bioinformatics gene introduction 2 2003 oct ntust
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BioinformaticsGene
Introduction 22003 OctNTUST
Key Organic Molecules Are Used By Living Systems
Many Components of Biochemical Macromoleculaes Can Be Produced in Simple Prebiotic Reactions ~1 billions years after
Earth’s formation, life appeared.
The Urey-Miller experiment.
1950, Stanley Miller and Harold Urey
Products of Prebiotic Synthesis
Amino Acids Produced in the Urey-Miller experiment.
Prebiotic Synthesis of a Nucleic Acid Component
Adenine can be generated by the condensation of HCN.
Genetic Material A nucleotide contains :
A five-carbon sugar molecules One or more phosphate groups A nitrogenous base
Ribose and Deoxyribose
Backbone of DNA and RNA
Purines and Pyrimidines
Watson-Crick base pairs
Watson-Crick base pairs
X-ray Diffraction Photography of a Hydrated DNA Fiber
Watson-Crick Model of Double Helical DNA
The Double Helix
DNARNAProtein
Complementarity Between mRNA and DNA
Promoter Sites for Transcription- Prokaryotic Genes
Promoter Sites for Transcription-Eukaryotic Genes
RNA Template-directed Polypeptide Synthesis Links the RNA and Protein Worlds (I)
I
RNA Template-directed Polypeptide Synthesis Links the RNA and Protein Worlds (II)
II
III
Attachment of a Amino Acid to a tRNA Molecule
Symbolic Diagram of an Aminoacyl-tRNA
The Features of the Genetic Code
Three nucleotides encode an amino acid
The code is nonoverlapping The code has no punctuation The genetic code is degenerate
The code is nonoverlapping
The code has no punctuation
The genetic code is degenerate
Initiation of Protein Synthesis-Prokaryotes
Initiation of Protein Synthesis-Eukaryotes
Transcription and Processing of beta-globin Gene
Consensus Sequence for the Splicing of mRNA Precursors
BioinformaticsEvolution
Structural Similarity Often Follow Functional Similarity
Angiogenin is Highly Similar to Ribonuclease
Two Classes of Homologs
Amino Acid Sequences
Alignment with Gap Insertion
The Generation of a Shuffled* Sequence
* Randomly rearranged
Statistical Comparison of Alignment Scores
A Graphic View of the Blosum-62 Substitution Matrix
Alignment with Conservative Substitutions Noted
The odds: 1/20 The odds: 1/300
Alignment of Myoglobin and Leghemoglobin
23% identical
Database Can Be Searched to Identify Homologous Sequences
database
Tertiary Structure Is More Conserved Than Primary Structure
The Structures of Actin and Hsp-70
Heat Shock Protein 70: assists protein folding
Cytoskeleton
Convergent Evolution of Protease Active Site
Structures of Chymotrypsin and Subtilisin
Evolutionary Trees Can Be Constructed On the Basis of Sequence Information