Post on 18-Dec-2015
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BIOMOLEKUL(Dr. I Dewa Ayu Susilawati, drg. M. Kes)Setelah mempelajari bab ini, anda diharapkan mampu:Menjelaskan jenis, struktur, sifat & fungsi biomolekul yang menyusun tubuh manusiaMenjelaskan 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 materiTerdiri 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 MANUSIAUnsur 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)
SIMBOLUNSURNOMER ATOMPERSEN BERAT OCHNCaPKSNaClMgOksigenKarbonHidrogenNitrogenKalsiumFosforKaliumSulfurNatriumKlorinMagnesium86172015191611171265,018,59,53.31,51,00,40,30,20,20,1
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 (+ atau -)* Contoh: C-O; C-N; O-H; N-H
van der Waals forces: dipole-dipole interactions
Ikatan HidrogenIkatan hidrogen pada molekul Air
Makromolekul= polimer*Polimer karena tersusun oleh banyak atom, maka BM nya besar > 100.000 dalton makromolekul*Empat kelompok biomolekul utama: masing-masing mempunyai monomer karakteristik
MonomerPolimerAsam lemakDiasilgliserol, triasilgliserolMonosakaridapolisakaridaAsam aminoPolipeptida, proteinnukleotidaPolinukleotida (RNA, DNA)
PROTEIN
FUNCTION ANDSTRUCTURE
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
Protein proteos the firstPlay crucial roles in virtually all biological processes
Proteins are organic compounds made of amino acids (polymers of -amino acids)
Kinds of amino acids: 20
Amount of amino acids > 50
AMINO ACIDSAmino 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).
Amino acidssymbol
One-letter symbolThree-letter symbolAmino acidAAlaalanineBAsxaspartic acid or asparagineCCyscysteineDAspaspartic acidEGluglutamic acidFPhephenylalanineGGlyglycineHHishistidineIIleisoleucineKLyslysineLLeuleucineMMetmethionineNAsnasparaginePProprolineQGlnglutamineRArgarginineSSerserineTThrthreonineU*SecselenocysteineVValvalineWTrptryptophanX**Xaaunknown or 'other' amino acidYTyrtyrosineZGlxglutamic acid or glutamine
Ser-Thr : dipeptideAsp-Glu-Phe: threepeptidePhe-Gly-His-Thr : tetrapeptide< 10 aa : olygopeptide< 50 aa : polypeptide> 50 aa : protein
Essential amino acids :human body cannot synthesize themfrom other compounds,so they must be obtained from food
EssentialNonessentialIsoleucineAlanineLeucineAsparagineLysineAspartic AcidMethionineCysteine*PhenylalanineGlutamic AcidThreonineGlutamine*TryptophanGlycine*ValineProline*Serine*Tyrosine*Arginine*Histidine
Protein Structure Hierarchy
N terminalC 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
L I P I DSTRUCTURE ANDFUNCTION
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 DPenyebab tidak larut dlm air karena rantai hidrokarbon alifatik panjang atau cincin 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 > 4Asam KarboksilatAsam Lemak : fatty acids
Asam Lemak Jenuh (saturated): tak ada ikatan rangkapAsam lemak tak jenuh (unsaturated): ada ikatan rangkap
Trigliserid (Triasilgliserol): TGStruktur dasar TG :1 gliserol + 3 asam lemakTG : lipid utama untuk sumber energi
TG : ester dari gliserol dg 3 asam lemak
fosfolipidFosfolipid 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 groupsNUKLEOTIDA
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, dllDinucleotideFAD, NADPolynucleotideDNA, RNA
Monosaccharide classifications based on the number of carbons
Number of CarbonsCategory NameExamples4TetroseErythrose, Threose5PentoseArabinose, Ribose, Ribulose, Xylose, Xylulose, Lyxose6HexoseAllose, Altrose, Fructose, Galactose, Glucose, Gulose, Idose, Mannose, Sorbose, Talose, Tagatose7HeptoseSedoheptulose, Mannoheptulose
Disaccharide descriptions and components
Sugar Alcohols, Amino Sugars, and Uronic AcidsGlucitol or Sorbitol(a sugar alcohol) Glucuronic acid (a uronic acid) Glucosamine(an amino sugar)
Polysaccharides are polymers of simple sugarsMany 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 unitsGlycogenGlucose 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 -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.
Contoh soal
Sebutkan bahan organik dan anorganik yang menyusun gigi.Gigi yang utuh memiliki struktur yang keras, sedangkan yang mengalami karies lebih lunak. JelaskanMeskipun komposisi kimia gigi dan tulang sama, tetapi kekerasannya berbeda, jelaskanJaringan ikat bersifat kenyal dan ulet,, jelaskan struktur dan sifat protein penyusun jaringan ikat.Saliva selalu diproduksi sehingga komponen-komponennya setiap saat selalu diendapkan pada gigi, jelaskan pengendapan molekul-molekul saliva ke gigiJelaskan molekul-molekul penyusun antibodi, hemoglobin, interleukin, reseptor
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