Lecture 5 Notes - Chemistry of Life
Lecture 5 Notes - Chemistry of Life BIL 255
Popular in Cellular & Molecular Biology
Popular in Biology
This 4 page Class Notes was uploaded by Elizabeth Mompoint on Tuesday September 22, 2015. The Class Notes belongs to BIL 255 at University of Miami taught by Dr. Mallery in Fall 2015. Since its upload, it has received 29 views. For similar materials see Cellular & Molecular Biology in Biology at University of Miami.
Reviews for Lecture 5 Notes - Chemistry of Life
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 09/22/15
Cell and Molecular Biology Lecture 5 The Molecules of Living Systems Cells derive their energy and main constituents through their ability to manipulate the chemical bonds of certain types of molecules Rearrangement of chemical bonds can release energy that can be used to drive cell processes or synthesize molecules essential for cell function Covalent bonds result from the equal nonpolar or unequal polar sharing of pairs of electrons to fill the outer electron shells of pairs of atoms Noncovalent bonds consist of the following interactions 0 Ionic bonds result from transfer of electrons from one atom to another leading atoms with positive charges and negative charges to attract each other 0 Hydrogen bonds weak electrostatic interactions with a single hydrogen atom shared between two electronegative atoms 0 Hydrophobic interactions occur between groups insoluble in water which tend to clump together minimizing exposure to H 20 0 Van der Waals dispersive interactions very weak interactions occurring between electrically neutral molecules that are very close together due primarily to slight perturbations of electron distributions between the atoms Water and the carbon atom have properties that are essential to life on Earth Only 30 of 92 elements commonly occur in living systems and 99 of living matter is made of C H O P S N Molecular composition of cells 0 Water H20 70 0 Inorganic ions asNa K Cl P04 1 0 Small monomers amino acids sugars nucleotides 5 O Macromolecules protein nucleic acids etc 24 MDNOSACCHALEI DES Mnnusaxcchartides usually have the general formula CHEIJJNI where n can be 3 4 5 or 5 and have two or more hyd rox39yli groups They either contain an aldehyde group 3 B and are called aldoses m a ketone gmuyp 2 0 and are called ketoses S carbnm TRIICISES S carlmn PENTDSESIv Ecarbun HEIIHZISESI Blomolecules are mostly carbon compounds amp are found 1n all a a a H O 11v1ng th1ngs k a Carbon IE quotEli aquot I 0 Eas1ly forms 4 strong covalent bonds mak1ng many small jz jZ jZ 2 Ens 5L5 glyceraldelwde ribose glucose 0 Allows 3D shapes that may evoke biological activity based upon conformation O Favors great chemical reactivity Sugars compounds with the formula of CH20n O Consist of monodi tri amp polysaccharides KETOSES wibu lose f Fructose Panel 233 Essential Celll Eiullbgy ill ed 5 Garland Science IBM lllite LIHIIIEE RING FORMATION In aqueous solution the aldehyde or lcamna grout all a sugar The hlli39m39a39 39l 5mm ml H143 ht mm In molecule tends to react wiih a hlydlronrl group all the same Many monosaccharides diflfer oniy in the spatial arrangement aldehyde Eur EthanIquot can rapaialllfrdhanpg EdmundIi molecule drierabvcloaing the molecule inta a ring Ho f atomsgthat isgmthay are isomers For example glucose aaaltlan ta then lhernThesaetwn zanaltlana are called H39 490 l quotgglactose and manncse have the same formula Itallimos but a and I quotFHng differ in the arrangement oi groups around one or two carbon HjE DH 1 O E F v aCIdS make HDH H new HjEDH the fats HIE 0H r Ci lle i m I I l 1 11p1ds We 7 39 I Wlth IE re er e filming the H Ja OH deem H COH he and a manager Ila linllaed ta angelihen the an ar H OH Ci lg li J IE team la Eireinn H common property Iucose mannose Note that each carbon atom hag a I Iumber 939 0f in wat f These small differences make only minor changes illquot the chemical properties of the sugars But they are recognized by 0 Form tr1acylglycerols phOSphOllpldS of membranes and ster01ds saw1195am Omarpmteins andthle reiomaquot haveimp am biological effects and cholesterol Nucleotides nitrogen containing quotringquot compounds made of a nitrogenousbase linked to a 5carbon sugar amp an inorganic phosphate P04 Amino acids molecules consisting of a basic amino group NH 2 an acidic carboxyl group COOH and a variable organic R group or side chain that is unique to each amino acid l quotr ah cHa Eglt ga rc3939 39 J 39 39 4L EH13 nu 3 a V gmqus art one end and lung hydrocarbon tails all theather n D Cholesterol clean 1be non CHI 5H2 H r r A J H mm duble bond 57 V camsEH E3312 I l is rigid and creates HO 1 quot 39 gquot le le 1 a kink in the chain H my 39 CHz CH H2 TIl39Iemsmfthe chain 39 id cl 4 H is free to rotate 2 2 I 39 I I in H II 23 th c39c gt 39 Testosterone 39 l 39 quot ll ng H2 CH tH ll 39 ll 4H g H spatefllllnug model carbon skelemn I I I unsnrumrm SATURATED Sl39mamm39 EH7 EH n 3 plant till EH n lillz H H EH2 EH II Eelrcgen lihl CiH II EH CH IIz Li Eggmi H cHs C1 all 1 H6 7 Bile acid Steroid l1 nilmum u stearl olelu fdeoxvchc ic mid igggtggtgmng Vitamin D acid acid Cawnm lmmw w mJSma Inc M I ah la denimd lCIa lCIBI Banal 3 In lunminlidl inlnnv drillIi Hil adnnd rimw Nil139 7 Phospholipide are the mailer constituents r I r V Glycerol Fatty oleell membranes V H l39l IIOIEty 0 acid tall Ph o srhale Q a i3quot 1 I lZIHz EIH Clllz hvtlrcnh chic quot39H lalw acid rails space lling model at T lil 397 I l T l I I quot 4 the nhaepholipidl pnaspharidylchaiine f 39I3 ll3 l3 ff if II ff H in Sugar in phospholipida two ol the a Hl groups in H H H H H H H H H C Iggy WI MS I Aquot m 6 glycerol are linked to fatty acids while the third D 39li i DI39IS I39IC Fl TEQSWE u W w y 39 9 general structure at OIH group I5 Indeed in phoap horlc acid The p C 7 3 WOSFMW39E39 phosphate is further linked to one of a variew gaping 39999 Jam Melquot and Sungquot 39quotD39 Aquot 9quot quotamm W mm mm of small polar groups lalceholel BASES 0 Nle NH Hi HH adenineth ii 2 U l uracil HC A P c HC C The bases are nitrogencuntalnlng ring g E X CH Hc SEN 0 compounds eltlher pyrimidines or purines H N OH OH C H cvmsine HlIlJOSE c l l H3 C c NH 6 NH Ill 6 lll 39i39 l 7 C xquot guanine l y A I l Nlll thymine H PR0 PYR IMIDINE PURIlME 2 Hibase OH H Farrel Isa Essential Cell laminar an ad le Garland Science Email Adenosine 5quotsmonophospl la te 239D meb0e dldeoxy 0 0 Ammo Ac1ds 1n Prote1ns Proteins make up 15 of a cell s dry mass 20 common amino acids which are all Otamino acids An alpha carbon is asymmetric allowing formation of 2 optical isomers L amp D but only the L stereoisomer of amino acids occur in biological proteins 1st amino acid discovered was asparagine 1806 in asparagus Last amino acid described was threonine 1938 Amino acids have a carboxyl group COOH amp amino group NH2 bound to an asymmetric carbon Zwitterion an ampholyte molecule carries charges on different groups as an amino acid but is neutral amphoteric can react as either an acid or base Isoelectric Point pH where no net charge in molecule Classes of amino acids classified by chemistry of RGroups 335339 33 ACIDIC negatively charged ASP amp GLU Egg r R group with 2nd COOH that ionizes above pH f p ncarhbn m side ellrain lHi nnninnizeci iorm ionized farm BASIC positively charged LYS ARG HIS in R group with 2nd amide that protonates below pH 70 if C l ais est issuers POLAR UNCHARGED SER THR ASN The atcarbon atom is asymmetric allowing for two G LN TYR mirrorimage or stereo isomers L and D are soluble In water ie hydrophilic NONPOLAR aliphatic ALA VAL ILE LEU PHE TRP r l U contain only hydrocarbons R groups it 1 hydrophobicity A AROMATIC amp SPECIAL TRP PH E TYR GLY Proteins contain exclusively Lamino acids PRO PantIndEssentialEallliiuimvmhamicmaliamiseunRNNl 1 J contain R groups with ring structures amp others Peptide bonds formed by a condensation reaction between the amino group of one amino acid amp the carboxyl group of another amino acid 0 Consist of dipeptide tripeptide pentapeptide oligopeptide polypeptide 0 Protein polymer of aLamino acids joined by peptide bonds PEPTIDE BONDS in proteins amino acids are commonly oined together Iby an amide linkage tallied a peptide lbond H a my no a a H D H D i y x I a ill I yquot The four atoms in each peptide bond red boxl form a rigid plainar unit There is no rotation aruund the 2 H lbonvd N C C N C C x l 7 I N ti c H I c sugar H R 5 r H OH H R H H 0quot SH Proteins are long pollymlers amino te miinus m I camlboxyil termin us or of amino acids linked by quotE39lm lms 39139 39 Cl 2 lil I39ll Ceteirmmus I peptide bonds and they HEN C C N C N C COO39 amino are always written with the L A g CIH iii terminus toward the left 2 CH 3 CH 3 Peptides a re shorter usua l I Rm fewer than 50 amino acids long The sequence of this tripeptide is hiistidline cysteine valline These two single bundls alllow relation 54 that long chains of amino acids are very exible Panel 25 Emmial Cell Bidqu Gull ed 3933 Garland Scienw 10H nucleotide In uu lumhhsJamnimhmlnl MIGNDM EFlS H0 39 1 DH HU 0H1 lMunmcchmida polysacclharide I m HH EEC OH l l l protein nucl eic acidi 3 nm u 5 HO P D V H a w I 3 HO leentida FULVME HS UH 0 47 0 o no 9H1 4 mm H Ellll DH a V H quotHF ntmmmn Itn h39f da smileIs H I H H H H O H N E39 CFDH Iil39lllllll H lell T f E C1 H E D 0H k I I I quotI 5 Hen Pnlwgptida cmsmom 8 mewus U a I E z a I m i A v A M l HO T Dv 5 0 P o 539 D o 55 390quot Ski 0 39 an O B Nuaaic acid