Biopolymers: structure, synthesis and self-assembly

Chapter 1

Biopolymers: structure, synthesis and self-assembly

11 topics

  1. 1Origin and evolution of cells. Prokaryotes, eukaryotes, Escherichia coliHow the first atoms became the first cells, how a prokaryote such as E. coli differs from a eukaryotic cell, and where our mitochondria came from.
  2. 2Proteins. Protein domains. Protein familiesHow a chain of amino acids folds into a working protein, how large proteins are built from domains, and how proteins that share an ancestor form families.
  3. 3Nucleic acids. DNA. RNAWhat DNA and RNA are made of, how two strands of DNA wind into a double helix, and why RNA, with one extra oxygen, can fold, act and is soon broken down.
  4. 4Recognition and self-assembly of macromolecules. CytoskeletonHow molecules find their partners through many weak bonds, how subunits build large structures by themselves, and how the cytoskeleton's three kinds of filament shape the cell and move things within it.
  5. 5TranscriptionHow RNA polymerase copies a gene into RNA, how bacteria start and stop it with one enzyme, and how our cells share the work among three.
  6. 6RNA processingHow a new transcript in the nucleus becomes a working RNA, by capping, splicing and a poly(A) tail for mRNA and by cutting and trimming for rRNA and tRNA, and how one gene can give several proteins.
  7. 7Genetic code. TranslationHow the four-letter code of mRNA is read three bases at a time into the twenty amino acids of a protein, by tRNAs, their synthetases and the ribosome.
  8. 8Proteins after translation: sorting, folding, modifications, degradationWhere a new protein goes and how it gets there, how it folds and is checked, what is added to it, and how the cell destroys it when it is no longer wanted.
  9. 9DNA replicationHow a cell copies its DNA before it divides. Each strand is the template for a new one, two forks run from every origin, and the ends of our chromosomes need an enzyme of their own.
  10. 10RNA replication. Reverse transcriptionHow RNA viruses copy their genomes with a polymerase our cells do not make, why they change so fast, and how retroviruses, hepatitis B and our own cells copy RNA back into DNA.
  11. 11DNA repairHow a cell finds and mends the damage its DNA suffers every day, by cutting out the damaged stretch of one strand and copying the other or by rejoining broken ends, how damage stops the cell cycle, and what happens when repair fails.