Transcript What are the functions of biomolecules

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Rules
Group leader
Laptop
Color pens, tapes,
papers, big size
post it notes
Recording
Notes taking
Questioning
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Survey
Consultation
Thinking Map
SG notes
TeLi Time
References
1.
2.
3.
4.
Get one sketch book (at least 14 sheets)
Before class, prepare your Thinking Map
You may add during class discussion
Credits will be given
Top 5
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5
I am STUCK !!!
GOT it!!
1. Appoint a TeLi person during every class
session (class leader)
2. Present new terms for the day
3. Briefly define the terms
Assessment
Laboratory reports
5-6
10%
1
10%
2-3
20%
Test 1
1
10%
Test 2
1
10%
Final examination
-
40%
100%
Mini project
Presentations/Assignments/Project
Total
1. Form into 4 in a
group.
2. A group will be
selected to present
lab work of the day
3. Report may be
submitted via these
modes (will be
announced later)
1. End class
presentation
2. Blog / websites
3. Journal format
1. Form into 4-5
members in a group
2. Task will be posted
in MyGuru2/Class
3. Presentations may
be in form of…
1. Life
presentation
2. Video
presentation
3. Blog/Websites
4. LeT Kits
5. Performing Arts
6. Mapping
What is Biochemistry ?
1 minute discussion with your pair
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A scientific discipline to explain life at the molecular level
uses the tools and terminology of chemistry to describe the various
feature of living things
offer insights into the treatment of diseases e.g. cancer, diabetes
etc.
Offer answers to :
e.g.
what are we made of?
how do we work?
why we react in a certain way?
1. Biomolecule
2. Water chemistry
3. Protein : Structure & metabolism
4. Enzyme : Properties & Kinetics
5. Carbohydrate : structure & metabolism
6. Lipid : Classes & Metabolism
7. Aerobic metabolism
At the end of this topic, you should be able to :
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Name the common functional groups
Name the linkages in biological molecules
Draw the general molecular structure of biomolecules
Explain the process of oxidation and reduction
What do you know….
the process of oxidation and reduction
1 minute discussion with your pair
Biomolecules
• Biomolecules are compound of carbon and hydrogen (CH)
• Four major classes of biomolecules & building blocks:
1.
2.
3.
4.
Carbohydrate  sugars
Protein  amino acids
Lipids  fatty acids
Nucleic acids  nucleotides
What are the functions of biomolecules:
1. Synthesize larger molecules
2. Carry out special biological functions e.g ATP
3. Take part in complex reaction pathways
http://www.bbc.co.uk/education/asguru/biology/02biologicalmolecules/02c
arbohydrates/15monosaccharides/index.shtml
• Chemical
properties of
molecule are
depend on by
specific
arrangement of
atoms
= functional
groups
• Most
biomolecules
contain more than
1 fn gp.
e.g. sugar
molecules
Several
hydroxyl gp
Aldehyde gp
Sugar and carbohydrates
• Contain alcohol groups & aldehydes/ketones
• Simple/monomer : monosaccharide
 glucose, fructose, ribose, galactose
• Polymer: polysaccharide
 starch & cellulose; glycogen
• Complex :
 nucleotide : contain ribose / deoxyribose
 glycoprotein : protein contain carbohydrate
 glycolipid : lipid contain carbohydrate.
or
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or
D-glucose
an aldose
an aldohexose
D-fructose
a ketose
a ketohexose
Monosaccharides are connected by GLYCOSIDIC BOND
via the process of dehydration
C1
C4
Glycosidic
bond
Amino acids, peptides and protein
•
A.a. contains :
1. amino group
2. carboxylic
acid group
3. side chain
gp/R group
Amino acids are linked together by
peptide bonds
Polypeptides : peptides ( up to 50 a.a)
protein (longer)
Fatty acids and lipids
• Contain :
1. one carboxylic acid
2. with long HC chain
•Are monocarboxylic acids
• Usually contain even number of C atoms
• water insoluble
• E storage
O
Alkyl gp
Contains
C & H atoms
RCH2
C
OH
Carboxyl
gp
• Monounsaturated f.a. = contain one double bond
• Polyunsaturated f.a. = contain two or more double bond
• Saturated f.a = only single bond (saturated with hydrogens!)
• one carboxylic acid with even C number & no branching
Fatty acids are combined with one glycerol to form a fat
molecule  triglycerol // triacylglycerol //TAG
Through a process :esterification/dehydration/condensation
Nucleotides and nucleic acids
Contain :
1. 5C sugar
2. A nitrogenous base
3. Phosphate gp.
Base consist of purine or pyrimidine.
e.g. ATP
e.g. DNA/ RNA
Complementary base pairing
DNA : A-T ; C-G
RNA: A-U ; C-G;
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Assembling small molecules into polymeric
macromolecules needs energy
Breaking polymeric molecules into smaller
molecule produces energy
BIOCHEMICAL PROCESSES
All life processes consist of chemical reaction catalyzed by enzymes
What are the primary functions of metabolism?
1. To acquire and use energy
2. To synthesize molecules needed for cellular structure & function
3. For growth & development
4. To remove waste & other toxins
Biochemical reactions involve enzyme catalysis
Most common reaction types:
1. Nucleophilic substitution
2. Elimination
3. Addition
4. Isomerization
5. Oxidation-reduction / redox reaction
Nucleophilic substitution
Def: one atom or gp substituted for another
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Nucleophilic Substitution-acyl
O
O
R C CH2C SCoA + CoA-SH
O
O
R C SCoA + CH3C SCoA
Sulfur nucleophile attacks C=O
Addition:
 two molecules combine to give one.
 One molecule usually multiple bonded.
O
C O
HC
HO
C H + H2O
C O
hydration
O
Addition occurs at C=C
O
C O
CH
CH2
C O
O
Elimination
 - a molecule loses atoms usually in the form of a small molecule like
water.
O
C O
2H C OPO3
CH2 OH
PGA

O
C O
2C OPO3
CH2 +H O
2
PEP
Water is lost to form phosphoenolpyruvate
Isomerization:
 molecule rearranges atoms
O
O
C O
C O
2H C OPO3
H C OH
2CH2 OH
CH2 OPO3
3-phosphoglycerate to 2-phosphoglycerate
Hydrolysis:
 water cleaves (splits) a covalent bond and inserts itself.
O
CH2 O C R
O
H C O C R + 3 H2O
O
CH2 O C R
Hydrolysis of a fat
CH2 OH
H C OH
CH2 OH
O
+ 3 HO C R
Oxidation-reduction
Open up your text book: find out what is oxidation and reduction.
In biochemistry redox reactions are usually recognized by the following
changes:
• Oxidation occurs when a molecule loses two hydrogens and/or gains an
oxygen. (-2H & +O
@ -2H @ +O)
• Reduction occurs when a molecule gains two hydrogens and/or loses
an oxygen. ( +2H & -O @ +2H @ -O)
Oxidation
O
C O
H C OH
CH3 NAD+
lactate
O
C O
C O
CH3
NADH + H+ puruvate
• Lactate is oxidized.
• NAD+ is oxidizing agent.
Reduction
CH3C -OH
II
O
CH3CH2 -OH
Acetic acid
Ethyl alcohol
•Reduction occur as a molecule loses
oxygen and /or gain hydrogen
End of lecture
Please check the learning outcomes