of secondary metabolites produced by Streptomyces species has most likely evolved as a direct result of their interactions with other organisms. Here we review what is currently known about the role of streptomycetes as symbionts with fungi, plants and animals. These interactions can be parasitic, as is the case for scab-causing streptomycetes, which infect plants, and the Streptomyces species Streptomyces somaliensis and Streptomyces sudanensis that infect humans. However, in most cases they are beneficial and growth promoting, as is the case with many insects, plants and marine animals that use streptomycete-produced antibiotics to protect themselves against infection. This is an exciting and newly emerging field of research that will become increasingly important as the search for new antibiotics switches to unusual and under-explored environments.
Topics: Animals; Fungi; Plant Diseases; Plant Physiological Phenomena; Plants; Streptomyces; Symbiosis
PubMed: 22091965
DOI: 10.1111/j.1574-6976.2011.00313.x -
Journal of Natural Products Apr 2018Sesterterpenes are usually found in plants and fungi, but are rare in bacteria. Here, we present the identification of StsC from Streptomyces somaliensis, a member of...
Sesterterpenes are usually found in plants and fungi, but are rare in bacteria. Here, we present the identification of StsC from Streptomyces somaliensis, a member of the UbiA superfamily, as a membrane-bound sesterterpene cyclase in bacteria. The cyclized products for StsC, somaliensenes A (1) and B (2), were identified by expressing the corresponding gene in an engineered Escherichia coli strain. The structures of 1 and 2 were determined by analysis of the NMR and MS spectroscopic data.
Topics: Cyclization; Escherichia coli; Magnetic Resonance Spectroscopy; Membranes; Sesterterpenes; Streptomyces
PubMed: 29553734
DOI: 10.1021/acs.jnatprod.7b01033 -
Bioorganic Chemistry Aug 2020With a combined strategy of bioinformatics analysis, gene manipulation coupled with variation of growth conditions, the targeted activation of polycyclic tetramate...
With a combined strategy of bioinformatics analysis, gene manipulation coupled with variation of growth conditions, the targeted activation of polycyclic tetramate macrolactams (PTMs) in the deepsea-derived Streptomyces somaliensis SCSIO ZH66 was conducted, which afforded a new (1) PTM, named somamycin A, along with three enol-type tetramic acid tautomers (2-4, somamycins B-D) of 10-epi-hydroxymaltophilin, 10-epi-maltophilin and 10-epi-HSAF, respectively. The structures of compounds 1-4 were elucidated by extensive spectroscopic analyses together with ECD calculations. Compound 1 exhibited notable growth inhibition against plant pathogenic fungi Fusariumoxysporum MHKW and Alternariabrassicae BCHB with the MIC values of 1.6 and 3.1 μg/mL, respectively, which were more potent than those of the positive control nystatin; and compounds 3 and 4 displayed moderate antifungal activities. Moreover, compounds 1-4 exhibited moderate cytotoxicity against the human cancer cell lines of HCT116 and K562.
Topics: Lactams; Polycyclic Compounds; Seawater; Spectrum Analysis; Streptomyces
PubMed: 32506015
DOI: 10.1016/j.bioorg.2020.103954 -
Archives of Dermatology Oct 1986
Topics: Actinomycetales Infections; Humans; Mycetoma
PubMed: 3767393
DOI: No ID Found -
Clinical and Experimental Dermatology Mar 2019Mycetoma caused by either filamentous fungi (eumycotic) or bacteria (actinomycotic) has recently been recognized by the World Health Organization as a neglected tropical... (Review)
Review
Mycetoma caused by either filamentous fungi (eumycotic) or bacteria (actinomycotic) has recently been recognized by the World Health Organization as a neglected tropical disease. Although mycetoma is preventable and treatable, especially in the early stages, it carries high morbidity and a huge socioeconomic burden. Skin and subcutaneous tissue is affected, with a classic presentation of hard woody swellings, discharging sinuses and presence of grains (containing the causative organism). Variants with swelling without sinuses have also been described. Left untreated it may involve underlying bone and muscle, leading to permanent disability. Common actinomycotic species include Streptomyces somaliensis, Actinomadura madurae, Actinomadura pelletieri, Nocardia brasiliensis and Nocardia asteroides, while Madurella mycetomatis, Madurella grisea, Pseudoallescheria boydii and Leptosphaeria senegalensis are common eumycotic agents. Men are more commonly affected than women, and the leg is the most frequently affected site. Diagnosis in suspected lesions is made with the help of grain examination, microscopy, imaging (radiography, ultrasonography, magnetic resonance imaging) and culture, and more recently by molecular methods such as PCR and molecular sequencing. Molecular sequencing for both fungi and bacteria is important for rapid and correct diagnosis, especially in culture-negative cases. Treatment is long, more successful in actinomycetoma than eumycetoma, and may require a holistic approach comprising antimicrobials, surgery and rehabilitation. Mycetoma can be prevented by simple measures such as wearing protective garments and shoes, especially in rural areas and during outdoor activities.
Topics: Actinomyces; Anti-Bacterial Agents; Antifungal Agents; Humans; Mycetoma; Skin
PubMed: 29808607
DOI: 10.1111/ced.13642 -
International Journal of Systematic and... Oct 2022A urease-producing Gram-stain-positive actinobacterium, designated strain T5, was isolated from a soil sample collected at a highway hillslope in Selangor, Malaysia. The...
A urease-producing Gram-stain-positive actinobacterium, designated strain T5, was isolated from a soil sample collected at a highway hillslope in Selangor, Malaysia. The strain was found to produce pale yellowish-pink aerial mycelia with smooth long chain spores and extensively branched light yellowish-pink substrate mycelia on oatmeal agar. Strain T5 grew at 15-37 °C, pH 6-11, and tolerated up to 9 % (w/v) NaCl, with optimal growth occurring at 28 °C, pH 6-9 and without NaCl. The whole-cell sugar hydrolysate of strain T5 contained galactose, glucose and ribose. The ll-diaminopimelic acid isomer was detected in the cell wall. Diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol were found to be the predominant polar lipids. The main fatty acids were anteiso-C, iso-C, anteiso-C and iso-C. Comparative analysis of the 16S rRNA gene sequences indicated that strain T5 belonged to of the family with the highest 16S rRNA gene sequence similarity to LCR6-01 (99.0 %). The overall genome relatedness indices revealed that the closest related species was LCR6-01 with 89.4 % average nucleotide identity and 33.7 % digital DNA-DNA hybridization. Phylogeny analyses showed that strain T5 was closely related to , , , and . Based on these polyphasic data, strain T5 represents a novel species, for which the name sp. nov. is proposed. The type strain is T5 (=TBRC 5137= DSM 42166).
Topics: RNA, Ribosomal, 16S; Phosphatidylethanolamines; Phylogeny; Diaminopimelic Acid; Soil; Galactose; Ribose; Cardiolipins; Sodium Chloride; Agar; Urease; Malaysia; Base Composition; Fatty Acids; DNA, Bacterial; Bacterial Typing Techniques; Phospholipids; Sequence Analysis, DNA; Streptomyces; Glucose; Phosphatidylcholines; Phosphatidylinositols; Nucleotides
PubMed: 36282570
DOI: 10.1099/ijsem.0.005594 -
Microbial Cell Factories May 2015Marine microorganisms are an important source of new drug leads. However, the discovery and sustainable production of these compounds are often hampered due to the...
Activation and enhancement of Fredericamycin A production in deepsea-derived Streptomyces somaliensis SCSIO ZH66 by using ribosome engineering and response surface methodology.
BACKGROUND
Marine microorganisms are an important source of new drug leads. However, the discovery and sustainable production of these compounds are often hampered due to the unavailable expression of cryptic biosynthetic gene clusters or limited titer. Ribosome engineering and response surface methodology (RSM) integrated strategy was developed in this study to activate cryptic gene cluster in the deepsea-derived Streptomyces somaliensis SCSIO ZH66, and subsequently isolation, structural analysis, and the yield enhancement of the activated compound, anticancer drug lead Fredericamycin A (FDM A), were performed.
RESULTS
In order to discover novel natural products from marine Streptomyces strains by genome mining strategy, the deepsea-derived S. somaliensis SCSIO ZH66 was subject to ribosome engineering to activate the expression of cryptic gene clusters. A resistant strain ZH66-RIF1 was thereby obtained with 300 μg/mL rifampicin, which accumulated a brown pigment with cytotoxicity on MS plate while absent in the wild type strain. After screening of fermentation conditions, the compound with pigment was purified and identified to be FDM A, indicating that the activation of a cryptic FDM A biosynthetic gene cluster was taken place in strain ZH66-RIF1, and then it was identified to be ascribed to the mutation of R444H in the β subunit of RNA polymerase. To further improve the yield efficiently, nine fermentation medium components were examined for their significance on FDM A production by Plackett-Burman design and Box-Behnken design. The optimum medium composition was achieved by RSM strategy, under which the titer of FDM A reached 679.5 ± 15.8 mg/L after 7 days of fermentation, representing a 3-fold increase compared to the original medium. In terms of short fermentation time and low-cost fermentation medium, strain ZH66-RIF1 would be an ideal alternative source for FDM A production.
CONCLUSIONS
Our results would hasten the efforts for further development of FDM A as a drug candidate. Moreover, this ribosome engineering and RSM integrated methodology is effective, fast and efficient; it would be applicable to genome mining for novel natural products from other strains.
Topics: Genetic Engineering; Isoquinolines; Molecular Sequence Data; Multigene Family; Mutation; Spiro Compounds; Streptomyces
PubMed: 25927229
DOI: 10.1186/s12934-015-0244-2 -
Medical Mycology 1998The recent emergence of invasive infections due to Nocardia spp., including nosocomial outbreak, is now evident. Newer molecular diagnostic and typing methods are... (Review)
Review
The recent emergence of invasive infections due to Nocardia spp., including nosocomial outbreak, is now evident. Newer molecular diagnostic and typing methods are developed. Although sulfonamide-based therapy is generally effective, optimal treatment may be guided by antimicrobial susceptibility testing of isolates. The improved classification of nocardiae and other related genera such as actinomadurae, using the 16S ribosomal RNA sequencing, provide a sound basis for improved diagnostic methods for the identification of members of clinically significant species. The commonest cause of eumycetoma in Sudan is Madurella mycetomatis, and Streptomyces somaliensis and Actinomadura madurae for actinomycetoma. The humoral immunity response in actinomycetoma patients and in experimental mice was measured and significant titre of anti-P24 antibody was demonstrated.
Topics: Actinomycetales; Animals; Bacterial Typing Techniques; Humans; Mice; Mycetoma; Nocardia; Nocardia Infections; Sudan
PubMed: 9988489
DOI: No ID Found -
Journal of Bacteriology Jul 2012We report the draft genome sequence of the human pathogen Streptomyces somaliensis (DSM 40738), a pathogen within a genus of largely saprophytic organisms. S....
We report the draft genome sequence of the human pathogen Streptomyces somaliensis (DSM 40738), a pathogen within a genus of largely saprophytic organisms. S. somaliensis causes severe and debilitating deep tissue and bone infections. The genome sequence is deposited in DDBJ/EMBL/GenBank with the accession number AJJM01000000.
Topics: Actinomycetales Infections; Foot Diseases; Genome, Bacterial; Humans; Male; Molecular Sequence Data; Mycetoma; Sequence Analysis, DNA; Streptomyces; Young Adult
PubMed: 22689234
DOI: 10.1128/JB.00534-12 -
The American Journal of Tropical... Jul 1987This study compares the in vitro ultrastructure of Streptomyces somaliensis with the grain formation seen in vivo. Cultured forms were cocco-bacillary with thick cell... (Comparative Study)
Comparative Study
This study compares the in vitro ultrastructure of Streptomyces somaliensis with the grain formation seen in vivo. Cultured forms were cocco-bacillary with thick cell walls and septa. Individual cells stained with PAS.TCH and Alcian blue. Grains were largely composed of an electron-dense fibrillar matrix surrounding clear areas, some of which contained organisms. The ultrastructural appearances of the latter were not significantly different from those seen in vitro although the cell wall was less well defined and did not stain with Alcian blue, and there were more intracellular lipid droplets. Host cells surrounding the mass were incorporated into the structure of the grain, a process associated with cell death. The grains of S. somaliensis appear to be derived from both host and actinomycete elements. Compared to other mycetoma agents the mechanism of grain formation by this organism is distinctive.
Topics: Cell Wall; Cytoplasm; Humans; Macrophages; Microscopy, Electron; Mycetoma; Streptomyces
PubMed: 3605500
DOI: 10.4269/ajtmh.1987.37.174