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Frontiers in Cellular and Infection... 2022Hybrid sturgeon is the main species of sturgeon cultured in China, with the advantages of a fast growth rate, early sexual maturity, fertile offspring, and more stable...
Hybrid sturgeon is the main species of sturgeon cultured in China, with the advantages of a fast growth rate, early sexual maturity, fertile offspring, and more stable genetic traits. In May 2021, a large number of deaths characterized by superficial hemorrhage and liver damage occurred in a sturgeon farm in Yichang, Hubei Province, which posed a significant risk to hybrid sturgeon captive breeding. We isolated a pathogenic bacterium named D-59 from the diseased sturgeon with apparent symptoms. The pathogen was identified as using 16S rRNA gene phylogenetic analysis combined with biochemical identification. Regression experiments showed that D-59 exhibited clinical signs similar to those of diseased sturgeon in the farm after intraperitoneal injection into hybrid sturgeon. High-throughput sequencing of gut microbes in D-59-infected sturgeon showed that the number of gut microbial species decreased in infected sturgeon, the number of some intestinal commensal bacteria decreased, and the balance of the intestinal microorganisms was disrupted. Histopathological sections indicated many inflammatory cells, congestion, and even necrosis in the tissue of diseased sturgeon. Analysis of blood indexes revealed an increase in the proportion of mononuclear cells and a decrease in the proportion of lymphocytes in the peripheral blood of diseased sturgeon. Significantly elevated serum levels of aspartate aminotransferase and alanine aminotransferase, whereas alkaline phosphatase, total protein, albumin, and globulin were decreased in diseased sturgeon. Antimicrobial susceptibility tests demonstrated that D-59 is susceptible to florfenicol, enrofloxacin, and neomycin sulfate. This study aimed to highlight the dangers of infection during hybrid sturgeon culture and to provide recommendations for diagnosis and treatment.
Topics: Animals; RNA, Ribosomal, 16S; Phylogeny; Enrofloxacin; Alkaline Phosphatase; Alanine Transaminase; Fishes; Neomycin; Aspartate Aminotransferases; Albumins; Anti-Infective Agents
PubMed: 36275022
DOI: 10.3389/fcimb.2022.1029692 -
Scientific Reports Apr 2017Staphylococcus sciuri is a bacterial pathogen associated with infections in animals and humans, and represents a reservoir for the mecA gene encoding...
Staphylococcus sciuri is a bacterial pathogen associated with infections in animals and humans, and represents a reservoir for the mecA gene encoding methicillin-resistance in staphylococci. No S. sciuri siphophages were known. Here the identification and characterization of two temperate S. sciuri phages from the Siphoviridae family designated ϕ575 and ϕ879 are presented. The phages have icosahedral heads and flexible noncontractile tails that end with a tail spike. The genomes of the phages are 42,160 and 41,448 bp long and encode 58 and 55 ORFs, respectively, arranged in functional modules. Their head-tail morphogenesis modules are similar to those of Staphylococcus aureus ϕ13-like serogroup F phages, suggesting their common evolutionary origin. The genome of phage ϕ575 harbours genes for staphylokinase and phospholipase that might enhance the virulence of the bacterial hosts. In addition both of the phages package a homologue of the mecA gene, which is a requirement for its lateral transfer. Phage ϕ879 transduces tetracycline and aminoglycoside pSTS7-like resistance plasmids from its host to other S. sciuri strains and to S. aureus. Furthermore, both of the phages efficiently adsorb to numerous staphylococcal species, indicating that they may contribute to interspecies horizontal gene transfer.
Topics: Gene Transfer, Horizontal; Genes, Bacterial; Genome, Viral; Genomics; Host Specificity; Metalloendopeptidases; Phospholipases; Plasmids; Staphylococcus; Staphylococcus Phages; Transduction, Genetic; Virus Attachment
PubMed: 28406168
DOI: 10.1038/srep46319 -
Microorganisms May 2020In addition to the industrial and biomedical applications of lithium, information on the tolerance of microorganisms to high Li concentrations in natural biological...
In addition to the industrial and biomedical applications of lithium, information on the tolerance of microorganisms to high Li concentrations in natural biological systems is limited. Strain LCHXa is a novel free-living Gram-positive, non-motile bacterium strain isolated from water samples taken at Laguna Chaxa, a non-industrial water body with the highest soluble Li content (33 mM LiCl) within the Salar de Atacama basin in northern Chile. Enrichment was conducted in Luria-Bertani (LB) medium supplemented with 1 M LiCl. Strain LCHXa was a Novobiocin-resistant and coagulase negative . Phylogenetically, strain LCHXa belongs to the species . Strain LCHXa grew optimally in LB medium at pH 6-8 and 37 °C, and it was able to sustain growth at molar Li concentrations at 2 M LiCl, with a decrease in the specific growth rate of 85%. Osmoregulation in strain LCHXa partially involves glycine betaine and glycerol as compatible solutes.
PubMed: 32380652
DOI: 10.3390/microorganisms8050668 -
MSystems Aug 2021Methicillin-resistant Staphylococcus sciuri (MRSS) strain C2865 from a stranded dog in Nigeria was trimethoprim (TMP) resistant but lacked formerly described...
Methicillin-resistant Staphylococcus sciuri (MRSS) strain C2865 from a stranded dog in Nigeria was trimethoprim (TMP) resistant but lacked formerly described staphylococcal TMP-resistant dihydrofolate reductase genes (). Whole-genome sequencing, comparative genomics, and pan-genome analyses were pursued to unveil the molecular bases for TMP resistance via resistome and mobilome profiling. MRSS C2865 comprised a species subcluster and positioned just above the intraspecies boundary. Lack of species host tropism was observed. S. sciuri exhibited an open pan-genome, while MRSS C2865 harbored the highest number of unique genes (75% associated with mobilome). Within this fraction, we discovered a transferable TMP resistance gene, named , which confers high-level TMP resistance in Staphylococcus aureus and Escherichia coli. was located in a novel multidrug resistance mosaic plasmid (pUR2865-34) encompassing adaptive, mobilization, and segregational stability traits. was formerly denoted as in spp. from fish farm sediment in China but escaped identification in one macrococcal and diverse staphylococcal genomes in different Asian countries. shares the highest identity with of soil-related Paenibacillus anaericanus (68%). Data analysis discloses that has emerged from a single ancestor and places S. sciuri as a plausible donor. C2865 unique fraction additionally enclosed novel chromosomal mobile islands, including a multidrug-resistant pseudo-SCC cassette, three apparently functional prophages (), and an SaPI4-related staphylococcal pathogenicity island. Since seems not yet common in staphylococcal clinical specimens, our data promote early surveillance and enable molecular diagnosis. We evidence the genome plasticity of S. sciuri and highlight its role as a resourceful reservoir for adaptive traits. The discovery and surveillance of antimicrobial resistance genes (AMRG) and their mobilization platforms are critical to understand the evolution of bacterial resistance and to restrain further expansion. Limited genomic data are available on Staphylococcus sciuri; regardless, it is considered a reservoir for critical AMRG and mobile elements. We uncover a transferable staphylococcal TMP resistance gene, named , in a novel mosaic plasmid harboring additional resistance, adaptive, and self-stabilization features. is present but evaded detection in diverse species from varied sources geographically distant. Our analyses evidence that the -carrying element has emerged from a single ancestor and position S. sciuri as the donor species for spread. We also identify novel mobilizable chromosomal islands encompassing AMRG and three unrelated prophages. We prove high intraspecies heterogenicity and genome plasticity for S. sciuri. This work highlights the importance of genome-wide ecological studies to facilitate identification, characterization, and evolution routes of bacteria adaptive features.
PubMed: 34374564
DOI: 10.1128/mSystems.00511-21 -
Journal of Global Antimicrobial... Dec 2022In this study, we aimed to assess the extent of dissemination of methicillin-resistant Mammaliicoccus sciuri in animal farms in Tunisia and evaluate the distribution of...
OBJECTIVES
In this study, we aimed to assess the extent of dissemination of methicillin-resistant Mammaliicoccus sciuri in animal farms in Tunisia and evaluate the distribution of virulence and methicillin resistance genes in the M. sciuri population.
METHODS
Staphylococci and mammaliicocci isolated from unhealthy animals and healthy humans from adjacent farms in Tunisia were characterized for antimicrobial susceptibility, biofilm formation, agglutination, and hemolysis abilities. Mammaliicoccus sciuri relatedness and content in antibiotic resistance and virulence genes were analyzed by whole-genome sequencing (WGS).
RESULTS
Mammaliicoccus sciuri was the most prevalent species (46.2%), showing the highest resistance rates to fusidic acid (94.6%), oxacillin (73%), penicillin (40.5%), clindamycin (37%), ciprofloxacin (27%), and cefoxitin (24.3%). Some isolates carried genes encoding resistance to nine different antibiotic classes. mecA was found in 35% of M. sciuri and mecC in 16.2%. All isolates carrying mecC were of S. sciuri subspecies carnaticus and carried the hybrid element SCCmec-mecC. Mammaliicoccus sciuri were able to produce strong biofilm (27%) and have clumping ability (16%). Additionally, they carried genes for capsule production (cap8, 100%), iron-regulated surface determinants (isdE, 24%; isdG, 3%), and virulence regulation (clpC and clpP, 100%). Single nucleotide polymorphisms (SNPs) analysis showed that 17 M. sciuri cross-transmission events probably occurred between different animal species and farms. Moreover, SCCmec was estimated to have been acquired five times by S. sciuri subsp. carnaticus.
CONCLUSION
Multidrug resistant and pathogenic M. sciuri were frequently disseminated between different animal species within the farm environment. mecA and mecC can be disseminated by both frequent acquisition of the SCCmec element and clonal dissemination.
Topics: Animals; Humans; Methicillin Resistance; Animals, Domestic; Tunisia; Staphylococcus
PubMed: 36202202
DOI: 10.1016/j.jgar.2022.09.007 -
Veterinary World Sep 2022Coagulase-negative staphylococci (CNS) are becoming the major cause of clinical and subclinical bovine mastitis around the world. This study aims to estimate the...
BACKGROUND AND AIM
Coagulase-negative staphylococci (CNS) are becoming the major cause of clinical and subclinical bovine mastitis around the world. This study aims to estimate the prevalence, antibiogram, and frequency of the methicillin-resistant (MR) () gene in CNS collected from cows with subclinical mastitis.
MATERIALS AND METHODS
Thirty-four milk samples were collected from 20 cows. Fifteen subclinical mastitis samples (~44.12%) were identified as CNS isolates. The Vitek2 compact system method was employed for the identification of the species. Furthermore, antibiotic sensitivity tests were performed against 10 different antibiotics for CNS strains. The gene from isolated CNS was detected by conventional polymerase chain reaction (PCR).
RESULTS
was the most predominant isolated species with an incidence of 33.3% (5/15 isolates), followed by 26.7% for and (4/15 isolates), and 13.3% for (2/15 isolates), respectively. The highest resistance rates were determined to be 40% (6/15 isolates) against penicillin and oxacillin (OX), 33.3% (5/15 isolates) against clindamycin, 13% (2/15 isolates) against chloramphenicol, amoxicillin, and erythromycin, and 5% (1/15 isolates) against ciprofloxacin, respectively. The results revealed that the isolates were resistant to one or more antimicrobial agents, with five isolates displaying multiple antimicrobial resistance. Furthermore, the results exhibit that all CNS isolates had the gene at 310 bp with a 100% frequency. Moreover, for detecting MR isolates, there are significant discrepancies between phenotypic and genotypic approaches, and only 6/15 CNS isolates phenotypically demonstrated OX resistance.
CONCLUSION
The results emphasize the necessity of frequent monitoring of phenotypic and genotypic profiles of CNS isolates to ensure effective control measures and the prevention of multidrug resistance strain evolution.
PubMed: 36341061
DOI: 10.14202/vetworld.2022.2186-2191 -
Journal of Dairy Science Aug 2018The role of non-aureus staphylococci (NAS) in the risk of acquisition of intramammary infections with Staphylococcus aureus is vague and still under debate. The...
The role of non-aureus staphylococci (NAS) in the risk of acquisition of intramammary infections with Staphylococcus aureus is vague and still under debate. The objectives of this study were to (1) investigate the distribution patterns of NAS species from milk and teat skin in dairy herds with automatic milking systems, and (2) examine if the isolated NAS influences the expression of S. aureus virulence factors controlled by the accessory gene regulator (agr) quorum sensing system. In 8 herds, 14 to 20 cows with elevated somatic cell count were randomly selected for teat skin swabbing and aseptic quarter foremilk samples from right hind and left front quarters. Teat skin swabs were collected using the modified wet-dry method and milk samples were taken aseptically for bacterial culture. Colonies from quarters with suspicion of having NAS in milk or teat skin samples (or both) were subjected to MALDI-TOF assay for species identification. To investigate the interaction between S. aureus and NAS, 81 isolates NAS were subjected to a qualitative β-galactosidase reporter plate assay. In total, 373 NAS isolates were identified representing 105 from milk and 268 from teat skin of 284 quarters (= 142 cows). Sixteen different NAS species were identified, 15 species from teat skin and 10 species from milk. The most prevalent NAS species identified from milk were Staphylococcus epidermidis (50%), Staphylococcus haemolyticus (15%), and Staphylococcus chromogenes (11%), accounting for 76%. Meanwhile, the most prevalent NAS species from teat skin were Staphylococcus equorum (43%), S. haemolyticus (16%), and Staphylococcus cohnii (14%), accounting for 73%. Using reporter gene fusions monitoring transcriptional activity of key virulence factors and regulators, we found that out of 81 supernatants of NAS isolates, 77% reduced expression of hla, encoding a-hemolysin, 70% reduced expression of RNAIII, the key effector molecule of agr, and 61% reduced expression of spa encoding protein A of S. aureus, respectively. Our NAS isolates showed 3 main patterns: (1) downregulation effect such as S. chromogenes (milk) and Staphylococcus xylosus (milk and teat), (2) no effect such as Staphylococcus sciuri (teat) and S. vitulinus (teat), and the third pattern (c) variable effect such as S. epidermidis (milk and teat) and S. equorum (milk and teat). The pattern of cross-talk between NAS species and S. aureus virulence genes varied according to the involved NAS species, habitat type, and herd factors. The knowledge of how NAS influences S. aureus virulence factor expression could explain the varying protective effect of NAS on S. aureus intramammary infections.
Topics: Animals; Cattle; Female; Mammary Glands, Animal; Mastitis, Bovine; Milk; Staphylococcal Infections; Staphylococcus; Staphylococcus aureus
PubMed: 29778469
DOI: 10.3168/jds.2017-14311 -
Journal of Enzyme Inhibition and... Dec 2022A β-carbonic anhydrase (CA, EC 4.2.1.1) previously annotated to be present in the genome of , SauBCA, has been shown to belong to another pathogenic bacterium, . This...
A β-carbonic anhydrase (CA, EC 4.2.1.1) previously annotated to be present in the genome of , SauBCA, has been shown to belong to another pathogenic bacterium, . This enzyme, MscCA, has been investigated for its activation with a series of natural and synthetic amino acid and amines, comparing the results with those obtained for the ortholog enzyme from , EcoCAβ. The best MscCA activators were D-His, L- and D-DOPA, 4-(2-aminoethyl)-morpholine and L-Asn, which showed Ks of 0.12 - 0.89 µM. The least efficient activators were D-Tyr and L-Gln (Ks of 13.9 - 28.6 µM). The enzyme was also also inhibited by anions and sulphonamides, as described earlier. Endogenous CA activators may play a role in bacterial virulence and colonisation of the host which makes this research topic of great interest.
Topics: Amines; Amino Acids; Carbonic Anhydrases; Dihydroxyphenylalanine; Molecular Structure; Morpholines; Staphylococcus aureus; Sulfonamides
PubMed: 36210544
DOI: 10.1080/14756366.2022.2131780 -
The Onderstepoort Journal of Veterinary... Nov 2021Staphylococcus species colonises humans and animals and is a major food contaminant with public health significance. Here, we assessed the occurrence of...
Staphylococcus species colonises humans and animals and is a major food contaminant with public health significance. Here, we assessed the occurrence of methicillin-resistant staphylococci (MRS) in the pig-production chain in Ibadan, Nigeria. Nares of 120 pigs and 10 farmers were sampled with sterile swabs whilst 54 pork samples were collected from a retail slaughterhouse. Staphylococcus species were isolated using enrichment, cefoxitin-aztreonam selective broth and Mannitol salt agar. Isolates were tested for susceptibility to cefoxitin (30 μg), oxacillin (1 μg) and vancomycin (30 μg). Methicillin-resistant staphylococci isolates were characterised using conventional biochemical tests. From 184 samples, 364 staphylococcal isolates were obtained. Amongst the 54 pork samples, 44.0% were contaminated with Staphylococcus species. Overall, 9 (2.5%) MRS were obtained and presumptively identified as Staphylococcus xylosus (n = 3), Staphylococcus sciuri (n = 3), Staphylococcus warneri (n = 2) and Staphylococcus cohnii (n = 1). There was no relationship between the prevalence of MRS between pigs and pig handlers in the farms, but Farm 2 had the highest frequency of 66.7% (p 0.05). Piglets had the highest prevalence of 66.7% (p 0.05) whilst MRS was absent in workers and pork samples. This study raises concerns about the cross-contamination of staphylococci in the food chain. Constant surveillance is imperative to ensure food safety.
Topics: Animals; Anti-Bacterial Agents; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Nigeria; Staphylococcal Infections; Staphylococcus; Swine; Swine Diseases
PubMed: 34879684
DOI: 10.4102/ojvr.v88i1.1959 -
PloS One 2017There has been a paucity of data on methicillin-resistant Staphylococcus sciuri (MRSS) epidemiology in European healthcare settings. The aim of the study was to...
There has been a paucity of data on methicillin-resistant Staphylococcus sciuri (MRSS) epidemiology in European healthcare settings. The aim of the study was to determine the prevalence of nasal and pharyngeal carriage and diversity of MRSS among inpatients and healthcare workers (HCWs) in the largest healthcare centre in Serbia, and to assess performance of different methods for MRSS screening. Nasal and pharyngeal swabs were obtained from 195 patients and 105 HCWs in different departments. Each swab was inoculated directly onto MRSA-ID, oxacillin-resistance screening agar and mannitol salt agar (MSA) with 2 mg/L of oxacillin. After inoculation, each swab was dipped in Mueller-Hinton broth with 6.5% NaCl and after overnight incubation, subcultured onto oxacillin-MSA. Characterisation of isolated MRSS strains was determined by antimicrobial susceptibility testing, PFGE, SCCmec typing and antimicrobial resistance genes detection. MRSS nasal and pharyngeal carriage rate was high (5%) in our hospital and department-variable. PFGE revealed a possible cross-transmission of MRSS between a patient and an HCW, and dissemination across hospital wards. All analysed isolates were multidrug resistant. Fusidic acid resistance was discovered in 93.7% of isolates, but fusA mutations in EF-G and fusB/C genes were not detected. SCCmec regions of MRSS contained elements of classic methicillin-resistant S. aureus type III. Broth enrichment prior to isolation on oxacillin-MSA was superior to direct cultivation on different media with a sensitivity/specificity of 100% and 88.5%, respectively. MRSS is a significant coloniser of patients and HCWs in the hospital. Further research is needed to investigate the clinical significance of the bacterium in our settings.
Topics: Adult; Aged; Aged, 80 and over; Bacterial Proteins; Carrier State; Health Personnel; Hospitals, University; Humans; Methicillin Resistance; Microbial Sensitivity Tests; Middle Aged; Nasal Cavity; Oxacillin; Pharynx; Serbia; Staphylococcal Infections; Staphylococcus; Young Adult
PubMed: 28926634
DOI: 10.1371/journal.pone.0185181