Here we did this web quest, linked to us on schoology.
“COLLAGEN STRUCTURE AND FUNCTION
Proteins are the most diverse class of biological molecules. Most of your body is made up of proteins. Each protein consists of one or more polypeptide chains, in which amino acids are strung together in a specific order. This amino acid sequence or ‘primary structure’ is the key to the shape and function of the protein. Interactions among different amino acids along the length of the polypeptide chain cause it to coil, bend, and fold into a complex shape. Some proteins consist of two or more polypeptide chains. In many cases, the polypeptide chains form a rounded or globular shape. Most enzymes are like this, as is the oxygen-carrying hemoglobin molecule. In other cases, polypeptide chains form long strands or sheets. These fibrous proteins are often structural components, such as keratin and collagen.
Activity
In this activity, you will explore the structure and function of collagen, the most abundant protein in the human body. You will begin by visiting a Protein Data Bank site, where the structure of collagen is described and illustrated in a “Molecule of the Month” feature. Next, you will research the effects of osteogenesis imperfecta (OI), a genetic disorder that affects the structure or number of collagen molecules.
Part 1.
Use your browser to go to http://www.rcsb.org. This site is a Protein Data Bank where you can search for any information about your favorite proteins, including everyone’s favorite, collagen.
Do a search at the very top of the page for collagen or click on this Molecule of the Month: Collagen link to view the article on collagen.
Read the information and view the graphics. Use this information to answer the following questions:
- Describe the primary structure of collagen. What are the major amino acid components in collagen?
Collagen makes a tight triple helix amino acid. Or, the repetition of three amino acids to make the sturdy structure. The three major amino acid components are glycine, proline, and hydroproline- a modified proline
- What role does vitamin C play in collagen formation? What happens when a person does not get enough vitamin C in his or her diet?
Vitamin C helps in the creation of hydroxyproline, which modifies the normal proline amino acids after the creation of collagen chains. A lack of vitamin C slows the production of hydroxyproline which causes scurvy. Symptoms of scurvy are loss of teeth and easy bruising.
- Describe the quaternary structure of collagen (the way in which the polypeptide chains are arranged).
Every third amino acid is a glycine. The rest of the amino acids are proline and hydroxyproline which fill the empty spaces. It is a very uniform structure.
Part 2.
Use your browser to go to the Web site of the Osteogenesis Imperfecta Foundation at
On the left side of the home page, click the link “About OI”, then find the “Facts About OI” section.
Read the material in the sections entitled “Facts on Osteogenesis Imperfecta” and “Types of OI.” Use what you have learned to answer the following questions:
- What is the main symptom of osteogenesis imperfecta? What are some other symptoms that people with OI may have? The main symptom of osteogenesis imperfecta is a fragile skeleton. Other symptoms people with OI might have are bone deformity, low bone density, and skin hyperlaxity (or easy bruising).
- Type I osteogenesis imperfecta causes fewer problems than the other forms. How does the collagen structure in Type I OI differ from that of the other types? The collagen in type 1 OI is less than the amount of collagen in any of the other types. It has closer collagen levels than that of those without OI.
Read the handout (pdf) in the resources section on Bone Structure.
- Describe the role of collagen in bones. Why do collagen problems lead to bone problems? Collagen in bones helps keep the bones strong and healthy. It keeps them from doing things like breaking and fracturing. A lack of collagen leads to fragile bones, broken bones, or bone diseases.”
Doing this helped me learn more about the purpose of collagen.
Alex Blair's Biology Blog :) 