Lactase: Difference between revisions

Latest revision as of 02:50, 11 December 2024

Enzyme involved in the digestion of lactose

Lactase

  [[File:|200px|alt=]]

Crystal structure of lactase

Lactase is an enzyme that is essential for the complete digestion of whole milk; it breaks down lactose, a sugar which gives milk its sweetness. Lactase is produced by many organisms, including humans, and is located in the brush border of the small intestine. The enzyme is crucial for the digestion of lactose in the diet, and its deficiency can lead to lactose intolerance.

Function[edit]

Lactase is responsible for the hydrolysis of lactose into its constituent sugars, glucose and galactose. This reaction is necessary for the absorption of these sugars into the bloodstream. The enzyme works by cleaving the β-glycosidic bond in lactose, a disaccharide, to yield the two monosaccharides.

Lactase Production[edit]

Lactase is produced by the enterocytes lining the small intestine. The production of lactase is highest in infants, who rely on milk as their primary source of nutrition. As humans age, the production of lactase typically decreases, which can lead to lactose intolerance in adulthood.

Lactose Intolerance[edit]

Lactose intolerance is a common condition caused by a deficiency of lactase. Individuals with lactose intolerance experience symptoms such as bloating, diarrhea, and abdominal pain after consuming lactose-containing foods. This condition is more prevalent in certain populations, particularly those of East Asian, West African, Arab, Jewish, Greek, and Italian descent.

Therapeutic Use[edit]

Lactase supplements are available for individuals with lactose intolerance. These supplements can be taken orally to aid in the digestion of lactose-containing foods. Additionally, lactase is used in the dairy industry to produce lactose-free products by pre-digesting the lactose in milk.

Also see[edit]

@@ Line 1: / Line 1: @@
-= Lactase =
+{{Short description|Enzyme involved in the digestion of lactose}}
+{{Infobox enzyme
+| name = Lactase
+| image = 1jyn.jpg
+| caption = Crystal structure of lactase
+| EC_number = 3.2.1.108
+| CAS_number = 9031-11-2
+| IUBMB_EC_number = 3/2/1/108
+| GO_code = 0000016
+}}
-'''Lactase''' is an enzyme crucial for the digestive system of humans and many other mammals. It is responsible for breaking down lactose, the sugar found in milk, into glucose and galactose, which can then be absorbed into the bloodstream. Lactase allows individuals to digest dairy products efficiently, playing a vital role in nutrition from infancy through adulthood.
+'''Lactase''' is an enzyme that is essential for the complete digestion of whole milk; it breaks down [[lactose]], a sugar which gives milk its sweetness. Lactase is produced by many organisms, including humans, and is located in the brush border of the small intestine. The enzyme is crucial for the digestion of lactose in the diet, and its deficiency can lead to [[lactose intolerance]].
-<youtube>
+==Function==
-title='''{{PAGENAME}}'''
+Lactase is responsible for the hydrolysis of lactose into its constituent sugars, [[glucose]] and [[galactose]]. This reaction is necessary for the absorption of these sugars into the bloodstream. The enzyme works by cleaving the β-glycosidic bond in lactose, a disaccharide, to yield the two monosaccharides.
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-&rel=1
-embed_source_url=http://www.youtube.com/v/_i2cclGYPx0
-&rel=1
-wrap = yes
-width=750
-height=600
-</youtube>
-== Function and Location ==
+[[File:LactaseMechanism2.png|thumb|Mechanism of lactase action on lactose]]
-Lactase is predominantly found in the small intestine's lining, where it is produced by the enterocytes. Its primary function is to hydrolyze lactose, facilitating the digestion of dairy products.
-[[File:Lactase mechanism.png|thumb|650px|Diagram showing lactase breaking down lactose into glucose and galactose.]]
+==Lactase Production==
+Lactase is produced by the [[enterocytes]] lining the small intestine. The production of lactase is highest in infants, who rely on milk as their primary source of nutrition. As humans age, the production of lactase typically decreases, which can lead to lactose intolerance in adulthood.
-== Biological Importance ==
+[[File:Lactase Processing.png|thumb|Processing of lactase in the small intestine]]
-Lactase is essential for mammals, particularly in early life stages, allowing for the digestion of mother's milk. In many humans, lactase production decreases significantly after weaning, leading to lactose intolerance in adulthood. However, a mutation that results in continued lactase production into adulthood has become prevalent in populations with a long history of dairy consumption.
-== Genetic Aspects ==
+==Lactose Intolerance==
-The persistence of lactase production into adulthood, known as lactase persistence, is governed by genetic variations near the lactase gene, LCT, on chromosome 2. These genetic differences are a classic example of human adaptation to dietary changes.
+Lactose intolerance is a common condition caused by a deficiency of lactase. Individuals with lactose intolerance experience symptoms such as bloating, diarrhea, and abdominal pain after consuming lactose-containing foods. This condition is more prevalent in certain populations, particularly those of East Asian, West African, Arab, Jewish, Greek, and Italian descent.
-[[File:1jyn.jpg|thumb|500px|Illustration of genetic variation associated with lactase persistence.]]
+==Therapeutic Use==
+Lactase supplements are available for individuals with lactose intolerance. These supplements can be taken orally to aid in the digestion of lactose-containing foods. Additionally, lactase is used in the dairy industry to produce lactose-free products by pre-digesting the lactose in milk.
-== Lactose Intolerance ==
+==Also see==
-Lactose intolerance results from the body's reduced ability to produce lactase, leading to symptoms such as bloating, diarrhea, and gas upon the consumption of dairy products. Managing lactose intolerance typically involves dietary adjustments or the use of lactase supplements.
+* [[Lactose intolerance]]
+* [[Enzyme]]
+* [[Disaccharide]]
+* [[Glucose]]
+* [[Galactose]]
-== Lactase Supplements ==
+{{Enzymes}}
-For individuals with lactose intolerance, lactase supplements are available to help digest lactose. These supplements are taken orally, often just before consuming dairy products, to aid in lactose digestion.
+{{Digestive system}}
-[[File:Lactase Processing.png|thumb|550px|Lactase supplements.]]
-== Role in Dairy Product Processing ==
-Lactase is also used industrially in the processing of dairy products, such as in the production of lactose-free milk and dairy products, making them suitable for lactose-intolerant individuals.
-== Research and Developments ==
-Ongoing research focuses on understanding the genetic basis of lactase persistence and developing improved treatments and dietary strategies for lactose intolerance.
-== External Links ==
-* [https://www.ncbi.nlm.nih.gov/gene/3938 NCBI Gene - LCT (lactase)]
-* [https://ghr.nlm.nih.gov/condition/lactose-intolerance Genetics Home Reference - Lactose Intolerance]
-== References ==
-<references/>
-* ''Genetics and Evolution of Lactase Persistence'' by Johnson and Wright
-* ''Lactose Intolerance and Health'' by the National Institutes of Health (NIH)
 [[Category:Enzymes]]
-[[Category:Human genetics]]
 [[Category:Digestive system]]
-[[Category:Dietary supplements]]
+[[Category:Carbohydrate metabolism]]
-{{stub}}