Strains Of Actinomyces Research Articles

Brevibacterium litoralis sp. nov., a cellulose-degrading strain isolated from marine surface sediment.

A Gram stain-positive, non-spore-forming, non-motile, short-rod actinomyces strain GXQ1321T was isolated from maritime surface sediments in Beihai (21° 41' 21.65″ N, 109° 05' 76.56″ E), Guangxi Zhuang Autonomous Region, and a number of categorization studies were performed. Following a period of 72h of incubation at a temperature of 30°C within a modified actinomycete culture medium, the colony was light-yellow, circular, smooth, central bulge, convex, opaque, with a 1.2-2.3mm diameter. Strain GXQ1321T had the ability to degrade cellulose. Chemotaxonomic studies revealed that the major methylnaphthoquinones in strain GXQ1321T was MK-8(H2). The most prevalent cellular fatty acids were anteiso-C19:0, anteiso-C15:0, anteiso-C17:0, and iso-C16:0. The whole-cell sugars of the strain GXQ1321T were identified rhamnose, xylose and glucose. Meso-diaminopimelic acid was found in the peptidoglycan hydrolysate, and the polar lipids were identified as diphosphatidylglycerol, three phosphoglycolipid, phosphatidylglycerol and two unknown glycolipid. This strain had 69.6% DNA G+C content. Strain GXQ1321T is classified as Brevibacterium based on its 16S rRNA gene sequence. It is closely related to Brevibacterium samyangense SST-8T (96.8%) and Brevibacterium rongguiense 5221T (96.3%). The average nucleotide identity (ANI) values of GXQ1321T and the above two type strains were 73.9-77.1%, and the digital DNA-DNA hybridisation (dDDH) values were 15.3-21.1%. Based on the phylogenetic, chemotaxonomic and physiological data, strain GXQ1321T was considered to be a novel species of the genus Brevibacterium, named Brevibacterium litoralis sp. nov, with the type strain GXQ1321T (= MCCC 1K08964T = KCTC 59167T).

Genome characterization and taxonomy of Actinomyces acetigenes sp. nov., and Actinomyces stomatis sp. nov., previously isolated from the human oral cavity

BackgroundActinomyces strains are commonly found as part of the normal microflora on human tissue surfaces, including the oropharynx, gastrointestinal tract, and female genital tract. Understanding the diversity and characterization of Actinomyces species is crucial for human health, as they play an important role in dental plaque formation and biofilm-related infections. Two Actinomyces strains ATCC 49340 T and ATCC 51655 T have been utilized in various studies, but their accurate species classification and description remain unresolved.ResultsTo investigate the genomic properties and taxonomic status of these strains, we employed both 16S rRNA Sanger sequencing and whole-genome sequencing using the Illumina HiSeq X Ten platform with PE151 (paired-end) sequencing. Our analyses revealed that the draft genome of Actinomyces acetigenes ATCC 49340 T was 3.27 Mbp with a 68.0% GC content, and Actinomyces stomatis ATCC 51655 T has a genome size of 3.08 Mbp with a 68.1% GC content. Multi-locus (atpA, rpoB, pgi, metG, gltA, gyrA, and core genome SNPs) sequence analysis supported the phylogenetic placement of strains ATCC 51655 T and ATCC 49340 T as independent lineages. Digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI), and average amino acid identity (AAI) analyses indicated that both strains represented novel Actinomyces species, with values below the threshold for species demarcation (70% dDDH, 95% ANI and AAI). Pangenome analysis identified 5,731 gene clusters with strains ATCC 49340 T and ATCC 51655 T possessing 1,515 and 1,518 unique gene clusters, respectively. Additionally, genomic islands (GIs) prediction uncovered 24 putative GIs in strain ATCC 49340 T and 16 in strain ATCC 51655 T, contributing to their genetic diversity and potential adaptive capabilities. Pathogenicity analysis highlighted the potential human pathogenicity risk associated with both strains, with several virulence-associated factors identified. CRISPR-Cas analysis exposed the presence of CRISPR and Cas genes in both strains, indicating these strains might evolve a robust defense mechanism against them.ConclusionThis study supports the classification of strains ATCC 49340 T and ATCC 51655 T as novel species within the Actinomyces, in which the name Actinomyces acetigenes sp. nov. (type strain ATCC 49340 T = VPI D163E-3 T = CCUG 34286 T = CCUG 35339 T) and Actinomyces stomatis sp. nov. (type strain ATCC 51655 T = PK606T = CCUG 33930 T) are proposed.

Antifungal Activity of Streptomyces hygroscopicus JY-22 against Alternaria alternata and Its Potential Application as a Biopesticide to Control Tobacco Brown Spot

Tobacco brown spot caused by Alternaria alternata is a devastating fungal disease endangering plant production. To effectively control brown spot disease, an antagonistic Actinomyces strain, Streptomyces hygroscopicus JY-22, was isolated from rhizospheric soil, which remarkably restrains the growth of phytopathogenic fungus Alternaria alternata. This antagonistic strain and its culture filtrate showed significant antifungal activity against Alternaria alternata. Firstly, the confrontation culture method of strains JY-22 and Alternaria alternata showed that Streptomyces hygroscopicus JY-22 had noticeable antifungal activity against Alternaria alternata, including inhibition of mycelial growth and mycelial morphological changes, compared with the control group. Furthermore, the culture filtrate of Streptomyces hygroscopicus JY-22 showed substantial inhibition of the mycelial growth and spore germination of Alternaria alternata in a dose-dependent manner. Additional studies revealed that these antifungal actions were mainly related to membrane-active mechanisms that increased membrane permeability and damaged the cell membrane, leading to changes in certain cytoplasmic properties, such as extracellular conductivity and ergosterol, MDA and soluble protein content. In detached-leaf and field experiments, foliar spraying with culture filtrate resulted in smaller lesions and a lower disease index than the control group. Taken together, these results suggest that Streptomyces hygroscopicus JY-22 and its culture filtrate have the potential to be a safe biopesticide for the bio-control of tobacco brown spot.

Genomic Diversity among Actinomyces naeslundii Strains and Closely Related Species

The aim of this study was to investigate and clarify the ambiguous taxonomy of Actinomyces naeslundii and its closely related species using state-of-the-art high-throughput sequencing techniques, and, furthermore, to determine whether sub-clusters identified within Actinomyces oris and Actinomyces naeslundii in a previous study by multi locus sequence typing (MLST) using concatenation of seven housekeeping genes should either be classified as subspecies or distinct species. The strains in this study were broadly classified under Actinomyces naeslundii group as A. naeslundii genospecies I and genospecies II. Based on MLST data analysis, these were further classified as A. oris and A. naeslundii. The whole genome sequencing of selected strains of A. oris (n = 17) and A. naeslundii (n = 19) was carried out using Illumina Genome Analyzer IIxe and Roche 454 allowing paired-end and single-reads sequencing, respectively. The sequences obtained were aligned using CLC Genomic workbench version 5.1 and annotated using RAST (Rapid Annotation using Subsystem Technology) release version 59 accessible online. Additionally, genomes of seven publicly available strains of Actinomyces (k20, MG1, c505, OT175, OT171, OT170, and A. johnsonii) were also included. Comparative genomic analysis (CGA) using Mauve, Progressive Mauve, gene-by-gene, Core, and Pan Genome, and finally Digital DNA-DNA homology (DDH) analysis was carried out. DDH values were obtained using in silico genome-genome comparison. Evolutionary analysis using ClonalFrame was also undertaken. The mutation and recombination events were compared using chi-square test among A. oris and A. naeslundii isolates (analysis methods are not included in the study). CGA results were consistent with previous traditional classification using MLST. It was found that strains of Actinomyces k20, MG1, c505, and OT175 clustered in A. oris group of isolates, while OT171, OT170, and A. johnsonii appeared as separate branches. Similar clustering to MLST was observed for other isolates. The mutation and recombination events were significantly higher in A. oris than A. naeslundii, highlighting the diversity of A. oris strains in the oral cavity. These findings suggest that A. oris forms six distinct groups, whereas A. naeslundii forms three. The correct designation of isolates will help in the identification of clinical Actinomyces isolates found in dental plaque. Easily accessible online genomic sequence data will also accelerate the investigation of the biochemical characterisation and pathogenesis of this important group of micro-organisms.

ВИХОДЕЦЬ ІЗ УКРАЇНИ ЗЕЛЬМАН АБРАХАМ ВАКСМАН — ВИДАТНИЙ ВЧЕНИЙ, НОБЕЛІВСЬКИЙ ЛАУРЕАТ, РОДОНАЧАЛЬНИК СТРЕПТОМІЦИНУ ТА СУЧАСНОЇ ЕРИ ПРОТИТУБЕРКУЛЬОЗНОЇ ХІМІОТЕРАПІЇ

Throughout its existence, humanity has experienced both evolution and progress in health matters and borne the burden of complex diseases and shortened life duration. Tuberculosis is an example of a pathology that until recently was a sentence for the patient. Every successful step in the search for tuberculosis treatment (which means saving a life) is priceless. The aim was to study of the biography of Selman Waksman and the history of the streptomycin discovery according to the literature data. Selman Waksman was born in 1888 in a Ukrainian village near Vinnitsa, and immigrated to the United States in 1910. He received a bachelor’s degree in 1915, and in 1916 — a magister degree in the agricultural course of Rutgers College. In 1918, Selman received Ph.D. in Biochemistry in the University of California. Since 1918, he worked in the Department of Soil Microbiology at Rutgers University and studied actinomycetes. In 1923, Waksman discovered that certain actinomycetes produced substances toxic to bacteria, and in 1939 he began an extensive research program to determine the nature of the substances by which various soil microbes destroyed each other. Actinomycin, an effective but toxic antibiotic, was isolated in 1940. In 1942, the antibiotic streptothricin was discovered and studied, a highly active against the M. tuberculosis, but too toxic. In 1943, together with graduate student Albert Schatz, two strains of Actinomyces were isolated, which produced a substance with antibiotic activity — streptomycin. Streptomycin had shown antibiotic activity against several bacteria, including M. tuberculosis. The drug was not toxic to animals. The great practical prospects of streptomycin for the treatment of tuberculosis and other infections led to the award of the Nobel Prize in Physiology or Medicine in 1952. Dr. Waksman introduced and popularized the term “antibiotic” in microbiology. He published more than 447 articles and wrote, independently or with co-authors, 28 books. When the Nobel Prize was awarded to the developer of streptomycin, a drug that saved thousands of human lives, the outstanding scientist was recognized as one of the greatest benefactors of mankind. Key words: Selman Abraham Waksman, streptomycin, tuberculosis, history of medicine.

A Culture Supernatant from an Actinomycete sp. Affects Biofilm Formation and Virulence Expression of Candida auris.

The multidrug-resistant pathogen Candida auris is characterized by its aggregation under certain conditions, which affects its biofilm formation, drug susceptibility, and pathogenicity. Although the innate tendency to aggregate depends on the strain, the mechanism regulating C. auris aggregation remains unclear. We found that the culture supernatant from one of the 95 Actinomyces strains isolated from a deep-sea environment (IMAs2016D-66) inhibited C. auris aggregation. The cells grown in the presence of IMAs2016D-66 exhibited reduced hydrophobicity, biofilm formation, and enhanced proteolytic activity. In addition, the efflux pump activity of the fluconazole-resistant C. auris strain LSEM 3673 was stimulated by IMAs2016D-66, whereas no significant change was observed in the fluconazole-susceptible strain LSEM 0643. As the relationship between aggregative tendency and virulence in C. auris is still unclear, IMAs2016D-66 can serve as a tool for investigating regulatory mechanisms of phenotype switching and virulence expression of C. auris. Understanding of phenotype switching may help us not only to understand the pathogenicity of C. auris, but also to design new drugs that target the molecules regulating virulence factors.

Streptomyces: Derived Active Extract Inhibits Candida albicans Biofilm Formation.

Candida albicans is an opportunistic pathogen that causes biofilm-associated infections. C. albicans biofilms are known to display reduced susceptibility to antimicrobials and high rates of acquired antibiotic resistance, and biofilm forming in C. albicans further hampers treatment options and highlights the need for new antibiofilm strategies. Identifying active components from desert actinomycetes strains to inhibit the formation of C. albicans biofilms represents an effective treatment strategy. In this study, actinomycetes that can inhibit C. albicans biofilm formation were isolated from the Taklimakan Desert, and the underlying mechanisms were explored. After screening the anti-C.albicans biofilm activities of culture supernatants from 170 Actinomycete strains, six strains showed significant inhibition of C. albicans biofilm formation. Microscopic examination showed a reduction in biofilm formation of C. albicans treated with supernatants from actinomycetes. Scanning electron microscopy showed that the morphological changes in biofilm cells were caused by cell membrane rupture and cell material leakage. Then, C.albicans biofilms were destroyed by changing the content of extracellular polysaccharides or degrading extracellular DNA. Finally, a preliminary study on active substances extracted from a new species (TRM43335) showed that the substances that inhibited the formation of biofilms might be peptides. This study provides preliminary evidence that desert actinomyces strains have inhibitory effects on the biofilm development of C. albicans.

Study of antibacterial activity of Streptomyces sp. SS473 isolated from plants against ESBL-producing Escherichia coli

The broad spectrum β-lactamase-producing E. coli(ESBL) is a dangerous bacterial pathogen in humans due to its resistance to many antibiotics. This is especially serious in the context of a limited number of new antibiotics for treating bacterial infections. This leads to a global public health threat and places an urgent need for new antibiotics. In this study, the authors investigated the antibacterial properties of an actinomyces strain isolated from the plant Clinacanthus nutans against the ESBL-producing E. coli strains. These actinomyces strains were designated as SS473. Moreover, SS473 showed a broad spectrum of antibacterial activity on several clinically isolated pathogenic bacteria. Culture media have different effects on the antibacterial activity of SS473. In stability tests, the antibacterial activity of strain SS473 remained at a temperature up to 80oC but was lost at pH 3 and 13. By contrast, the antibacterial activity was not affected by UV and protease treatments. Based on the results of morphological identification with specific media for Streptomyces and molecular identification on 16S rRNA gene, strain SS473 was suggested to belong to the Streptomyces genus and was named Streptomycessp. SS473. The results in this study will pave the way for the following research on the identification of secondary metabolites having antibacterial activity and their biosynthetic pathways in Streptomyces sp. SS473 in the future

Medium Optimization for Spore Production of a Straw-Cellulose Degrading Actinomyces Strain under Solid-State Fermentation Using Response Surface Method

The strains capable of degrading cellulose have attracted much interest because of their applications in straw resource utilization in solid-state fermentation (SSF). However, achieving high spore production in SSF is rarely reported. The production of spores from Streptomyces griseorubens JSD-1 was investigated in shaker-flask cultivation in this study. The optimal carbon, organic nitrogen and inorganic nitrogen sources were sucrose, yeast extract and urea, respectively. Plackett–Burman design (PBD) was adopted to determine the key medium components, and the concentration levels of three components (urea, NaCl, MgSO4·7H2O) were optimized with the steepest ascent path and central composite design (CCD), achieving 1.72 × 109 CFU/g of spore production. Under the optimal conditions (urea 2.718% w/v, NaCl 0.0697% w/v, MgSO4·7H2O 0.06956% w/v), the practical value of spore production was 1.69 × 109 CFU/g. The determination coefficient (R2) was 0.9498, which ensures an adequate credibility of the model.

The saccharibacterium TM7x elicits differential responses across its host range

Host range is a fundamental component of symbiotic interactions, yet it remains poorly characterized for the prevalent yet enigmatic subcategory of bacteria/bacteria symbioses. The recently characterized obligate bacterial epibiont Candidatus Nanosynbacter lyticus TM7x with its bacterial host Actinomyces odontolyticus XH001 offers an ideal system to study such a novel relationship. In this study, the host range of TM7x was investigated by coculturing TM7x with various related Actinomyces strains and characterizing their growth dynamics from initial infection through subsequent co-passages. Of the twenty-seven tested Actinomyces, thirteen strains, including XH001, could host TM7x, and further classified into “permissive” and “nonpermissive” based on their varying initial responses to TM7x. Ten permissive strains exhibited growth/crash/recovery phases following TM7x infection, with crash timing and extent dependent on initial TM7x dosage. Meanwhile, three nonpermissive strains hosted TM7x without a growth-crash phase despite high TM7x dosage. The physical association of TM7x with all hosts, including nonpermissive strains, was confirmed by microscopy. Comparative genomic analyses revealed distinguishing genomic features between permissive and nonpermissive hosts. Our results expand the concept of host range beyond a binary to a wider spectrum, and the varying susceptibility of Actinomyces strains to TM7x underscores how small genetic differences between hosts can underly divergent selective trajectories.

Aktywność olejku pichtowego (Oleum Pichtae) wobec bakterii beztlenowych

Introduction. Abies whitebark (Abies sibirica L.) belonging to the family Pinaceae. The tree grown in Mongol, China and Siberian taiga. Produced the pichtae oil, which is obtained by hydrodistillation method. It contain: α-pinene, β-pinene, β-caryophyllene, bornyl acetate, camphene, mircene and cineole. The oil exhibiting expectorant, analgesic, anti-inflammatory, antialergic, liver restorative, adaptogenic and antioxidant properties. It has antimicrobial activity. Aim. The aim of the date was to determine the susceptibility of anaerobic bacteria isolated from patients to pichtae oil. Material and methods. The investigated 49 strains of bacteria isolated from patients from genus Bacteroides (7 strains), Parabacteroides (1), Prevotella (8), Porphyromonas (5), Tannerella (1), Fusobacterium (6), Finegoldia (4), Parvimonas (2), Peptostreptococcus (4), Actinomyces (4), Bifidobacterium (1), Propionibacterium (6), and 10 reference strains. The concentrations the oil were the following: 2.5, 5.0, 7.5, 10.0, 15.0 and 20.0 mg/ml. The pichtae oil was added to Brucella agar with 5% defibrynated sheep blood, menadione and hemin. Inoculum containing 106 CFU/ml was seeded with Steers replicator upon the agar with oil or without oil (strains growth control). The incubation was carried out in anaerobic jars containing 10% C02 , 10% H2 and 80% N2 , palladic catalyst and anaerobic indicator, at 37°C for 48 hrs. The MIC was defined as the lowest concentration of the pichtae oil that completely inhibited growth the anaerobic bacteria. Results. The results investigation indicated that from Gram-negative rods Tannerella forsythia (MIC = 5.0 mg/ml), Bacteroides fragilis and Bacteroides uniformis (MIC = 7.5 mg/ml) were the most susceptible to pichtae oil. The growth of Prevotella strains were inhibited by concentrations in ranges 5.0-15.0 mg/ml. The Prevotella bivia (MIC 10.0-15.0 mg/ml) and Prevotella buccalis (MIC = 15.0 mg/ml) were the most resistant. The tested oil was active on account genus of Fusobacterium strains in concentrations 5.0-10.0 mg/ml. The Gram-positive cocci were the more sensitive then rods. The growth was inhibited by concentrations in ranges ≤ 2.5-10.0 mg/ml. The oil was equally effective against Gram-positive rods (MIC ≤ 2.5-10.0 mg/ml). From this bacteria the more susceptible were the strains of Actinomyces (MIC ≤ 2.5-7.5 mg/ml) and the least a rods from genus of Bifidobacterium (MIC = 10.0 mg/ml). The date indicated, that the Gram-positive anaerobes were the more susceptible to pichtae oil than Gram-negative rods. Conclusions. From among the Gram-negative bacteria the more susceptible to pichtae oil were the rods from genus Tannerella forsythia, Bacteroides fragilis and Bacteroides uniformis. Gram-positive anaerobic cocci were the more susceptible then Gram-positive rods. The pichtae oil was the more active towards Gram-positive bacteria then Gram-negative anaerobic rods.

Phân lập và tuyển chọn những chủng xạ khuẩn triển vọng đối kháng với tuyến trùng Pratylenchus sp. trong điều kiện phòng thí nghiệm

The study on isolation and selection of antagonistic Actinomyces against nematode Pratylenchus sp. was conducted in laboratory condition. Sixty-four strains of Actinomyces were isolated from vegetable farm soil collected from Tra Vinh and Can Tho. All Actinomyces strains were screened on hydrolytic ability of chitin and protein which are components of nematode cell wall, results showed that six strains i.e. 4A1, BM15, 8.11.1, 9.3.1, 5A6 and SM8 exhibited high chitinase and protease enzymes. Especially, three strains i.e 4A1, BM15, 8.11.1 expressed hydrolytic ability of chitin and protein higher than other strains. Investigation the effect of culture extract of strains 4A1, BM15, 8.11.1 and mix 4A1+BM15+8.11.1 in liquid medium ISP2 contained colloidal chitin on the survival of nematode in soil pot, results found that all treatments expressed effect in killing nematode Pratylenchus sp. with number of alive nematodes were significant lower than control, especially the treatment mixture of 3 strains (4A1+BM15+8.11.1) showed highest efficacy in killing nematode at 48 and 72 hours of testing.

Actinomyces denticolens as a causative agent of actinomycosis in animals.

The name “Actinomyces suis” was applied to each actinomycete isolate from swine actinomycosis by Grässer in 1962 and Franke in 1973. Nevertheless, this specific species was not included in the “Approved List of Bacterial Name” due to absence of the type cultures. Therefore, “Actinomyces suis” based on the description of Franke 1973 has been considered as “species incertae sedis”. We isolated a number of Actinomyces strains from swine. The representative strains of them was designated as Chiba 101 that was closely similar to the description in “Actinomyces suis” reported by Franke in 1973. Interestingly, it was found that the biological characteristics of these strains were also very similar to those of Actinomyces denticolens. Furthermore, the average nucleotide identity (ANI) value between strain Chiba 101 and the type-strain of Actinomyces denticolens (=DSM 20671T) was found to be 99.95%. Sequences of the housekeeping genes and 16S rRNA gene showed 100% homology. These results strongly suggested that “Actinomyces suis” Franke 1973 is the same species as Actinomyces denticolens. Since actinomycosis caused by Actinomyces denticolens have been demonstrated in horses recently, it is necessary to recognize that Actinomyces denticolens is the pathogenic actinomycetes in broader range of animals.

Antifungal activity change of Streptomyces rimosus MY02 mediated by confront culture with other microorganism

Streptomyces rimosus can produce antibacterial and antifungal antibiotics, which have important applications in medicine and agriculture. Seventy-nine microbial strains were employed to assay interaction between S. rimosus MY02 and different fungi, actinomyces, and bacteria when confront cultured on solid media. The results showed that the presence of a microorganism might affect the activity of another one. When S. rimosus MY02 confront cultured with other microorganisms, the inductive effect might be positive or negative. In this study, fungi showed to be effective elicitors, with a highest inductivity rate of 90.1%, and all of fungi showed positive induction behavior. Followed by bacteria with 59.6% of the tested bacterial strains showing positive inductivity, and the highest inductivity was 54.9%. Only six actinomyces (counting for 40% of the tested actinomyces strains) showed positive inductivity, and the highest induction rate of the strain NK413 was 34.1%. We also found that growth of most of bacteria or actinomyces which showed negative inductivity were similar or better than that of the strain MY02. However, the growth status of the strains was not positive related to inducing ability directly.

Metabolites from Actinomyces strain H6552 extract inhibit transforming growth factor-mediated pulmonary fibrosis

Purpose: To evaluate the effects of H6552 extract in inhibiting transforming growth factor (TGF)mediated pulmonary fibrosis in vitro and in vivo. Methods: Maximum-nontoxic dose (MNTD) of Actinomyces H6552 extract was determined using 3(4,5-dimethylthiazol-2-yl)-2,5-diphhenyltetrazolium bromide (MTT) assay. Effect of the extract on IMR90 lung fibroblasts proliferation was determined by calculating the population doubling time (PDT). Collagen gel contraction assay was carried out to determine cell contractility while α-smooth muscle actin (SMA) level in cells was evaluated by quantitative real-time polymerase chain reaction (PCR) and immunostaining methods. A bleomycin-induced ICR mouse model was used in the study to determine the effect of the extract in vivo. The animals received treatments in two regimes: early treatment in which treatment was given on Day 0 and delayed treatment with treatment on Days 5 and 10. The animals were sacrificed on Day 14 and the lungs removed for histopathological assessment. Results: The MNTD of the H6552 extract was 1625 ± 459.62 μg/ml. H6552 extract significantly reduced TGF- β-mediated cell proliferation, gel contraction and α-SMA expression. PDT was increased up to 83.84 % in the treated cells. Gel contraction was inhibited by the addition of 1000 μg/ml of H6552 extract. Immunostaining results revealed negligible α-SMA antibody staining after H6552 extract treatment at 500 μg/ml. The extract also inhibited lung injury (54 % reduction in Ashcroft score) when early treatment was provided. Delayed treatment with the extract did not show any significant changes in the animals. Conclusion: H6552 extract inhibited TGF-β-induced pulmonary fibrosis and elucidation of its bioactive metabolites may yield a potential agent to treat the disease.

Isolation of some thermophylic and acid-resistant Actinomyces strains biosynthesizing cellulase from pineapple waste

Isolation of some thermophylic and acid-resistant Actinomyces strains biosynthesizing cellulase from pineapple waste

Streptomyces chartreusis CP23X9 producing xylanase: biological characteristics and classification

Xylan is the major component of hemicellulose that makes up for plant cell. It is constructed by 1,4-β-linked-D-xylopyranosyl units with several side-groups. Xylan can be degraded by xylanase from microorganisms such as fungi, bacteria and actinomyces. Enzyme xylanase is widely applied in industry, such as textile, paper and pulp, and food production. In this study, an Actinomyces strain CP23X9 producing xylanase was characterized and identified. The results showed that strain CP23X9 can grow well on different media with a wide range of temperature between 15-45oC; pH 5-10, and salinity of 0-6%. On the agar plate, the strain has blue aerial mycelia and pale yellow vegetative mycelia. The mature spore chains appeared spirals, moderately long, bearing 10 to 50 spores each; the spore surface spiny. The strain utilized carbon sources such as D-glucose, D-xylose, D-mannitol, L-arabinose và L-rhamnose. Strain CP23X9 capable of extracellular enzymes producing, such as ligninase, protease, amylase and with high xylanase activity (42.7 U/ml). Based on the biological characteristics and phylogenetic analysis of 16S rDNA, it can be concluded that strain CP23X9 is close to Streptomyces chartreusis (99%), hence identified as Streptomyces chartreusis CP23X9. The xylanase activity of Streptomyces chartreusis CP23X9 will be used in improved bleaching abilities in future

Screening of antifungi endophytic actinomyces strains from Salvia przewalskii in Tibean Plateau

Twenty-four endophytic actinomycetes strains were isolated from the Salvia przewalskii in Tibetan Plateau of China by tablet coating method. Fusarium moniliforme, Helminthosporium turcicum and Bipolaris maydis were selected as indicator fungi to test the antimicrobial activities of these endophytic actinomycetes by tablet confrontation method. The results showed that 21 strains can produce antimicrobial substances which accounts for 85.7% of the total separates number. Four strains of endogenous actinomyces have more obvious antifungi activity. According to results of morphology and culture properties and 16S rDNA sequences of endophytic actinomyces, it is concluded that all of the isolates were streptomycetes trains.

Actinomyces haliotis sp. nov., a bacterium isolated from the gut of an abalone, Haliotis discus hannai

A novel, Gram-staining-positive, facultatively anaerobic, non-motile and coccus-shaped bacterium, strain WL80(T), was isolated from the gut of an abalone, Haliotis discus hannai, collected from the northern coast of Jeju in Korea. Optimal growth occurred at 30 °C, pH 7-8 and with 1% (w/v) NaCl. Phylogenetic analyses based on the 16S rRNA gene sequence revealed that strain WL80(T) fell within the cluster of the genus Actinomyces, with highest sequence similarity to the type strains of Actinomyces radicidentis (98.8% similarity) and Actinomyces urogenitalis (97.0% similarity). The major cellular fatty acids were C18 : 1ω9c and C16 : 0. Menaquinone-10 (H4) was the major respiratory quinone. The genomic DNA G+C content of the isolate was 70.4 mol%. DNA-DNA hybridization values with closely related strains indicated less than 7.6% genomic relatedness. The results of physiological, biochemical, chemotaxonomic and genotypic analyses indicated that strain WL80(T) represents a novel species of the genus Actinomyces, for which the name Actinomyces haliotis sp. nov. is proposed. The type strain is WL80(T) ( = KACC 17211(T) = JCM 18848(T)).

Experiment Research on Treatment of Landfill Leachate with Efficiency Microorganism

The landfill leachate is a kind of complicated waste water which is hard to be treated at present. In this paper seven dominant stains that can effectively degrade COD in leachate were isolated by increasing the concentration of leachate. The influence of treated time, temperature, pH on treatment efficiency of leachate with these dominant stains were studied. The results showed that five bacterial strains, one Actinomyces strain and one mould strain possess fairly high rate to eliminate COD in leachate. The optimum time of degradation of COD in leachate was 3 days, and the pH was suitable for strains which the best was 7. In a broad temperature range from 25°C to 35°C, the COD in leachate could be effectively degraded by all of seven strains.