DNA replication

HEMOGLOBIN &
MYOGLOBIN
Protein Function

HEMOGLOBIN:

WHEN THE FIRST SUBUNIT OXYGENATES OR DEOXYGENATES THE FOLLOWING
THREE SUBUNITS FOLLOW SUIT AND THE SHAPE OF THE HBG MOLECULE IS
CHANGED.

Oxygenated
• R state (relaxed)
• When O2 is present, it binds to the iron attached to each heme and tugs on it which in turn flattens the heme to a planar shape
• The color of oxygenated blood is red (macroscopic)
• Carried from the heart throughout the body by the systemic arteries

Deoxygenated
• T state (tense)
• When no O2 is present the iron attached to each heme makes it into a dome shape
• The color of deoxygenated blood is blue (macroscopic)
• Carried from the body back to the heart by the systemic veins to be re
– oxygenated in the lungs

BOHR EFFECT
• O2 in lungs bound to hemoglobin
• Hgb travels through the body picking up CO2 from the cells and lowers the pH level
• Lower pH levels allow the Hgb to release O2 more easily to the organs
• When the pH is lower Hgb releases the needed amount of O2 throughout the body instead of targeting one areas so the whole body gets oxygen it needs to sustain organ life and excrete toxins
• If pH is to high the Hgb cannot distribute the O2 effectively to the body
• The Bohr effect gives the Hgb the strength it needs to travel through the whole body

MOLECULAR LEVEL BETWEEN NORMAL
HGB AND SICKLE CELL HGB

(OPHARDT, 2003)

CELLULAR LEVEL OF NORMAL HGB
AND SICKLE CELL HGB

(KELSO, 2013)

OXYGEN CARRYING CAPACITY
• Normal Red Blood Cells:

• Sickled Red Blood Cells:

• Can bind to O2

• Can bind to O2

• Round concave shape

• Crescent shape

• Travels through the body easily and releases O2 to organs and capillaries • Unable to have the capacity to carry O2 throughout the body because of its shape

• Lifespan of 120 days

• Block the blood flow to organs and capillaries because the stick together in the blood vessels

• Lifespan of 10-20 days

SICKLE CELL INHERITANCE
• Has beta subunit of valine where a glutamic acid should be in the amino acid chain
• Formed when a HBB mutation forms a abnormal beta-globulin called Hgb S
• 50% chance of having the sickle cell trait (being a carrier, but not have the disease) by inheriting one normal gene from one parent and one sickled gene from the other parent if both parents have trait
• 25% chance of inheriting a sickle gene from each parent and having the disease if both parents have trait
• 25% chance of inheriting a normal gene from each parent and not have the disease or the sickle cell trait if both parents have trait but not the disease
• 50% chance of having trait an 50% chance of having normal genes if one parent has trait and the other does not.
• 100% chance of inheritance of sickle cell disease if both parents have the disease

SICKLE CELL ANEMIA

(BLOOD.CO.UK, 2012)

CITATIONS
• Ophardt, C. (2003) Retrieved September 25, 2013 from www.Elmhurst.edu
• Kelso, T. (2013) Understanding Sickle Cell Trait and Precautions for Training
Athletes. Retrieved September 26, 2013 from http://breakingmuscle.com
• Casiday, R. and Frey, R. (2008) Hemoglobin and the Heme Group. Mental
Complexes in the Blood for Oxygen Transport. Retrieved September 12, 1013 from http://www.chemistry.wustl.edu
• Wolfe, G (2000) Thinkwell Biochemistry. Retrieved September 13, 2013 from wgu.thinkwell.com • Sickle Cell and Blood Donation. (2012) Retrieved September 26, 2013 from http://www.blood.co.uk

Citations: • Ophardt, C. (2003) Retrieved September 25, 2013 from www.Elmhurst.edu • Kelso, T. (2013) Understanding Sickle Cell Trait and Precautions for Training Athletes. Retrieved September 26, 2013 from http://breakingmuscle.com • Casiday, R. and Frey, R. (2008) Hemoglobin and the Heme Group. Mental Complexes in the Blood for Oxygen Transport. Retrieved September 12, 1013 from http://www.chemistry.wustl.edu • Wolfe, G (2000) Thinkwell Biochemistry. Retrieved September 13, 2013 from wgu.thinkwell.com • Sickle Cell and Blood Donation. (2012) Retrieved September 26, 2013 from http://www.blood.co.uk