Enterococcus Faecalis: A Guide, Biochemical Test And Identification Results

Enterococcus faecalis is a bacterium that is found in the human digestive tract.

It is not harmful to humans unless the bacteria are transferred to another part of the body – this can sometimes happen during surgery.

Enterococcus Faecalis: A Guide, Biochemical Test And Identification Results

It is a Gram-positive, commensal bacterium that was formerly classified as part of the group D Streptococcus system.

Symbioflor1 and EF-2001 strains of Enterococcus faecalis can be given as probiotics, partly because they are not drug-resistant like other strains of Enterococcus faecalis.

When transferred to another part of the body, Enterococcus faecalis becomes an opportunistic pathogen.

It can cause a series of dangerous infections and is particularly problematic because most strains are drug-resistant.

These transfers typically happen in hospitals but can occur when wounds are left open and untreated.

If you have an already compromised immune system, Enterococcus faecalis infections can be deadly, so if infected you should seek treatments as quickly as possible.

In this article, we are going to take a look at Enterococcus faecalis – how it affects the human body, its biochemical test results, and how it can be treated.

Enterococcus faecalis:

  • Domain: Bacteria
  • Phylum: Bacillota
  • Class: Bacilli
  • Order: Lactobacillales
  • Family: Enterococcaceae
  • Genus: Enterococcus
  • Species: E. faecalis

Biochemical Tests And Identification Results

Enterococcus faecalis is a Gram-positive, commensal bacterium. It is non-sporing, non-motile, and cocci shaped.

Enterococcus Faecalis: A Guide, Biochemical Test And Identification Results

All test results not mentioned were not applicable.

Characteristic Results

Positive (+ve) Characteristics

  • Gram Staining
  • VP
  • Urease
  • Nitrate Reduction
  • PYR

Variable Characteristics:

  • Gelatin Hydrolysis
  • Hemolysis (Alfa/Beta/Gamma) – Alpha or Beta

Negative (-ve) Characteristics:

  • Catalase
  • Oxidise
  • Indole
  • Citrate
  • H2S
  • Pigment

Fermentation Results

Positive (+ve) Results

  • Glucose
  • Hippurate
  • Lactose
  • *Fructose (positive d-fructose)
  • Maltose
  • Mannitol
  • *Mannose (positive d-mannose)
  • Ribose
  • Sorbitol
  • Sucrose

Negative (-ve) Results

  • Arabinose
  • Insuline
  • *Raffinose (negative d-Raffinose)

Enzymatic Reactions Results

Positive (+ve) Results

  • Arginine dehydrolase

Variable Results

  • Alkaline Phosphatase

No negative results. All other results are not applicable.

Enterococcus Faecalis

Enterococcus faecalis is one of 18 Enterococci bacteria species that live in the human digestive tract.

It is the 2nd most abundant of the Enterococci and can also be found in the mouth and the vagaina.

All Enterococci are incredibly resilient – they can survive in a wide range of temperatures, as well as in salty and acidic environments.

Enterococcus Faecalis

A lot of Enterococcus faecalis are resistant to antibiotics which is what makes them so dangerous when they infect other areas of the body.

In the gut, the mouth, and the vagina these bacteria are harmless.


When it was first discovered, the Enterococcus faecalis bacteria were classified as a group D Streptococcus system.

It was originally discovered in 1906, by Andrewes and Horder.

However, when the DNA of these bacteria was able to be fully mapped in 1984, scientists discovered that the bacteria were more complex than originally thought, and they made the choice to reclassify and rename the Enterococci group.

The scientists who made this choice were Schleifer and Kilpper-Bälz. The Enterococcus faecalis bacteria has 3.22 million base pairs in its genes.

Infection – Dangers, Symptoms, Treatments

While the Enterococci group is mostly harmless inside the human gut, when it is transferred to other areas of the body it transforms into an opportunistic pathogen.

When they make it into a part of the body they are not meant to be in they can cause a whole range of infections:

  • Urinary Tract Infections
  • Meningitis
  • Bacteremia – a dangerous infection in the blood
  • Endocarditis – 10% of the people who get this infection get it from Enterococci bacteria
  • Periodontitis
  • Wound infections


Enterococci bacteria are found in feces, so these infections are most commonly passed around because of poor hygiene practices.

If they get on things that are not washed properly they can be transferred to phones, keyboards, doorknobs, and even onto other people when you touch them.

However, these types of bacteria are most commonly spread in hospitals. If a healthcare expert does not wash their hands properly they can pass the bacteria on to multiple patients in a day.

Also not cleaning hospital equipment correctly can cause outbreaks of many types of infection in hospitals – most notably MRSA and Enterococcus faecalis.

This can be particularly dangerous when immunocompromised patients are being cared for in the hospital.


Because Enterococci bacteria can cause a huge range of infections, there is an even longer list of symptoms.

However, the most common symptoms of this kind of bacteria infection include:

  • Stiff joints – especially neck and shoulders
  • Urination becomes painful
  • Swollen and bleeding gums
  • Tiredness
  • Diaherra
  • Vomiting
  • Difficulty breathing
  • Pain when breathing
  • High temperature or fever
  • Chills
  • Sore eyes
  • Headache
  • Stomach pain


Once an Enterococcus faecalis infection is detected, you will be prescribed antibiotics.

However, doctors have to be careful to prescribe the right kind of antibiotic as many Enterococci strains are resistant to medication.

This means they can function well in the gut, but they are more difficult to get rid of than a typical infection.

If you are immunocompromised then you will want to see your doctor as soon as you realize that you are unwell.

People will damage immune systems – like people who have cancer, diabetes, and autoimmune disease like Crohn’s disease – are at the greatest risk of developing serious infections after coming into contact with Enterococcus faecalis.

The best way to avoid these infections is to regularly wash your hands, as well as disinfecting the items that you touch regularly – like your phone, keys, and laptop.


Enterococcus faecalis is one of the 18 types of Enterococci bacteria that live in the gut. It is one of the most common of these bacteria.

It is an important bacteria that places a key role in our digestive system. Because it lives in our gut it is hardy and has evolved to cope in many different environments.

However, if this bacteria gets into another part of the body then it can cause serious and life-threatening infections to develop.

The best way to avoid spreading this bacteria is to regularly wash your hands.

Jennifer Dawkins

Leave a Comment

Your email address will not be published. Required fields are marked *