Glycobiology Flashcards
week 2 lect 1
3 functions of glycoproteins:
blood clotting, reproduction and immune system recognition
functions of carbohydrates:
energy sources, energy storage, structural component of cell membranes (bacterial cell walls), nucleotide biosynthesis (ribose + deoxyribose), lipid biosynthesis (acetyl coA)
monosaccharide formula:
Cn(H2O)n
same number of oxygens as there are carbons
aldose?
this is a type of monosaccharide -which has an aldehyde group on an end carbon
ketose?
has a ketone group on one of the middle group
when can monosaccharides become cyclic?
when there are more than five carbons
pyranose?
6-membered ring
5 carbon and one oxygen
furanose?
5-membered ring
4 carbon and one oxygen
what isomer is glucose of galactose?
stereoisomer
what isomer is fructose of glucose/galactose?
structural - different structural arrangement
lactose intolerant?
mutation in the lactase gene
homopolysaccharides?
contain only a single type of monosaccharide
heteropolysaccharides?
contain two or more different kinds of monosaccharide
Glycogen is branched - what are the glycosidic bonds that cause this branching?
a 1,4 glycosidic bonds
a 1,6 glycosidic bonds
what enzyme hydrolyses a1,4 glycosidic bonds in glycogen?
glycogen phosphorylase
what enzyme hydrolyses a1,6 glycosidic bonds in glycogen?
debranching enzyme
where is excess glucose stored as in plants?
roots and seeds
During fermentation, what three volatile fatty acids do we start with?
acetate, butyrate, propionate
N-acetyl-D-glucosamine?
chitin
where is chitin found?
in the exoskeletons of inverterbrates
what is the process that results in glucose being formed from pyruvate?
gluconeogenesis
proteoglycans?
carbohydrates modified with a carbohydrate component
endotoxin AKA?
lipo-polysaccharide
where can glycoproteins be found?
extracellular matrix, outer face of the plasma membrane and in the blood
eCG
equine chorionic gonadotropin
EPO
erythropoietin
what does the basic proteoglycan unit consist of?
a core protein with covalently attached glycosaminoglycans
give an example of a glycosaminoglycans?
heparin
what is heparin?
an anticoagulant
what sort of disorders might require treatment from heparin?
cardiac/aortic/arterial thrombosis
pulmonary thrombosis and thromboembolism
disseminated intravascualr coagulation
what is aggrecan?
a proteoglycan, it is a major component of cartilage
describe the difference between the alpha and beta ring structures:
a - newly formed OH group on the opposite sides from the CH2OH (below the ring)
b - newly formed OH group on same sides as the CH2OH (above the ring)
what is the anomeric carbon within the Haworth projection of a cyclic monosaccharide?
the one that has a centre of chirality and is bonded to the ‘deciding’ OH group
