Biotechnology is a field of applied biology and

• Biotechnology is a field of applied biology and biochemistry, that involves the use of living organisms and bioprocesses in engineering, technology, medicine and other fields requiring bioproducts. • Modern world use similar term includes genetic engineering as well as cell- and tissue culture technologies. • Biotechnology draws on the pure biological sciences (genetics, microbiology, animal cell culture, molecular biology, biochemistry, embryology, cell biology) and in many instances is also dependent on knowledge and methods from outside the sphere of biology (chemical engineering, bioprocess engineering, information technology, biorobotics).

Major events in the history of Biotechnology • 1865 Gregor Mendel discover the basic rules of heredity of garden pea. – An individual organism has two alternative heredity units for a given trait (dominant trait v. s. recessive trait) • 1869 Johann Friedrich Miescher discovered DNA and named it nuclein. Mendel: The Father of Genetics Johann Miescher

Major events in the history of Biotechnology 1952 - 1960 • 1952 -1953 James D. Watson and Francis H. C. Crick deduced the double helical structure of DNA • 1956 George Emil Palade showed the site of enzymes manufacturing in the cytoplasm is made on RNA organelles called ribosomes. James Watson and Francis Crick George Emil Palade

The Central Dogma of biotechnology and Genetic Engineering A key of applied biochemistry Proposed by Francis Crick in 1958 to describe the flow of information in a cell. DNA RNA Protein Information stored in DNA is transferred residue-by-residue to RNA which in turn transfers the information residue-by-residue to protein. The Central Dogma was proposed by Crick to help scientists think about molecular biology. It has undergone numerous revisions in the past 45 years.

RNA: Structure 1. 2. 3. 4. RNA can be single or double stranded G-C pairs have 3 hydrogen bonds A-U pairs have 2 hydrogen bonds Single-stranded, double-stranded, and loop RNA present different surfaces

Compartmentalization of processes (thus, transport is important) replication

The Central Dogma (gene) ATGAGTAACGCG TACTCATTGCGC Replication duplication of DNA using DNA as the template ATGAGTAACGCG TACTCATTGCGC DNA (nontemplate, antisense) (template, sense) + ATGAGTAACGCG TACTCATTGCGC Transcription synthesis of RNA using DNA as the template (m. RNA) AUGAGUAACGCG codon RNA t. RNA ribosomes Translation (protein) synthesis of proteins using RNA as the template Protein Met. Ser. Asn. Ala

The Central Dogma Replication DNA Repair and recombination Transcription RNA processing RNA 1. Eukaryotic DNA pol and 2. DNA pol and 1. 2. 3. RNA pol I-ribosomal RNA (r. RNA) RNA pol II-messenger RNA (m. RNA) RNA pol III-5 S r. RNA, sn. RNA, t. RNA 1. 2. 3. m. RNA splicing r. RNA and t. RNA processing capping and polyadenylation Translation 1. Post-translational modification 2. Protein 3. phosphorylation methylation ubiquitination

Differences between eukaryotic and prokaryotic gene expression 1. In eukaryotes, one m. RNA = one protein. (in bacteria, one m. RNA can be polycistronic, or code for several proteins). 2. DNA in eukaryotes forms a stable, compacted complex with histones. (in bacteria, the DNA is not in a permanently condensed state) 3. Eukaryotic DNA contains large regions of repetitive DNA. (in bacteria, DNA rarely contains any "extra" DNA) 4. Much of eukaryotic DNA does not code for proteins (~98% is non-coding in humans) (in bacteria, often more than 95% of the genome codes for proteins) 5. Sometimes, eukaryotes can use controlled gene rearrangement for increasing the number of specific genes. (in bacteria, this happens rarely) 6. Eukaryotic genes are split into exons and introns. (in bacteria, genes are almost never split) 7. In eukaryotes, m. RNA is synthesized in the nucleus and then processed and exported to the cytoplasm. (in bacteria, transcription and translation can take place simultaneously off the same piece of DNA)