Proteins

Proteins are chains of amino acids.

Proteins are important nutrients for humans.

Proteins have particular structures that depend on their amino acid sequence.

Proteins are encoded in genes in our chromosomes. The genetic code is how living cells to translate nucleic acid sequence information into protein sequence.

Proteins serve as structural elements in our cells and as enzymes. Some enzymes are now known to be RNA.

Some proteins moonlight: they have two very different functions/activities.

Proteins that are mutated may cause diseases including anemia, cystic fibrosis and cancer.

Some proteins have been mutated deliberately through genetic engineering methods to be more stable or to be produced by other organisms.

Classroom work with proteins

Protein Assays

• A rapid assay for total protein in a mixture (like milk): The Fralin/Horn Teaching manual for the Bradford Protein Assay( .pdf file)(Bio-Rad microassay conditions/nutrition, truth in labeling, math, powers of ten). The Manufacturer's Bio-Rad Protein Assay Instruction Manual (GOTO page 7 of the .pdf file, which is page 5 in the manual for the mfr's instructions for the microassay--Section 2.3)
• A lesson about protein structure, with Internet links to free, professional software for visualizing molecular structures (modeling, computational biology)
• Experiment with enzymes: Study yeast catalase to examine the effects of substrate concentration, pH, temperature, etc.(biochemistry, enzyme assay, investigation)

Links for Protein Assays (comparisons)

• Biuret: Pierce, Sigma
• Bradford: Bio-Rad, Pierce, Sigma
• Lowry: Pierce, Sigma

Protein Structure

Links for Protein Structures

Protein Activity

• Links for Enzyme Assays (html/.pdf)
• Immunoassay--ELISA (.pdf)

Protein Electrophoresis (.pdf)