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Clinical Microbiology Reviews Dec 2022This review serves as an update to the previous review by Brown-Elliott et al. published in 2006 (B. A. Brown-Elliott, J. M. Brown, P. S. Conville, and R. J. Wallace.... (Review)
Review
This review serves as an update to the previous review by Brown-Elliott et al. published in 2006 (B. A. Brown-Elliott, J. M. Brown, P. S. Conville, and R. J. Wallace. Jr., Clin Microbiol Rev 19:259-282, 2006, https://doi.org/10.1128/CMR.19.2.259-282.2006). Included is a discussion on the taxonomic expansion of the genus, current identification methods, and the impact of new technology (including matrix-assisted laser desorption ionization-time of flight [MALDI-TOF] and whole genome sequencing) on diagnosis and treatment. Clinical manifestations, the epidemiology, and geographic distribution are briefly discussed. An additional section on actinomycotic mycetoma is added to address this often-neglected disease.
Topics: Nocardia; Bacterial Typing Techniques; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 36314911
DOI: 10.1128/cmr.00027-21 -
Journal of Clinical Microbiology Jan 2018species are a complex group of organisms considered to belong to the aerobic actinomycetes. Of the validly described species, many have been implicated as the cause of... (Review)
Review
species are a complex group of organisms considered to belong to the aerobic actinomycetes. Of the validly described species, many have been implicated as the cause of serious human infections, especially in immunocompromised patients. The genus has a complicated taxonomic history; this is especially true for , the type species of the genus and previously the most frequently reported nocardial taxon from human specimens. We provide background on the current taxonomy of , with a focus on clinically relevant species, and discuss the currently available methods used to accurately identify isolates to the species, complex, or group level.
Topics: Algorithms; Bacteriological Techniques; Humans; Multilocus Sequence Typing; Nocardia; Nocardia Infections; Nocardia asteroides; Phylogeny; Species Specificity; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 29118169
DOI: 10.1128/JCM.01419-17 -
Clinical Microbiology Reviews Apr 2006The recent explosion of newly described species of Nocardia results from the impact in the last decade of newer molecular technology, including PCR restriction enzyme... (Review)
Review
The recent explosion of newly described species of Nocardia results from the impact in the last decade of newer molecular technology, including PCR restriction enzyme analysis and 16S rRNA sequencing. These molecular techniques have revolutionized the identification of the nocardiae by providing rapid and accurate identification of recognized nocardiae and, at the same time, revealing new species and a number of yet-to-be-described species. There are currently more than 30 species of nocardiae of human clinical significance, with the majority of isolates being N. nova complex, N. abscessus, N. transvalensis complex, N. farcinica, N. asteroides type VI (N. cyriacigeorgica), and N. brasiliensis. These species cause a wide variety of diseases and have variable drug susceptibilities. Accurate identification often requires referral to a reference laboratory with molecular capabilities, as many newer species are genetically distinct from established species yet have few or no distinguishing phenotypic characteristics. Correct identification is important in deciding the clinical relevance of a species and in the clinical management and treatment of patients with nocardial disease. This review characterizes the currently known pathogenic species of Nocardia, including clinical disease, drug susceptibility, and methods of identification.
Topics: Anti-Bacterial Agents; Bacteriological Techniques; Culture Media; DNA, Bacterial; Humans; Lung Diseases; Microbial Sensitivity Tests; Nocardia; Nocardia Infections; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; RNA, Bacterial; RNA, Ribosomal, 16S; Skin Diseases; Species Specificity
PubMed: 16614249
DOI: 10.1128/CMR.19.2.259-282.2006 -
Journal of Microbiology and... Jul 2018The genus is a phylogenetically and catabolically diverse group that has been isolated from diverse environments, including polar and alpine regions, for its versatile... (Review)
Review
The genus is a phylogenetically and catabolically diverse group that has been isolated from diverse environments, including polar and alpine regions, for its versatile ability to degrade a wide variety of natural and synthetic organic compounds. Their metabolic capacity and diversity result from their diverse catabolic genes, which are believed to be obtained through frequent recombination events mediated by large catabolic plasmids. Many rhodococci have been used commercially for the biodegradation of environmental pollutants and for the biocatalytic production of high-value chemicals from low-value materials. Recent studies of their physiology, metabolism, and genome have broadened our knowledge regarding the diverse biotechnological applications that exploit their catabolic enzymes and pathways.
Topics: Biocatalysis; Biodegradation, Environmental; Biotechnology; Cholesterol; Environmental Pollutants; Genome, Bacterial; Industrial Microbiology; Lignin; Metabolic Networks and Pathways; Phylogeny; Plasmids; Rhodococcus; Soil Microbiology; Terpenes; Xylenes
PubMed: 29913546
DOI: 10.4014/jmb.1712.12017 -
ELife Dec 2017The acquisition of a virulence plasmid is sufficient to turn a beneficial strain of bacteria into a pathogen.
The acquisition of a virulence plasmid is sufficient to turn a beneficial strain of bacteria into a pathogen.
Topics: Bacterial Proteins; Biological Evolution; Plant Diseases; Plasmids; Rhodococcus; Virulence
PubMed: 29231817
DOI: 10.7554/eLife.33383 -
Applied Microbiology and Biotechnology Oct 2020Bacteria belonging to Rhodococcus genus represent ideal candidates for microbial biotechnology applications because of their metabolic versatility, ability to degrade a... (Review)
Review
Bacteria belonging to Rhodococcus genus represent ideal candidates for microbial biotechnology applications because of their metabolic versatility, ability to degrade a wide range of organic compounds, and resistance to various stress conditions, such as metal toxicity, desiccation, and high concentration of organic solvents. Rhodococcus spp. strains have also peculiar biosynthetic activities that contribute to their strong persistence in harsh and contaminated environments and provide them a competitive advantage over other microorganisms. This review is focused on the metabolic features of Rhodococcus genus and their potential use in biotechnology strategies for the production of compounds with environmental, industrial, and medical relevance such as biosurfactants, bioflocculants, carotenoids, triacylglycerols, polyhydroxyalkanoate, siderophores, antimicrobials, and metal-based nanostructures. These biosynthetic capacities can also be exploited to obtain high value-added products from low-cost substrates (industrial wastes and contaminants), offering the possibility to efficiently recover valuable resources and providing possible waste disposal solutions. Rhodococcus spp. strains have also recently been pointed out as a source of novel bioactive molecules highlighting the need to extend the knowledge on biosynthetic capacities of members of this genus and their potential utilization in the framework of bioeconomy. KEY POINTS: • Rhodococcus possesses promising biosynthetic and bioconversion capacities. • Rhodococcus bioconversion capacities can provide waste disposal solutions. • Rhodococcus bioproducts have environmental, industrial, and medical relevance. Graphical abstract.
Topics: Biotechnology; Industrial Waste; Refuse Disposal; Rhodococcus; Triglycerides
PubMed: 32918579
DOI: 10.1007/s00253-020-10861-z -
Applied and Environmental Microbiology Sep 2019Some species belonging to the genus, such as , , and , are known to be oleaginous microorganisms, since they are able to accumulate triacylglycerols (TAG) at more than... (Review)
Review
Some species belonging to the genus, such as , , and , are known to be oleaginous microorganisms, since they are able to accumulate triacylglycerols (TAG) at more than 20% of their weight (dry weight). Oleaginous rhodococci are promising microbial cell factories for the production of lipids to be used as fuels and chemicals. Cells could be engineered to create strains capable of producing high quantities of oils from industrial wastes and a variety of high-value lipids. The comprehensive understanding of carbon metabolism and its regulation will contribute to the design of a reliable process for bacterial oil production. Bacterial oleagenicity requires an integral configuration of metabolism and regulatory processes rather than the sole existence of an efficient lipid biosynthesis pathway. In recent years, several studies have been focused on basic aspects of TAG biosynthesis and accumulation using PD630 and RHA1 strains as models of oleaginous bacteria. The combination of results obtained in these studies allows us to propose a metabolic landscape for oleaginous rhodococci. In this context, this article provides a comprehensive and integrative view of different metabolic and regulatory attributes and innovations that explain the extraordinary ability of these bacteria to synthesize and accumulate TAG. We hope that the accessibility to such information in an integrated way will help researchers to rationally select new targets for further studies in the field.
Topics: Rhodococcus; Triglycerides
PubMed: 31324625
DOI: 10.1128/AEM.00498-19 -
Molecules (Basel, Switzerland) Aug 2021Bacteria belonging to the genus are frequent components of microbial communities in diverse natural environments. Some rhodococcal species exhibit the outstanding... (Review)
Review
Bacteria belonging to the genus are frequent components of microbial communities in diverse natural environments. Some rhodococcal species exhibit the outstanding ability to produce significant amounts of triacylglycerols (TAG) (>20% of cellular dry weight) in the presence of an excess of the carbon source and limitation of the nitrogen source. For this reason, they can be considered as oleaginous microorganisms. As occurs as well in eukaryotic single-cell oil (SCO) producers, these bacteria possess specific physiological properties and molecular mechanisms that differentiate them from other microorganisms unable to synthesize TAG. In this review, we summarized several of the well-characterized molecular mechanisms that enable oleaginous rhodococci to produce significant amounts of SCO. Furthermore, we highlighted the ability of these microorganisms to degrade a wide range of carbon sources coupled to lipogenesis. The qualitative and quantitative oil production by rhodococci from diverse industrial wastes has also been included. Finally, we summarized the genetic and metabolic approaches applied to oleaginous rhodococci to improve SCO production. This review provides a comprehensive and integrating vision on the potential of oleaginous rhodococci to be considered as microbial biofactories for microbial oil production.
Topics: Biofuels; Carbon; Lipogenesis; Oils; Phylogeny; Rhodococcus
PubMed: 34443455
DOI: 10.3390/molecules26164871 -
Folia Microbiologica Oct 2021Rhodococcus spp. strains are widespread in diverse natural and anthropized environments thanks to their high metabolic versatility, biodegradation activities, and unique... (Review)
Review
Rhodococcus spp. strains are widespread in diverse natural and anthropized environments thanks to their high metabolic versatility, biodegradation activities, and unique adaptation capacities to several stress conditions such as the presence of toxic compounds and environmental fluctuations. Additionally, the capability of Rhodococcus spp. strains to produce high value-added products has received considerable attention, mostly in relation to lipid accumulation. In relation with this, several works carried out omic studies and genome comparative analyses to investigate the genetic and genomic basis of these anabolic capacities, frequently in association with the bioconversion of renewable resources and low-cost substrates into triacylglycerols. This review is focused on these omic analyses and the genetic and metabolic approaches used to improve the biosynthetic and bioconversion performance of Rhodococcus. In particular, this review summarizes the works that applied heterologous expression of specific genes and adaptive laboratory evolution approaches to manipulate anabolic performance. Furthermore, recent molecular toolkits for targeted genome editing as well as genome-based metabolic models are described here as novel and promising strategies for genome-scaled rational design of Rhodococcus cells for efficient biosynthetic processes application.
Topics: Biodegradation, Environmental; Genome, Bacterial; Genomics; Metabolic Engineering; Rhodococcus; Systems Biology
PubMed: 34215934
DOI: 10.1007/s12223-021-00892-y -
Molecular Microbiology Jul 2019Rhodococcus equi is the only recognized animal pathogenic species within an extended genus of metabolically versatile Actinobacteria of considerable biotechnological... (Review)
Review
Rhodococcus equi is the only recognized animal pathogenic species within an extended genus of metabolically versatile Actinobacteria of considerable biotechnological interest. Best known as a horse pathogen, R. equi is commonly isolated from other animal species, particularly pigs and ruminants, and causes severe opportunistic infections in people. As typical in the rhodococci, R. equi niche specialization is extrachromosomally determined, via a conjugative virulence plasmid that promotes intramacrophage survival. Progress in the molecular understanding of R. equi and its recent rise as a novel paradigm of multihost adaptation has been accompanied by an unusual nomenclatural instability, with a confusing succession of names: "Prescottia equi", "Prescotella equi", Corynebacterium hoagii and Rhodococcus hoagii. This article reviews current advances in the genomics, biology and virulence of this pathogenic actinobacterium with a unique mechanism of plasmid-transferable animal host tropism. It also discusses the taxonomic and nomenclatural issues around R. equi in the light of recent phylogenomic evidence that confirms its membership as a bona fide Rhodococcus.
Topics: Actinomycetales Infections; Animals; Genomics; Horses; Phylogeny; Plasmids; Rhodococcus; Rhodococcus equi; Swine; Virulence
PubMed: 31099908
DOI: 10.1111/mmi.14267