Bacillus licheniformis is a Gram-positive, endospore-forming bacterium with broad biotechnological applications. Thermophilic environments such as hot springs may harbor strains with unique biosynthetic capabilities relevant to drug discovery. In this study, we isolated two B. licheniformis strains (S3 and S4) from the Five Sisters hot spring in Yellowstone National Park (68 °C and 65 °C, pH 8) and performed whole-genome sequencing using both the Oxford Nanopore long read and Illumina platforms. Hybrid de novo assembly using Unicycler yielded genome sizes of 4.80 Mbp (S3, 14 contigs) and 4.79 Mbp (S4, 22 contigs); GC contents were 45.12% and 45.10%, and N50 values were 4,546,802 bp and 2,415,736 bp, for S3 and S4, respectively. Both strains were assigned to Multi-Locus Sequence Typing sequence type ST-42. Pangenome comparison with 61 complete B. licheniformis genomes revealed an open pangenome of 10,374 genes, with 3,272 core genes, 430 soft core, 1,250 shell, and 5,422 cloud genes. AMRFinderPlus identified the blaP, encoding a class A beta-lactamase and its regulatory elements (blaI and blaR1); erm(D), encoding a 23S rRNA methyltransferase conferring macrolide-lincosamide-streptogramin B resistance; and catA, encoding a chloramphenicol O-acetyltransferase that inactivates chloramphenicol through acetylation in both strains. A chromosomal arsBC locus was identified in both B. licheniformis S3 and S4, consistent with the arsenic-rich geothermal environment of Five Sisters hot spring. These findings highlight the biosynthetic potential of B. licheniformis strains isolated from extreme environments and provide a genomic foundation for future exploration of novel bioactive compounds with potential applications in drug discovery, agriculture, and biotechnology.
Staphylococcus pseudintermedius is an opportunistic bacterium previously associated with dogs but has recently been found in human infections, raising zoonotic concerns. Genomic characterization of human S. pseudintermedius isolates can provide preliminary information on antibiotic resistance, pathogenicity, and genomic features relevant to host range. Two S. pseudintermedius isolates (hereafter referred to as S. pseudintermedius EGH1 and S. pseudintermedius EGH2) from human clinical samples in Egypt were sequenced using the Illumina NovaSeq X Plus platform. To assess genetic relatedness to human S. pseudintermedius isolates worldwide, multilocus sequence typing (MLST), pangenome analysis, and antimicrobial resistance gene profiling were performed. The sequencing produced a total of 9,499,989 reads for S. pseudintermedius EGH1 and 9,567,531 reads for S. pseudintermedius EGH2. Sequences were assembled with Geneious Prime® 2025 and annotated using NCBI Prokaryotic Genome Annotation Pipeline v6.10. Pangenome analysis identified 9574 genes, comprising 1681 core genes (17.56%), 180 soft-core genes (1.88%), 837 shell genes (8.74%), and 6876 cloud genes (71.82%). MLST was conducted on human S. pseudintermedius genome assemblies using MLST v2.23.0. The analysis revealed both isolates as novel sequence types: S. pseudintermedius EGH1 was assigned ST-3037 with a new allele (purA-107), and S. pseudintermedius EGH2 was assigned ST-2874. Clonal relationships among S. pseudintermedius isolates were evaluated using the eBURST algorithm. This study presents the first next-generation genome sequencing and comparative genomic analysis of S. pseudintermedius isolates from humans in Egypt. Future studies integrating genomic, epidemiological, and phenotypic data are required.
Staphylococcus pseudintermedius is an opportunistic pathogen that is largely associated with canine hosts but is becoming more widely recognized as a zoonotic pathogen. Understanding its genetic and phenotypic properties, such as virulence factors and antimicrobial resistance (AMR) profiles, is critical for infection control and vaccine development. In this study, we isolated and molecularly characterized three S. pseudintermedius isolates from dogs (hereafter referred to as S. pseudintermedius D8) and humans (hereafter referred to as S. pseudintermedius H10 and S. pseudintermedius H11) in Egypt. All three isolates showed 100% sequence identity with the nuc gene of the S. pseudintermedius SP_11304-3A reference genome. Multilocus sequence typing (MLST) revealed novel sequence types (STs) in the three isolates. The AMR determinants varied substantially among the isolates. While the mecA gene was absent, blaZ was detected in the canine isolate, indicating beta-lactamase-mediated penicillin resistance. Additionally, tetK and tetM genes were found conferring tetracycline resistance in different isolates. Resistance genes for aminoglycosides, chloramphenicol, fusidic acid, macrolides, streptothricin, and trimethoprim were also identified. All isolates were positive for key virulence genes, including immune evasion (AdsA), coagulase (coa), immunoglobulin-binding protein (sbi/spsK), exfoliative toxin (speta), enterotoxins (se-int and siet), fibrinogen binding protein gene (fnbB), and two-component pore-forming leukocidin genes (lukF and lukS). The S. pseudintermedius H11 isolate uniquely harbored the neuraminidase gene (nanB), while none of the isolates contained the gene coding for immunoglobulin G binding protein (spsQ). These findings highlight the differences in virulence and antimicrobial resistance genes among these S. pseudintermedius isolates, underlining the need for global surveillance and molecular characterization of this pathogen.
Staphylococcus schleiferi and Staphylococcus coagulans, closely related bacterial species within the Staphylococcus genus, present a challenge in classification and diagnosis due to their close genetic proximity and overlapping phenotypic features. Moreover, our understanding of the virulence mechanisms in staphylococcal species, beyond the extensively studied Staphylococcus aureus, remains limited, underscoring the importance of using comparative data to enhance our insights into virulence within these bacterial species. This study employed a comprehensive approach, utilizing comparative genomics, to identify genomic distinctions between S. schleiferi and S. coagulans, aiming to address the challenges in the accurate classification and diagnosis of these organisms and identify unique features. Whole genome sequencing was performed on six clinical isolates, and their genomes were compared to identify variations in gene content and virulence factors. De novo assembly and annotation revealed two samples as S. coagulans and four samples as S. schleiferi. Analysis of the core genomes revealed conserved regions crucial for defining species identity, while accessory genomic elements contained unique genes, possibly impacting the pathogenicity of the species.
Staphylococcus schleiferi and Staphylococcus coagulans are opportunistic pathogens of animals and humans. They were previously classified as Staphylococcus schleiferi subs. schleiferi and Staphylococcus schleiferi subs. coagulans, respectively, and recently reclassified as separate species. S. coagulans, is frequently associated with dogs, whereas S. schleiferi is more commonly isolated from humans. Coagulase activity status is a defining characteristic of the otherwise closely related species. However, the use of coagulase tests originally developed to distinguish S. aureus from non-coagulase-producing staphylococci, for this purpose is questionable and the basis for their host preference has not been elucidated. In the current study, a putative coa gene was identified and correlated with coagulase activity measured using a chromogenic assay with human and bovine prothrombin (closely related to canine prothrombin). The results of the tests performed with human prothrombin showed greater reactivity of S. coagulans isolates from humans than isolates obtained from dogs with the same substrate. Our data suggest that unlike S. coagulans isolates from humans, isolates from dogs have more coagulase activity with bovine prothrombin (similar to canine prothrombin) than human prothrombin. Differences in nuc and 16s rRNA genes suggest a divergence in S. coagulans and S. schleiferi. Phenotypic and genotypic variation based on the number of IgG binding domains, and the numbers of tandem repeats in C-terminal fibronectin binding motifs was also found in protein A, and fibronectin-binding protein B respectively. This study identified a coa gene and associated phenotypic activity that differentiates S. coagulans and S. schleiferi and identified key phylogenetic and phenotypic differences between the species.
This study evaluated the concentrations of tetracycline, erythromycin, and sulfonamide in beef, eggs, and honey products sold at grocery stores and whether standard cooking to 160 °F (71 °C) reduced the concentrations of antimicrobials spiked into the evaluated food products. In June 2021, the concentrations of selected antimicrobials in 65 samples (8 beef, 48 eggs, 9 honey samples) purchased from grocery stores within Knoxville, Tennessee, were measured using enzyme-linked immunosorbent assays. The Kruskal–Wallis test was used to assess the differences in the median tetracycline concentrations across food types, while the Mann–Whitney test was used to compare the erythromycin residue concentrations between beef and honey. Linear regression was used to analyze whether standard cooking at 160 °F (71 °C) reduced antimicrobial concentrations. Detectable tetracycline concentrations were found in all beef (8/8, 100%), eggs (46/48, 96%), and honey (9/9, 100%) samples, with median concentrations of 7.73, 5.62, and 13.13 µg/kg, respectively. Honey had significantly higher tetracycline concentrations than eggs (p = 0.002). Detectable erythromycin concentrations were found in beef (5/8, 63%) and honey (9/9, 100%), with median concentrations of 0.14 µg/kg for beef and 0.48 µg/kg for honey. None of the antimicrobial concentrations found in the beef and egg products exceeded the U.S. FDA’s maximum residue limits (MRL). Sulfonamide concentrations were undetectable in the beef and egg products. The concentrations of tetracycline, erythromycin, and sulfonamide spiked into the food products did not change significantly in response to cooking to 160 °F (71 °C). The antimicrobial concentrations found in the selected commercial food products were below the MRL, and cooking appeared to not reduce the spiked antimicrobial concentrations in the evaluated food products.
We report here the genome sequences of 11 canine Staphylococcus pseudintermedius isolates from New York, New Hampshire, California, Pennsylvania, and Kansas. The sequencing information will enable spatial phylogenetic comparisons of staphylococcal species and other related species and will help in better understanding their virulence potential.
This paper outlines methods used to identify novel antigens for use in the development of serological assays. Specifically, we applied these methods to a neurogenic parasitic nematode of cervids called Parelaphostrongylus tenuis. This parasite is of particular concern in both wild and domestic ungulates as it causes significant neurological signs and definitive diagnosis is only possible post-mortem, necessitating the development of serologic assays for antemortem diagnosis. Proteins extracted from P. tenuis organisms were affinity isolated using antibodies enriched from seropositive moose ( Alces alces ). The proteins were analyzed using mass spectrometry and liquid chromatography to obtain amino acid sequences that were then cross-referenced to open reading frames predicted from an assembled transcriptome. An antigen of interest was assessed for immunogenic epitopes and subsequently synthesized into 10-mer synthetic overlapping peptides representing these regions. These synthetic peptides were then assessed for reactivity against positive and negative moose sera and demonstrated potential use as a serological assay in diagnostic laboratories. Known negative moose sera revealed significantly lower optical density when compared to the positive samples (p < 0.05). This method serves as a pipeline for the construction of diagnostic assays of pathogens in both human and veterinary medicine.
Staphylococcus pseudintermedius is an important cause of clinical infections in small-animal-veterinary medicine. Evolutionary changes of strains using multilocus sequence typing (MLST) have been observed among S . pseudintermedius in European countries and the United States. However, there are limited or no studies on the detection of methicillin resistant Staphylococcus pseudintermedius (MRSP) and predominating MLST strains in South Africa. Therefore, this study aimed to determine the molecular epidemiology of S . pseudintermedius in South Africa. Twenty-six, non-duplicate, clinical isolates from dogs were obtained as convenience samples from four provinces in South Africa. The Kirby Bauer disk diffusion test was used to determine antimicrobial susceptibility. We used Resfinder and the Comprehensive Antibiotic Resistance Database (CARD) to detect antimicrobial resistance genes. Virulence genes were identified using the virulence factor database and Basic Local Alignment Search Tool (BLASTN) on Geneious prime. geoBURST analysis was used to study relationships between MLST. Finally, the maximum likelihood phylogeny was determined using Randomized Axelerated Maximum Likelihood (RAxML). Twenty-three isolates were confirmed as S . pseudintermedius of which 14 were MRSP. In addition to β-lactam antimicrobials, MRSP isolates were resistant to tetracycline (85.7%), doxycycline (92.8%), kanamycin (92.8%), and gentamicin (85.7%). The isolates harbored antimicrobial resistance genes ( tetM , ermB , drfG , cat , aac(6’)-Ie-aph(2”)-Ia , ant(6)-Ia , and aph(3’)-III ) and virulence genes ( AdsA , geh , icaA , and lip) . MLST analysis showed that ST2228, ST2229, ST2230, ST2231, ST2232, ST2318, ST2326 and ST2327 are unique sequence types in South Africa. Whereas, previously reported major STs including ST45, ST71, ST181, ST551 and ST496 were also detected. The geoBURST and phylogenetic analysis suggests that the isolates in South Africa are likely genetically related to isolates identified in other countries. Highly resistant MRSP strains (ST496, ST71, and ST45) were reported that could present challenges in the treatment of canine infections in South Africa. Hence, we have gained a better understanding of the epidemiology of MRSP in the African continent, the genes involved in resistance and virulence factors associated with these organisms.
Respiratory syncytial virus (RSV) is the leading cause of respiratory illness in ruminants and infants. The G glycoprotein of RSV serves as the viral attachment ligand. Despite currently available vaccines, RSV immunity is insufficient, and re-infections occur. Vaccine studies employing the G-protein's 174-187 amino acids, representing the immunodominant domain, have protected mice and calves against infections. To investigate the causes of vaccination failure, we designed four synthetic peptides for the ruminant RSV isolates (391-2, Maryland-BRSV, European-BRSV, and ORSV) using the immune-dominant sequence and vaccinated mice groups with them. The produced antibodies targeting each peptide were evaluated using ELISA and flow cytometry to determine their reactivity against the linear antigen and the native form of the G protein, respectively. Antibodies responded to homologous and heterologous peptides as determined by ELISA. Using flow cytometry-analysis targeting the natively folded protein, most generated antibodies reacted only with their homologous strain. However, antibodies raised to 391-2 peptide reacted with homologous and heterologous Maryland-BRSV viral epitopes. Accordingly, inadequate immunity and recurring RSV infections might be attributed to variations of antibodies targeting the immunodominant region of the G-protein.
The aim of this study was to perform a phenotypic and molecular epidemiological survey to determine temporal changes in the antimicrobial resistance and population structure of methicillin-resistant Staphylococcus pseudintermedius (MRSP) in the United States. Samples from 200 S. pseudintermedius isolates were obtained from veterinary diagnostic facilities located in geographic regions sampled approximately ten years ago and compared to samples obtained in 2021. Kirby-Bauer disk diffusion was used to determine antimicrobial susceptibility. geoBURST analysis and MrBayes were used to infer relationships of isolates using MLST data. Almost all MRSP isolates (98%) in 2021 were multidrug-resistant with 21% of these isolates resistant to more than 16 antimicrobials. In 2010, 190 S. pseudintermedius isolates were collected and 141 of them were MRSP. From 2010-2021 there was a significant increase in resistance observed to all antibiotics tested except cephalothin and sulfonamides. Whereas ten years previously multilocus sequence types (ST) ST68 (35.7%), ST71 (10%), and ST84 (17.4%) predominated, these strains have been supplanted by other STs, notably ST45 (n = 14), ST155 (n = 9), ST181 (n = 13), ST496 (n = 9) and ST551 (n = 9). The newly prevalent STs are distantly related to ST68, ST71 and ST84 and most likely do not share any recent common ancestors. The population structure of MRSP is far more elastic than expected with new, highly resistant strains replacing the ones that predominated in the United States a decade ago. Antibiotic use may play a role in selection; however, the strains that were replaced were also multidrug-resistant and other factors are likely involved.
Foods that contain antibiotic residues have potential adverse health effects on consumers and provide selective pressure for the threat of antimicrobial resistance (AMR). This study’s objective was to measure tetracycline, sulfonamide, and erythromycin residues in beef, eggs, and honey sold as “antibiotic-free” at farmers’ markets in East Tennessee (East TN) in the United States (U.S.). Between July and September 2020, 36 “antibiotic-free” food products (9 beef, 18 egg, and 9 honey products) were purchased from East TN farmers’ markets and tested for tetracycline, sulfonamide, and erythromycin residues using competitive enzyme-linked immunosorbent assays (cELISA). All beef, egg, and honey products had tetracycline residue; the median concentrations were 51.75, 30.25, and 77.86 µg/kg, respectively. Sulfonamide residue was present in every sample of beef. Of 18 eggs, 11 eggs had detectable sulfonamide residue; the median concentrations were 3.50 and 1.22 µg/kg in beef and eggs, respectively. Each sample of beef and honey contained erythromycin residue; the median concentrations were 3.67 and 0.68 µg/kg, respectively. Overall, the median concentrations of tetracycline, sulfonamide, and erythromycin residues were below the maximum residue levels (MRLs) set in the U.S. for beef and eggs. Thus, the beef and eggs sold as “antibiotic-free” in East TN farmers’ markets can be considered safe for consumption. Safety determination for honey could not be made because MRLs have not been set for honey in the U.S. Because these residues should not be expected in “antibiotic-free” food products, it is important to further investigate the potential sources of these residues in these products.
In late 2019, a novel coronavirus began circulating within humans in central China. It was designated SARS-CoV-2 because of its genetic similarities to the 2003 SARS coronavirus (SARS-CoV). Now that SARS-CoV-2 has spread worldwide, there is a risk of it establishing new animal reservoirs and recombination with native circulating coronaviruses. To screen local animal populations in the United States for exposure to SARS-like coronaviruses, we developed a serological assay using the receptor binding domain (RBD) from SARS-CoV-2. SARS-CoV-2's RBD is antigenically distinct from common human and animal coronaviruses, allowing us to identify animals previously infected with SARS-CoV or SARS-CoV-2. Using an indirect enzyme-linked immunosorbent assay (ELISA) for SARS-CoV-2's RBD, we screened serum from wild and domestic animals for the presence of antibodies against SARS-CoV-2's RBD. Surprisingly prepandemic feline serum samples submitted to the University of Tennessee Veterinary Hospital were ∼50% positive for anti-SARS RBD antibodies. Some of these samples were serologically negative for feline coronavirus (FCoV), raising the question of the etiological agent generating anti-SARS-CoV-2 RBD cross-reactivity. We also identified several white-tailed deer from South Carolina with anti-SARS-CoV-2 antibodies. These results are intriguing, as cross-reactive antibodies toward SARS-CoV-2 RBD have not been reported to date. The etiological agent responsible for seropositivity was not readily apparent, but finding seropositive cats prior to the current SARS-CoV-2 pandemic highlights our lack of information about circulating coronaviruses in other species. IMPORTANCE We report cross-reactive antibodies from prepandemic cats and postpandemic South Carolina white-tailed deer that are specific for that SARS-CoV RBD. There are several potential explanations for this cross-reactivity, each with important implications to coronavirus disease surveillance. Perhaps the most intriguing possibility is the existence and transmission of an etiological agent (such as another coronavirus) with similarity to SARS-CoV-2's RBD region. However, we lack conclusive evidence of prepandemic transmission of a SARS-like virus. Our findings provide impetus for the adoption of a One Health Initiative focusing on infectious disease surveillance of multiple animal species to predict the next zoonotic transmission to humans and future pandemics.
Background - Equine pastern dermatitis (EPD) is a common multifactorial clinical syndrome in horses. Treatment can be difficult; pathogenesis and triggering factors cannot always be determined. Objectives - To assess risk factors for developing EPD in a large group of horses kept under the same conditions and to analyse whether or not a spot-on containing essential fatty acids and antimicrobial agents is able to prevent the development of EPD or accelerate the healing process. Animals - Each year 50 young, privately owned, warmblood horses were prospectively included. Methods - All horses were examined weekly between August and October for the presence of typical EPD skin lesions. Additionally, in the first year, horses were randomly divided into three subgroups of intervention. The pastern areas were treated once weekly either with 0.6 mL of a spot-on containing essential fatty acids and aromatic oils, or a preparation containing additional antibacterial phytosphingosine, or not at all. Results - Nonpigmented pastern areas were affected significantly more often than pigmented pastern areas (P < 0.0001). The interaction between moisture and opportunistic pathogens seemed to be a major triggering factor for EPD. There was no difference in the occurrence of EPD in the three subgroups. The lesion scores of affected limbs in both spot-on groups were significantly lower compared to the control group. Conclusion and clinical importance - Moisture and lack of pigmentation predisposed to EPD. Topical application of the tested spot-on once weekly did not prevent the disease. A positive effect of both spot-on products on the severity of EPD lesions was detected.
BACKGROUND Demodex gatoi is a contagious ectoparasite that causes pruritic dermatitis in otherwise healthy cats. The diagnosis of this mite can be difficult, and its prevalence is unknown. OBJECTIVES The goal of this study was to identify the prevalence of D. gatoi in a population of cats with no known previous exposure to treatments using real-time PCR and superficial skin scrapings. ANIMALS Fifty cats from shelters and 50 cats from feral populations of eastern Tennessee were included in this study. MATERIALS AND METHODS To identify the presence of D. gatoi, superficial skin scrapings and plucked hairs were collected from multiple sites for microscopic and PCR evaluation, respectively. RESULTS Ten of 100 cats were positive for D. gatoi. Nine cats had a positive PCR for D. gatoi with negative skin scrapings. One mite was identified on superficial skin scrapings from one cat, which was negative on PCR. Four of 50 feral cats (8%) were positive for D. gatoi. Of the shelter cats, four of 20 stray cats (20%) and two of 30 owner-surrendered cats (6.67%) were positive. Only one of 10 positive cats had skin lesions. CONCLUSIONS AND CLINICAL RELEVANCE These findings demonstrate that asymptomatic cats represent a source of infection for D. gatoi to healthy cats. This mite should be considered a differential diagnosis in pruritic cats with a history of potential exposure. Additionally, skin scrapings appear to be insensitive; thus, multiple diagnostic tests, including PCR, should be performed to identify the presence of D. gatoi.
Background Mycobacteria are found in many environmental conditions and infect a variety of species, including rodents and rabbits. Guinea pigs are used experimentally as a model for Mycobacterium tuberculosis, but natural mycobacteriosis in guinea pigs has not been reported. Case presentation A 1.5-year-old female guinea pig was found acutely deceased with no premonitory illness. On gross post-mortem examination, multifocal to coalescing, raised, firm, pale tan nodules with discrete, irregular margins were noted over the surfaces of all lung lobes. Histopathology revealed nodules composed of clustered foamy macrophages and multinucleated giant cells containing numerous bacterial rods. Similar bacteria-laden macrophages were noted within sections of the liver, heart, palpebral conjunctiva, duodenum, and cecum. Polymerase chain reaction was performed on tissues collected during post-mortem examination. The 16S rRNA gene product was sequenced and was identical to the Mycobacterium genavense type strain. Conclusions To the best of the author's knowledge, this report details the first documented case of Mycobacterium genvaense infection in a guinea pig and a follow up investigation of close-contact animals. Given their experimental susceptibility and this clinical case report, mycobacteriosis should be considered as a differential in guinea pigs exhibiting weight loss in the absence of other clinical signs. With the potential for zoonotic transmission in immunosuppressed individuals, precautions should be taken to safeguard human health in cases of guinea pigs with suspected M. genavense infection.
Background Understanding drivers of multidrug resistance (MDR) and methicillin resistance, which have increased among canine staphylococcal isolates, is essential for guiding antimicrobial use practices. Therefore, the objective of this study was to identify predictors of MDR and methicillin resistance among Staphylococcus spp. commonly isolated from canine clinical specimens. Methods This retrospective study used records of canine specimens submitted to the University of Tennessee College of Veterinary Medicine Clinical Bacteriology Laboratory for bacterial culture and antimicrobial susceptibility testing between 2006 and 2017. Records from 7,805 specimens positive for the following Staphylococcus species were included for analysis: Staphylococcus pseudintermedius, Staphylococcus aureus, Staphylococcus coagulans (formerly Staphylococcus schleiferi subspecies coagulans), and Staphylococcus schleiferi (formerly S. schleiferi subsp. schleiferi). Generalized linear regression models were fit using generalized estimating equations (GEE) to identify predictors of MDR (defined as resistance to three or more antimicrobial classes) and methicillin resistance among these isolates. Results Multidrug resistance (42.1%) and methicillin resistance (31.8%) were relatively common. Isolates from skeletal (joint and bone) specimens had the highest levels of MDR (51.3%) and methicillin resistance (43.6%), followed by cutaneous specimens (45.8% multidrug-resistant, 37.1% methicillin resistant). Staphylococcus species, specimen site, and clinical setting were significant (p < 0.01) predictors of both outcomes. Compared to S. pseudintermedius, S. schleiferi had higher odds of methicillin resistance, while S. coagulans and S. schleiferi had lower odds of MDR. The odds of both MDR and methicillin resistance for isolates from hospital patient specimens were significantly higher than those from referral patients for urine/bladder and otic specimens. Odds of MDR among isolates from skeletal specimens of hospital patients were also higher than those of referral patients. Conclusions Staphylococcus isolates in this study had substantial levels of MDR and methicillin resistance. Differences in the odds of these outcomes between referral and hospital patient isolates did not persist for all specimen sites, which may reflect differences in diagnostic testing and antimicrobial use practices with respect to body site or system. Judicious antimicrobial use, informed by culture and susceptibility testing, is important to limit treatment failures and curb selection pressure.
Staphylococcus aureus (SA) is a significant and well-recognized causative organism of bacterial osteomyelitis. Osteomyelitis is an inflammatory bone disease characterized by progressive bone destruction and loss. This disease causes significant morbidity and mortality to the patient and poses therapeutic challenges for clinicians. To improve the efficacy of therapeutic strategies to combat bacterial osteomyelitis, there is a need to define the molecular epidemiology of bacterial organisms more clearly and further the understanding of the pathogenesis of SA osteomyelitis. We conducted in vitro characterization of the pathogenic capabilities of an isolate of SA ST398 derived from a clinical case of osteomyelitis in a goat. We also report a rodent mandibular defect model to determine the ability of ST398 to cause reproducible osteomyelitis. Our results indicate that ST398 can invade and distort pre-osteoblastic cells in culture, induce significant inflammation and alter expression of osteoregulatory cytokines. We also demonstrate the ability of ST398 to induce osteomyelitis in a rat mandibular model. When compiled, these data support ST398 as a competent osteomyelitis pathogen.
Veterinary DermatologyEarly View Abstract Prevalence of Demodex gatoi in shelter and feral cats in the East Tennessee region S. BAIZ, S. BAIZ Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this authorL. FRANK, L. FRANK Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this authorE. DRAKE, E. DRAKE Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this authorS. KANIA, S. KANIA Department of Biomedical and Diagnostic Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this author S. BAIZ, S. BAIZ Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this authorL. FRANK, L. FRANK Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this authorE. DRAKE, E. DRAKE Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this authorS. KANIA, S. KANIA Department of Biomedical and Diagnostic Sciences, University of Tennessee, Knoxville, TN, USASearch for more papers by this author First published: 06 June 2022 https://doi.org/10.1111/vde.13087Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Early ViewOnline Version of Record before inclusion in an issue RelatedInformation