Presentation 06 Biomolecules1

7/17/2019 Presentation 06 Biomolecules1

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1. CONDENSATION (DEHYDRATION)

Loss of H2O▪ - OH (hydroxyl group)▪ - H (hydrogen)Covalent bonds are formed

Energy is expendedPolymerase enzyme

2. HYDROLYSISAddition of H 2OCovalent bonds are brokenEnergy is releasedHydrolase enzyme

How many molecules of water are needed tocompletely hydrolyze a polymer that is 10monomers long?



Sugars and polymersof sugars

ClassesMonosaccharidesDisaccharides andoligosaccharidesPolysaccharides

ImportanceFuelBuilding materials



ImportanceMajor cell nutrientsIncorporated into more complexcarbohydrates

ClassificationLocation of carbonyl group (C=O)

AldoseKetose

Size of C-skeleton (3- 7 C’s) Arrangement around C’s

Linear formRing form (in aqueous solutions)▪ - H on top of plane of ring▪ -OH on top of plane of ring



IMPORTANCEMaltose (glucose + glucose)Lactose (glucose + galactose)Sucrose (glucose + fructose)

FORMATION AND STRUCTUREGlycosidic linkage – covalentbond between 2monosaccharidesCondensation or dehydrationsynthesis reactions

Draw the structure ofa) sucrose formed from a 1-2

glycosidic linkage of glucose and fructose

b) galactose formed from the 1-4 glycosidic linkage of glucose and galactose.

1-4 GLYCOSIDIC LINKAGE



IMPORTANCEStructural polysaccharides

Cellulose and chitinStorage polysaccharides

Starch and glycogen

STRUCTURE AND FORMATION• Hundreds to thousands of

monosaccharides joined byglycosidic linkages

•Homopolysaccharides• Starch ( 1,4 linkages)

• Amylose• Amylopectin

• Cellulose ( 1,4 linkages)• Heteropolysaccharides



large molecules assembledfrom smaller molecules bydehydration reactionshydrophobic and non-polarglycerol + fatty acid fatfatty acids have long C-skeletons (16-18 atoms)with a carboxyl endester linkages are formedwhen 3 fatty acids join toglycerol

FunctionsEnergy storageCushioning of vital organsInsulation



glycerol + 2 fattyacids andphosphate group

amphipathichydrophobic tailshydrophilic heads

assemble into

bilayersmajor componentsof cell membranes



C-skeleton with fourfused ringsVary in the functional

group attached to theringsCholesterol

Cell membranes

Used for synthesis ofsex hormones▪ Testosterone▪ Estrogen



Amino acids arranged in alinear chain and foldedinto a globular formAmino acidsStructure

Carboxyl (-COOH) endAmino (-NH2) endR (variable) group attachedto the -Carbon

ClassificationNonpolarPolarCharged (acidic/basic)



http://legacy.owensboro.kctcs.edu/gcaplan/anat/notes/amino_acid_structure_2.jpg





http://www.personal.psu.edu/staff/m/b/mbt102/bisci4online/chemistry/charges.gif





Sequence ofamino acids in apolypeptide chain

Change in oneamino acid maychange propertiesof entire chain

Glu Valsubstitution causessickle cell anemia

C ili /f ldi d H b d f i



Coiling/folding due to H-bond formationbetween carboxyl and amino groups of non-adjacent amino acids.R groups are NOT involved.



3d structure resulting fromfolding of the 2 structures stabilized by bondsformed between amino

acid R groupsforms many shapes (e.g.globular compact proteins,fibrous elongated proteins)disruption denaturation



Present in some proteins



Present in some proteinswhose tertiary structures(subunits) join to form aprotein complex



Structure affected bypHsalt concentrationpresence of solvents

temperatureChaperone proteins incell help in refoldingproteins



DNA (deoxyribonucleicacid)

Provides directions for ownreplicationDirects RNA synthesisControls protein synthesis

RNA (ribonucleic acid)mRNA directs proteinsynthesis in the ribosometRNA transfers a specificamino acid to apolypeptide chainrRNA combines with aprotein to make up aribosome



Nucleotide

Nucleoside

Nitrogenousbase

Pentosesugar

Phosphate



5’ end

3’ end

Presentation 06 Biomolecules1

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