API Acid Protease CAS 9025-49-4

Name

Acid Protease

CAS number

9025-49-4

Description

1. Definition and Classification

Acid protease is a type of protease that functions optimally under acidic conditions. It belongs to the family of hydrolytic enzymes, which break down peptide bonds in proteins. Based on its structure and catalytic mechanism, it can be classified into different subgroups such as pepsin - like proteases and aspartic proteases. Pepsin - like proteases are mainly found in the stomach and play a crucial role in the initial digestion of dietary proteins. Aspartic proteases have a characteristic structure with two aspartic acid residues in the active site that are involved in the catalytic process.

2. Structure

The structure of acid protease typically consists of a single polypeptide chain. In the case of aspartic proteases, the active site contains two aspartic acid residues that work together to hydrolyze peptide bonds. These residues act as catalytic dyads and are usually located in a cleft or pocket within the enzyme's three - dimensional structure. The overall conformation of the enzyme is designed to recognize and bind to specific protein substrates. The tertiary structure of acid protease is stabilized by various forces such as hydrogen bonds, disulfide bridges, and hydrophobic interactions.

3. Function

Digestion: In the digestive system, acid protease, such as pepsin, is secreted in the stomach. The acidic environment of the stomach (pH around 1.5 - 3.5) activates these enzymes. They begin the process of protein digestion by cleaving the large polypeptide chains of dietary proteins into smaller peptides. This is a crucial step in the overall process of nutrient absorption, as smaller peptides are more easily processed by other digestive enzymes further down the digestive tract.

Industrial Applications: Acid proteases are widely used in the food industry. For example, they are used in cheese - making. Rennet, which contains acid protease, is used to coagulate milk proteins (casein) during cheese production. This process helps in the formation of curds and whey and is essential for the texture and flavor development of different types of cheese. In the brewing industry, acid proteases can be used to hydrolyze proteins in malt, which can improve the clarity and stability of beer and enhance the release of free amino acids that contribute to the flavor and fermentation process.

4. Optimal Conditions for Activity

As the name implies, acid proteases have an optimal pH in the acidic range. The exact optimal pH varies depending on the specific enzyme, but it generally falls between pH 2 and 5. The activity of these enzymes decreases significantly as the pH rises above this range due to changes in the ionization state of the active site residues. Temperature also affects the activity of acid protease. Most acid proteases have an optimal temperature range that usually lies between 30 - 50°C. At higher temperatures, the enzyme may denature and lose its activity, while at lower temperatures, the reaction rate slows down.

5. Production and Source

Acid proteases can be produced by various organisms. In nature, they are produced by many microorganisms such as fungi and bacteria. Fungi like Aspergillus species are well - known producers of acid proteases. These microorganisms secrete the enzymes into the extracellular environment to hydrolyze proteins for their own nutrient uptake. Commercially, acid proteases are usually produced through fermentation processes using these microorganisms. The enzyme can be purified from the fermentation broth and then used in different applications. In addition to microbial sources, acid proteases are also present in the digestive glands of animals and are produced by specific cells and then secreted into the digestive tract.

Appearance

Solid powder

Quality Standard

Enterprise standard

Shipping Condition

Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition

Dry, dark and at 0~4 ℃ for short term (days to weeks) or -20 ℃ for long term (months to years).

Shelf Life

>2 years if stored properly

Sample package

Aluminium foil bag

Commercial package

Aluminium Tin, Fiber drum

Origin

China