BC 3 Carbohydrate & Lipid Flashcards
Carbohydrate
Aldoses or ketoses
aldose sugars suffix ose
ketose sugars suffix ulose (except fructose)
Monosaccharides: linear three or more carbons, one carbonyl o
(CH2O)n 3ctrioses, 4c tetroses
Stereoisomers, epimers, enantiomers
stereo, same formula, differ in position of OH
Epimers: differ from only ONE specific carbon (left or right)
enantiomers: mirror image, D and L sugars, almost ALL D form
Mutarotation
Formation of Ring Structures, Cyclization
-non enzymatic process
alpha (OH below) and beta (OH below) anomers anomeric carbon (c1)- counting down from non ring carbon
Beta anomers 63%, interconvert via linear form
linear less that 1% monosaccharides-chemically active aldehyde or ketone used for glycation
glycation
addition of single glucose (linear) to protein via non enz reaction in a non specific manner. blood plasma in interstitium
increased glycation-> decreased function
hyperglycemia leads to damage
glycosylation
addition of polysaccharides or oligosaccharides
lipids or protiens, enzyme regulated
glycolipids/glycoproteins. cotranslational and posttranslational mod’s in ER & Golgi
Oxidized and Reduced Sugars
sugars can be oxidized in aldyhyde form to form an acid-oxidized sugar
ose to onic acid or onate
uronic or urinate if terminal hydroxyl group
glucaronic acid from glucose, and iduronic acid from galactose. Negatively charged.
Clincal relevance?
reduced sugars
sugar alcohols
if aldehyde is reduced, all of the carbon atoms contain alcohol. andy sufar is a polyol. sorbitol from glucose, or galactitol from galactose
alcohol – aldehyde – acid
left reduction, right oxidation
amino and N-acylated amino sugars
amino group substitutes for one hydroxyl (NH2) ie glucosamine
can be acetylated, acetylglucosamine
essential sugars for glycosaminoglycans, glycolipids and glycoproteins.
Glycosaminoglycans
linear polymers of repeating disaccharides that form ground substance of extracellular matrix. negatively charged. Neg for water adsorption (cushion)
Glycosides
???
sugar bound to another functional group via glycosidic bonds
O glycosidic or N glycosidic
each can be alpha or beta configuration
human glycosidases can break down (alpha amylase) only the alpha form. That’s why we cant break down cellulose, but yes starch.
disaccharides, oligosaccharides, polysaccharides
need more detailed info here
disaccharides
Sucrose
-glucose and fructose (two anomeric carbons linked, not a reducing sugar, free OH still attached to ring)
Lactose
-glucose and galactose (leaves one anomeric carbon, reducing sugar)
Maltose
glucose and glucose
polysaccharides glycogen (animal) starch (plant) cellulose (plant)
starch: glucose monomers linked in two forms
- linear (amylose)
- branched (amylopectin
Glycogen: more densely branched, one gram adsorbs 3 grams of water
cellulose, glucose with B1-4 polymers,
Lipids
Fatty acids, non membrane and membrane lipids
fatty acids
long chain carboxylic acids
number of carbons atoms, followed by a colon, number of double bonds and the position. 18:1(9)
carboxyl carbon is number 1
omega numbering system is opposite (kind of) just number of carbons away from methyl group end.
gamma linoleic acid. and alpha linolenic acid
we ingest them bc humans cant make double bonds past C9 position. Important for growth an development
Branched chain fatty acids: methyl groups. Deficiency of alpha hydroxylase to cleave methyl groups leaves accumulation nerve tissue plasma damage
Trans FA: hydrogenation of veggie oils. double bond. Trans fatty acids and heart disease.
tri acyl glycerols TAGS
storage form of fatty acids. Three FA to glycerol backbone, hydrophobic and non polar
steroids and cholesterol esters
steroids have tetracyclic rings derived from cholesterol
polar group of cholesterol is esterified to a fatty acid it becomes a cholesterol ester. non polar. top of cholesterol gets long hydrocarbon chain
