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.biologyengineering technologymedicine Modern world use similar term includes genetic engineering as well as cell- and tissue culture technologies.genetic engineering cell-tissue culture 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).genetics microbiologyanimal cell culturemolecular biologybiochemistry embryologycell biologychemical engineeringbioprocess engineeringinformation 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 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 RNA Protein DNA Proposed by Francis Crick in 1958 to describe the flow of information in a cell. 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.

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

Compartmentalization of processes (thus, transport is important) replication

The Central Dogma Transcription Translation Replication RNA Protein DNA duplication of DNA using DNA as the template synthesis of RNA using DNA as the template synthesis of proteins using RNA as the template ATGAGTAACGCG TACTCATTGCGC ATGAGTAACGCG TACTCATTGCGC ATGAGTAACGCG TACTCATTGCGC + AUGAGUAACGCG MetSerAsnAla (nontemplate, antisense) (template, sense) (mRNA) (protein) (gene) tRNA ribosomes codon

The Central Dogma Transcription RNA processing Translation Post-translational modification Replication Repair and recombination RNA Protein DNA 1. RNA pol I-ribosomal RNA (rRNA) 2. RNA pol II-messenger RNA (mRNA) 3. RNA pol III-5S rRNA, snRNA, tRNA 1. mRNA splicing 2. rRNA and tRNA processing 3. capping and polyadenylation 1. Eukaryotic DNA pol  and  2. DNA pol  and  1. phosphorylation 2. methylation 3. ubiquitination

1. In eukaryotes, one mRNA = one protein. (in bacteria, one mRNA 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, mRNA 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) Differences between eukaryotic and prokaryotic gene expression