Essential Idea:  Proteins have a very wide range of functions in living organisms.

• Outline answer to each objective statement for topic 2.4 (coming soon)
• Quizlet study set for this topic

At SHS, Topic 2.4 is taught in the following class unit(s):​​

• Protein Structure and Function (unit 31)
  

2.4.U1  Amino Acids are linked together by condensation to form polypeptides.

• Describe polypeptide chain formation in terms of the formation of peptide bonds and condensation reactions.
• Determine the number of peptide bonds given the number of amino acids in a polypeptide.
• Define dipeptide, oligopeptides and polypeptide.  

2.4.U2  There are 20 different amino acids in polypeptides synthesized on ribosomes.

• State the number of amino acids used by living organisms to make polypeptides.
• Given an image of an amino acid, classify the amino acid chemical properties based on R group properties. 
• Outline the role vitamin C plays in the conversion of proline to hydroxyproline.  ​

2.4.U3  Amino Acids can be linked together in any sequence giving a huge range of possible polypeptides.

• Calculate the possible number of amino acid sequences given n number of amino acids.

2.4.U4  The amino acid sequence of polypeptides is coded for by genes.

• Outline the relationship between genes and polypeptides.

2.4.U5  A protein may consist of a single polypeptide or more than one polypeptide linked together.

• Outline the structure and function of three example proteins composed of two or more polypeptides linked together.

2.4.U6  The amino acid sequence determines the three-dimensional conformation of a protein.

• Contrast the structure of globular proteins with the structure of fibrous proteins.
• Describe the structure of membrane bound globular proteins.

2.4.U7  Living organisms synthesize many different proteins with a wide range of functions.

• Contrast the generalized function of globular proteins with generalized function of fibrous proteins.
• List ten functions of proteins in a cell or organism.
• Describe the function of enzyme proteins.
• Describe the function of hormone proteins.
• Describe the function of immunoglobulin proteins.
• Describe the function of pigment proteins.
• Describe the function of structural proteins

2.4.U8  Every individual has a unique proteome.

• Define proteome.
• Contrast proteome with genome.

2.4.A1  Rubisco, insulin immunoglobulins, rhodopsin, collagen and spider silk as examples of the range of protein functions.

• State the function of each of the following proteins:  rubisco, insulin, immunoglobulin, rhodopsin. collagen, spider silk, actin, myosin, casein, hemoglobin, acetylcholine receptor, oxytocin, prolactin, ferritin, billirubin, fibrinogen, transferrin and albumin.

2.4.A2  Denaturation of proteins by heat or by deviation of pH from the optimum.

• Define denaturation.
• Outline the effect of heat and pH on protein structure.

2.4.S1   Drawing molecular diagrams to show the formation of a peptide bond.

• Draw peptide bond formation in a condensation reactions.

2.4.NOS  Looking for patterns, trends, and discrepancies- most but not all organisms assemble proteins from the same amino acids.

• Explain the trend of organisms assembly of polypeptides from the same amino acids.
• Describe a discrepancy of the trend of all organisms using the same amino acids to assemble polypeptides.

In the News:

• AI protein-folding algorithms solve structures faster than ever (2019-07-22)
• 5 challenges we could solve by designing new proteins (TED talk 2019)
• Molecular insights into spider silk (2018-12-07)
• Mysterious family of proteins are cellular pressure sensors (2018-11-15)
• Bigger proteins, stronger threads: Synthetic spider silk (2018-08-21)
• Unlocking Secrets of Sour Flavors With Something Found in Your Ears (2018-02-03)
• The function of many proteins remains uncertain: Blind spots on protein maps quantified (2017-12-04)
• ​What web browsers and proteins have in common (2017-09-19)
• New synthetic amino acid for emerging class of drugs (2014-08-31)
• Memory protein fades with age (2013-08-28)
• A single protein may help explain memory loss in old age (2013-08-29)
• China pours money into proteins (2014-06-10)
• Proteins and a pregnancy woe (2014-07-16)
• How spiders spin silk: Mechanism elegantly expla-ins how spider silk can form so quickly and smoothly (2014-08-05)
• How hummingbirds evolved to detect sweetness (2014-08-21)
• Water 'thermostat' could help engineer drought-resistant crops (2014-08-27)
• Unusually elastic protein found by researchers; may have originated in cnidarian elastomer (2015-01-23)
• The most complete catalog of proteins in king cobra venom yet (2016-08-15)
• Proteomics and precision medicine (2016-02-05)
• Spinning a new version of spider silk (2015-05-28)
• Researchers discover protein protecting against chlorine (2014-12-18)
• Chemists find a way to unboil egg whites: Ability to quickly restore molecular proteins could slash biotechnology costs (2015-01-26)
• How unboiled eggs could help fight food waste (2015-02-02)

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