Updated Review on Nocardia Species: 2006-2021.

This review serves as an update to the previous Nocardia 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.

Division of the genus Chryseobacterium: Observation of discontinuities in amino acid identity values, a possible consequence of major extinction events, guides transfer of nine species to the genus Epilithonimonas, eleven species to the genus Kaistella, and three species to the genus Halpernia gen. nov., with description of Kaistella daneshvariae sp. nov. and Epilithonimonas vandammei sp. nov. derived from clinical specimens.

The genus Chryseobacterium in the family Weeksellaceae is known to be polyphyletic. Amino acid identity (AAI) values were calculated from whole-genome sequences of species of the genus Chryseobacterium, and their distribution was found to be multi-modal. These naturally-occurring non-continuities were leveraged to standardise genus assignment of these species. We speculate that this multi-modal distribution is a consequence of loss of biodiversity during major extinction events, leading to the concept that a bacterial genus corresponds to a set of species that diversified since the Permian extinction. Transfer of nine species (Chryseobacterium arachidiradicis, Chryseobacterium bovis, Chryseobacterium caeni, Chryseobacterium hispanicum, Chryseobacterium hominis, Chryseobacterium hungaricum,, Chryseobacterium pallidum and Chryseobacterium zeae) to the genus Epilithonimonas and eleven (Chryseobacterium anthropi, Chryseobacterium antarcticum, Chryseobacterium carnis, Chryseobacterium chaponense, Chryseobacterium haifense, Chryseobacterium jeonii, Chryseobacterium montanum, Chryseobacterium palustre, Chryseobacterium solincola, Chryseobacterium treverense and Chryseobacterium yonginense) to the genus Kaistella is proposed. Two novel species are described: Kaistella daneshvariae sp. nov. and Epilithonimonas vandammei sp. nov. Evidence is presented to support the assignment of Planobacterium taklimakanense to a genus apart from Chryseobacterium, to which Planobacterium salipaludis comb nov. also belongs. The novel genus Halpernia is proposed, to contain the type species Halpernia frigidisoli comb. nov., along with Halpernia humi comb. nov., and Halpernia marina comb. nov.

A Real-Time Multiplex PCR Assay for Detection of Elizabethkingia Species and Differentiation between Elizabethkingia anophelis and E. meningoseptica.

Nosocomial infections of Elizabethkingia species can have fatal outcomes if not identified and treated properly. The current diagnostic tools available require culture and isolation, which can extend the reporting time and delay treatment. Using comparative genomics, we developed an efficient multiplex real-time PCR for the simultaneous detection of all known species of Elizabethkingia, as well as differentiating the two most commonly reported species, Elizabethkingia anophelis and Elizabethkingia meningoseptica.

Fly Reservoir Associated with Wohlfahrtiimonas Bacteremia in a Human.

Wohlfahrtiimonas species bacteria were isolated from the bloodstream of a patient with septicemia and wound myiasis. Environmental investigations identified a Wohlfahrtiimonas sp. among insects in the Americas and in a previously undescribed vector, the green bottle fly (Lucilia sericata). The isolates possibly represent a new species within the genus Wohlfahrtiimonas.

Lawsonella clevelandensis gen. nov., sp. nov., a new member of the suborder Corynebacterineae isolated from human abscesses.

Gram-stain-positive, partially acid-fast, non-spore-forming, anaerobic, catalase-positive, pleomorphic bacteria were isolated from human abscesses. Strains X1036T, X1698 and NML 120705, were recovered from a spinal abscess, a peritoneal abscess and a breast abscess respectively. A phylogenetic analysis of the 16S rRNA gene sequences showed that the strains shared 100 % similarity, and the nearest phylogenetic neighbour was Dietzia timorensis DSM 45568T (95%). Chemotaxonomic characteristics of the strains were consistent with those described for members of the suborder Corynebacterineae. Mycolic acids were detected using HPLC and one-dimensional TLC; whole-cell hydrolysates yielded meso-diaminopimelic acid with arabinose and galactose as the predominant sugars; the muramic acid acyl type was acetylated; the major menaquinone was MK-9 (96.3%); polar lipids detected were phosphatidylglycerol, phosphatidylinositol and an unknown glycophospholipid. Cellular fatty acids were hexadecanoic acid (C16 : 0), octadecenoic acid (C18 : 1ω9c) and decanoic acid (C10 : 0). Tuberculostearic acid was not detected. Based on the results of this polyphasic study, we conclude that these strains represent a novel genus and species within the suborder Corynebacterineae for which we propose the name Lawsonella clevelandensis gen. nov., sp. nov., with the type strain X1036T (=DSM 45743T=CCUG 66657T).

Kroppenstedtia pulmonis sp. nov. and Kroppenstedtia sanguinis sp. nov., isolated from human patients.

Three human clinical strains (W9323(T), X0209(T) and X0394) isolated from a lung biopsy, blood and cerebral spinal fluid, respectively, were characterised using a polyphasic taxonomic approach. Comparative analysis of the 16S rRNA gene sequences showed the three strains belong to two novel branches within the genus Kroppenstedtia: 16S rRNA gene sequence analysis of W9323(T) showed close sequence similarity to Kroppenstedtia eburnea JFMB-ATE(T) (95.3 %), Kroppenstedtia guangzhouensis GD02(T) (94.7 %) and strain X0209(T) (94.6 %); sequence analysis of strain X0209(T) showed close sequence similarity to K. eburnea JFMB-ATE(T) (96.4 %) and K. guangzhouensis GD02(T) (96.0 %). Strains X0209(T) and X0394 were 99.9 % similar to each other by 16S rRNA gene sequence analysis. The DNA-DNA relatedness was 94.6 %, confirming that X0209(T) and X0394 belong to the same species. Chemotaxonomic data for strains W9323(T) and X0209(T) were consistent with those described for the members of the genus Kroppenstedtia: the peptidoglycan was found to contain LL-diaminopimelic acid; the major cellular fatty acids were identified as iso-C15 and anteiso-C15; and the major menaquinone was identified as MK-7. Differences in endospore morphology, carbon source utilisation profiles, and cell wall sugar patterns of strains W9323(T) and X0209(T), supported by phylogenetic analysis, enabled us to conclude that the strains each represent a new species within the genus Kroppenstedtia, for which the names Kroppenstedtia pulmonis sp. nov. (type strain W9323(T) = DSM 45752(T) = CCUG 68107(T)) and Kroppenstedtia sanguinis sp. nov. (type strain X0209(T) = DSM 45749(T) = CCUG 38657(T)) are proposed.

Evaluation of new biomarker genes for differentiating Haemophilus influenzae from Haemophilus haemolyticus.

PCR detecting the protein D (hpd) and fuculose kinase (fucK) genes showed high sensitivity and specificity for identifying Haemophilus influenzae and differentiating it from H. haemolyticus. Phylogenetic analysis using the 16S rRNA gene demonstrated two distinct groups for H. influenzae and H. haemolyticus.

Using the BDFX40 Automated Continuous Blood Culture System to Isolate and Recover Streptobacillus moniliformis in the Presence of 0.05% SPS: A 55-Year, 56-Strain Retrospective Study.

Rat bite fever and Haverhill fever are often difficult to diagnose in a clinical setting. This difficulty results in part from clinicians and laboratory professionals not being able to reliably recover the causative agent Streptobacillus moniliformis using culture-based methods. After utilizing an automated continuous-monitoring blood culture bottle system, we showed that the organism can be reliably cultured when a blood volume inoculum of 10 mL is used. Further, we showed that when the above recommendation is followed, sodium polyanethole sulfonate (up to a concentration of 0.05% w/v) in commercially purchased blood culture bottle formulations seems to be inactivated, allowing for the growth and detection of S. moniliformis. Herein, we offer data and methods used to overcome these clinical limitations. This is a comprehensive study of the historical collection of S. moniliformis isolates maintained by our facility and believed to be the largest of its kind to date.

Genotypic differences between strains of the opportunistic pathogen Corynebacterium bovis isolated from humans, cows, and rodents.

Corynebacterium bovis is an opportunistic bacterial pathogen shown to cause eye and prosthetic joint infections as well as abscesses in humans, mastitis in dairy cattle, and skin disease in laboratory mice and rats. Little is known about the genetic characteristics and genomic diversity of C. bovis because only a single draft genome is available for the species. The overall aim of this study was to sequence and compare the genome of C. bovis isolates obtained from different species, locations, and time points. Whole-genome sequencing was conducted on 20 C. bovis isolates (six human, four bovine, nine mouse and one rat) using the Illumina MiSeq platform and submitted to various comparative analysis tools. Sequencing generated high-quality contigs (over 2.53 Mbp) that were comparable to the only reported assembly using C. bovis DSM 20582T (97.8 ± 0.36% completeness). The number of protein-coding DNA sequences (2,174 ± 12.4) was similar among all isolates. A Corynebacterium genus neighbor-joining tree was created, which revealed Corynebacterium falsenii as the nearest neighbor to C. bovis (95.87% similarity), although the reciprocal comparison shows Corynebacterium jeikeium as closest neighbor to C. falsenii. Interestingly, the average nucleotide identity demonstrated that the C. bovis isolates clustered by host, with human and bovine isolates clustering together, and the mouse and rat isolates forming a separate group. The average number of genomic islands and putative virulence factors were significantly higher (p<0.001) in the mouse and rat isolates as compared to human/bovine isolates. Corynebacterium bovis' pan-genome contained a total of 3,067 genes of which 1,354 represented core genes. The known core genes of all isolates were primarily related to ''metabolism" and ''information storage/processing." However, most genes were classified as ''function unknown" or "unclassified". Surprisingly, no intact prophages were found in any isolate; however, almost all isolates had at least one complete CRISPR-Cas system.

Draft Reference Genome Sequence of Corynebacterium mastitidis 16-1433, Isolated from a Mouse.

We report here a nearly complete draft genome sequence for a Corynebacterium mastitidis isolate from a mouse. The total read coverage is 198×, and the genome size is 2,264,319 bp with a 69.04% GC content. This genome complements the only other genome available for C. mastitidis, which was obtained from a sheep.

Evolutionary dynamics and genomic features of the Elizabethkingia anophelis 2015 to 2016 Wisconsin outbreak strain.

An atypically large outbreak of Elizabethkingia anophelis infections occurred in Wisconsin. Here we show that it was caused by a single strain with thirteen characteristic genomic regions. Strikingly, the outbreak isolates show an accelerated evolutionary rate and an atypical mutational spectrum. Six phylogenetic sub-clusters with distinctive temporal and geographic dynamics are revealed, and their last common ancestor existed approximately one year before the first recognized human infection. Unlike other E. anophelis, the outbreak strain had a disrupted DNA repair mutY gene caused by insertion of an integrative and conjugative element. This genomic change probably contributed to the high evolutionary rate of the outbreak strain and may have increased its adaptability, as many mutations in protein-coding genes occurred during the outbreak. This unique discovery of an outbreak caused by a naturally occurring mutator bacterial pathogen provides a dramatic example of the potential impact of pathogen evolutionary dynamics on infectious disease epidemiology.

Complete Genome Sequences of Four Strains from the 2015-2016 Elizabethkingia anophelis Outbreak.

The complete circularized genome sequences of selected specimens from the largest known Elizabethkingia anophelis outbreak to date are described here. Genomic rearrangements observed among the outbreak strains are discussed.