What is the Difference Between E Coli and Serratia Marcescens?

E. coli and Serratia marcescens are both gram-negative, rod-shaped bacteria, but they belong to different families and have distinct characteristics:

E. coli:

• Belongs to the Enterobacteriaceae family.
• Found in the human gastrointestinal tract and forms an important part of the gut microbiota.
• Can be non-motile or motile.
• Does not produce any pink or red discoloration.
• Cannot hydrolyze casein.
• Does not grow in a citrate medium (citrate negative).
• Part of faecal flora and acts as a bioindicator organism.

Serratia marcescens:

• Belongs to the Yersiniaceae family.
• Found in damp environments like water bodies and soil, and commonly seen in bathrooms.
• Is motile.
• Produces pink or pinkish-orange film on shampoo and soap residues.
• Can hydrolyze casein.
• Can utilize a citrate medium (citrate positive).
• Is not a part of faecal flora.

E. coli is a coliform bacterium that is normally found in the intestines of healthy people and animals, while S. marcescens is an opportunistic pathogen that can cause hospital-acquired infections, including urinary tract infections and wound infections.

Comparative Table: E Coli vs Serratia Marcescens

Here is a table comparing the differences between E. coli and Serratia marcescens:

Both E. coli and Serratia marcescens are gram-negative bacteria belonging to the order Enterobacteriales and are facultative anaerobic organisms. However, they have different locations, motility, and pathogenic potentials. While E. coli is a part of the human gut microbiota and can cause various infections, Serratia marcescens is found in damp environments and is commonly involved in hospital-acquired infections.