digplanet beta 1: Athena
Share digplanet:

Agriculture

Applied sciences

Arts

Belief

Business

Chronology

Culture

Education

Environment

Geography

Health

History

Humanities

Language

Law

Life

Mathematics

Nature

People

Politics

Science

Society

Technology

Not to be confused with Enteric bacteria.
Enterobacteriaceae
Citrobacter freundii.jpg
Citrobacter freundii, one member of the family
Scientific classification
Domain: Bacteria
Phylum: Proteobacteria
Class: Gammaproteobacteria
Order: Enterobacteriales
Family: Enterobacteriaceae
Rahn, 1937

The Enterobacteriaceae are a large family of Gram-negative bacteria that includes, along with many harmless symbionts, many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella and Shigella. Other disease-causing bacteria in this family include Proteus, Enterobacter, Serratia, and Citrobacter. This family is the only representative in the order Enterobacteriales of the class Gammaproteobacteria in the phylum Proteobacteria.[1] Phylogenetically, in the Enterobacteriales, several peptidoglycan-less insect endosymbionts[citation needed] form a sister clade to the Enterobacteriaceae, but as they are not validly described, this group is not officially a taxon; examples of these species are Sodalis, Buchnera, Wigglesworthia, Baumannia cicadellinicola and Blochmannia, but not former Rickettsias.[2] Members of the Enterobacteriaceae can be trivially referred to as enterobacteria or "enteric bacteria",[3] as several members live in the intestines of animals. In fact, the etymology of the family is enterobacterium with the suffix to designate a family (aceae) — not after the genus Enterobacter (which would be "Enterobacteraceae")— and the type genus is Escherichia.

Characteristics[edit]

Members of the Enterobacteriaceae are rod-shaped, and are typically 1-5 μm in length. They appear as small grey colonies on blood agar. Like other proteobacteria, enterobacteria have Gram-negative stains,[4] and they are facultative anaerobes, fermenting sugars to produce lactic acid and various other end products. Most also reduce nitrate to nitrite, although exceptions exist (e.g. Photorhabdus). Unlike most similar bacteria, enterobacteria generally lack cytochrome C oxidase, although there are exceptions (e.g. Plesiomonas shigelloides). Most have many flagella used to move about, but a few genera are nonmotile. They are not spore-forming. Catalase reactions vary among Enterobacteriaceae.

Many members of this family are a normal part of the gut flora found in the intestines of humans and other animals, while others are found in water or soil, or are parasites on a variety of different animals and plants. Escherichia coli is one of the most important model organisms, and its genetics and biochemistry have been closely studied.

Most members of Enterobacteriaceae have peritrichous, type I fimbriae involved in the adhesion of the bacterial cells to their hosts. Some enterobacteria produce endotoxins. Endotoxins reside in the cell cytoplasm and are released when the cell dies and the cell wall disintegrates. Some members of the Enterobacteriaeceae produce endotoxins that, when released into the bloodstream following cell lysis, cause a systemic inflammatory and vasodilatory response. The most severe form of this is known as endotoxic shock, which can be rapidly fatal.

Identification[edit]

To identify different genera of Enterobacteriaceae, a microbiologist may run a series of tests in the lab. These include:[5]

  • Phenol red
  • Tryptone broth
  • Phenylalanine agar for detection of production of deaminase, which converts phenylalanine to phenylpyruvic acid
  • Methyl red or Voges-Proskauer tests depend on the digestion of glucose. The methyl red tests for acid endproducts. The Voges Proskauer tests for the production of acetylmethylcarbinol.
  • Catalase test on nutrient agar tests for the production of catalase enzyme, which splits hydrogen peroxide and releases oxygen gas.
  • Oxidase test on nutrient agar tests for the production of the enzyme oxidase, which reacts with an aromatic amine to produce a purple color.
  • Nutrient gelatin tests to detect activity of the enzyme gelatinase.

In a clinical setting, three species make up 80 to 95% of all isolates identified. These are Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis.

Antibiotic resistance[edit]

Several Enterobacteriaceae strains have been isolated which are resistant to antibiotics including carbapenem, which are often claimed as "the last line of antibiotic defense" against resistant organisms. For instance, some Klebsiella pneumoniae strains are carbapenem resistant.[6]

Examples/classification[edit]

The following inexhaustive list details bacterial genera classified as members of Enterobacteriaceae.

Genera[edit]

References[edit]

  1. ^ Don J. Brenner, Noel R. Krieg, James T. Staley (July 26, 2005) [1984 (Williams & Wilkins)]. George M. Garrity, ed. The Gammaproteobacteria. Bergey's Manual of Systematic Bacteriology 2B (2nd ed.). New York: Springer. p. 1108. ISBN 978-0-387-24144-9. British Library no. GBA561951. 
  2. ^ Williams, K. P.; Gillespie, J. J.; Sobral, B. W. S.; Nordberg, E. K.; Snyder, E. E.; Shallom, J. M.; Dickerman, A. W. (2010). "Phylogeny of Gammaproteobacteria". Journal of Bacteriology 192 (9): 2305–2314. doi:10.1128/JB.01480-09. PMC 2863478. PMID 20207755.  edit
  3. ^ http://inst.bact.wisc.edu/inst/index.php?module=book&type=user&func=displayarticle&art_id=268
  4. ^ "Dorlands Medical Dictionary:Enterobacteriaceae". 
  5. ^ MacFaddin, Jean F. Biochemical Tests for Identification of Medical Bacteria. Williams & Wilkins, 1980, p 441.
  6. ^ Centers for Disease Control and Prevention - Klebsiella Quotation: "Increasingly, Klebsiella bacteria have developed antimicrobial resistance, most recently to the class of antibiotics known as carbapenems."

External links[edit]

  • Enterobacteriaceae genomes and related information at PATRIC, a Bioinformatics Resource Center funded by NIAID
  • Evaluation of new computer-enhanced identification program for microorganisms: adaptation of BioBASE for identification of members of the family Enterobacteriaceae [1]
  • Brown, A.E. (2009). Benson's microbiological applications: laboratory manual in general microbiology. New York: McGraw- Hill.

Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Enterobacteriaceae — Please support Wikipedia.
This page uses Creative Commons Licensed content from Wikipedia. A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia.
2025 videos foundNext > 

https://youtube.com/devicesupport

Bacteriology 8.1: Introduction to Enterobacteriaceae

www.mededuco.com www.facebook.com/mededuco.

Medical Video Lecture: Enterobacteriaceae Classification,Microbiology

Prepare for USMLE,UK,CANADIAN,AUSTRALIAN, NURSING & OTHER MEDICAL BOARD examinations around the globe with us. Understand the basics, concepts and how to answer wisely and score ...

2.17. Enterobacteriaceae-I - Medical Microbiology

See the entire series of Medical Microbiology, Immumology and Parasitology lectures - http://goo.gl/my7pr. Visit our website: http://doctorprodigious.wordpress.com . Visit our website: http://doct...

Klebsiella, Enterobacter, Serratia [HD] - SketchyMicro USMLE Microbiology Review

Website: http://www.SketchyMicro.com Twitter: @SketchyMicro Facebook: http://www.facebook.com/SketchyMicro "Urinary Tract Extinction" Illustration: Bryan L Narration: Andrew B Created By:...

Enterobacteriaceae ( Escherichia coli _ Klebsiella pneumoniae).mp4

Enterobacteriaceae ( Escherichia coli _ Klebsiella pneumoniae).mp4.

Pre Lab Lecture Enterobacteriaceae

Description.

The Enterobacteriaceae Family

This video discusses the gamma group proteobacteria - the enterobacteriaceae family. All content is known to be true by me, but if you see any mistakes or any accidental copyright infringement,...

Familia Enterobacteriaceae parte 1

Tests for Enterobacteriaceae;جامعة الباحة | د.محمد آل قمبر | تحاليل التفريق بين بكتيريا الأمعائيات

Enterobacteriaceae, coliforms or enteric bacteria, biochemical tests describing IMViC tests. That is, Indole Methyl Red-Voges Proskauer citrate and urease tests. These tests are used to differentia...

2025 videos foundNext > 

2894 news items

Tech Times

Washington Post
Fri, 24 Apr 2015 12:40:24 -0700

We're talking about front-line antibiotics used to treat various infections, including multidrug-resistant bacteria such as MRSA, carbapenem-resistant Enterobacteriaceae and clostridium difficile. In some cases, the only drug available against a ...
 
Journal of Clinical Microbiology
Thu, 16 Apr 2015 08:50:21 -0700

The CLSI reduced the cefepime Enterobacteriaceae susceptibility breakpoint and introduced the susceptible-dose-dependent (S-DD) category. In this study, MICs were determined for a Gram-negative collection to assess the impact of this change.

Kansas City Star

Huffington Post
Thu, 19 Feb 2015 06:42:44 -0800

Seven patients are infected and almost 200 others were exposed to a potentially fatal group of "superbugs" carbapenem-resistant Enterobacteriaceae, or CRE, at Ronald Reagan UCLA Medical Center. The bug may have played a role in the deaths of two ...
 
Infection Control Today
Fri, 24 Apr 2015 06:18:45 -0700

Already following strict disinfection routines, St. Vincent Healthcare is now also using germ-killing robot Tru-D SmartUVC to eliminate harmful germs, like Ebola, methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant ...
 
Science 2.0
Thu, 23 Apr 2015 20:18:09 -0700

One might think that perhaps physicians at Columbia might want to concentrate more on, let's say, Alzheimer's disease, pancreatic cancer, schizophrenia, or Carbapenem-resistant enterobacteriaceae infections—all of which are not only incurable, but ...
 
Daily Bruin
Thu, 23 Apr 2015 00:39:23 -0700

On Feb. 18, the UCLA Health system issued a statement saying more than 100 people may have been infected with the superbug, or carbapenem-resistant Enterobacteriaceae – commonly known as CRE – following medical procedures that used Olympus ...

Medscape

Medscape
Thu, 23 Apr 2015 03:18:45 -0700

Most of the shortages involved broad-spectrum antibiotics, and almost half (46%) involved antibiotics used to treat high-risk pathogens, including Clostridium difficile, carbapenem-resistant Enterobacteriaceae, methicillin-resistant Staphylococcus ...

Monthly Prescribing Reference

PR Newswire (press release)
Thu, 23 Apr 2015 05:00:00 -0700

AVYCAZ demonstrated in vitro activity against Enterobacteriaceae in the presence of some beta-lactamases and extended-spectrum beta-lactamases (ESBLs) of the following groups: TEM, SHV, CTX-M, Klebsiella pneumoniae carbapenemase (KPCs), AmpC ...
Loading

Oops, we seem to be having trouble contacting Twitter

Support Wikipedia

A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia. Please add your support for Wikipedia!

Searchlight Group

Digplanet also receives support from Searchlight Group. Visit Searchlight