Chapter 11 BIOCHEM

monosaccharides

simplest saccharides composed of three carbons

What is the name?

Dihydroxyacetone (a ketose)

What is the name?

D-Glyceraldehyde (an aldose) (C3H6O3)

What is the name?

L-Glyceraldehyde (an aldose) (C3H6O3)

isomers

have the same molecular formula but different compounds

constitutional isomers

differ in the order of attachment of atoms

enantiomers

superimposable mirror images

stereoisomers

atoms are connected in the same order but differ in spatial arrangement

disasteroisomers

isomers that are not mirror images

epimers

differ at one of several symmetric carbon atoms

anomers

isomers that differ at a new asymmetric carbon atoms formed on ring closure

What is this compound?

glyceraldehyde (C3H6O3)

What is this compound?

D-Altrose (C6H12O6)

What is this compound?

D-Glucose (C6H12O6)

What is this compound?

D-Mannose (C6H12O6)

What is this compound?

a-D-Glucose (C6H12O6)

What is this compound?

B-D Glucose (C6H12O6)

What is this compound?

D-Ribose

What is this compound?

D-Deoxyribose

What is this compound?

D-Fructose

What is this compound?

D-Galactose

What is happening in this diagram?

aldehyde & alcohol forms hemiacetal

What is happening in this diagram?

ketone & alcohol forms hemiketal

the chemical basis for ring formation is the reaction of ______ or _____

aldehyde & alcohol form hemiacetal or ketone & alcohol form hemiketal

what is glucose’s resulting intramolecular hemiacetal consist of?

six carbon ring pyranose

whats is ketose’s fructose intramolecular hemiketal named?

furanose b/c it looks like furan

how is pyranose formed ?

with the D-Glucose (open chain form)

what is this compound?

a-D Glucopyranose

what is this compound?

B-D glucopyranose

how is furanose made?

D-Fructose

what is this compund?

a-D-Fructofuranose

α-form

hydroxyl at C-1 is below the plane of the ring

β-form

hydroxyk at C-1 is above the plane of the ring

furanose form of fructose

α and β form refers to orientation of the hydroxyl at C-2

pyranose form

fructose forms this and a furanose form seen in fructose derivatives

what compound is this?

α- D Fructofuranose

what compound is this?

β-D Fructofuranose

what compound is this?

α- D Fructopyranose

what compound is this?

β-D Fructopyranose

What compound is this?

β-D-Ribose

What compound is this?

β-2-Deoxy-D-ribose

what compound is this?

α-D Glucose

what compound is this?

α-D Fructose

what compound is this?

α-D Galactose

what compound is this?

α-D Mannose

what are the two different types of conformation of pyranose rings?

boat & chair

in pyranose chair form the carbon substituent rings have 2 orientations

axial & equatorial

β-D-Glucopyranose

chair conformation b/c axial positions have H reducing steric hindrance

What form and what name is this compound?

chair form of B-D-Glucose

what form and name of this compound?

boat form of B-D-Glucose

furanose rings

like pyranose not planar and usually on the envelope form

ribose component of biomolecules which conformations are observed the most?

C-2 is out of the plane on the same side as C-5 (C-2 endo) or C-3 is out of the plane on the same side as C-5 (C-3-endo)

what envelope conformation and compound is this?

C-3-endo β-D-Ribose

what envelope conformation and compound is this?

C-2-endo B-D-Ribose

a solution of glucose contains

1/3 a anomer 2/3 B anomer 1% open chain

two anomeric forms of glucse are in ….

equilibrium and the free open-chain form reacts with oxidizing agents

suagrs that react with oxidizing agents are called

reducing sugars

sugars that react without oxidizing agents are called

nonreducing sugars

Open-chain glucose can react with Cu+ reducing the copper while itself becoming

oxidized

glucose is a reducing sugar, therefore can react with amino acids like

Lys or Arg residues in proteins

what is an example of glucose reacting with an amino acid?

glucose and hemoglobin forming glycosylated hemoglobin A1c

what allows one to monitor the long term-control of blood glucose levels in diabetics?

the amount of hemoglobin A1c in the blood

Reactions between ___ & ____ often impair protein function

carbohydrates & proteins

advanced glycation end products (AGES) have…

been implicated in a number of pathological conditions

monosaccharides are joined to _____ & ___ through _____ bonds

alcohols & amines glycosidic

what is formed from an O-glycosidic bond

anomeric carbon atom & oxygen atom

what is formed through an N-glycosidic bond?

anomeric carbon & amine

what compound is this?

B-L frucose

what compound is this?

GalNAc

what compound is this?

GlcNAc

what compound is this?

Sialic acid (Sia)

phosphorylation

modification of carbohydrates

makes the sugars anionic and prevents from leaving the cell

facilitates the metaolism of sugars

oligosaccharides

two or more monosaccharides are linked by O-glycosidic bonds

what is sucrose cleaved by?

invertase

where is sucorse obtained from?

sugar cane

what is the linkage for glucose and fructose?

a for glucose b for fructose

lactose

consists of galactose linked to a glucose by a β-1,4 linkage

maltose

degradation of large oligosaccharides made up of 2 glucose molecules linked by a 1,4 linkage

hydrolyzed by maltase

what is this compound name?

sucrose

what is this compound name?

lactose

what is this compound name?

Maltose

polysaccharide glycogen

glucose storage in animals

glucose units in glycogen are linked by

a-1,4-glycosidic bonds w/ branches formed by α-1.6 glycosidic bonds for every 12 glucose units

in plants glucose is stored as

starch: amylose and amylopectin

amylose

linear polymer of glucose units linked by a 1,4 glycosidic bonds

cellulose

homopolymer of glucose units by a B-1,4-glycosidic bond

The β linkage yields a straight chain capable of interacting with other cellulose molecules via

H-bonds to form strong fibrils

the a linkages of starch and glycogen form

compact hollow cylinders suitable for accessible storage

insoluble and soluble fiber are an ___ ___ ____

important part of the diet

mammals cannot digest _____ and ____ the rate at which digestion products pass through the large ____

cellulose & increasing, intestine

soluble fibers such as _______ ____ also aid in digestion

polygalacturonic acid (pectin)

human milk oligosaccharides protect ___ ____ ___

newborns from infection

more than 150 different _____ have been identified in human milk

oligosaccharides

these carbohydrates are ___ ____ by the infant but they ___

not digested; play an important protective role against bacterial infection

milk oligosaccharides

prevent streptococcus bacteria from VJJ cause pneumonia blood poisoning or meningitis

carbohydrates can be linked to form

glycoproteins

glycoproteins

mainly protein by weight

proteoglycans

attached to a polysaccharide called a glycosaminoglycan; mainly carbohydrate by weight

mucins or mucoproteins

attached to the carbohydrate by N-acetylgalactosamine; act as lubricants

carbohydrates can be linked to proteins through _______ or ___ or ____

asparagine (N-linked) or serine or threonine (o-linked)