Abstract
Actinomycosis is a chronic, suppurative, granulomatous infectious disease, caused by different species of Actinomyces bacteria. To date, 26 validly published Actinomyces species have been described as part of a normal human microbiota or from human clinical specimens. Due to the rapid spread of new, modern diagnostic procedures, 13 of 26 of these species have been described in this century and the Actinomycetaceae family has undergone several taxonomic revisions, including the introduction of many novel species termed Actinomyces-like organisms (ALOs). There is scarce data available on the role of these novel bacterial species in various infectious processes in human medicine. The aim of this review is to provide a comprehensive overview of Actinomyces and closely related organisms involved in human diseases—with a special focus on newly described species—in particular their role in genitourinary tract infections in females and males.
Highlights
A long time passed before the species of the genus was described in 1951: Actinomyces naeslundii was obtained from the oral samples of the mouths of patients implicated with actinomycotic lesions [6], while two other species were descovered only a few years later: A. odontolyticus from deep carious dentine (1958) and Actinomyces viscosus from the periodontal plaque in hamsters (1969) [7,8,9]
It is interesting to note that—so far—all Actinomyces species were isolated from the microbiota associated with humans and animals, while actinomycetes are usually soil dwelling bacteria, ubiquitous in the environment; e.g., A. israelii may be detected in decaying organic matters [10] and Rao et al isolated Actinomyces naturae for the first time from chlorinated, solvent-contaminated groundwater in 2012 [11]
Presence of various and commercial biochemical kits; these tests spectrometry often lead to systems and the on available database, but improvement this method is needed the for databases a definitive misidentification the speciesand even genus-level of of strains
Summary
The name of the genus originates from the greek words: aktinos (ray) and mykes (fungus), which corresponds to the radial arrangement of the bacterial filaments (resembling hyphae) and the possession of reproductive asexual spores, typical for filamentous fungi [42]. The identification and differentiation of the anaerobic Gram-positive rods and species belonging to the genus Actinomyces may cause major troubles for clinical microbiology laboratories in terms of labor and the time-consuming nature of the process when conventional (biochemical reaction-based) methods are used [55]. 3) [60,61].ofThe method enzymes allows excellent, rapid and accurate identification at the on the detection theMALDI-TOF presence of various (e.g., oxidase, urease, catalase, fermentation of genus species identification remains uncertain and largely depends on the mass sugars,level, and but indol production) and commercial biochemical kits; these tests spectrometry often lead to systems and the on available database, but improvement this method is needed the for databases a definitive misidentification the speciesand even genus-level of of strains [56]. There identified that the FimP and FimA fimbriae require a sortase-like genes to assemble type 1 and 2 fimbriae, respectively, as both contain a pilin motif and an E-box, which are common features of Gram-positive bacterial major pilin subunits [78,79,80]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
