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The Info List - Firmicutes



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The FIRMICUTES ( Latin
Latin
: _firmus_, strong, and _cutis_, skin, referring to the cell wall) are a phylum of bacteria , most of which have Gram-positive cell wall structure. A few, however, such as _ Megasphaera _, _ Pectinatus _, _ Selenomonas _ and _ Zymophilus _, have a porous pseudo-outer membrane that causes them to stain Gram-negative . Scientists once classified the Firmicutes
Firmicutes
to include all Gram-positive bacteria, but have recently defined them to be of a core group of related forms called the low-G+C group, in contrast to the Actinobacteria . They have round cells, called cocci (singular coccus), or rod-like forms (bacillus).

Many Firmicutes
Firmicutes
produce endospores , which are resistant to desiccation and can survive extreme conditions. They are found in various environments, and the group includes some notable pathogens. Those in one family, the heliobacteria , produce energy through photosynthesis . Firmicutes
Firmicutes
play an important role in beer, wine, and cider spoilage.

CONTENTS

* 1 Classes * 2 Phylogeny * 3 Genera * 4 Health implications * 5 Laboratory detection * 6 References * 7 External links

CLASSES

The group is typically divided into the Clostridia , which are anaerobic , the Bacilli , which are obligate or facultative aerobes , and the Mollicutes
Mollicutes
, which are parasites.

On phylogenetic trees , the first two groups show up as paraphyletic or polyphyletic , as do their main genera, _ Clostridium _ and _ Bacillus
Bacillus
_.

PHYLOGENY

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI) and the phylogeny is based on 16S rRNA-based LTP release 111 by The All-Species Living Tree Project

? Thermodesulfobiaceae

? Synergistaceae { Clostridiales Family XV Incertae Sedis}

Firmicutes
Firmicutes
s. s.

?_ Clostridium thermoamylolyticum _ ♠ Katkocin et al. 1985

_ Thermaerobacter _

_ Caldicellulosiruptor _

Thermoanaerobacteraceae

_ Thermanaeromonas toyohensis _

_ Dictyoglomus _

Thermoanaerobacterales Unnamed clade I (incl. _Fervidicola _)

Thermoanaerobacterales Unnamed clade II

_Gelria glutamica _

Clostridiales Family XVIII Incertae Sedis

_Sulfobacillus _

Clostridia s.s. (incl. _Thermolithobacter _, Negativicutes border-left:1px solid;vertical-align:top;text-align:center;">

Bacilli (incl. Erysipelotrichia vertical-align:top;text-align:center;">

Notes: ♠ Strains found at the National Center for Biotechnology Information (NCBI) but not listed in the List of Prokaryotic names with Standing in Nomenclature LPSN

GENERA

More than 274 genera were considered as of 2016 to be within the Firmicutes
Firmicutes
phylum, notable genera of Firmicutes
Firmicutes
include:

BACILLI, ORDER BACILLALES

* _ Bacillus
Bacillus
_ * _ Listeria _ * _ Staphylococcus _

BACILLI, ORDER LACTOBACILLALES

* _ Lactobacillus _ * _ Leuconostoc _

CLOSTRIDIA

* _ Acetobacterium _ * _ Clostridium _ * _ Eubacterium _ * _ Heliobacteria _ * _Heliospirillum _ * _ Megasphaera _ * _ Pectinatus _ * _ Selenomonas _ * _ Zymophilus _ * _ Sporohalobacter _ * _ Sporomusa _

ERYSIPELOTRICHIA

* _Erysipelothrix _

HEALTH IMPLICATIONS

Firmicutes
Firmicutes
make up the largest portion of the mouse and human gut microbiome. The division Firmicutes
Firmicutes
as part of the gut flora has been shown to be involved in energy resorption, and potentially related to the development of diabetes and obesity .

Firmicutes
Firmicutes
spp. are part of a normal, healthy placental microbiome . See also: Infectobesity

Presence of _ Christensenella _ (Firmicutes, in class Clostridia), isolated from human faeces , has been found to correlate with lower body mass index .

LABORATORY DETECTION

The presence of Firmicutes
Firmicutes
can be reliably detected with polymerase chain reaction (PCR) techniques.

REFERENCES

* ^ Gibbons, N. E. & Murray, R. G. E. 1978. Proposals concerning the higher taxa of bacteria. _Int J Syst Bacteriol_ 28:1–6, (PDF) * ^ Murray, R.G.E. (1984). The higher taxa, or, a place for everything...?. In: N.R. Krieg & J.G. Holt (ed.) _ Bergey's Manual of Systematic Bacteriology_, vol. 1, The Williams & Wilkins Co., Baltimore, p. 31-34. * ^ "Firmicutes" at _Dorland\'s Medical Dictionary _ * ^ Wolf M, Müller T, Dandekar T, Pollack JD (May 2004). "Phylogeny of Firmicutes
Firmicutes
with special reference to Mycoplasma (Mollicutes) as inferred from phosphoglycerate kinase amino acid sequence data". _Int. J. Syst. Evol. Microbiol._ (Comparative Study). 54 (Pt 3): 871–5. PMID 15143038 . doi :10.1099/ijs.0.02868-0 . * ^ J.P. Euzéby. "Firmicutes". List of Prokaryotic names with Standing in Nomenclature (LPSN). Archived from the original on January 27, 2013. Retrieved 2013-03-20. * ^ Sayers; et al. "Firmicutes". National Center for Biotechnology Information (NCBI) taxonomy database. Retrieved 2013-03-20. * ^ All-Species Living Tree Project ."16S rRNA-based LTP release 111 (full tree)" (PDF). Silva Comprehensive Ribosomal RNA Database . Retrieved 2013-03-20. * ^ Ley RE, Peterson DA, Gordon JI (2006). "Ecological and evolutionary forces shaping microbial diversity in the human intestine". _Cell_ (Review). 124 (4): 837–48. PMID 16497592 . doi :10.1016/j.cell.2006.02.017 . * ^ Ley RE, Turnbaugh PJ, Klein S, Gordon JI (2006). "Microbial ecology: human gut microbes associated with obesity". _Nature_ (Clinical Trial). 444 (7122): 1022–3. PMID 17183309 . doi :10.1038/4441022a . * ^ Henig, Robin Marantz (2006-08-13). "Fat Factors". New York Times Magazine. Retrieved 2008-09-28. * ^ Ley RE, Bäckhed F, Turnbaugh P, Lozupone CA, Knight RD, Gordon JI (August 2005). " Obesity alters gut microbial ecology". _Proc. Natl. Acad. Sci. U.S.A._ (Research Support). 102 (31): 11070–5. PMC 1176910  _. PMID 16033867 . doi :10.1073/pnas.0504978102 . Retrieved 2008-09-28. * ^ Komaroff AL. The Microbiome and Risk for Obesity and Diabetes. JAMA. Published online December 22, 2016. doi:10.1001/jama.2016.20099 * ^ Mor, Gil; Kwon, Ja-Young (2015). "Trophoblast-microbiome interaction: a new paradigm on immune regulation". American Journal of Obstetrics and Gynecology_. 213 (4): S131–S137. ISSN 0002-9378 . PMID 26428492 . doi :10.1016/j.ajog.2015.06.039 . * ^ Todar, K. "Pathogenic _E. coli_". _Online Textbook of Bacteriology_. University of Wisconsin–Madison Department of Bacteriology. Retrieved 2007-11-30. * ^ Goodrich, Julia K.; Waters, Jillian L.; Poole, Angela C.; Sutter, Jessica L.; Koren, Omry; Blekhman, Ran; Beaumont, Michelle; Van Treuren, William; Knight, Rob; Bell, Jordana T.; Spector, Timothy D.; Clark, Andrew G.; Ley, Ruth E. (2014). "Human Genetics Shape the Gut Microbiome". _Cell_. 159 (4): 789–799. ISSN 0092-8674 . doi :10.1016/j.cell.2014.09.053 . _ * ^ Haakensen M, Dobson CM, Deneer H, Ziola B (July 2008). "Real-time PCR detection of bacteria belonging to the Firmicutes Phylum". Int. J. Food Microbiol._ (Research Support). 125 (3): 236–41. PMID 18501458 . doi :10.1016/j.ijfoodmicro.2008.04.002 . Retrieved 2008-09-28.

EXTERNAL LINKS

* Phylum

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