All Proteins

Where is lingual lipase produced, and where does it function?

• Produced in the mouth

• Can function in the mouth and stomach

What is the function of lingual lipase?

It hydrolyzes triacylglycerol (TAG), releasing free fatty acids (FFAs) and producing diacylglycerol (DAG).

• TAG Digestion

Does lingual lipase break ester bonds?

Yes. It catalyzes hydrolysis of TAG ester bonds using water

Where does gastric lipase function?

In the stomach

What is the function of gastric lipase?

It hydrolyzes TAG ester bonds, releasing FFAs and producing partially hydrolyzed glycerides.

• TAG Digestion

Does gastric lipase break ester bonds?

Yes. It is a digestive enzyme that catalyzes ester-bond hydrolysis in TAG

Where does pancreatic lipase function?

In the small intestine, where it performs most enzymatic digestion of dietary TAG.

What is the function of pancreatic lipase?

It primarily hydrolyzes the ester bonds at the sn-1 and sn-3 positions of TAG, producing 2-MAG and two FFAs

• TAG Digestion

Does pancreatic lipase break ester bonds?

Yes. It catalyzes hydrolysis of TAG ester bonds using water

Where is procolipase found, and what is its function?

Procolipase is secreted by the pancreas into the small intestine

What is the function of procolipase?

Activated to colipase and helps pancreatic lipase

Where does trypsin function in lipid digestion?

In the small intestine,

Function of trypsin:

Trypsin cleaves procolipase to produce active colipase

Where does acyl-CoA synthetase function?

Inside enterocyte

What is the function of acyl-CoA synthetase in lipid absorption?

Synthesizes TAG in the enterocyte

• It activates fatty acids to fatty acyl-CoA, which can then be used in TAG reformation by other enzymes.

Where does B48 function?

On the chylomicron

• But it moves around a lot!

What are the three functions attributed to B-48?

• Stabilize the lipoprotein

• Identifies it as a carrier of dietary lipids

• Allows lipoprotein lipase to work

Where is lipoprotein lipase located?

On the luminal surface of muscle and adipose tissue

What is the function of lipoprotein lipase?

It hydrolyzes TAG carried in chylomicrons, releasing DAG and FFA that can be taken up by muscle or adipose tissue.

Does lipoprotein lipase break ester bonds?

Yes. It catalyzes the hydrolysis of TAG ester bonds

Where is albumin found?

Albumin is a protein in the blood

What is albumin’s function?

Transports fatty acids with less than or equal to 10 carbons to the liver

Which molecules are proteins but NOT ENZYMES?

• Procolipase/ colipase

• B48

• Albumin

Which molecules are proteins and enzymes?

• Lingual lipase

• Gastric lipase

• Pancreatic lipase

• Trypsin

• Acyl CoA synthetase

• Lipoprotein lipase

Which proteins can break ester bonds?

• Lingual lipase

• Gastric lipase

• Pancreatic lipase

• Lipoprotein lipase