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    Genotyping of methicillin resistant Staphylococcus aureus from the United Arab Emirates
    ([London] : Macmillan Publishers Limited, part of Springer Nature, 2020) Senok, Abiola; Nassar, Rania; Celiloglu, Handan; Nabi, Anju; Alfaresi, Mubarak; Weber, Stefan; Rizvi, Irfan; Müller, Elke; Reissig, Annett; Gawlik, Darius; Monecke, Stefan; Ehricht, Ralf
    Reports from Arabian Gulf countries have demonstrated emergence of novel methicillin resistant Staphylococcus aureus (MRSA) strains. To address the lack of data from the United Arab Emirates (UAE), genetic characterisation of MRSA identified between December 2017 and August 2019 was conducted using DNA microarray-based assays. The 625 MRSA isolates studied were grouped into 23 clonal complexes (CCs) and assigned to 103 strains. CC5, CC6, CC22 and CC30 represented 54.2% (n/N = 339/625) of isolates with other common CCs being CC1, CC8, CC772, CC361, CC80, CC88. Emergence of CC398 MRSA, CC5-MRSA-IV Sri Lanka Clone and ST5/ST225-MRSA-II, Rhine-Hesse EMRSA/New York-Japan Clone in our setting was detected. Variants of pandemic CC8-MRSA-[IVa + ACME I] (PVL+) USA300 were detected and majority of CC772 strains were CC772-MRSA-V (PVL+), “Bengal- Bay Clone”. Novel MRSA strains identified include CC5-MRSA-V (edinA+), CC5-MRSA-[VT + fusC], CC5-MRSA-IVa (tst1+), CC5-MRSA-[V/VT + cas + fusC + ccrA/B-1], CC8-MRSA-V/VT, CC22-MRSA-[IV + fusC + ccrAA/(C)], CC45-MRSA-[IV + fusC + tir], CC80-MRSA-IVa, CC121-MRSA-V/VT, CC152-MRSA-[V + fusC] (PVL+). Although several strains harboured SCC-borne fusidic acid resistance (fusC) (n = 181), erythromycin/clindamycin resistance (ermC) (n = 132) and gentamicin resistance (aacA-aphD) (n = 179) genes, none harboured vancomycin resistance genes while mupirocin resistance gene mupR (n = 2) and cfr gene (n = 1) were rare. An extensive MRSA repertoire including CCs previously unreported in the region and novel strains which probably arose locally suggest an evolving MRSA landscape. © 2020, The Author(s).
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    Molecular investigations on a chimeric strain of Staphylococcus aureus sequence type 80
    (San Francisco, California, US : PLOS, 2020) Gawlik, Darius; Ruppelt-Lorz, Antje; Müller, Elke; Reißig, Annett; Hotzel, Helmut; Braun, Sascha D.; Söderquist, Bo; Ziegler-Cordts, Albrecht; Stein, Claudia; Pletz, Mathias W.; Ehricht, Ralf; Monecke, Stefan
    A PVL-positive, methicillin-susceptible Staphylococcus aureus was cultured from pus from cervical lymphadenitis of a patient of East-African origin. Microarray hybridisation assigned the isolate to clonal complex (CC) 80 but revealed unusual features, including the presence of the ORF-CM14 enterotoxin homologue and of an ACME-III element as well as the absence of etD and edinB. The isolate was subjected to both, Illumina and Nanopore sequencing allowing characterisation of deviating regions within the strain´s genome. Atypical features of this strain were attributable to the presence of two genomic regions that originated from other S. aureus lineages and that comprised, respectively, 3% and 1.4% of the genome. One deviating region extended from walJ to sirB. It comprised ORF-CM14 and the ACME-III element. A homologous but larger fragment was also found in an atypical S. aureus CC1/ST567 strain whose lineage might have served as donor of this genomic region. This region itself is a chimera comprising fragments from CC1 as well as fragments of unknown origin. The other deviating region comprised the region from htsB to ecfA2, i.e., another 3% of the genome. It was very similar to CC1 sequences. Either this suggests an incorporation of CC1 DNA into the study strain, or alternatively a recombination event affecting “canonical” CC80. Thus, the study strain bears witness of several recombination events affecting supposedly core genomic genes. Although the exact mechanism is not yet clear, such chimerism seems to be an additional pathway in the evolution of S. aureus. This could facilitate also a transmission of virulence and resistance factors and therefore offer an additional evolutionary advantage.
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    Phenotypic and Molecular Detection of Biofilm Formation in Staphylococcus aureus Isolated from Different Sources in Algeria
    (Basel : MDPI, 2020) Achek, Rachid; Hotzel, Helmut; Nabi, Ibrahim; Kechida, Souad; Mami, Djamila; Didouh, Nassima; Tomaso, Herbert; Neubauer, Heinrich; Ehricht, Ralf; Monecke, Stefan; El-Adawy, Hosny
    Staphylococcus aureus is an opportunistic bacterium causing a wide variety of diseases. Biofilm formation of Staphylococcus aureus is of primary public and animal health concern. The purposes of the present study were to investigate the ability of Staphylococcus aureus isolated from animals, humans, and food samples to form biofilms and to screen for the presence of biofilmassociated and regulatory genes. In total, 55 Staphylococcus aureus isolated from sheep mastitis cases (n = 28), humans (n = 19), and from food matrices (n = 8) were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The ability of Staphylococcus aureus for slime production and biofilm formation was determined quantitatively. A DNA microarray examination was performed to detect adhesion genes (icaACD and biofilmassociated protein gene (bap)), genes encoding microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), regulatory genes (accessory gene regulator (agr) and staphylococcal accessory regulator (sarA)), and the staphylococcal cassette chromosome mec elements (SCCmec). Out of 55 Staphylococcus aureus isolates, 39 (71.0%) and 23 (41.8%) were producing slime and biofilm, respectively. All Staphylococcus aureus strains isolated from food showed biofilm formation ability. 52.6% of the Staphylococcus aureus strains isolated from sheep with mastitis, and 17.9% of isolates from humans, were able to form a biofilm. Microarray analysis typed the Staphylococcus aureus into 15 clonal complexes. Among all Staphylococcus aureus isolates, four of the human isolates (21.1%) harbored the mecA gene (SCCmec type IV) typed into 2 clonal complexes (CC22-MRSA-IV and CC80-MRSA-IV) and were considered as methicillin-resistant, while two of them were slime-producing. None of the isolates from sheep with mastitis harbored the cna gene which is associated with biofilm production. The fnbB gene was found in 100%, 60% and 40% of biofilm-producing Staphylococcus aureus isolated from food, humans, and sheep with mastitis, respectively. Three agr groups were present and agr group III was predominant with 43.6%, followed by agr group I (38.2%), and agr group II (18.2%). This study revealed the capacity of Staphylococcus aureus isolates to form biofilms and highlighted the genetic background displayed by Staphylococcus aureus isolates from different sources in Algeria. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
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    Shared MRSA Strains among Nepalese Rhesus macaques (Macaca mulatta), their Environment and Hospitalized Patients
    (Lausanne : Frontiers Media, 2019) Roberts, Marilyn C.; Joshi, Prabhu Raj; Monecke, Stefan; Ehricht, Ralf; Müller, Elke; Gawlik, Darius; Paudel, Saroj; Acharya, Mahesh; Bhattarai, Sankalpa; Pokharel, Sujana; Tuladhar, Reshma; Chalise, Mukesh K.; Kyes, Randall C.
    This study looked at 227 saliva samples from Rhesus macaques (Macaca mulatta) and 218 samples from the surrounding environments. From these samples, MRSA isolates were collected from Rhesus saliva samples (n = 13) and environmental samples (n = 19) near temple areas in Kathmandu, Nepal. For comparison, selected MRSA isolates (n = 5) were obtained from patients with wound infections from a Kathmandu hospital. All isolates were characterized using Abbott StaphyType® DNA microarrays. Eighteen isolates (62%) from monkeys (n = 4; 31%) and environmental samples (n = 14; 74%), were CC22-MRSA-IV. Most (n = 16) of them carried both, the PVL locus and toxic shock toxin gene (tst1), an unusual combination which is the same as in previously characterized strain from Nepalese macaques and pigs. The five human isolates also belonged to that strain type. Eight monkey MRSA isolates were CC361-MRSA-IV. One MRSA from a monkey and one from an environmental sample, were CC88-MRSA-V. Other environmental MRSA included one each, CC121-MRSA-VT, and CC772 -MRSA-V. Two were CC779-MRSA-VT, potentially a novel clone. All MRSA carried the blaZ gene. The aacA–aphD, dfrA, and erm (C) genes were very common in isolates from all sources. One macaque MRSA carried the resistance genes aphA3 and sat, neither previously identified in primate MRSA isolates. This current study suggests that humans could be a potential source of the MRSA in the macaques/environment and transmission may be linked to humans feeding the primates and/or living in close proximity to each other.This study looked at 227 saliva samples from Rhesus macaques (Macaca mulatta) and 218 samples from the surrounding environments. From these samples, MRSA isolates were collected from Rhesus saliva samples (n = 13) and environmental samples (n = 19) near temple areas in Kathmandu, Nepal. For comparison, selected MRSA isolates (n = 5) were obtained from patients with wound infections from a Kathmandu hospital. All isolates were characterized using Abbott StaphyType® DNA microarrays. Eighteen isolates (62%) from monkeys (n = 4; 31%) and environmental samples (n = 14; 74%), were CC22-MRSA-IV. Most (n = 16) of them carried both, the PVL locus and toxic shock toxin gene (tst1), an unusual combination which is the same as in previously characterized strain from Nepalese macaques and pigs. The five human isolates also belonged to that strain type. Eight monkey MRSA isolates were CC361-MRSA-IV. One MRSA from a monkey and one from an environmental sample, were CC88-MRSA-V. Other environmental MRSA included one each, CC121-MRSA-VT, and CC772 -MRSA-V. Two were CC779-MRSA-VT, potentially a novel clone. All MRSA carried the blaZ gene. The aacA–aphD, dfrA, and erm (C) genes were very common in isolates from all sources. One macaque MRSA carried the resistance genes aphA3 and sat, neither previously identified in primate MRSA isolates. This current study suggests that humans could be a potential source of the MRSA in the macaques/environment and transmission may be linked to humans feeding the primates and/or living in close proximity to each other.
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    Characterisation of a novel composite SCCmec-SCCfus element in an emerging Staphylococcus aureus strain from the Arabian Gulf region
    (San Francisco : Public Library of Science, 2019) Senok, Abiola; Slickers, Peter; Hotzel, Helmut; Boswihi, Samar; Braun, Sascha D.; Gawlik, Darius; Müller, Elke; Nabi, Anju; Nassar, Rania; Nitschke, Hedda; Reißig, Annett; Ruppelt-Lorz, Antje; Mafofo, Joseph; Somili, Ali M.; Udo, Edet; Ehricht, Ralf; Monecke, Stefan
    Fusidic acid is a steroid antibiotic known since the 1960s. It is frequently used in topical preparations, i.e., ointments, for the treatment of skin and soft tissue infections caused by Staphylococcus aureus. There is an increasing number of methicillin-resistant S. aureus (MRSA) strains that harbour plasmid-borne fusB/far1 or fusC that is localised on SCC elements. In this study we examined a series of related CC30-MRSA isolates from the Arabian Gulf countries that presented with SCCmec elements and fusC, including a variant that—to the best of our knowledge—has not yet formally been described. It consisted of a class B mec complex and ccrA/B-4 genes. The fusidic acid resistance gene fusC was present, but contrary to the previously sequenced element of HDE288, it was not accompanied by tirS. This element was identified in CC30 MRSA from Kuwait, Saudi Arabia and the United Arab Emirates that usually also harbour the Panton-Valentin leukocidin (PVL) genes. It was also identified in CC8 and ST834 isolates. In addition, further CC30 MRSA strains with other SCCmec VI elements harbouring fusC were found to circulate in the Arabian Gulf region. It can be assumed that MRSA strains with SCCmec elements that include fusC have a selective advantage in both hospital and community settings warranting a review of the use of topical antibiotics and indicating the necessity of reducing over-the-counter sale of antibiotics, including fusidic acid, without prescription.Fusidic acid is a steroid antibiotic known since the 1960s. It is frequently used in topical preparations, i.e., ointments, for the treatment of skin and soft tissue infections caused by Staphylococcus aureus. There is an increasing number of methicillin-resistant S. aureus (MRSA) strains that harbour plasmid-borne fusB/far1 or fusC that is localised on SCC elements. In this study we examined a series of related CC30-MRSA isolates from the Arabian Gulf countries that presented with SCCmec elements and fusC, including a variant that—to the best of our knowledge—has not yet formally been described. It consisted of a class B mec complex and ccrA/B-4 genes. The fusidic acid resistance gene fusC was present, but contrary to the previously sequenced element of HDE288, it was not accompanied by tirS. This element was identified in CC30 MRSA from Kuwait, Saudi Arabia and the United Arab Emirates that usually also harbour the Panton-Valentin leukocidin (PVL) genes. It was also identified in CC8 and ST834 isolates. In addition, further CC30 MRSA strains with other SCCmec VI elements harbouring fusC were found to circulate in the Arabian Gulf region. It can be assumed that MRSA strains with SCCmec elements that include fusC have a selective advantage in both hospital and community settings warranting a review of the use of topical antibiotics and indicating the necessity of reducing over-the-counter sale of antibiotics, including fusidic acid, without prescription.
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    Fast, economic and simultaneous identification of clinically relevant Gram-negative species with multiplex real-time PCR
    (London : Future Medicine Ltd, 2019) Weiss, Daniel; Gawlik, Darius; Hotzel, Helmut; Engelmann, Ines; Mueller, Elke; Slickers, Peter; Braun, Sascha D.; Monecke, Stefan; Ehricht, Ralf
    Aim: A newly designed multiplex real-time PCR (rt-PCR) was validated to detect four clinically relevant Gram-negative bacteria (Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa). Materials & methods: Serial dilutions of genomic DNA were used to determine the limit of detection. Colony PCR was performed with isolates of the four selected species and other species as negative controls. Isolates were characterized genotypically and phenotypically to evaluate the assay. Results: Specific signals of all target genes were detected with diluted templates comprising ten genomic equivalents. Using colony rt-PCR, all isolates of the target species were identified correctly. All negative control isolates were negative. Conclusion: The genes gad, basC, khe and ecfX can reliably identify these four species via multiplex colony rt-PCR. © 2018 Daniel Weiss.
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    Evolution and Global Transmission of a Multidrug-Resistant, Community-Associated Methicillin-Resistant Staphylococcus aureus Lineage from the Indian Subcontinent
    (Washington D.C. : American Society for Microbiology, 2019) Steinig, Eike J.; Duchene, Sebastian; Robinson, D. Ashley; Monecke, Stefan; Yokoyama, Maho; Laabei, Maisem; Slickers, Peter; Andersson, Patiyan; Williamson, Deborah; Kearns, Angela; Goering, Richard V.; Dickson, Elizabeth; Ehricht, Ralf; Ip, Margaret; O'Sullivan, Matthew V.N.; Coombs, Geoffrey; Petersen, Andreas; Brennan, Gráinne I.; Shore, Anna C.; Coleman, David C.; Pantosti, Annalisa; de Lencastre, Herminia; Westh, Henrik; Kobayashi, Nobumichi; Heffernan, Helen; Strommenger, Birgit; Layer, Franziska; Weber, Stefan; Aamot, Hege Vangstein; Skakni, Leila; Peacock, Sharon J.; Sarovich, Derek; Harris, Simon; Parkhill, Julian; Massey, Ruth C.; Holden, Mathew T.G.; Bentley, Stephen; Tong, Stephen Y.C.
    The evolution and global transmission of antimicrobial resistance have been well documented for Gram-negative bacteria and health care-associated epidemic pathogens, often emerging from regions with heavy antimicrobial use. However, the degree to which similar processes occur with Gram-positive bacteria in the community setting is less well understood. In this study, we traced the recent origins and global spread of a multidrug-resistant, community-associated Staphylococcus aureus lineage from the Indian subcontinent, the Bengal Bay clone (ST772). We generated whole-genome sequence data of 340 isolates from 14 countries, including the first isolates from Bangladesh and India, to reconstruct the evolutionary history and genomic epidemiology of the lineage. Our data show that the clone emerged on the Indian subcontinent in the early 1960s and disseminated rapidly in the 1990s. Short-term outbreaks in community and health care settings occurred following intercontinental transmission, typically associated with travel and family contacts on the subcontinent, but ongoing endemic transmission was uncommon. Acquisition of a multidrug resistance integrated plasmid was instrumental in the emergence of a single dominant and globally disseminated clade in the early 1990s. Phenotypic data on biofilm, growth, and toxicity point to antimicrobial resistance as the driving force in the evolution of ST772. The Bengal Bay clone therefore combines the multidrug resistance of traditional health care-associated clones with the epidemiological transmission of community-associated methicillin-resistant S. aureus (MRSA). Our study demonstrates the importance of whole-genome sequencing for tracking the evolution of emerging and resistant pathogens. It provides a critical framework for ongoing surveillance of the clone on the Indian subcontinent and elsewhere.
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    Characteristics of methicillin-resistant Staphylococcus aureus from broiler farms in Germany are rather lineage- than source-specific
    (Oxford ; Cary, NC : Oxford University Press, 2019) Kittler, Sophie; Seinige, Diana; Meemken, Diana; Müller, Anja; Wendlandt, Sarah; Ehricht, Ralf; Monecke, Stefan; Kehrenberg, Corinna
    Methicillin-resistant Staphylococcus aureus (MRSA) are a major concern for public health, and broiler farms are a potential source of MRSA isolates. In this study, a total of 56 MRSA isolates from 15 broiler farms from 4 different counties in Germany were characterised phenotypically and genotypically. Spa types, dru types, SCCmec types, and virulence genes as well as resistance genes were determined by using a DNA microarray or specific PCR assays. In addition, PFGE profiles of isolates were used for analysis of their epidemiological relatedness. While half of the isolates belonged to spa type t011, the other half was of spa types t1430 and t034. On 3 farms, more than 1 spa type was found. The most common dru type was dt10a (n = 19), followed by dt11a (n = 17). Susceptibility testing of all isolates by broth microdilution revealed 21 different resistance phenotypes and a wide range of resistance genes was present among the isolates. Up to 10 different resistance phenotypes were found on individual farms. Resistance to tetracyclines (n = 53), MLSB antibiotics (n = 49), trimethoprim (n = 38), and elevated MICs of tiamulin (n = 29) were most commonly observed. Microarray analysis detected genes for leucocidin (lukF/S), haemolysin gamma (hlgA), and other haemolysines in all isolates. In all t1430 isolates, the egc cluster comprising of genes encoding enterotoxin G, I, M, N, O, U, and/or Y was found. The splitstree analysis based on microarray and PCR gene profiles revealed that all CC9/SCCmec IV/t1430/dt10a isolates clustered apart from the other isolates. These findings confirm that genotypic patterns were specific for clonal lineages rather than for the origin of isolates from individual farms.
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    Phylodynamic signatures in the emergence of community-associated MRSA
    (Washington, DC : National Acad. of Sciences, 2022) Steinig, Eike; Aglua, Izzard; Duchene, Sebastian; Meehan, Michael T.; Yoannes, Mition; Firth, Cadhla; Jaworski, Jan; Drekore, Jimmy; Urakoko, Bohu; Poka, Harry; Wurr, Clive; Ebos, Eri; Nangen, David; Müller, Elke; Mulvey, Peter; Jackson, Charlene; Blomfeldt, Anita; Aamot, Hege Vangstein; Laman, Moses; Manning, Laurens; Earls, Megan; Coleman, David C.; Greenhill, Andrew; Ford, Rebecca; Stegger, Marc; Syed, Muhammad Ali; Jamil, Bushra; Monecke, Stefan; Ehricht, Ralf; Smith, Simon; Pomat, William; Horwood, Paul; Tong, Steven Y. C.; McBryde, Emma
    Community-associated, methicillin-resistant Staphylococcus aureus (MRSA) lineages have emerged in many geographically distinct regions around the world during the past 30 y. Here, we apply consistent phylodynamic methods across multiple community-associated MRSA lineages to describe and contrast their patterns of emergence and dissemination. We generated whole-genome sequencing data for the Australian sequence type (ST) ST93-MRSA-IV from remote communities in Far North Queensland and Papua New Guinea, and the Bengal Bay ST772-MRSA-V clone from metropolitan communities in Pakistan. Increases in the effective reproduction number (Re) and sustained transmission (Re > 1) coincided with spread of progenitor methicillin-susceptible S. aureus (MSSA) in remote northern Australian populations, dissemination of the ST93-MRSA-IV genotype into population centers on the Australian East Coast, and subsequent importation into the highlands of Papua New Guinea and Far North Queensland. Applying the same phylodynamic methods to existing lineage datasets, we identified common signatures of epidemic growth in the emergence and epidemiological trajectory of community-associated S. aureus lineages from America, Asia, Australasia, and Europe. Surges in Re were observed at the divergence of antibiotic-resistant strains, coinciding with their establishment in regional population centers. Epidemic growth was also observed among drug-resistant MSSA clades in Africa and northern Australia. Our data suggest that the emergence of community-associated MRSA in the late 20th century was driven by a combination of antibiotic-resistant genotypes and host epidemiology, leading to abrupt changes in lineage-wide transmission dynamics and sustained transmission in regional population centers.
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    Presence of β-Lactamase-producing Enterobacterales and Salmonella Isolates in Marine Mammals
    (Basel : Molecular Diversity Preservation International (MDPI), 2021) Grünzweil, Olivia M.; Palmer, Lauren; Cabal, Adriana; Szostak, Michael P.; Ruppitsch, Werner; Kornschober, Christian; Korus, Maciej; Misic, Dusan; Bernreiter-Hofer, Tanja; Korath, Anna D. J.; Feßler, Andrea T.; Allerberger, Franz; Schwarz, Stefan; Spergser, Joachim; Müller, Elke; Braun, Sascha D.; Monecke, Stefan; Ehricht, Ralf; Walzer, Chris; Smodlaka, Hrvoje; Loncaric, Igor
    Marine mammals have been described as sentinels of the health of marine ecosystems. Therefore, the aim of this study was to investigate (i) the presence of extended-spectrum β-lactamase (ESBL)- and AmpC-producing Enterobacterales, which comprise several bacterial families important to the healthcare sector, as well as (ii) the presence of Salmonella in these coastal animals. The antimicrobial resistance pheno- and genotypes, as well as biocide susceptibility of Enterobacterales isolated from stranded marine mammals, were determined prior to their rehabilitation. All E. coli isolates (n = 27) were screened for virulence genes via DNA-based microarray, and twelve selected E. coli isolates were analyzed by whole-genome sequencing. Seventy-one percent of the Enterobacterales isolates exhibited a multidrug-resistant (MDR) pheno- and genotype. The gene blaCMY (n = 51) was the predominant β-lactamase gene. In addition, blaTEM-1 (n = 38), blaSHV-33 (n = 8), blaCTX-M-15 (n = 7), blaOXA-1 (n = 7), blaSHV-11 (n = 3), and blaDHA-1 (n = 2) were detected. The most prevalent non-β-lactamase genes were sul2 (n = 38), strA (n = 34), strB (n = 34), and tet(A) (n = 34). Escherichia coli isolates belonging to the pandemic sequence types (STs) ST38, ST167, and ST648 were identified. Among Salmonella isolates (n = 18), S. Havana was the most prevalent serotype. The present study revealed a high prevalence of MDR bacteria and the presence of pandemic high-risk clones, both of which are indicators of anthropogenic antimicrobial pollution, in marine mammals.