carbohydrates Flashcards
functions of carbohydrates
energy source
storage
structural
interellular communication
ring structures of larger monoshaccaries
pyranoses -6
furanoses - 5
smaller monosaccharides
aldoses
ketoses
why are ring structures formed on the larger monosaccashrides
oxygen on the anomeric carbon
what can carbohydrates form
D and L isomers
D in life
what conformation do carbohydrates form
chair confomration
2 anomie’s due to OH orientation on anomeritc carbon
bond between monomers
glycosidic
either alpha or beta depending on anomer
substitute sugars
carbohydrate with other groups
e.g. protein, lipid, acetyl
glycosaminoglycnas
lots of charge leading to repulsion
component of ECM
types of polysaccarides
homopolysaccarides
heteropolysaccarides
linear or branched
cellulose
glucose beta glycosidic bonds
straight chains due to B
H bonding between polymer chains
chitin
contains amine group increasing charge therefore stronger bonds
exoskeletons and cell wall of fungi/algae
starch
food reserve in plants
insoluble granules in cytoplasm
starch forms
a-amylose linear homopolysaccaride glucose via alpha helical formation (kinked) amylopecitn glucose monomers alpha 1-4/1-6 linakgaes branching
glycogen
similar to amylopectin but more compact and branched
glycogen synthesis
glucose binds to UDP
glycogenin creates glucose primer using UDP glucose molecules
allows binding to aa on glycogenin
glycogen synthase sticks another UDP glucose on
repeat to make chain
branching enzyme moves glucose molecules to another glycosidic bonding, branching
glycogen degreatation
glycogen phosphorylase removes glucose at ends
debranching enzyme acts as transferase, removes glucose near branch point
glycoproteins/oligosaccharies
carbohydrate chains linked to protein
often branched and found on cell surface (signalling)
how can carbohydrate groups be linked
N/O glycans
N linked glycosylation
spread through whole protein, effects on protein folding activity
O linked glycosaltion
occurs in clusters on specific proteins with protective role
salivary mucin
O links
2-7 sugars attachede
glycolipdis
act as self signals/regognition factors , intercellular commincation
feature of bacterial cell wall - different to human lipopolysaccharide
glyco RNA
sugar attached to RNA
digestion of carbohydrtaes
A malaise breaks 1-4 links in starch
polysaccharides to oligosaccarhres
pancreatic applause and other glycosides digest
what happens to sugars that cannot be digested
fermented in the colon
carbohydrates and oral health
glycolipids can be used as a food source for bacteia
bacteria can attach to structures by using glycoprotiens
glycocalyx
glycoprotien and glycolipid
protective barrier between cell and outside
bacteria can produce this to stick to and form plaque
