Related Experiment Video

Updated: May 23, 2026

Isolation of Primary Mouse Hepatocytes for Nascent Protein Synthesis Analysis by Non-radioactive L-azidohomoalanine Labeling Method
08:04

Isolation of Primary Mouse Hepatocytes for Nascent Protein Synthesis Analysis by Non-radioactive L-azidohomoalanine Labeling Method

Published on: October 23, 2018

An appetite for protein

Stephen J Simpson1, David Raubenheimer1

  • 1Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia.

Science (New York, N.Y.)
|May 21, 2026
PubMed
Abstract

More Related Videos

Evaluation of Amino Acid Consumption in Cultured Bone Cells and Isolated Bone Shafts06:32

Evaluation of Amino Acid Consumption in Cultured Bone Cells and Isolated Bone Shafts

Published on: April 13, 2022

Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae07:24

Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae

Published on: June 11, 2020

Related Concept Videos

Overview of Protein Metabolism01:21

Overview of Protein Metabolism

Proteins are broken down into amino acids during digestion. Unlike fats and carbohydrates, which are stored for later use, proteins are not. Instead, amino acids are either used to produce ATP through oxidation or contribute to the creation of new proteins for the growth and repair of the body. Any surplus amino acids from the diet are converted into glucose or triglycerides rather than excreted.
Amino acids play various roles in the body once they are absorbed into cells. They are restructured...
Proteins: Dietary Sources and Requirements01:28

Proteins: Dietary Sources and Requirements

Consuming animal-based products offers high-quality proteins that contain optimal levels and combinations of essential amino acids, crucial for tissue repair and growth. Foods like eggs, milk, fish, and most meats are a source of complete proteins. Legumes and cereals are abundant in proteins; however, they typically lack a full range of essential amino acids. As a result, they are considered incomplete protein sources. Some plant sources like soybeans, quinoa, and amaranth do contain complete...
Protein Absorption01:12

Protein Absorption

Proteins in the gastrointestinal tract typically come from food, but they can also originate from disintegrated cells or secreted enzymes. In the stomach, the enzyme pepsin breaks down these proteins into polypeptides. The fragments then move into the duodenum as a semi-fluid mass called chyme. Pancreatic proteases, such as trypsin and chymotrypsin, and intestinal brush border enzymes like carboxypeptidases further dismantle the polypeptides into tripeptides, dipeptides, and free amino acids.
Protein Digestion01:02

Protein Digestion

Protein digestion begins in the stomach, where the highly acidic environment can easily disrupt protein structure by exposing the peptide bonds of polypeptide chains. After polypeptide chains are broken into individual amino acids by a series of digestive enzymes, the amino acids are transported to the liver via the bloodstream to produce energy.
What are Proteins?01:55

What are Proteins?

Overview
What are Proteins?01:28

What are Proteins?

Proteins are polymers of amino acids linked together by peptide bonds. Proteins and polypeptides are interchangeably used to refer to long chains of amino acids. However, polypeptides have a molecular weight of fewer than 10,000 daltons, while proteins have greater molecular weight.  Polypeptides with less than 20 amino acids are called oligopeptides or simply peptides. Interactions among the constituent amino acid side chains of proteins help them fold into a stable 3-dimensional structure...