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Clinical Microbiology Reviews Apr 2015Actinomyces israelii has long been recognized as a causative agent of actinomycosis. During the past 3 decades, a large number of novel Actinomyces species have been... (Review)
Review
Actinomyces israelii has long been recognized as a causative agent of actinomycosis. During the past 3 decades, a large number of novel Actinomyces species have been described. Their detection and identification in clinical microbiology laboratories and recognition as pathogens in clinical settings can be challenging. With the introduction of advanced molecular methods, knowledge about their clinical relevance is gradually increasing, and the spectrum of diseases associated with Actinomyces and Actinomyces-like organisms is widening accordingly; for example, Actinomyces meyeri, Actinomyces neuii, and Actinomyces turicensis as well as Actinotignum (formerly Actinobaculum) schaalii are emerging as important causes of specific infections at various body sites. In the present review, we have gathered this information to provide a comprehensive and microbiologically consistent overview of the significance of Actinomyces and some closely related taxa in human infections.
Topics: Actinomyces; Actinomycosis; Anti-Bacterial Agents; Bacterial Typing Techniques; Classification; Humans; Microbial Sensitivity Tests
PubMed: 25788515
DOI: 10.1128/CMR.00100-14 -
Biomolecules Jan 2021The discovery and development of actinomycete secondary metabolites (ASMs) have played pivotal roles in the fields of human medicine and its related biotechnology...
The discovery and development of actinomycete secondary metabolites (ASMs) have played pivotal roles in the fields of human medicine and its related biotechnology sectors over the past several decades [...].
Topics: Actinobacteria; Actinomyces; Biological Products; Biotechnology; Chemistry, Pharmaceutical; Corynebacterium glutamicum; Drug Discovery; Humans; Multigene Family; Streptomyces
PubMed: 33494267
DOI: 10.3390/biom11020134 -
PloS One Feb 2010Periodontitis and caries are infectious diseases of the oral cavity in which oral biofilms play a causative role. Moreover, oral biofilms are widely studied as model...
Periodontitis and caries are infectious diseases of the oral cavity in which oral biofilms play a causative role. Moreover, oral biofilms are widely studied as model systems for bacterial adhesion, biofilm development, and biofilm resistance to antibiotics, due to their widespread presence and accessibility. Despite descriptions of initial plaque formation on the tooth surface, studies on mature plaque and plaque structure below the gum are limited to landmark studies from the 1970s, without appreciating the breadth of microbial diversity in the plaque. We used fluorescent in situ hybridization to localize in vivo the most abundant species from different phyla and species associated with periodontitis on seven embedded teeth obtained from four different subjects. The data showed convincingly the dominance of Actinomyces sp., Tannerella forsythia, Fusobacterium nucleatum, Spirochaetes, and Synergistetes in subgingival plaque. The latter proved to be new with a possibly important role in host-pathogen interaction due to its localization in close proximity to immune cells. The present study identified for the first time in vivo that Lactobacillus sp. are the central cells of bacterial aggregates in subgingival plaque, and that Streptococcus sp. and the yeast Candida albicans form corncob structures in supragingival plaque. Finally, periodontal pathogens colonize already formed biofilms and form microcolonies therein. These in vivo observations on oral biofilms provide a clear vision on biofilm architecture and the spatial distribution of predominant species.
Topics: Actinomyces; Bacteria; Bacterial Adhesion; Biofilms; Candida albicans; Dental Caries; Dental Plaque; Fusobacterium nucleatum; Host-Pathogen Interactions; Humans; In Situ Hybridization, Fluorescence; Lactobacillus; Mouth; Periodontitis; Phylogeny; Streptococcus; Tooth
PubMed: 20195365
DOI: 10.1371/journal.pone.0009321 -
BioMed Research International 2018are nonmotile, filamentous, Gram-positive bacteria that cause actinomycosis in immunodeficiency patients. Although the prognosis of actinomycosis is good, the diagnosis... (Review)
Review
are nonmotile, filamentous, Gram-positive bacteria that cause actinomycosis in immunodeficiency patients. Although the prognosis of actinomycosis is good, the diagnosis of actinomycosis is quite difficult. Recent studies on actinomycosis have shown that play an important role in various biological and clinical processes, such as the formation of dental plaque and the degradation of organics in the gastrointestinal tract. Here, the distribution of in the digestive tract, and different biological effects of actinomycosis, and its clinical association with inflammatory diseases are discussed. Furthermore, an overview of the most commonly used treatment methods and drugs used to treat infected alimentary canal diseases is presented.
Topics: Actinomyces; Actinomycosis; Gastrointestinal Diseases; Gram-Positive Bacteria; Humans
PubMed: 30225251
DOI: 10.1155/2018/3820215 -
Microbiology (Reading, England) Aug 2020
Topics: Actinomyces; Biofilms; Extracellular Vesicles; Humans; Lipoproteins; Microbiology; Periodicals as Topic; Quorum Sensing
PubMed: 32854815
DOI: 10.1099/mic.0.000969 -
Journal of Bacteriology Dec 2015Disulfide bonds are important for the stability and function of many secreted proteins. In Gram-negative bacteria, these linkages are catalyzed by thiol-disulfide... (Review)
Review
Disulfide bonds are important for the stability and function of many secreted proteins. In Gram-negative bacteria, these linkages are catalyzed by thiol-disulfide oxidoreductases (Dsb) in the periplasm. Protein oxidation has been well studied in these organisms, but it has not fully been explored in Gram-positive bacteria, which lack traditional periplasmic compartments. Recent bioinformatics analyses have suggested that the high-GC-content bacteria (i.e., actinobacteria) rely on disulfide-bond-forming pathways. In support of this, Dsb-like proteins have been identified in Mycobacterium tuberculosis, but their functions are not known. Actinomyces oris and Corynebacterium diphtheriae have recently emerged as models to study disulfide bond formation in actinobacteria. In both organisms, disulfide bonds are catalyzed by the membrane-bound oxidoreductase MdbA. Remarkably, unlike known Dsb proteins, MdbA is important for pathogenesis and growth, which makes it a potential target for new antibacterial drugs. This review will discuss disulfide-bond-forming pathways in bacteria, with a special focus on Gram-positive bacteria.
Topics: Actinomyces; Bacterial Proteins; Corynebacterium diphtheriae; Disulfides; Gene Expression Regulation, Bacterial; Oxidoreductases; Protein Folding
PubMed: 26644434
DOI: 10.1128/JB.00769-15 -
Molecules (Basel, Switzerland) Aug 2023Actinomycetes inhabit both terrestrial and marine ecosystems and are highly proficient in producing a wide range of natural products with diverse biological functions,... (Review)
Review
Actinomycetes inhabit both terrestrial and marine ecosystems and are highly proficient in producing a wide range of natural products with diverse biological functions, including antitumor, immunosuppressive, antimicrobial, and antiviral activities. In this review, we delve into the life cycle, ecology, taxonomy, and classification of actinomycetes, as well as their varied bioactive metabolites recently discovered between 2015 and 2023. Additionally, we explore promising strategies to unveil and investigate new bioactive metabolites, encompassing genome mining, activation of silent genes through signal molecules, and co-cultivation approaches. By presenting this comprehensive and up-to-date review, we hope to offer a potential solution to uncover novel bioactive compounds with essential activities.
Topics: Actinobacteria; Actinomyces; Ecosystem; Anti-Infective Agents; Biological Products
PubMed: 37570885
DOI: 10.3390/molecules28155915 -
BMC Genomics Dec 2023Actinomyces strains are commonly found as part of the normal microflora on human tissue surfaces, including the oropharynx, gastrointestinal tract, and female genital...
BACKGROUND
Actinomyces 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 and ATCC 51655 have been utilized in various studies, but their accurate species classification and description remain unresolved.
RESULTS
To 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 was 3.27 Mbp with a 68.0% GC content, and Actinomyces stomatis ATCC 51655 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 and ATCC 49340 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 and ATCC 51655 possessing 1,515 and 1,518 unique gene clusters, respectively. Additionally, genomic islands (GIs) prediction uncovered 24 putative GIs in strain ATCC 49340 and 16 in strain ATCC 51655, 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.
CONCLUSION
This study supports the classification of strains ATCC 49340 and ATCC 51655 as novel species within the Actinomyces, in which the name Actinomyces acetigenes sp. nov. (type strain ATCC 49340 = VPI D163E-3 = CCUG 34286 = CCUG 35339 ) and Actinomyces stomatis sp. nov. (type strain ATCC 51655 = PK606 = CCUG 33930) are proposed.
Topics: Humans; Female; Actinomyces; Phylogeny; Sequence Analysis, DNA; RNA, Ribosomal, 16S; Mouth; Nucleic Acid Hybridization; Nucleotides; DNA; DNA, Bacterial; Bacterial Typing Techniques; Fatty Acids
PubMed: 38049764
DOI: 10.1186/s12864-023-09831-2 -
Medicina (Kaunas, Lithuania) Oct 2021: species are part of the normal flora of humans and rarely cause disease. It is an uncommon cause of disease in humans. The clinical features of actinomycosis have...
: species are part of the normal flora of humans and rarely cause disease. It is an uncommon cause of disease in humans. The clinical features of actinomycosis have been described, and various anatomical sites (such as face, bones and joints, respiratory tract, genitourinary tract, digestive tract, central nervous system, skin, and soft tissue structures) can be affected. It is not easy to identify actinomycosis because it sometimes mimics cancer due to under-recognition. As new diagnostic methods have been applied, can now more easily be identified at the species level. Recent studies have also highlighted differences among species. We report a case of bacteremia with cutaneous actinomycosis. : A 66 years old male developed fever for a day with progressive right lower-leg erythematous swelling. Blood culture isolates yielded species, which was identified as by sequencing of the 16S rRNA gene. In addition, we searched for the term or actinomycosis cross-referenced with bacteremia or "blood culture" or "blood stream" from January 2010 to July 2020. The infectious diseases caused by species of from January 1977 to July 2020 were also reviewed. : The patient recovered well after intravenous ampicillin treatment. Poor oral hygiene was confirmed by dental examination. There were no disease relapses during the following period. Most cases of actinomycosis can be treated with penicillin. However, clinical alertness, risk factor evaluation, and identification of species can prevent inappropriate antibiotic or intervention. We also compiled a total of 18 cases of bacteremia after conducting an online database search. : In summary, we describe a case of fever and progressive cellulitis. species was isolated from blood culture, which was further identified as by 16S rRNA sequencing. The cellulitis improved after pathogen-directed antibiotics. Evaluation of risk factors in patients with bacteremia and further identification of the species are recommended for successful treatment.
Topics: Actinomyces; Actinomyces viscosus; Actinomycosis; Aged; Bacteremia; Humans; Male; RNA, Ribosomal, 16S
PubMed: 34684101
DOI: 10.3390/medicina57101064 -
Revista Chilena de Infectologia :... Aug 2011
Topics: Actinomyces
PubMed: 22052401
DOI: No ID Found