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Ellie J. C. Goldstein - One of the best experts on this subject based on the ideXlab platform.
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in vitro activities of the new semisynthetic glycopeptide telavancin td 6424 vancomycin daptomycin linezolid and four comparator agents against anaerobic gram positive species and corynebacterium spp
Antimicrobial Agents and Chemotherapy, 2004Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, Vreni C Merriam, Helen T FernandezAbstract:Telavancin is a new semisynthetic glycopeptide anti-infective with multiple mechanisms of action, including inhibition of bacterial membrane phospholipid synthesis and inhibition of bacterial cell wall synthesis. We determined the in vitro activities of telavancin, vancomycin, daptomycin, linezolid, quinupristin-dalfopristin, imipenem, piperacillin-tazobactam, and ampicillin against 268 clinical isolates of anaerobic gram-positive organisms and 31 Corynebacterium strains using agar dilution methods according to National Committee for Clinical Laboratory Standards procedures. Plates with daptomycin were supplemented with Ca2+ to 50 mg/liter. The MICs at which 90% of isolates tested were inhibited (MIC90s) for telavancin and vancomycin were as follows: Actinomyces spp. (n = 45), 0.25 and 1 μg/ml, respectively; Clostridium difficile (n = 14), 0.25 and 1 μg/ml, respectively; Clostridium ramosum (n = 16), 1 and 4 μg/ml, respectively; Clostridium innocuum (n = 15), 4 and 16 μg/ml, respectively; Clostridium clostridioforme (n = 15), 8 and 1 μg/ml, respectively; Eubacterium group (n = 33), 0.25 and 2 μg/ml, respectively; Lactobacillus spp. (n = 26), 0.5 and 4 μg/ml, respectively; Propionibacterium spp. (n = 34), 0.125 and 0.5 μg/ml, respectively; Peptostreptococcus spp. (n = 52), 0.125 and 0.5 μg/ml, respectively; and Corynebacterium spp. (n = 31), 0.03 and 0.5 μg/ml, respectively. The activity of TD-6424 was similar to that of quinupristin-dalfopristin for most strains except C. clostridioforme and Lactobacillus casei, where quinupristin-dalfopristin was three- to fivefold more active. Daptomycin had decreased activity (MIC > 4 μg/ml) against 14 strains of Actinomyces spp. and all C. ramosum, Eubacterium lentum, and Lactobacillus plantarum strains. Linezolid showed decreased activity (MIC > 4 μg/ml) against C. ramosum, two strains of C. difficile, and 15 strains of Lactobacillus spp. Imipenem and piperacillin-tazobactam were active against >98% of strains. The MICs of ampicillin for eight Clostridium spp. and three strains of L. casei were >1 μg/ml. The MIC90 of TD-6424 for all strains tested was ≤2 μg/ml. TD-6424 has potential for use against infections with gram-positive anaerobes and deserves further clinical evaluation.
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in vitro activities of daptomycin vancomycin quinupristin dalfopristin linezolid and five other antimicrobials against 307 gram positive anaerobic and 31 corynebacterium clinical isolates
Antimicrobial Agents and Chemotherapy, 2003Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi A. Warren, Vreni C Merriam, Kerrin L Tyrrell, Helen T FernandezAbstract:The activities of daptomycin, a cyclic lipopeptide, and eight other agents were determined against 338 strains of gram-positive anaerobic bacteria and corynebacteria by the NCCLS reference agar dilution method with supplemented brucella agar for the anaerobes and Mueller-Hinton agar for the corynebacteria. The daptomycin MICs determined on Ca(2+)-supplemented (50 mg/liter) brucella agar plates were one- to fourfold lower than those determined in unsupplemented media. Daptomycin was highly active (MICs, 8 microg/ml were inhibited by or=4 microg/ml for most strains of Clostridium clostridioforme, Clostridium paraputrificum, Clostridium tertium, and Clostridium ramosum; the isolates were generally more resistant to other antimicrobials. Daptomycin was two- to fourfold less active against Actinomyces spp. than vancomycin, quinupristin-dalfopristin, or linezolid. Twenty-nine of 31 strains of Corynebacterium spp., including Corynebacterium jeikeium, Corynebacterium amycolatum, and Corynebacterium pseudodiphtheriticum, were inhibited by
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In Vitro Activity of Gemifloxacin (SB 265805) against Anaerobes
Antimicrobial agents and chemotherapy, 1999Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, C. Vreni MerriamAbstract:Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 105 CFU/spot. Comparative antimicrobials tested included trovafloxacin, levofloxacin, grepafloxacin, sparfloxacin, sitafloxacin (DU-6859a), penicillin G, amoxicillin clavulanate, imipenem, cefoxitin, clindamycin, and metronidazole. The MIC50 and MIC90 (MICs at which 50 and 90% of the isolates were inhibited) of gemifloxacin against various organisms (with the number of strains tested in parentheses) were as follows (in micrograms per milliliter): for Bacteroides fragilis (28), 0.5 and 2; for Bacteroides thetaiotaomicron (24), 1 and 16; for Bacteroides caccae (12), 1 and 16; for Bacteroides distasonis (12), 8 and >16; for Bacteroides ovatus (12), 4 and >16; for Bacteroides stercoris (12), 0.5 and 0.5; for Bacteroides uniformis (12), 1 and 4; for Bacteroides vulgatus (11), 4 and 4; for Clostridium clostridioforme (15), 0.5 and 0.5; for Clostridium difficile (15), 1 and >16; for Clostridium innocuum (13), 0.125 and 2; for Clostridium perfringens (13), 0.06 and 0.06; for Clostridium ramosum (14), 0.25 and 8; for Fusobacterium nucleatum (12), 0.125 and 0.25; for Fusobacterium necrophorum (11), 0.25 and 0.5; for Fusobacterium varium (13), 0.5 and 1; for Fusobacterium spp. (12), 1 and 2; for Peptostreptococcus anaerobius (13), 0.06 and 0.06; for Peptostreptococcus asaccharolyticus (13), 0.125 and 0.125; for Peptostreptococcus magnus (14), 0.03 and 0.03; for Peptostreptococcus micros (12), 0.06 and 0.06; for Peptostreptococcus prevotii (14), 0.06 and 0.25; for Porphyromonas asaccharolytica (11), 0.125 and 0.125; for Prevotella bivia (10), 8 and 16; for Prevotella buccae (10), 2 and 2; for Prevotella intermedia (10), 0.5 and 0.5; and for Prevotella melaninogenica (11), 1 and 1. Gemifloxacin mesylate (SB 265805) was 1 to 4 dilutions more active than trovafloxacin against fusobacteria and peptostreptococci, and the two drugs were equivalent against clostridia and P. asaccharolytica. Gemifloxacin was equivalent to sitafloxacin (DU 6859a) against peptostreptococci, C. perfringens, and C. ramosum, and sitafloxacin was 2 to 3 dilutions more active against fusobacteria. Sparfloxacin, grepafloxacin, and levofloxacin were generally less active than gemifloxacin against all anaerobes.
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In Vitro Activity of Gemifloxacin (SB 265805) against Anaerobes
1999Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi Warren, Kerin Tyrrell, Vreni C MerriamAbstract:Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 105 CFU/spot. Comparative antimicrobials tested included trovafloxacin, levofloxacin, grepafloxacin, sparfloxacin, sitafloxacin (DU-6859a), penicillin G, amoxicillin clavulanate, imipenem, cefoxitin, clindamycin, and metronidazole. The MIC50 and MIC90 (MICs at which 50 and 90 % of the isolates were inhibited) of gemifloxacin against various organisms (with the number of strains tested in parentheses) were as follows (in micrograms per milliliter): for Bacteroides fragilis (28), 0.5 and 2; for Bacteroides thetaiotaomicron (24), 1 and 16; for Bacteroides caccae (12), 1 and 16; for Bacteroides distasonis (12), 8 and>16; for Bacteroides ovatus (12), 4 and>16; for Bacteroides stercoris (12), 0.5 and 0.5; for Bacteroides uniformis (12), 1 and 4; for Bacteroides vulgatus (11), 4 and 4; for Clostridium clostridioforme (15), 0.5 and 0.5; for Clostridium difficile (15), 1 and>16; for Clostridium innocuum (13), 0.125 and 2; for Clostridium perfringens (13), 0.06 and 0.06; for Clostridium ramosum (14), 0.25 and 8; for Fusobacterium nucleatum (12), 0.125 and 0.25; for Fusobacterium necrophorum (11), 0.25 and 0.5; for Fusobacterium varium (13), 0.5 and 1; for Fusobacterium spp. (12), 1 and 2; for Peptostreptococcus anaerobius (13), 0.06 and 0.06; for Peptostreptococcus asaccharolyticus (13), 0.125 and 0.125; for Peptostreptococcus magnus (14), 0.03 and 0.03; for Peptostreptococcu
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identification and antimicrobial resistance patterns of clinical isolates of Clostridium clostridioforme Clostridium innocuum and Clostridium ramosum compared with those of clinical isolates of Clostridium perfringens
Journal of Clinical Microbiology, 1995Co-Authors: Carolyn J. Alexander, J S Brazier, Diane M. Citron, Ellie J. C. GoldsteinAbstract:Clostridium ramosum, C. innocuum, and C. clostridioforme are frequently isolated from clinical specimens including blood. Because of Gram stain variability, a lack of spores, and atypical colonial morphology, identification of these species is often difficult. Three anaerobe identification kits were evaluated for their abilities to identify these species. For comparison, 11 strains of C. perfringens were evaluated in parallel. By using profile numbers and codebooks, the correct genus and species were identified, as follows: with the RapID ANA II kit, 100% (20 of 20) of C. ramosum isolates, 24% (5 of 21) of C. innocuum isolates, and 50% (10 of 20) of C. clostridioforme isolates; with the AnIDent kit, 60% (12 of 20) of C. ramosum isolates, 28% (6 of 21) of C. innocuum isolates, and 90% (18 of 20) of C. clostridioforme isolates; with the ATB32A kit, 70% (14 of 20) of C. ramosum isolates, 0% (0 of 21) of C. innocuum isolates, and 40% (8 of 20) of C. clostridioforme isolates. Profile numbers that overlapped several species were obtained as follows: with the RapID ANA II kit, 0% of C. ramosum isolates, 76% of C. innocuum isolates, and 40% of C. clostridioforme isolates; with the AnIDent kit 40% of C. ramosum isolates, 62% of C. innocuum isolates, and 5% of C. clostridioforme isolates; with the ATB32A kit, 15% of C. ramosum isolates, 52% of C. innocuum isolates, and 25% of C. clostridioforme isolates. One strain of C. innocuum was misidentified by the AnIDent kit, and the remainder yielded profile numbers that were not listed in the codebooks. The MICs of 11 antimicrobial agents including penicillin G, metronidazole, clindamycin, cefoxitin, cefotetan, imipenem, meropenem, amoxicillin-clavulanate, ampicillin-sulbactam, piperacillin-tazobactam, and vancomycin were determined by the agar dilution method. All C. perfringens strains were susceptible to all antimicrobial agents tested. Various levels of resistance to cefoxitin, cefotetan, and penicillin G were noted with C. ramosum, C. clostridioforme, and C. innocuum. In addition, resistance to clindamycin was noted with C. ramosum (5%) and C. innocuum (10%). Most strains of C. innocuum were only moderately susceptible to vancomycin (MIC at which 90% of strains are inhibited, 4 micrograms/ml).
Diane M. Citron - One of the best experts on this subject based on the ideXlab platform.
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Comparative in vitro activities of LFF571 against Clostridium difficile and 630 other intestinal strains of aerobic and anaerobic bacteria
2012Co-Authors: Diane M. Citron, Kerin A L. Tyrrell, A Vreni C. Merriam, Ellie J. C. GoldsteinaAbstract:The in vitro activities of LFF571, a novel analog of GE2270A that inhibits bacterial growth by binding with high affinity for pro-tein synthesis elongation factor Tu, fidaxomicin, and 10 other antimicrobial agents were determined against 50 strains of Clos-tridium difficile and 630 other anaerobic and aerobic organisms of intestinal origin. LFF571 possesses potent activity against C. difficile andmost other Gram-positive anaerobes (MIC90,<0.25g/ml), with the exception of bifidobacteria and lactobacilli. The MIC90s for aerobes, including enterococci, Staphylococcus aureus (as well as methicillin-resistant S. aureus [MRSA] iso-lates), Streptococcus pyogenes, and other streptococci were 0.06, 0.125, 2, and 8g/ml, respectively. Comparatively, fidaxomicin showed variable activity against Gram-positive organisms: MIC90s against C. difficile, Clostridium perfringens, and Bifidobacte-rium spp. were 0.5,<0.015, and 0.125g/ml, respectively, but>32g/ml against Clostridium ramosum and Clostridium in-nocuum.MIC90 for S. pyogenes and other streptococci was 16 and>32g/ml, respectively. LFF571 and fidaxomicin were gener-ally less active against Gram-negative anaerobes. Toxigenic strains of Clostridium difficile are responsible for aspectrum of antibiotic-associated diarrheal diseases (C. diffi-cile infection [CDI]) through elaboration of toxins A and B and other virulence factors (3, 9). In recent years, a hypervirulent strain (NAP-1, 027, BI) has emerged causing more severe disease and higher mortality, especially in more susceptible elderly pa
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in vitro activities of the new semisynthetic glycopeptide telavancin td 6424 vancomycin daptomycin linezolid and four comparator agents against anaerobic gram positive species and corynebacterium spp
Antimicrobial Agents and Chemotherapy, 2004Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, Vreni C Merriam, Helen T FernandezAbstract:Telavancin is a new semisynthetic glycopeptide anti-infective with multiple mechanisms of action, including inhibition of bacterial membrane phospholipid synthesis and inhibition of bacterial cell wall synthesis. We determined the in vitro activities of telavancin, vancomycin, daptomycin, linezolid, quinupristin-dalfopristin, imipenem, piperacillin-tazobactam, and ampicillin against 268 clinical isolates of anaerobic gram-positive organisms and 31 Corynebacterium strains using agar dilution methods according to National Committee for Clinical Laboratory Standards procedures. Plates with daptomycin were supplemented with Ca2+ to 50 mg/liter. The MICs at which 90% of isolates tested were inhibited (MIC90s) for telavancin and vancomycin were as follows: Actinomyces spp. (n = 45), 0.25 and 1 μg/ml, respectively; Clostridium difficile (n = 14), 0.25 and 1 μg/ml, respectively; Clostridium ramosum (n = 16), 1 and 4 μg/ml, respectively; Clostridium innocuum (n = 15), 4 and 16 μg/ml, respectively; Clostridium clostridioforme (n = 15), 8 and 1 μg/ml, respectively; Eubacterium group (n = 33), 0.25 and 2 μg/ml, respectively; Lactobacillus spp. (n = 26), 0.5 and 4 μg/ml, respectively; Propionibacterium spp. (n = 34), 0.125 and 0.5 μg/ml, respectively; Peptostreptococcus spp. (n = 52), 0.125 and 0.5 μg/ml, respectively; and Corynebacterium spp. (n = 31), 0.03 and 0.5 μg/ml, respectively. The activity of TD-6424 was similar to that of quinupristin-dalfopristin for most strains except C. clostridioforme and Lactobacillus casei, where quinupristin-dalfopristin was three- to fivefold more active. Daptomycin had decreased activity (MIC > 4 μg/ml) against 14 strains of Actinomyces spp. and all C. ramosum, Eubacterium lentum, and Lactobacillus plantarum strains. Linezolid showed decreased activity (MIC > 4 μg/ml) against C. ramosum, two strains of C. difficile, and 15 strains of Lactobacillus spp. Imipenem and piperacillin-tazobactam were active against >98% of strains. The MICs of ampicillin for eight Clostridium spp. and three strains of L. casei were >1 μg/ml. The MIC90 of TD-6424 for all strains tested was ≤2 μg/ml. TD-6424 has potential for use against infections with gram-positive anaerobes and deserves further clinical evaluation.
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in vitro activities of daptomycin vancomycin quinupristin dalfopristin linezolid and five other antimicrobials against 307 gram positive anaerobic and 31 corynebacterium clinical isolates
Antimicrobial Agents and Chemotherapy, 2003Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi A. Warren, Vreni C Merriam, Kerrin L Tyrrell, Helen T FernandezAbstract:The activities of daptomycin, a cyclic lipopeptide, and eight other agents were determined against 338 strains of gram-positive anaerobic bacteria and corynebacteria by the NCCLS reference agar dilution method with supplemented brucella agar for the anaerobes and Mueller-Hinton agar for the corynebacteria. The daptomycin MICs determined on Ca(2+)-supplemented (50 mg/liter) brucella agar plates were one- to fourfold lower than those determined in unsupplemented media. Daptomycin was highly active (MICs, 8 microg/ml were inhibited by or=4 microg/ml for most strains of Clostridium clostridioforme, Clostridium paraputrificum, Clostridium tertium, and Clostridium ramosum; the isolates were generally more resistant to other antimicrobials. Daptomycin was two- to fourfold less active against Actinomyces spp. than vancomycin, quinupristin-dalfopristin, or linezolid. Twenty-nine of 31 strains of Corynebacterium spp., including Corynebacterium jeikeium, Corynebacterium amycolatum, and Corynebacterium pseudodiphtheriticum, were inhibited by
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In Vitro Activity of Gemifloxacin (SB 265805) against Anaerobes
Antimicrobial agents and chemotherapy, 1999Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, C. Vreni MerriamAbstract:Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 105 CFU/spot. Comparative antimicrobials tested included trovafloxacin, levofloxacin, grepafloxacin, sparfloxacin, sitafloxacin (DU-6859a), penicillin G, amoxicillin clavulanate, imipenem, cefoxitin, clindamycin, and metronidazole. The MIC50 and MIC90 (MICs at which 50 and 90% of the isolates were inhibited) of gemifloxacin against various organisms (with the number of strains tested in parentheses) were as follows (in micrograms per milliliter): for Bacteroides fragilis (28), 0.5 and 2; for Bacteroides thetaiotaomicron (24), 1 and 16; for Bacteroides caccae (12), 1 and 16; for Bacteroides distasonis (12), 8 and >16; for Bacteroides ovatus (12), 4 and >16; for Bacteroides stercoris (12), 0.5 and 0.5; for Bacteroides uniformis (12), 1 and 4; for Bacteroides vulgatus (11), 4 and 4; for Clostridium clostridioforme (15), 0.5 and 0.5; for Clostridium difficile (15), 1 and >16; for Clostridium innocuum (13), 0.125 and 2; for Clostridium perfringens (13), 0.06 and 0.06; for Clostridium ramosum (14), 0.25 and 8; for Fusobacterium nucleatum (12), 0.125 and 0.25; for Fusobacterium necrophorum (11), 0.25 and 0.5; for Fusobacterium varium (13), 0.5 and 1; for Fusobacterium spp. (12), 1 and 2; for Peptostreptococcus anaerobius (13), 0.06 and 0.06; for Peptostreptococcus asaccharolyticus (13), 0.125 and 0.125; for Peptostreptococcus magnus (14), 0.03 and 0.03; for Peptostreptococcus micros (12), 0.06 and 0.06; for Peptostreptococcus prevotii (14), 0.06 and 0.25; for Porphyromonas asaccharolytica (11), 0.125 and 0.125; for Prevotella bivia (10), 8 and 16; for Prevotella buccae (10), 2 and 2; for Prevotella intermedia (10), 0.5 and 0.5; and for Prevotella melaninogenica (11), 1 and 1. Gemifloxacin mesylate (SB 265805) was 1 to 4 dilutions more active than trovafloxacin against fusobacteria and peptostreptococci, and the two drugs were equivalent against clostridia and P. asaccharolytica. Gemifloxacin was equivalent to sitafloxacin (DU 6859a) against peptostreptococci, C. perfringens, and C. ramosum, and sitafloxacin was 2 to 3 dilutions more active against fusobacteria. Sparfloxacin, grepafloxacin, and levofloxacin were generally less active than gemifloxacin against all anaerobes.
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In Vitro Activity of Gemifloxacin (SB 265805) against Anaerobes
1999Co-Authors: Ellie J. C. Goldstein, Diane M. Citron, Yumi Warren, Kerin Tyrrell, Vreni C MerriamAbstract:Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 105 CFU/spot. Comparative antimicrobials tested included trovafloxacin, levofloxacin, grepafloxacin, sparfloxacin, sitafloxacin (DU-6859a), penicillin G, amoxicillin clavulanate, imipenem, cefoxitin, clindamycin, and metronidazole. The MIC50 and MIC90 (MICs at which 50 and 90 % of the isolates were inhibited) of gemifloxacin against various organisms (with the number of strains tested in parentheses) were as follows (in micrograms per milliliter): for Bacteroides fragilis (28), 0.5 and 2; for Bacteroides thetaiotaomicron (24), 1 and 16; for Bacteroides caccae (12), 1 and 16; for Bacteroides distasonis (12), 8 and>16; for Bacteroides ovatus (12), 4 and>16; for Bacteroides stercoris (12), 0.5 and 0.5; for Bacteroides uniformis (12), 1 and 4; for Bacteroides vulgatus (11), 4 and 4; for Clostridium clostridioforme (15), 0.5 and 0.5; for Clostridium difficile (15), 1 and>16; for Clostridium innocuum (13), 0.125 and 2; for Clostridium perfringens (13), 0.06 and 0.06; for Clostridium ramosum (14), 0.25 and 8; for Fusobacterium nucleatum (12), 0.125 and 0.25; for Fusobacterium necrophorum (11), 0.25 and 0.5; for Fusobacterium varium (13), 0.5 and 1; for Fusobacterium spp. (12), 1 and 2; for Peptostreptococcus anaerobius (13), 0.06 and 0.06; for Peptostreptococcus asaccharolyticus (13), 0.125 and 0.125; for Peptostreptococcus magnus (14), 0.03 and 0.03; for Peptostreptococcu
Kimitaka Tani - One of the best experts on this subject based on the ideXlab platform.
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fatal fournier s gangrene caused by Clostridium ramosum in a patient with central diabetes insipidus and insulin dependent diabetes mellitus a case report
BMC Infectious Diseases, 2018Co-Authors: Noriyoshi Takano, Junichi Yatabe, Masaaki Kato, Daisuke Sueoka, Shigekazu Iguchi, Atsushi Yoshida, Yutaka Uzawa, Ken Kikuchi, Midori Yatabe, Kimitaka TaniAbstract:Clostridium ramosum is a generally non-pathogenic enteric anaerobe, and Fournier’s gangrene is a rare necrotizing soft tissue infection with male predisposition affecting the perineum and the genital area. We report, to our knowledge, the first case of Fournier’s gangrene caused by C. ramosum in a female patient with multiple underlying conditions. A 44-year-old woman with a 6-year history of insulin-dependent diabetes mellitus after total pancreatectomy and an 11-year history of central diabetes insipidus developed a pain in the genital area after a month of urinary catheter use. The lower abdominal pain worsened gradually over 2 weeks, and the pain, general fatigue, and loss of appetite prompted the patient’s hospital admission. As she had severe edema in her pelvic and bilateral femoral areas, ceftriaxone was started empirically after collecting two sets of blood cultures. On hospital day 2, CT examination revealed the presence of necrotizing faciitis in the genital and pelvic areas, and the antibiotics were changed to a combination of meropenem, vancomycin, and clindamycin. Gram-positive cocci and gram-positive rods were isolated from blood cultures, which were finally identified as Streptococcus constellatus and C. ramosum using superoxide dismutase and 16S rDNA sequencing. An emergent surgery was performed on hospital day 2 to remove the affected tissue. Despite undergoing debridement and receiving combined antimicrobial chemotherapies, the patient’s clinical improvement remained limited. The patient’s condition continued to deteriorate, and she eventually died on hospital day 8. In the present case, the underlying diabetes mellitus, urinary incontinence due to central diabetes insipidus, undernutrition, and edema served as the predisposing conditions. C. ramosum is a potentially opportunistic pathogen among immunosuppressed persons and a rare cause of necrotizing fasciitis.
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Fatal Fournier’s gangrene caused by Clostridium ramosum in a patient with central diabetes insipidus and insulin-dependent diabetes mellitus: a case report
BMC, 2018Co-Authors: Noriyoshi Takano, Midori Sasaki Yatabe, Junichi Yatabe, Masaaki Kato, Daisuke Sueoka, Shigekazu Iguchi, Atsushi Yoshida, Yutaka Uzawa, Ken Kikuchi, Kimitaka TaniAbstract:Abstract Background Clostridium ramosum is a generally non-pathogenic enteric anaerobe, and Fournier’s gangrene is a rare necrotizing soft tissue infection with male predisposition affecting the perineum and the genital area. We report, to our knowledge, the first case of Fournier’s gangrene caused by C. ramosum in a female patient with multiple underlying conditions. Case presentation A 44-year-old woman with a 6-year history of insulin-dependent diabetes mellitus after total pancreatectomy and an 11-year history of central diabetes insipidus developed a pain in the genital area after a month of urinary catheter use. The lower abdominal pain worsened gradually over 2 weeks, and the pain, general fatigue, and loss of appetite prompted the patient’s hospital admission. As she had severe edema in her pelvic and bilateral femoral areas, ceftriaxone was started empirically after collecting two sets of blood cultures. On hospital day 2, CT examination revealed the presence of necrotizing faciitis in the genital and pelvic areas, and the antibiotics were changed to a combination of meropenem, vancomycin, and clindamycin. Gram-positive cocci and gram-positive rods were isolated from blood cultures, which were finally identified as Streptococcus constellatus and C. ramosum using superoxide dismutase and 16S rDNA sequencing. An emergent surgery was performed on hospital day 2 to remove the affected tissue. Despite undergoing debridement and receiving combined antimicrobial chemotherapies, the patient’s clinical improvement remained limited. The patient’s condition continued to deteriorate, and she eventually died on hospital day 8. In the present case, the underlying diabetes mellitus, urinary incontinence due to central diabetes insipidus, undernutrition, and edema served as the predisposing conditions. Conclusions C. ramosum is a potentially opportunistic pathogen among immunosuppressed persons and a rare cause of necrotizing fasciitis
Knud Poulsen - One of the best experts on this subject based on the ideXlab platform.
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SDS-PAGE of IgA1 (Ale) myeloma protein.
2014Co-Authors: Kazuo Takahashi, Knud Poulsen, Mogens Kilian, Milan Raska, Milada Stuchlova Horynova, Stacy D. Hall, Yoshiyuki Hiki, Yukio Yuzawa, Zina Moldoveanu, Bruce A. JulianAbstract:IgA1 proteins were separated by SDS-PAGE under reducing conditions and the protein bands were silver stained. IgA1 was untreated or sialylated with ST3Gal1 (ST3) or ST6GalNAcI (ST6) sialyltransferases and the Fc and Fd fragments of the heavy chains were generated using IgA-specific protease from Clostridium ramosum AK183 (see Fig. 1). Mobility change of Fc fragments after sialyltransferase reactions confirmed sialylation of HR O-glycans.
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Structure of IgA1 and the hinge-region (HR) amino-acid sequence.
2014Co-Authors: Kazuo Takahashi, Knud Poulsen, Mogens Kilian, Milan Raska, Milada Stuchlova Horynova, Stacy D. Hall, Yoshiyuki Hiki, Yukio Yuzawa, Zina Moldoveanu, Bruce A. JulianAbstract:(A) Monomeric IgA1 and its HR with nine possible sites of O-glycan attachment and the Fc portion of heavy chain with two N-glycans. Underlined serine (S) and threonine (T) residues in HR are frequently glycosylated [26], [30], [31]. Arrows show cleavage sites of trypsin and two IgA-specific proteases (from Clostridium ramosum AK183 and Haemophilus influenzae HK50). (B) O-glycan variants of circulatory IgA1∶1, Tn antigen; 2, sialyl-Tn antigen; 3, T antigen; 4, α3-sialyl-T antigen; 5, α6-sialyl-T antigen; 6, disialyl-T antigen. Abbreviations: GalNAc, N-acetylgalactosamine; Gal, galactose; NeuAc, N-acetylneuraminic acid.
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the iga protease of Clostridium ramosum
Handbook of Proteolytic Enzymes (Second Edition)#R##N#Aspartic and Metallo Peptidases, 2013Co-Authors: Jan Potempa, Knud PoulsenAbstract:Publisher Summary This chapter elaborates the structural chemistry and the biological aspects of IgA protease of Clostridium ramosum. Bacterial IgA1 proteases are a group of endopeptidases with a remarkable specificity to cleave human IgAl molecules in the hinge region at a single Pro–Ser or Pro–Thr peptide bond. This unique microbial activity that separates the IgA1 molecule into intact Fab and Fc fragments was first identified in fluids of the human digestive tract, and subsequently isolated from Streptococcus sanguis. The enzyme was named IgA protease. C. ramosum IgA protease is highly specific. The enzyme is unable to cleave other human immunoglobulins. The amino acid sequence of the C. ramosum IgA protease deduced from the IgA gene revealed a translation product of 1234 amino acids. The first 30 residues constitute the signal peptide. In the C-terminus, a putative cell wall anchor was identified. The sequence SPQTG presumably constitutes the sortase recognition site. Other features including a small spacer, DNSN, separating the SPQTG motif from a transmembrane domain, IFLWFALLFSAAGVTGITAY, followed by a positively charged tail, NKKKKEHAE, at C-terminus. This strongly argues that the C. ramosum IgA protease is subject to sortase activity.
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iga protease of Clostridium ramosum
2004Co-Authors: Jan Potempa, Knud PoulsenAbstract:Publisher Summary This chapter elaborates the structural chemistry and the biological aspects of IgA protease of Clostridium ramosum. Bacterial IgA1 proteases are a group of endopeptidases with a remarkable specificity to cleave human IgAl molecules in the hinge region at a single Pro–Ser or Pro–Thr peptide bond. This unique microbial activity that separates the IgA1 molecule into intact Fab and Fc fragments was first identified in fluids of the human digestive tract, and subsequently isolated from Streptococcus sanguis. The enzyme was named IgA protease. C. ramosum IgA protease is highly specific. The enzyme is unable to cleave other human immunoglobulins. The amino acid sequence of the C. ramosum IgA protease deduced from the IgA gene revealed a translation product of 1234 amino acids. The first 30 residues constitute the signal peptide. In the C-terminus, a putative cell wall anchor was identified. The sequence SPQTG presumably constitutes the sortase recognition site. Other features including a small spacer, DNSN, separating the SPQTG motif from a transmembrane domain, IFLWFALLFSAAGVTGITAY, followed by a positively charged tail, NKKKKEHAE, at C-terminus. This strongly argues that the C. ramosum IgA protease is subject to sortase activity.
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the Clostridium ramosum iga proteinase represents a novel type of metalloendopeptidase
Journal of Biological Chemistry, 2002Co-Authors: Klaudia Kosowska, Jan Potempa, Jesper Reinholdt, Lone K Rasmussen, Artur Sabat, Mogens Kilian, Knud PoulsenAbstract:Abstract Clostridium ramosum is part of the normal flora in the human intestine. Some strains produce an IgA proteinase that specifically cleaves human IgA1 and the IgA2m(1) allotype. This prolylendopeptidase was purified from a broth culture supernatant, and N-terminal sequences of the native protein and tryptic fragments thereof were determined. A fragment of the igagene encoding the IgA proteinase was isolated using degenerate primers in PCR, and the complete gene was obtained by inverse PCR. The identity of the iga gene was confirmed by heterologous expression inEscherichia coli. The deduced amino acid sequence indicated a signal peptide of 30 residues and a secreted proteinase of 133,828 Da. A typical Gram-positive cell wall anchor motif was identified in the C terminus. The presence of a putative zinc-binding motif His-Glu-Phe-Gly-His together with inhibition studies indicate that the proteinase belongs to the zinc-dependent metalloproteinases. However, the sequence of the C. ramosumIgA proteinase shows no overall similarity to other proteins except for significant identity around the zinc-binding motif with family M6 of metalloendopeptidases, and the unique sequence of the IgA proteinase in this area presumably establishes a new subfamily. The GC percentage of the iga gene is significantly higher than that for the entire genome of C. ramosum, suggesting that the gene was acquired recently in evolution.
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effect of carbohydrate composition in barley and oat cultivars on microbial ecophysiology and proliferation of salmonella enterica in an in vitro model of the porcine gastrointestinal tract
Applied and Environmental Microbiology, 2009Co-Authors: Robert Pieper, Ji Ri Me Bindelle, B G Rossnagel, Andrew G Van Kessel, Pascal LetermeAbstract:The influence of the carbohydrate (CHO) composition of cereal cultivars on microbial ecophysiology was studied using an in vitro model of the porcine gastrointestinal tract. Ten hull-less barley cultivars, six barley cultivars with hulls, six oat cultivars, and six oat groats that differed in β-glucan, nonstarch polysaccharide (NSP), and starch contents and starch type were hydrolyzed enzymatically and incubated for 72 h with pig feces. Fermentation kinetics were modeled, and microbial compositions and short-chain fatty acid (SCFA) profiles were analyzed using terminal restriction fragment length polymorphism and gas chromatography. Cluster analysis and canonical ordination revealed different effects on fermentation and microbial ecology depending on the type of CHO and cultivar. First, in cultivars of barley with hulls and oats, the cellulose and insoluble NSP contents (i) increased Ruminococcus flavefaciens-like and Clostridium xylanolyticum-like phylotypes, (ii) increased acetate production, and (iii) decreased fermentation activity. Second, in hull-less barley cultivars the β-glucan, amylose, amylopectin, crude protein, and soluble NSP contents determined the microbial community composition and activity as follows: (i) the amylose contents of the hull-less barley varieties increased the butyrate production and the abundance of Clostridium butyricum-like phylotypes, (ii) the β-glucan content determined the total amounts of SCFA, and (iii) the amylopectin and starch contents affected the abundance of Clostridium ramosum-like phylotypes, members of Clostridium cluster XIVa, and Bacteroides-like bacteria. Finally, the effect of CHO on proliferation of Salmonella enterica in the model was determined. Salmonella cell counts were not affected, but the relative proportion of Salmonella decreased with hull-less barley cultivars and increased with oat cultivars as revealed by quantitative PCR. Our results shed light on the complex interactions of cereal CHO with intestinal bacterial ecophysiology and the possible impact on host health.