Download - BIOMOLEKUL & IKATAN KIMIA
BIOMOLEKUL(Dr. I Dewa Ayu Susilawati, drg. M. Kes)
Setelah mempelajari bab ini, anda diharapkan mampu:
1.Menjelaskan jenis, struktur, sifat & fungsi biomolekul yang menusun tubuh manusia
2.Menjelaskan jenis & sifat ikatan kimia pada biomolekul
BIOMOLEKUL(Molekul Kehidupan)
Kehidupan: hasil kumulatif dari interaksi senyawa-senyawa kimia yg menyusun sel-sel suatu organisme hidup
Organisme hidup bila diuraikan, terdiri dari senyawa-senyawa kimia = biomolekul
Biomolekul = senyawa penyusun kehidupan
AtomMolekul terdiri dari atom/unsur* Atom: unit terkecil materi
Terdiri dari:inti: neutron (tidak bermuatan) &
proton (bermuatan positif)kulit : orbit elektron (bermuatan
negatif)* Unsur: substansi mengandung satu jenis atom
STRUKTUR ATOM
UNSUR-UNSUR YANG MENYUSUN TUBUH MANUSIA
SIMBOL UNSUR NOMER ATOM PERSEN BERAT
OCHNCaPKSNaClMg
OksigenKarbonHidrogenNitrogenKalsiumFosforKaliumSulfurNatriumKlorinMagnesium
8617
20151916111712
65,018,59,53.31,51,00,40,30,20,20,1
Unsur –unsur kelumit (kurang dari 0,01%): Boron (B), Kromium (Cr), Kobalt (Co), Tembaga (Kuprum, Cu), Fluorin (F), Iodin (I), Besi (Fe), Mangaan (Mg), Molibdenum (Mo), Selenium (Se), Silikon (Si), Timah (Sn), Vanadium (V) dan Seng (Zn)
Reaksi antar atom Ikatan Kimia
* Adalah tarik menarik antara atom atau molekul yg memungkinkannya membentuk senyawa kimia.* Tarik menarik disebabkan oleh:
- Kekuatan elektromagnetik- Muatan berlawanan- Neklei-elektron- Kutub-kutub (dipole-dipole)
* Kekuatan ikatan- Ikatan kuat: ikatan kovalen,
ikatan ion- Ikatan Lemah : interaksi dipole,
ikatan hidrogen, ikatan Van Der Waals
Ikatan ion
Ikatan kovalenAtom membentuk molekul dg cara berbagi elektron
Ikatan kovalen non polar* Atom-atom yg membentuk ikatan kovalen berbagi elektron secara merata karena memiliki keelektronegatifan sama atau hampir sama* Keelektronegatifan: kemampuan inti atom untuk menarik elektronnya* Misal ikatan C-C; C-H; H-H
Ikatan kovalen polar* Jika salah satu atom lebih elektronegatif, elektron tidak terbagi secara merata, tetapi lbh tertarik ke salah satu inti atom kutub-kutub (δ+ atau δ-)* Contoh: C-O; C-N; O-H; N-H
van der Waals forces: dipole-dipole interactions
Ikatan Hidrogen
Ikatan hidrogen pada molekul Air
Makromolekul= polimer* Polimer karena tersusun oleh banyak atom, maka
BM nya besar > 100.000 dalton makromolekul* The four major classes of biomolecules each have
their own characteristic monomers and corresponding polymers
Monomer Polimer
Asam lemak Diasilgliserol, triasilgliserol
Monosakarida polisakarida
Asam amino Polipeptida, protein
nukleotida Polinukleotida (RNA, DNA)
PROTEIN
STRUCTURE AND
FUNCTION
• Protein proteos the firstPlay crucial roles in virtually all biological processes
• Proteins are organic compounds made of amino acids (polymers of α-amino acids)
• Kinds of amino acids: 20
• Amount of amino acids > 50
AMINO ACIDS
• Amino acids are molecules containing an amine group, a carboxylic acid group and one of the twenty R-groups.
• The amino acids in a polymer chain are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues
Peptide bondA peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, thereby releasing a molecule of water (H2O).
One-lettersymbol
Three-lettersymbol
Amino acid
A Ala alanine
B Asx aspartic acid or asparagine
C Cys cysteine
D Asp aspartic acid
E Glu glutamic acid
F Phe phenylalanine
G Gly glycine
H His histidine
I Ile isoleucine
K Lys lysine
L Leu leucine
M Met methionine
N Asn asparagine
P Pro proline
Q Gln glutamine
R Arg arginine
S Ser serine
T Thr threonine
U* Sec selenocysteine
V Val valine
W Trp tryptophan
X** Xaa unknown or 'other' amino acid
Y Tyr tyrosine
Z Glxglutamic acid or glutamine (or substances such as4-carboxyglutamic acid and 5-oxoproline thatyield glutamic acid on acid hydrolysis of peptides)
Amino acidssymbol
• Ser-Thr : dipeptide• Asp-Glu-Phe : threepeptide• Phe-Gly-His-Thr : tetrapeptide• < 10 aa : olygopeptide• < 50 aa : polypeptide• > 50 aa : protein
Essential Nonessential
Isoleucine Alanine
Leucine Asparagine
Lysine Aspartic Acid
Methionine Cysteine*
Phenylalanine Glutamic Acid
Threonine Glutamine*
Tryptophan Glycine*
Valine Proline*
Serine*
Tyrosine*
Arginine*
Histidine
Essential amino acids :human body cannot synthesize themfrom other compounds,so they must be obtained from food
Protein Structure Hierarchy
N terminal
C terminal
Tertiary structure
A hemoglobin molecule consists of four polypeptide chains Each of the globins is folded
into a secondary and tertiary structure. Then, all four are put together
into the hemoglobin molecule's quaternary structure
Quaternary structure
Protein function in humans (dynamic & structural function)
1. Enzymatic catalysis2. Transport & storage e.g. transferrin, ferritin, hemoglobin, etc3. Coordination motion, contractile e.g. actin, myosin, etc4. Mechanical support, structural proteins e.g. collagen, elastin, etc5. Immune response e.g. immunoglobulin, interferon, complements, cytokines, etc6. Hormones e.g. insulin, somatotropin, thyrotropin, etc7. Receptors8. Control gen transcription & regulation e.g histone, NFkB, robosomal protein, etc
L I P I D
STRUCTURE AND
FUNCTION
Adalah kelompok senyawa organik berlemak atau berminyak yang tidak larut dalam air, dapat diekstrak dari sel atau jaringan dengan pelarut non polar seperti kloroform atau eter.
L I P I D
Penyebab tidak larut dlm air karena rantai hidrokarbon alifatik panjang atau cicin benzena yang bersifat non polar.
Jenis lipid utama manusia: asam lemak, trigliserid (triasil gliserol), fosfolipid, kolesterol, kolesterol ester
• Lipids are a broad group of naturally occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The main biological functions of lipids include energy storage, as structural components of cell membranes, and as important signaling
Macam-macam lipid
* Penyusun utama lipid: asam lemak* Asam lemak: asam karboksilat C > 4
Asam Karboksilat Asam Lemak : fatty acids
Asam Lemak Jenuh (saturated): tak ada ikatan rangkap
Asam lemak tak jenuh (unsaturated): ada ikatan rangkap
Trigliserid (Triasilgliserol): TG
Struktur dasar TG :1 gliserol + 3 asam lemak
TG : lipid utama untuk sumber energi
TG : ester dari gliserol dg 3 asam lemak
fosfolipid
Fosfolipid tdr :- Gliserol- asam lemak- Senyawa fosfat
Phospholipid:phosphatidylcholin
Phospholipid:Phosphatidylinositol (PI)
Phospholipid:phosphatidylserin
Phospholipid cell membrane
Phospholipid pada lipoprotein plasma
KOLESTEROL
Kolesterol:- membran- vitamin D- hormon streroid
A nucleotide is composed of a nucleobase (nitrogenous base), a five-carbon sugar, and one to three phosphate groups
NUKLEOTIDA
NUCLEOTIDE * make up the structural units of RNA and DNA* play central roles in metabolism, they serve as
sources of chemical energy: adenosine triphosphate (ATP) and guanosine triphosphate (GTP),
* participate in cellular signaling: cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP),
* cofactors of enzymatic reactions: coenzyme A (CoA), flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), and nicotinamide adenine dinucleotide phosphate (NADP)
polinukleotida
• MononucletideATP, GTP, ADP, AMP, dll
• DinucleotideFAD, NAD
• PolynucleotideDNA, RNA
KARBOHIDRAT
- Carbohydrates consist (CH2O)n
-Carbohydrates include sugars, starches,
cellulose and many other compounds found in
living organisms.
-simple sugars or monosaccharides.
-combination of two simple sugars: disaccharide.
-Carbohydrates consisting of two to ten simple
sugars are called oligosaccharides,
- larger number are called polysaccharides.
Number ofCarbons Category Name Examples
4 Tetrose Erythrose, Threose
5 PentoseArabinose, Ribose, Ribulose, Xylose, Xylulose, Lyxose
6 Hexose
Allose, Altrose, Fructose, Galactose, Glucose, Gulose, Idose, Mannose, Sorbose, Talose, Tagatose
7 Heptose Sedoheptulose, Mannoheptulose
Monosaccharide classifications based on the number of carbons
Disaccharide descriptions and components
Sugar Alcohols, Amino Sugars, and Uronic Acids
Glucitol or Sorbitol (a sugar alcohol)
Glucuronic acid (a uronic acid)
Glucosamine (an amino sugar)
Polysaccharides are polymers of simple sugars
Many polysaccharides, unlike sugars, are insoluble in water. Dietary fiber includes polysaccharides
and oligosaccharides that are resistant to digestion and absorption in the human small intestine but which are completely or partially fermented by
microorganisms in the large intestine.
Amylose molecules consist typically of 200 to 20,000 glucose units which form a helix as a result of the bond angles between the glucose units
GlycogenGlucose is stored as glycogen in animal tissues by the process of glycogenesis. When glucose cannot be stored as glycogen or used immediately for energy, it is converted to fat. Glycogen is a polymer of α-D-Glucose. The glucose chains are organized globularly like branches of a tree originating from a pair of molecules of glycogenin, a protein with a molecular weight of 38,000 that acts as a primer at the core of the structure. Glycogen is easily converted back to glucose to provide energy.
homework
• 1. Bagaimanakan struktur Monoasilgliserol, diasilgliserol?
• 2. Bagaimanakah struktur ATP, ADP, AMP?• 3. Bagaimanakah struktur ester kolesterol