Amylase: Difference between revisions

Line 16:

==Function==

In the human body, α-amylase is part of digestion with the breakdown of carbohydrates in the diet.The mechanism involved includes catalyzing substrate hydrolysis by a double replacement mechanism, forming a covalent glycosyl-enzyme intermediate and hydrolyzed through oxocarbenium ion-like transition states. One of the carboxylic acids in the active site acts as the catalytic nucleophile during the formation of the intermediate. A second carboxylic acid operates as the acid/base catalyst supporting the stabilization of the transition states during the hydrolysis.

In the human body, α-amylase is part of digestion with the breakdown of carbohydrates in the diet.The mechanism involved includes catalyzing substrate hydrolysis by a double replacement mechanism, forming a covalent glycosyl-enzyme intermediate and hydrolyzed through oxocarbenium ion-like transition states. One of the carboxylic acids in the active site acts as the catalytic nucleophile during the formation of the intermediate. A second carboxylic acid operates as the acid/base catalyst supporting the stabilization of the transition states during the hydrolysis.<ref>DOI: 10.1021/bi701652t</ref>

Salivary α-Amylase hydrolyzes the (α1-4) glycosidic linkages of starch, separating it into short polysaccharide fragments. Once the enzyme reaches the stomach, it becomes inactivated due to the acidic pH. Further breakdown of starch occurs by secretion of a second form of the enzyme by the pancreas. Pancreatic juice enters the duodenum and pancreatic α-amylase further cleaves starch to yield maltose, maltotriose and oligosaccharides. The oligosaccharides are referred to as dextrins, which are fragments of amylopectin consisting of (α1-6)branch points. Microvilli of the intestinal epithelia break maltose and dextrins into glucose, which gets absorbed into the circulatory system. Glycogen has a relatively similar structure as starch, and thus proceeds in the same digestive pathway.

Navigation menu

Page actions

Page actions

Personal tools

Navigation

Search

Tools

@@ Line 16: / Line 16: @@
 ==Function==
-In the human body, α-amylase is part of digestion with the breakdown of carbohydrates in the diet.The mechanism involved includes catalyzing substrate hydrolysis by a double replacement mechanism, forming a covalent glycosyl-enzyme intermediate and hydrolyzed through oxocarbenium ion-like transition states. One of the carboxylic acids in the active site acts as the catalytic nucleophile during the formation of the intermediate. A second carboxylic acid operates as the acid/base catalyst supporting the stabilization of the transition states during the hydrolysis.
+In the human body, α-amylase is part of digestion with the breakdown of carbohydrates in the diet.The mechanism involved includes catalyzing substrate hydrolysis by a double replacement mechanism, forming a covalent glycosyl-enzyme intermediate and hydrolyzed through oxocarbenium ion-like transition states. One of the carboxylic acids in the active site acts as the catalytic nucleophile during the formation of the intermediate. A second carboxylic acid operates as the acid/base catalyst supporting the stabilization of the transition states during the hydrolysis.<ref>DOI: 10.1021/bi701652t</ref>
 Salivary α-Amylase hydrolyzes the (α1-4) glycosidic linkages of starch, separating it into short polysaccharide fragments. Once the enzyme reaches the stomach, it becomes inactivated due to the acidic pH. Further breakdown of starch occurs by secretion of a second form of the enzyme by the pancreas. Pancreatic juice enters the duodenum and pancreatic α-amylase further cleaves starch to yield maltose, maltotriose and oligosaccharides. The oligosaccharides are referred to as dextrins, which are fragments of amylopectin consisting of (α1-6)branch points. Microvilli of the intestinal epithelia break maltose and dextrins into glucose, which gets absorbed into the circulatory system. Glycogen has a relatively similar structure as starch, and thus proceeds in the same digestive pathway.