Clostridium fallax

(aka Bacillus fallax)

Bacteria
General | Carbohydrate O/F | Substrate utilisation | Enzymes | Metabolites | Antibiotics

Overview

  • Clostridium fallax, (aka Bacillus fallax), is a Gram-positive, spore-forming, strictly anaerobic, motile, rod-shaped bacterium. It has been detected in at least 4 gut microbiome compilation studies or metastudies. The DNA G+C content is 26%. Clostridium fallax is probably a rare gut coloniser. (Hall1922; Rainey2011aBergey)



  • This organism has been recovered from human faeces, clinical sources and animals. The risk classification (www.baua.de) for this organism is 2, i.e., risk of individual infection, but low risk of spread (notes: human and animal pathogen). It is an opportunistic pathogen. Is a known gut commensal.
    • QUIRKS
  • Found in human breast milk (Jeurink2013).
    • GENERAL CHARACTERISTICS (Hall1922); (Rainey2011aBergey);
    Character Response
  • Substrates hydrolysed or digested:
  • aesculin; meat;
  • ±
  • Strain-dependent hydrolysis or digestion:
  • milk;
  • 🧂
  • Salt tolerance:
  • doesn't tolerate 6.5% salt;
  • 💧
  • Bile tolerance:
  • Doesn't tolerate 20% bile
  • pH
  • Acidity tolerance:
  • doesn't tolerate pH 8.5;
  • 🌡
  • Temperature tolerance:
  • grows at 30℃; grows at 45℃; Grows optimally at 37℃.
  • ⥅
  • Substrates assimilated or utilised:
  • fructose; galactose; lactose; maltose; mannose; ribose; starch; pyruvate;
  • Active enzymes:
  • DNase;
    • SPECIAL FEATURES (Rainey2011aBergey);
    Character Response
  • ✓
  • Metabolites produced:
  • acetate; butyrate; butanol; Hâ‚‚S; Hâ‚‚; indole;
  • ✓
  • Haemolysis:
  • present
    • RESPONSE TO ANTIBIOTICS (Rainey2011aBergey); (Goldstein2014);
    Class Active Resistant
  • Penicillins:
  • imipenem; penicillin G; piperacillin-tazobactam;
  • Macrolides:
  • fidaxomicin; quinupristin-dalfopristin;
  • Heterocycles:
  • metronidazole;
  • Vancomycins:
  • vancomycin; dalbavancin;
  • Miscellaneous antibiotics:
  • linezolid;

  • Finegold, S. M., Howard, R. A., & Vera, L. S. (1974). Effect of diet on human intestinal fecal flora: comparison of Japanese and American diets. Am. J. Clin. Nutr, 27, 1456–1469.

    • Details

    GENERAL
    Lineage Physiology General Growth Tolerances Hydrol./digest./degr.
    Phylum:  Firmicutes Class:  Clostridia Order:  Eubacteriales Family:  Clostridiaceae Genus:  Clostridium Alt. name:  Bacillus fallax Gram stain:  + O2 Relation.:  strictly anaerobic Spore:  Endospore Motility:  Swimming Morphology:  Rod
    Health:  Unknown
    Source:  human faeces, clinical sources and animals
    DNA G+C(%):  26
    Opt. T:  37℃
    Lower T(℃):  30(+)
    High T(℃):  45(+)
    NaCl >6%:  6.5(neg)
    pH >8:  8.5(neg)
    Bile reaction(%):  20(neg)
    		Aesculin:  + Starch:  neg Milk:  d Meat:  +
    SUBSTRATE ASSIMILATION & UTILISATION
    Monosaccharide util/assim Oligosaccharide util/assim Other carboh. util/assim Amino acid util/assim Organic acid util/assim
    Arabinose:  neg Fructose:  + Galactose:  w(+) Mannose:  w(+) Rhamnose:  neg Ribose:  w(+) Xylose:  neg Cellubiose:  neg Lactose:  w(+) Maltose:  + Melezitose:  neg Raffinose:  neg Sucrose:  neg Trehalose:  neg Amygdalin:  neg Glycogen:  neg Inulin:  neg Mannitol:  neg Salicin:  neg Sorbitol:  neg Starch:  w(+) Thr:  neg Lactate:  neg Pyruvate:  +
    ENZYME ACTIVITY
    Enzymes: General Enzymes: Carbohydrate Enzymes: Protein Enzymes: Arylamidases Enzymes: Esters/fats
    DNAse:  + Lecithinase:  neg Lipase:  neg
    METABOLITES - PRODUCTION & USE
    Fuel Usable Metabolites Metabolites Released Special Products Compounds Produced

    		Acetate:  + Butyrate:  + Butanol:  + H2S:  + H2:  + Indole:  +
    ANTIBIOTICS ℞
    Penicillins & Penems (μg/mL) Cephalosporins (μg/mL) Aminoglycosides (μg/mL) Macrolides (μg/mL) Quinolones (μg/mL)
    penicillin_G:  S(MIC50): 0.125, MIC90: 0.5, RNG: (0.02-0.5)
    piper-taz:  S(MIC50): 0.25, MIC90: 2, RNG: (0.02-2)
    imipenem:  S(MIC50): 0.125, MIC90: 1, RNG: (0.015-2)
    fidaxomicin:  S(0.03)
    quin-dalf:  S(MIC50): 0.25, MIC90: 0.5, RNG: (0.125-0.5)
    linezolid:  S(MIC50): 1, MIC90: 4, RNG: (0.5-4)
    Tetracyclines (μg/mL) Vancomycin Class (μg/mL) Polypep/ketides (μg/mL) Heterocycles (μg/mL) Other (μg/mL)
    dalbavancin:  S(MIC50): 0.125, MIC90: 0.5, RNG: (≤0.015-1)
    vancomycin:  S(MIC50): 0.5, MIC90: 2, RNG: (0.25->32)
    metronidazole:  S(MIC50): 0.5, MIC90: 2, RNG: (0.02-2)
    daptomycin:  Var(MIC50): 1, MIC90: 8, RNG: (0.06-16)

    References

    SPECIFIC REFERENCES FOR CLOSTRIDIUM FALLAX
  • Hall1922 - Differentiation and identification of the sporulating anaerobes.
  • Rainey2011aBergey - Bergey's manual of systematic bacteriology. Vol. 3, The Firmicutes. Family Clostridiaceae, Genus I. Clostridium - Cluster I
  • Goldstein2014 - Comparative in vitro activities of SMT19969, a new antimicrobial agent, against 162 strains from 35 less frequently recovered intestinal Clostridium species: implications for Clostridium difficile recurrence.
  • ...............................
    • GUT MICROBIOME COMPILATIONS AND METASTUDIES FOR CLOSTRIDIUM FALLAX
  • Byrd2020 - Stability and dynamics of the human gut microbiome and its association with systemic immune traits.
  • Finegold1974 - Effect of diet on human fecal flora: comparison of Japanese and American diets
  • Lagier2016 - Culture of previously uncultured members of the human gut microbiota by culturomics.
  • RajilicStojanovic2014 - The first 1000 cultured species of the human gastrointestinal microbiota.
  • ...............................
    • GENERAL REFERENCES FOR CLOSTRIDIUM FALLAX
  • Ludwig2009 - Revised road map to the phylum Firmicutes.
    • Added: April 08, 2021