Glycated hemoglobin
From Proteopedia
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==Structure== | ==Structure== | ||
<StructureSection load='5HY8' size='340' side='right' caption='Glycated hemoglobin (PDB ID 5hy8)' scene=''> | <StructureSection load='5HY8' size='340' side='right' caption='Glycated hemoglobin (PDB ID 5hy8)' scene=''> | ||
| - | Hemoglobin is the protein that transports oxygen in our blood. In the <scene name='82/821067/Overall/1'>structure shown here</scene>, all four heme groups bind to oxygen. Two amino acid side chains are covalently bound to a sugar molecule (they are glycated), indicating that this protein experienced high sugar levels for a long time. The sugar is fructose, and it is bound via a glycosidic bond to the sidechain of lysine. | + | Hemoglobin is the protein that transports oxygen in our blood. In the <scene name='82/821067/Overall/1'>structure shown here</scene>, all four heme groups bind to oxygen. Two amino acid side chains are covalently bound to a sugar molecule (they are glycated), indicating that this protein experienced high sugar levels for a long time. The sugar is fructose, and it is bound via a glycosidic bond to the sidechain of lysine. In hemoglobin from patients with untreated diabetes, the modifications include glucose linked to the amino terminal groups of chain A and chain B as well as modification of lysine side chains by glucose. The HbA1c test specifically tests for the modification of the <scene name='82/821067/Ntermb/2'>amino terminus of the B chain</scene> (not modified in this structure). |
</StructureSection> | </StructureSection> | ||
Revision as of 13:39, 15 July 2019
Glycated Hemoglobin is a form of hemoglobin with sugars attached to certain amino acid side chains. When blood sugar levels in an individual are high for long periods of time (hyperglycemia) as is the case for [[diabetes}people with diabetes]]) when blood sugar is not managed, these sugar modifications accumulate. The so-called HbA1c test is used as a measure of hyperglycemia over the past 3 months. The time span of 3 months corresponds to the average time red blood cells remain in the blood stream. When they are replenished by fresh cells, these carry hemoglobin that does not yet have the modification [1].
Structure
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