Lecture 2 Slides Flashcards
Bacterial cell innovations
Ribosomes, translation
Phospholipids
Nucleic acids, DNA replication, transcription
Core metabolism (eg, glycolysis)
Homologous traits
Shared traits inherited from a common ancestor
Archaea innovations
Actin cytoskeleton
N linked glycans
Core histone
Proteasome
Eukarya innovations
Endo membranes (nucleus, ET, Golgi) Mitochondria endosymbiotic (gamma-proteobacteria) Cilia Sphingolipids Sterols (eg cholesterol)
Methods of evolution of eukaryotic genomes
Intragenic mutation
Gene duplication
DNA segment shuffling
Horizontal transfer
What caused eukaryotic genomic expansion
Noncoding DNA
Orthologs
One gene breaks into two homologous ones, one each for two new species . Inherited vertically, not from duplication. Presumed to have same function,
Paralogs
Duplication and divergence of a gene. Exist in same species.
Have different, specialized functions
HSP70
Genes encoding Hsp70s in organisms from all three major branches were derived from a common ancestral gene
Folding and interactions beyond protein primary structure are made by
Noncovalent bonds
Types of noncovalent bonds
Electrostatic interactions
Hydrogen bonds
Hydrophobic forces
Van der waals attractions
What do secondary structure folding patterns depend on
On hydorgen bonding bet. N-H and C=O groups in the backbone;are independent of side chains
Protein domain
A sequence that folds into a thermodynamically stable structure under physiological conditions and has a particular function
Intrinsically unstructured polypeptides
Lack tertiary structure
Where do covalent disulfide bonds form
Between cysteine side chains within one polypeptide chain or between two polypeptides but cannot form in reducing environment of cytosol.
Major types of proteins
Enzymes
Structural elements
Polymerases, ligases, synthases
Build up biological polymers and biochemicals
Hydrolysis and lyases
Break down biological polymers and biochemicals
Phosphatases
Remove phosphate groups
Isomerases
Move chemical groups around on a molecule