The key difference between tryptone and peptone is that tryptone is a water-soluble mixture of peptides created by the digestion of casein by the enzyme trypsin, while peptone is a water-soluble mixture of polypeptides and amino acids created by the partial acid or enzymatic hydrolysis of protein.
The hydrolysis of complex proteins aims to break down the peptide bonds in order to increase free amino acid and carboxyl groups. The resultant protein hydrolysate is more soluble and digestible. This process is more common in the human digestion process. Therefore, tryptone and peptone are two types of protein hydrolysates.
CONTENTS
1. Overview and Key Difference
2. What is Tryptone
3. What is Peptone
4. Similarities – Tryptone and Peptone
5. Tryptone vs Peptone in Tabular Form
6. Summary – Tryptone vs Peptone
What is Tryptone?
Tryptone is a water mixture of peptides formed by the digestion of casein by the enzyme called trypsin. The pancreatic enzyme digestion of casein in milk produces tryptone. Casein is the main milk protein and is a rich source of the amino acid nitrogen. Moreover, amongst all amino acids in casein, tryptophan is present in high concentration.
Due to its nutritional properties, tryptone is added to culture media as an accelerator in microorganism culturing. It increases the yield of organisms, and it is recommended when the rapid growth of microorganisms is required. In microbiology, tryptone is commonly used to produce lysogeny broth (LB) in order to grow E. coli. Tryptone in this culture media provides a source of amino acids for the growing bacteria. Furthermore, tryptone is similar to casamino acids. Both are digests of casein protein. But casamino acids are produced by acid hydrolysis and normally contain only free amino acids and a few peptide chains. On the other hand, tryptone is the product of incomplete enzymatic hydrolysis that contains some oligopeptides. In addition to that, tryptone is a component of some germination media used in plant propagation.
What is Peptone?
Peptone is a water-soluble mixture of polypeptides and amino acids formed by the partial acid or enzymatic hydrolysis of protein. It is not coagulated by heat. Peptone usually contains polypeptides and amino acids, and it provides a readily available source of nitrogen and mineral. Therefore, peptone can be used for the growth of bacteria in microbiology. Moreover, peptones are used in culture media to grow different kinds of microorganisms. Peptones are also well-suited blood media. Therefore, it can be used for haemolytic studies such as about pneumococci or streptococci.
Furthermore, peptones are also used as a nutrient for industrial fermentation processes such as vaccine production. In industrial vaccine production, the usage of peptones can help to overcome the so-called lag phase. Peptones are readily available in spray-dried powder form, syrup form, or solid form. Moreover, peptones should be stored in their original form and in tight containers at a cool and dry place in order to use them for a long period of time (2 to 3 years).
What are the Similarities Between Tryptone and Peptone?
- Tryptone and peptone are two types of protein hydrolysates.
- Both are produced from complex proteins.
- They can be produced from enzymatic digestion or hydrolysis.
- Both provide a readily available source of nitrogen.
- They are produced in the human digestion process.
- Both are water-soluble.
- They are not heat-coagulated.
What is the Difference Between Tryptone and Peptone?
Tryptone is a water-soluble mixture of peptides formed by the digestion of casein by the enzyme trypsin, while peptone is a water-soluble mixture of polypeptides and amino acids formed by the partial acid or enzymatic hydrolysis of protein. Thus, this is the key difference between tryptone and peptone. Furthermore, tryptone contains oligopeptides, while peptone contains polypeptides and amino acids.
The below infographic presents the differences between tryptone and peptone in tabular form for side-by-side comparison.
Summary – Tryptone vs Peptone
Tryptone and peptone are two types of protein hydrolysates that are produced by the complex protein hydrolysis process. Both these protein hydrolysates are water-soluble. However, tryptone is a water-soluble mixture of peptides produced by the digestion of casein by the enzyme trypsin, while peptone is a water-soluble mixture of polypeptides and amino acids produced by the partial acid or enzymatic hydrolysis of protein. So, this summarizes the difference between tryptone and peptone.
Reference:
1. “Tryptone” An Overview | ScienceDirect Topics.
2. Davami, Fatemeh, et al. “Effects of Peptone Supplementation in Different Culture Media on Growth, Metabolic Pathway and Productivity of Cho DG44 Cells; a New Insight into Amino Acid Profiles.” Iranian Biomedical Journal, U.S. National Library of Medicine.
Image Courtesy:
1. “Listeria monocytogenes on Tryton soya yeast extract agar” By Internet Archive Book Images (Public Domain) via Flickr
2. “Image from page 71 of “Elements of biology, with special reference to their rôle in the lives of animals” (1933)” By Daizy John – Own work (CC BY 4.0) via Commons Wikimedia