Exam1_L4_Carbs_Lipids Flashcards
(41 cards)
Enantiomers-
Mirror images- same chemical characteristics (sweetness)
NATURE ONLY D SUGARS
NATURE ONLY L (AMINO ACIDS)
UDP-glucose C4 epimerase
galactose can be made from glucose using this epimerase. (glucose/galactose are c4 epimers)
Mutarotation
spontaneous, no-enzyme, reversible action where straight sugars form rings.
99% of mono sugars exist in ring structure
(good b/c aldehyde/ketones are usually very reactive)
6 membered ring- 5 membered ring
Pyranose 6 membered ring
Furanose 5 membered ring
Alpha and Beta anomers. How do you find anomeric carbon?
Count from last non-ring carbon Alpha Anomer- (OH groups on same side )(restricted) Beta anomer (OH opposite sides) (less hindered)
Glycation
NON ENZYMATIC- reaction of ALDEHYDE or KETONE group in a sugar with AMINO group in proteins and makes a SCHIFF BASE –> oxidized to “AGES”
(advanced glycation end products)
Effects of Protein glycation?
- Decreased function
- Damages collagen in BV walls
- form AGE’s (advanced glycation end products)
Why is Chronic Hyperglycemia a concern?
CHglyC-> AGE’s> Major contributor to diabetic pathology.
- nephropathy
- Peripheral vascular/cardiovascular complications
How do you measure glycation of Hb? Why?
HbA1C test-
-Tests how adequate diabetic patient is regulating blood sugar
What is Glycosylation?
Adding Polysaccharide (>20) or Oligosaccharide (3-12 component sugars) to proteins, lipids, or other organic molecules in an ENZYMATIC REGULATED manner
-Process of making glycolipids and glycoproteins
Is it oxidation or reduction-
Acid to aldehyde? Alcohol to acid? Alcohol to aldehyde?
Acid to alcohol?, aldehyde to alcohol?, aldehyde to acid?
ALCOHOL ALDEHYDE ACID OX>
RED
Where is glucuronic acid from? Where is Iduronic acid form? What charge at physiological pH
Glucuronic acid is oxidized form of glucose
Iduronic acid is oxidized form of Galactose
Why is oxidation of sugars important physiologically?
Glucuronate is charged and added to hydrophobic molecules in the liver so that they can be more soluble and excretable from the body.
What are Amino and N-acetylated amino SUGARS?
Amino (N containing) Sugars reacts with lipids, proteins, or sugars OH group to make Glycosaminoglycans GAG’s , Glycolipids, or GlycoProteins
REDUCED SUGARS
C2 Epimers
C4 Epimers
Sugar ALCOHOLS
- Galactitol > galactose> Iduronic acid
- Sorbitol > Glucose > Glucuronic acid
- Mannitol > Mannose > multiple compounds
C2 epimers (Glucose Mannose) C4 epimers (Glucose Galactose)
GAG’s
LINEAR
POLYMERS of repeating DISACCHARIDES (50-150 repeats)
NEGATIVE CHARGE Attracts Water
Glycosides
Enzymatic reaction when a sugar molecule is COVALENTLY bound to the functional group of another molecule (not sugar) and is O or N linked
Glycosidases
Enzymes specific for glycosidic bonds; ie: alpha glucose configurations can be broken down by humans alpha glycosidases but we aren’t able to break down the Beta configuration of glucose (CELLULOSE) with it’s b1,4 glycosidic bonds.
18:3delta9,12,15
18 carbon lipid w/ 3 double bonds at carbons 9,12,15. Starting with carbon 1 at COOH end.
Name a lipid with 12 carbons and double bonds at 4,3,2.
12:3delta4,3,2
Omega system naming
start from carbon opposite COOH as carbon 1. name OMEGA then number of carbons until you get to first double bond.
What are the two essential fatty acids? Why?
Y-linoleic (w-6), and a-linolenic acids (w-3). Because we can’t make FA’s with double bonds past the carbon 9 position.
What is the precursor for arachidonic acid C20:4? what is arachidonic acid a major precursor for?
Linoleic w-6.
Arachidonic acid is MAJOR for EICOSANOID SYNTHESIS
What precursor for FA’s needed in growth and development?
Linolenic w3 for w3 FA’s
