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Francisco Soriano - One of the best experts on this subject based on the ideXlab platform.
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The bactericidal activities of HMR 3004, HMR 3647 and erythromycin against Gram-positive bacilli and development of resistance
The Journal of antimicrobial chemotherapy, 1999Co-Authors: Ricardo Fernández-roblas, R. Calvo, Jaime Esteban, André Bryskier, Francisco SorianoAbstract:The bactericidal activities of two new ketolides, HMR 3004 and HMR 3647, and the potential to develop resistance to these two antibiotics were studied in Gram-positive bacilli. As judged by time-kill kinetics both ketolides were mostly bacteriostatic, being bactericidal against only highly susceptible isolates of Corynebacterium striatum (two isolates) and Corynebacterium minutissimum (one isolate). Spontaneous resistant mutants were detected in seven of 30 strains tested, mainly in Rhodococcus equi, C. minutissimum and C. striatum, with a very low frequency of mutation (10 -12 -10 -15 ).
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In Vitro Susceptibilities of Aerobic and Facultative Non-Spore-Forming Gram-Positive Bacilli to HMR 3647 (RU 66647) and 14 Other Antimicrobials
Antimicrobial agents and chemotherapy, 1998Co-Authors: Francisco Soriano, Ricardo Fernández-roblas, R. Calvo, Gloria García-calvoAbstract:The comparative in vitro activity of the ketolide HMR 3647 (RU 66647) and those of structurally related macrolide-lincosamide-streptogramin compounds (erythromycin, roxithromycin, azithromycin, clarithromycin, josamycin, lincomycin, pristinamycin, and quinupristin-dalfopristin) as well as those of benzylpenicillin, doxycycline, vancomycin, teicoplanin, levofloxacin, and rifapentine against 247 aerobic and facultative non-spore-forming gram-positive bacilli were determined by an agar dilution method. The ketolide was active against most organisms tested except Corynebacterium striatum, coryneform CDC group 12, and Oerskovia spp. The frequency of resistance to erythromycin and other macrolides as well as that to lincomycin was high. Pristinamycin and, to a lesser extent, quinupristin-dalfopristin were very active, but resistance to these agents was present in some strains of Rhodococcus equi, Listeria spp., C. striatum, Erysipelothrix rhusiopathiae, and Oerskovia spp. HMR 3647 was very active against all erythromycin-sensitive and many erythromycin-nonsusceptible strains, especially Corynebacterium minutissimum, Corynebacterium pseudodiphtheriticum, Corynebacterium amycolatum, and Corynebacterium jeikeium. In vitro resistance to benzylpenicillin was common, but doxycycline, vancomycin, and teicoplanin were very active against most organisms tested except E. rhusiopathiae, against which glycopeptide antibiotics were not active. The in vitro activity of levofloxacin was remarkable, but resistance to this agent was common for C. amycolatum, Corynebacterium urealyticum, C. jeikeium, and Oerskovia spp. strains. Rifapentine was also very active in vitro against many organisms, but resistance to this agent was always present in E. rhusiopathiae and was very common in C. striatum and C. urealyticum.
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Antimicrobial susceptibilities of Corynebacterium species and other non-spore-forming gram-positive bacilli to 18 antimicrobial agents.
Antimicrobial Agents and Chemotherapy, 1995Co-Authors: Francisco Soriano, J. Zapardiel, E. NietoAbstract:The susceptibilities of 265 strains of Corynebacterium species and other non-spore-forming gram-positive bacilli to 18 antimicrobial agents were tested. Most strains were susceptible to vancomycin, doxycycline, and fusidic acid. Corynebacterium jeikeium and Corynebacterium urealyticum were the most resistant organisms tested. Resistance to beta-lactams, clindamycin, erythromycin, azythromycin, ciprofloxacin and gentamicin was common among strains of Corynebacterium xerosis and Corynebacterium minutissimum. Ampicillin resistance among Listeria monocytogenes was more prevalent than previously reported. Optochin, fosfomycin, and nitrofurantoin showed very little activity against most organisms tested, but the use of nitrofurantoin as a selective agent in culture medium may prevent the recovery of some isolates. Except for the unvarying activity of vancomycin against Corynebacterium species, the antimicrobial susceptibilities of the latter to other antibiotics are usually unpredictable, such that susceptibility tests are necessary for selecting the best antimicrobial treatment.
E. Nieto - One of the best experts on this subject based on the ideXlab platform.
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Antimicrobial susceptibilities of Corynebacterium species and other non-spore-forming gram-positive bacilli to 18 antimicrobial agents.
Antimicrobial Agents and Chemotherapy, 1995Co-Authors: Francisco Soriano, J. Zapardiel, E. NietoAbstract:The susceptibilities of 265 strains of Corynebacterium species and other non-spore-forming gram-positive bacilli to 18 antimicrobial agents were tested. Most strains were susceptible to vancomycin, doxycycline, and fusidic acid. Corynebacterium jeikeium and Corynebacterium urealyticum were the most resistant organisms tested. Resistance to beta-lactams, clindamycin, erythromycin, azythromycin, ciprofloxacin and gentamicin was common among strains of Corynebacterium xerosis and Corynebacterium minutissimum. Ampicillin resistance among Listeria monocytogenes was more prevalent than previously reported. Optochin, fosfomycin, and nitrofurantoin showed very little activity against most organisms tested, but the use of nitrofurantoin as a selective agent in culture medium may prevent the recovery of some isolates. Except for the unvarying activity of vancomycin against Corynebacterium species, the antimicrobial susceptibilities of the latter to other antibiotics are usually unpredictable, such that susceptibility tests are necessary for selecting the best antimicrobial treatment.
G. Wauters - One of the best experts on this subject based on the ideXlab platform.
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Corynebacterium simulans sp. nov., a non-lipophilic, fermentative Corynebacterium.
International Journal of Systematic and Evolutionary Microbiology, 2000Co-Authors: Pierre Wattiau, Michele Janssens, G. WautersAbstract:Three coryneform strains isolated from clinical samples were analysed. These strains fitted the biochemical profile of Corynebacterium striatum by conventional methods. However, according to recently described identification tests for fermenting corynebacteria, the strains behaved rather like Corynebacterium minutissimum. The three isolates could be distinguished from C. minutissimum by a positive nitrate and nitrite reductase test and by not fermenting maltose; from C. striatum by their inability to acidify ethylene glycol and to grow at 20 degrees C. Genetic studies based on 16S rRNA showed that the three strains were in fact different from C. minutissimum and C. striatum (96.9 and 98% similarity, respectively) and from other corynebacteria. They represent a new species for which the name Corynebacterium simulans sp. nov. is proposed. The type strain is DSM 44415T (= UCL 553T = Co 553T).
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Prospective Study of Catalase-positive Coryneform Organisms in Clinical Specimens: Identification, Clinical Relevance, and Antibiotic Susceptibility
Diagnostic microbiology and infectious disease, 1998Co-Authors: Katrien Lagrou, G. Wauters, Michele Janssens, Jacques Verhaegen, Ludo VerbistAbstract:During a 6-month period, all clinical isolates of catalase-positive coryneform organisms, which were isolated during the routine processing of clinical specimens, were characterized in the laboratory of the 1800-bed University Hospital of Leuven. The distribution of the species in the corynebacteria was: Corynebacterium amycolatum 70 (53%), Corynebacterium jeikeium 16 (12%), Corynebacterium striatum 11 (8%), Corynebacterium afermentans 10 (7%), Corynebacterium minutissimum 9 (6%), CDC coryneform group G 4 (3%), Corynebacterium urealyticum 4 (3%), Corynebacterium glucuronolyticum 1 (0.7%), and Corynebacterium xerosis 1 (0.7%). Of the 150 isolates, 37 (25%) were considered to be infection related and the remaining 113 (75%) were of questionable clinical significance. Susceptibility of the corynebacteria to 12 antibiotics active against Gram-positive organisms was evaluated. C. amycolatum, C. jeikeium, and C. urealyticum were multiresistant, but all isolates were susceptible to teicoplanin and vancomycin. Most of the C. amycolatum strains, and all strains of C. jeikeium and C. striatum, were susceptible to the vibriocidal compound O/129. (C) 1998 Elsevier Science Inc.
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propionic acid producing strains previously designated as Corynebacterium xerosis c minutissimum c striatum and cdc group i2 and group f2 coryneforms belong to the species Corynebacterium amycolatum
International Journal of Systematic and Evolutionary Microbiology, 1996Co-Authors: G. Wauters, A Driessen, Elisabeth Ageron, Michele Janssens, Pad GrimontAbstract:Propionic acid-producing Corynebacterium strains that lacked mycolic acids and were formerly identified as Corynebacterium minutissimum, Corynebacterium xerosis, Corynebacterium striatum, and CDC group I-2 and F-2 strains were studied to determine their relatedness to Corynebacterium amycolatum, A total of 60 strains were used for phenotypic characterization studies, and 26 of these strains were used for genetic studies, DNA-DNA hybridization experiments performed at 65 degrees C revealed that the levels of relatedness between the propionic acid-producing strains and the type strain of C. amycolatum were more than 70% and that the Delta T-m, values ranged from 0 to 5 degrees C (Delta T-m is the difference between the denaturation temperature of a homoduplex and the denaturation temperature of a heteroduplex); these values are consistent with inclusion of these strains in the species C. amycolatum, Currently used conventional tests, such as urease, nitrate reduction, and sugar fermentation tests, were not suitable for accurate identification of C. amycolatum, Phenotypic differentiation of this species from related taxa should be based on the following characteristics in addition to propionic acid production: lipid requirement, Tween esterase activity, tyrosine clearing, alkaline phosphatase activity, alpha-glucosidase activity, and beta-glucuronidase activity.
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Three cases of opportunistic infection caused by propionic acid producingCorynebacterium minutissimum
European Journal of Clinical Microbiology and Infectious Diseases, 1992Co-Authors: B. Bosterhaut, R. Cuvelier, E. Serruys, F. Pouthier, G. WautersAbstract:Propionic acid producing strains of Corynebacterium minutissimum were isolated from three patients with opportunistic infections. One neutropenic patient was undergoing chemotherapy for prolymphocytic leukemia; the other two patients were undergoing hemodialysis and peritoneal dialysis respectively. An unusual feature of these three strains was their resistance to several antibiotics, which is seldom seen in diphtheroids other than Corynebacterium jeikeium and CDC group D2.
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Three cases of opportunistic infection caused by propionic acid producing Corynebacterium minutissimum.
European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology, 1992Co-Authors: B. Van Bosterhaut, R. Cuvelier, E. Serruys, F. Pouthier, G. WautersAbstract:Propionic acid producing strains of Corynebacterium minutissimum were isolated from three patients with opportunistic infections. One neutropenic patient was undergoing chemotherapy for prolymphocytic leukemia; the other two patients were undergoing hemodialysis and peritoneal dialysis respectively. An unusual feature of these three strains was their resistance to several antibiotics, which is seldom seen in diphtheroids other than Corynebacterium jeikeium and CDC group D2.
Gloria García-calvo - One of the best experts on this subject based on the ideXlab platform.
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In Vitro Susceptibilities of Aerobic and Facultative Non-Spore-Forming Gram-Positive Bacilli to HMR 3647 (RU 66647) and 14 Other Antimicrobials
Antimicrobial agents and chemotherapy, 1998Co-Authors: Francisco Soriano, Ricardo Fernández-roblas, R. Calvo, Gloria García-calvoAbstract:The comparative in vitro activity of the ketolide HMR 3647 (RU 66647) and those of structurally related macrolide-lincosamide-streptogramin compounds (erythromycin, roxithromycin, azithromycin, clarithromycin, josamycin, lincomycin, pristinamycin, and quinupristin-dalfopristin) as well as those of benzylpenicillin, doxycycline, vancomycin, teicoplanin, levofloxacin, and rifapentine against 247 aerobic and facultative non-spore-forming gram-positive bacilli were determined by an agar dilution method. The ketolide was active against most organisms tested except Corynebacterium striatum, coryneform CDC group 12, and Oerskovia spp. The frequency of resistance to erythromycin and other macrolides as well as that to lincomycin was high. Pristinamycin and, to a lesser extent, quinupristin-dalfopristin were very active, but resistance to these agents was present in some strains of Rhodococcus equi, Listeria spp., C. striatum, Erysipelothrix rhusiopathiae, and Oerskovia spp. HMR 3647 was very active against all erythromycin-sensitive and many erythromycin-nonsusceptible strains, especially Corynebacterium minutissimum, Corynebacterium pseudodiphtheriticum, Corynebacterium amycolatum, and Corynebacterium jeikeium. In vitro resistance to benzylpenicillin was common, but doxycycline, vancomycin, and teicoplanin were very active against most organisms tested except E. rhusiopathiae, against which glycopeptide antibiotics were not active. The in vitro activity of levofloxacin was remarkable, but resistance to this agent was common for C. amycolatum, Corynebacterium urealyticum, C. jeikeium, and Oerskovia spp. strains. Rifapentine was also very active in vitro against many organisms, but resistance to this agent was always present in E. rhusiopathiae and was very common in C. striatum and C. urealyticum.
Philippe Riegel - One of the best experts on this subject based on the ideXlab platform.
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Identification of Nonlipophilic Corynebacteria Isolated from Dairy Cows with Mastitis
Journal of clinical microbiology, 1999Co-Authors: J Hommez, Philippe Riegel, Luc Devriese, Mario Vaneechoutte, Patrick Butaye, Freddy HaesebrouckAbstract:Nonlipophilic corynebacteria associated with clinical and subclinical mastitis in dairy cows were found to belong to four species: Corynebacterium amycolatum, Corynebacterium ulcerans, Corynebacterium pseudotuberculosis, and Corynebacterium minutissimum. These species may easily be confused. However, clear-cut differences between C. ulcerans and C. pseudotuberculosis were found in their acid production from maltotriose and ethylene glycol, susceptibility to vibriostatic agent O129, and alkaline phosphatase. Absence of growth at 20°C and lack of α-glucosidase and 4MU-α-d-glycoside hydrolysis activity differentiated C. amycolatum from C. pseudotuberculosis and C. ulcerans. The mastitis C. pseudotuberculosis strains differed from the biovar equi and ovis reference strains and from caprine field strains in their colony morphologies and in their reduced inhibitory activity on staphylococcal β-hemolysin. C. amycolatum was the most frequently isolated nonlipophilic Corynebacterium.
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Corynebacterium singulare sp. nov., a New Species for Urease-Positive Strains Related to Corynebacterium minutissimum
International journal of systematic bacteriology, 1997Co-Authors: Philippe Riegel, Raymond Ruimy, François Renaud, Jean Freney, Gilles Prévost, François Jehl, Richard Christen, Henri MonteilAbstract:We studied two coryneform strains from clinical specimens. These strains had type IV and corynemycolic acids in their cell walls and also had phenotypic characteristics, such as urease activity and fermentation of glucose and sucrose but not trehalose, which did not permit assignment to any previously recognized taxon. According to DNA-DNA hybridization data, these two strains are members of the same species (level of DNA similarity, 86%). Phylogenetic analysis based on comparisons of almost complete small-subunit ribosomal DNA sequences revealed that these strains are closely related to Corynebacterium minutissimum, but DNA relatedness experiments clearly showed that they constitute a distinct new species with a level of DNA relatedness to the C. minutissimum type strain of less than 40%. This new species can be differentiated from C. minutissimum strains by its enzymatic activities and carbon source utilization, and the name Corynebacterium singulare is proposed for it. The type strain is strain IBS B52218 (= CCUG 37330), which was isolated from a semen specimen.
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Urease-Positive Strains Related to
1997Co-Authors: Philippe Riegel, Raymond Ruimy, François Renaud, Jean Freney, Gilles Prévost, François Jehl, Richard ChristenAbstract:We studied two coryneform strains from clinical specimens. These strains had type IV and corynemycolic acids in their cell walls and also had phenotypic characteristics, such as urease activity and fermentation of glucose and sucrose but not trehalose, which did not permit assignment to any previously recognized taxon. According to DNA-DNA hybridization data, these two strains are members of the same species (level of DNA similarity, 86%). Phylogenetic analysis based on comparisons of almost complete small-subunit ribosomal DNA sequences revealed that these strains are closely related to Corynebacterium minutissimum, but DNA relatedness experiments clearly showed that they constitute a distinct new species with a level of DNA relatedness to the C. minutissimum type strain of less than 40%. This new species can be differentiated from C. minutissimum strains by its enzymatic activities and carbon source utilization, and the name Corynebacterium singulare is proposed for it. The type strain is strain IBS B52218 (= CCUG 37330), which was isolated from a semen specimen. During an attempt to identify coryneform rods encountered in clinical sources, we isolated two strains which exhibited similar phenotypic characteristics but differed from previously recognized coryneform taxa. The presence of type IV and corynemycolic acids in the cell walls of the organisms supported their assignment to the genus Coiynebacterium, and these two strains were found to possess a urease but not a nitrate reductase and to produce acid from glucose, sucrose, and maltose. In fact, except for the presence of a urease, these two strains resembled Corynebacterium minutissimum based on the morphology of colonies or commonly used biochemical tests (4). In order to determine the taxonomic position of these two unidentified isolates, we studied them and strains of Corynebacterium species by performing a biochemical analysis, a DNA-DNA hybridization analysis, and a small-subunit ribosomal DNA (rDNA) sequences analysis. On the basis of our results and previous phylogenetic studies of the genus Coiynebacterium (11, IS), we propose a new species, Corynebacterium singulare, for these two urease-positive strains related to C. minutissimum. MATERIALS AND METHODS Strains, media, and growth conditions. The two strains of unidentified coryneform rods were isolated at the Institute of Bacteriology of Strasbourg from a semen specimen (strain IBS B5221ST) and a blood specimen (strain IBS T22913) from two patients. Type strain NCTC 10288 (= ATCC 23348) of C. minutissimum was obtained from the National Collection of Type Cultures. In addition, 18 C. minutissimum wild strains were obtained from the Institute of Bacteriology of Strasbourg or from the personal collection of F. Renaud, University Institute of Technology, Villeurbanne, France. These strains were identified as C. minutissirnurn strains by using recently published schemes (13, 22,23). Bacteria were grown aerobically at 37°C on Trypticase soy agar (bioMCrieux, Marcy-l'Etoile, France) and on Trypticase soy agar supplemented with 5% (vol/vol) sheep blood. Biochemical tests. For the most part, the MI Coryne system and a biotype 100 gallery were used with all strains according to the instructions of the manufac
