The key difference between Coliforms and Enterobacteriaceae is that the Coliforms are a group of grams negative, rod-shaped and lactose fermenting bacteria while Enterobacteriaceae is a large family of grams negative bacteria.
Indicator organisms are the organisms that have the use as signs to indicate a particular situation. They indicate the presence of something which is not normal. Coliforms and Enterobacteriaceae are indicator bacteria that indicate the sign of the sanitary quality of food and water and also indicate the conditions of the environment. Moreover, all Coliforms belong to Enterobacteriaceae, but all Enterobacteriaceae members are not Coliforms.
CONTENTS
1. Overview and Key Difference
2. What are Coliforms
3. What are Enterobacteriaceae
4. Similarities Between Coliforms and Enterobacteriaceae
5. Side by Side Comparison – Coliforms vs Enterobacteriaceae in Tabular Form
6. Summary
What are Coliforms?
Coliforms is a general term that refers to a group of grams negative, rod-shaped, non-spore forming, motile or non-motile and lactose fermenting bacteria. It consists of many bacterial genera including Citrobacter, Enterobacter, Escherichia, and Klebsiella, etc. When coliforms ferment lactose at 37 0C, they produce gas and acids. Therefore, the production of gas and acids are the results used to evaluate their presence in laboratory testing. Moreover, coliforms live naturally in soil, water, and also in human and other animals’ intestines. Hence, coliforms are two major groups; faecal coliforms and non faecal coliforms.
Figure 01: Coliforms
This group is really important in assessing the sanitary quality of water and food. This is because they are the indicator organisms that are mostly used in sanitary measurements. Among the Coliforms, fecal coliforms and E. coli are the most specific indicator organisms tested in the assurance of food and water quality. Their presence indicates the potential presence of pathogens in food and water.
What are Enterobacteriaceae?
Enterobacteriaceae is a large family of grams negative bacteria. There are many bacterial genera (about 20 genera) which belong to family Enterobacteriaceae such as Salmonella, Escherichia coli, Yersinia, Klebsiella, Proteus, Enterobacter, Serratia, Citrobacter and Shigella, etc. Some are disease-causing while some are not.
Figure 02: Enterobacteriaceae
Moreover, all the members of Enterobacteriaceae are facultative anaerobes. They are of rod-shape and live in soil and water. Also, they naturally live in the human and animals intestines. These bacteria can ferment glucose.
What are the Similarities Between Coliforms and Enterobacteriaceae?
- Coliforms and Enterobacteriaceae are good indicators of water pollution.
- Both include grams negative bacteria.
- Coliforms and some Enterobacteriaceae can ferment sugars.
- They live in the same environment.
- They cause food and water-borne diseases.
- Both Coliforms and Enterobacteriaceae grow under similar conditions.
- Both types are grams negative and rod-shaped.
- Coliforms and Enterobacteriaceae are mostly facultative anaerobes.
- They are found in soil, water and human and other animals’ intestines.
What is the Difference Between Coliforms and Enterobacteriaceae?
Enterobacteriaceae is a large family of grams negative bacteria. Coliforms are a group of grams negative bacteria which are lactose fermenting. Coliforms belong to Enterobacteriaceae. Hence, all coliforms are members of Enterobacteriaceae. But not all Enterobacteriaceae are coliforms. Coliforms ferment lactose and produce acids and gas. Enterobacteriaceae ferment glucose and some ferment lactose.
Summary – Coliforms vs Enterobacteriaceae
Coliforms and Enterobacteriaceae are specific indicator organisms used in microbiology. They signal the presence of pathogens in food and water. Hence they are used to assess the quality of food, water and the environment. Coliforms are lactose fermenting while Enterobacteriaceae are mainly glucose fermenting. Both are grams negative bacteria. This is the difference between Coliforms and Enterobacteriaceae.
Reference:
1.“Enterobacteriaceae.” Egyptian Journal of Medical Human Genetics, Elsevier. Available here
2.“Enterobacteriaceae Family: Common Characteristics -.” Home -, 9 Dec. 2016. Available here
Image Courtesy:
1.’E coli at 10000x, original’By Photo by Eric Erbe (Public Domain) via Commons Wikimedia
2.’Enterobacteriaceae Antigen’By JrPolderivative work (CC BY-SA 3.0) via Commons Wikimedia