Drug delivery & Tissue engineering Lab Chapter 1. An Overview of Biological Basics

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 The Chemical Nature of Polynucleotides Biochemists determined the components of nucleotides during the 1940s The component parts of DNA – Nitrogenous bases: Adenine (A) Cytosine (C) Guanine (G) Thymine (T) – Phosphoric acid – Deoxyribose sugar 2-3

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Nucleotides and Nucleosides RNA component parts – Nitrogenous bases Like DNA except Uracil (U) replaces Thymine – Phosphoric acid – Ribose sugar Bases use ordinary numbers Carbons in sugars are noted as primed numbers Nucleotides contain phosphoric acid (cf. nucleosides)

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Purines and Pyrimidines Adenine and guanine are related structurally to the parent molecule purine Cytosine, thymine and uracil resemble pyrimidine 2-5

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 DNA Linkage Nucleotides are nucleosides with a phosphate group attached through a phosphodiester bond Nucleotides may contain one, two, or even three phosphate groups linked in a chain 2-6

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Trinucleotide The example trinucleotide has polarity – Top of molecule has a free 5’-phosphate group = 5’ end – Bottom has a free 3’- hydroxyl group = 3’ end

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 DNA Structure The Double Helix Rosalind Franklin’s x-ray data suggested that DNA had a helical shape The data also indicated a regular, repeating structure DNA was believed to require an irregular sequence Watson and Crick proposed a double helix with sugar-phosphate backbones on the outside and bases aligned to the interior 2-8

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 DNA Helix Structure compared to a twisted ladder – Curving sides of the ladder represent the sugar-phosphate backbone – Ladder rungs are the base pairs – There are about 10 base pairs per turn Arrows indicate that the two strands are antiparallel

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 2-10

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 2-11 Transcription

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2-12 DNA Sigma factor Longer transcriptsShort transcripts Sigma RNA Promoter region Gene(s) to be transcribed (light green strand) RNA polymerase (core enzyme) Sigma recognizes promoter and initiation site Transcription begins; sigma released. RNA chain growth continues to termination site Termination site reached; chain growth stops Release of polymerase and RNA 1. 분자생물학 기초 - Translation PSTQ&feature=related

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Storing Information 2-13 Producing a protein from DNA information involves both transcription and translation – A codon is the 3 base sequence that determines what amino acid is used – Template strand is the complementary DNA strand that is used to generate the mRNA – Nontemplate strand is not used in RNA transcription

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Protein Structure Proteins are chain-like polymers of small subunits, amino acids – DNA has 4 different nucleotides – Proteins have 20 different amino acids with: An amino group A hydroxyl group A hydrogen atom A specific side chain

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Polypeptides Amino acids are joined together via peptide bonds Chains of amino acids are called polypeptides Proteins are composed of 1 or more polypeptides Polypeptides have polarity as does DNA – Free amino group at one end is the amino- or N-terminus – Free hydroxyl group at the other end is the carboxyl- or C-terminus

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Types of Protein Structure Linear order of amino acids is a protein’s primary structure Interaction of the amino acids’ amino and carboxyl groups gives rise to the secondary structure of a protein – Secondary structure is the result of amino acid and carboxyl group hydrogen bonding among near neighbors – Common types of secondary structure:  helix  sheet

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Helical Secondary Structure In  -helix secondary structure polypeptide, backbone groups form H bond with each other Dashed lines in figure indicate hydrogen bonds between nearby amino acids

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Sheet Secondary Structure The  -sheet pattern of 2° structure also occurs when polypeptide backbone groups form H bonds In the sheet configuration, extended polypeptide chains are packed side by side This side-by-side packing creates a sheet appearance

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Tertiary Structure Total three-dimensional shape of a polypeptide is its tertiary structure A prominent aspect of this structure is interaction of the amino acid side chains The globular form of a polypeptide is a roughly spherical structure

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Protein Domains Compact structural regions of a protein are referred to as domains Immunoglobulins provide an example of 4 globular domains Domains may contain common structural-functional motifs – Zinc finger – Hydrophobic pocket Quaternary structure is the interaction of 2 or more polypeptides Immunoglobulin

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 Protein Function Proteins: –Provide the structure that helps give cells integrity and shape –Serve as hormones carrying signals from one cell to another –Bind and carry substances –Control the activities of genes –Serve as enzymes that catalyze hundreds of chemical reactions

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 1. 분자생물학 기초 One-gene / One-polypeptide Over time many experiments have built on Garrod’s initial work Many enzymes contain more than one polypeptide chain and each polypeptide is usually encoded in one gene These observations have lead to the one gene one polypeptide hypothesis: Most genes contain the information for making one polypeptide

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 온도에 따른 미생물의 분류 - 저온성 미생물 (psychrophiles): 20 ℃이하에서 생장 - 중온성 미생물 (mesophiles): 20 ℃ ~30 ℃ 에서 생장 - 호열성 미생물 (thermophiles): 50 ℃ 이상에서 생장 생장 대상에서 산소를 요구하는 여부에 따른 분류 - 호기성 (aerobic): 생장과 대사에 산소 요구 - 협기성 (anaerobic): 산소에 의해 생장이 억제 - 통협기성 (faculative): 호기성과 혐기성 조건에서 모두 자랄 수 있게 대사 경로를 바꿀 수 있음. 모양에 따른 세포들의 분류 - 구균 (coccus): 구형과 타원형 모양 - 간균 (rod) 또는 bacillus: 원통형 모양 - spirillum: 나선형 모양

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 진핵 세포 (eucaryotic cell) - 복잡한 내부 구조를 가지며 핵 안에 하나 이상의 염색체가 존재함. - 핵막이 있으며 미토콘드리아, 소포체, 골지체와 같은 다양하게 분화된 세포 소기관을 갖고 있음. 원핵세포 (procaryotic cell) - 단일 염색체 (chromosome) 의 단순한 구조로 되어 있고 핵막이 없으며 미토콘드리아나 소포체 같은 세포 소기관이 없음.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 바이러스 - 매우 작으며 세포의 절대 기생체임 ~330nm 수준으로 유전물질로서 DNA 와 RNA 를 가짐. - 핵물질은 capsid 라는 단백질 껍질로 덮여 있음. - 어떤 바이러스는 lipoprotein 으로 된 외피를 가지고 있으나 없는 바이러스도 있음.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 바이러스 - Bacteriophage: 박테리아를 감염시키는 바이러스. Lytic cycle - 박테리오파지의 핵산은 숙주세포 안에서 복제되어 더 많은 파지를 만들어내고 바이러스 증식의 어떤 단계에서 숙주세포 는 용해되거나 터져서 파지입자를 방출하고 이 파지는 다른 숙주세포를 감염시킴. Lysogenic cycle - 파지 DNA 가 숙주 DNA 에 꺼이 들어가서 숙주세포와 함께 증식.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 원핵세포 (procaryote) - 반지름 : 0.5 – 3 µm - 구형을 구균 (coccus), 막대기 모양을 간균 (bacillus), 그리고 나선형 모양을 나선균 (spirillium) - 원핵세포는 double time 이 빠르고 탄수화물, 탄화수소, 단백질 및 CO 2 를 포함한 다양한 물질을 탄소원으로 이 용함.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 진정박테리아 (eubacteria) - 그람 염색법 : 세포벽의 구조의 차이로 인한 염색법 - 그람 음성 세포 : E. Coli 가 전형적인 예로 얇은 펩티도 글리칸 (peptidoglycan) 층에 의해 지지되는 외막을 가 지고 있음. - 그람 양성 세포 : Bacillus subtillis 가 대표적인 예임. 외박이 없지만 여러 층의 펩티도클리칸 층으로 된 두껍 고 단단한 세포벽을 지니고 있음. 세포질 막만 지니기 때문에 음성 세포에 비해 단백질 분비가 용이해서 단백질이 원하는 산물일 때 이러한 분 비력은 기술적인 장점이 됨.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 진핵세포 (eucaryote)

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 세포주기

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 – 항체

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 – 항체

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 – 단당류와 다당류 탄수화물 - 세포의 구조 물질과 저장물질로 중요한 역할. - 동물과 식물에서 화학적 신호 현상을 조절하는 역할. - 단당류는 가장 작은 탄수화물로 3 – 9 개의 탄소원자를 함유함. - 알데하이드형과 케톤형

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 – 단당류와 다당류 탄수화물 - D-ribose 와 deoxiribose - 5 개의 탄소원자를 갖는 환형 구조의 당분자. - DNA 와 RNA 의 필수적인 구성 성분.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 – 지질, 지방 스테로이드 지질 (Lipid) - 물에 녹지 않는 소수성을 띤 생체물질. - 벤젠, 클로로포름, 에테르와 같은 비극성 용매에 녹음. - 세포막과 같은 비수성 생체계에 존재함. - 생체의 연료 저장 역할을 담당.

DRUG DELIVERY SYSTEM & TISSUE ENGINEERING SOGANG UNIVERSITY 2. 생물의 다양성 – 핵산, RNA, DNA 뉴클레오타이드