Lesson 6

Cards (70)

  • Archibald Garrod is and English physician who related gene and enzyme
  • Garrod studied Alkaptonuria
  • Alkaptonuria is when urine turns black when exposed to air
  • George Beadle and Edward Tatum discovered one gene one enzyme hypothesis
  • An enzyme catalyzes a step in a metabolic reaction
  • One gene one protein:
    Not all proteins are enzymes. They are gene products
  • Gene contains info for making one RNA
  • Promoter is a DNA sequence which transcription enzyme binds
  • RNA polymerase is the MAIN enzyme for transcription
  • One gene one polypeptide
    • Hemoglobin has 2 alpha and beta chains
  • Enzymes catalyze metabolic reactions
  • Gene contains information for 1 RNA and polypeptide
  • Promoter is a DNA sequence which transcription enzyme binds
  • RNA polymerase is the main enzyme for transription
  • Prokaryotic transcription has 10 seq of TATAAT and 35 seq of TTGACA
  • Products of transcription: RNA Types
    Messenger RNA (mRNA) carries the message
  • Products of transcription: RNA Types
    transfer RNA (tRNA) brins amino acids to synthesis site
  • Products of transcription: RNA Types
    ribosomal RNA (rRNA) is major component of ribosomes
  • In prokaryotic ribosome: 70S
    30S (Svedberg value) with 16 S rRNA and 21 ribosomal proteins
  • In prokaryotic ribosome: 70S
    50 S with 23 S rRNA , 5 S rRNA, 31 ribosomal proteins
  • In eukaryotic ribosome: 80 S
    mammalian has 40S with 18S rRNA + 30-35 proteins
  • In eukaryotic ribosome: 80 S
    60S with 5.8S rRNA + 28S + 5S rRNA + 40-45r proteins
  • In eukaryotic transcription, promoters have 25-30 TATA box or Goldberg-Hogness Box and 75-80 CAAT box
  • Codon is a 3 base sequence in mRNA
  • Anticodon is a 3 base sequence in a tRNA
  • Genetic code is a set of 64 codons
  • Polypeptide is a single protein chain
  • Formula for Translation:
    mRNA + Ribosomes + tRNAs with aa
  • George Gamow proposed genetic coding system
  • Marianne Grunberg-Manago and Severo Ochoa made synthetic RNAs using polynucleotide phosphorylase
  • Marshall Nirenberg and Johann Heinrich Matthaei produced artificial mRNA and cell free system
  • poly U (UUU) = polyphenylalanine
  • Poly C (CCC) = proline
  • Har Gobind Khorana constructed different repeating nucleotide combinations (UCU, CUC)
  • Characteristic of genetic code:
    • triplet code
    • continuous
    • non overlapping
    • universal
    • degenerate
    • start and stop signals
    • wobble in anticodon
    • unambigous
  • Yanofsky = linear correspondence in DNA seq and amino acids
  • Genomics refers to molecular analysis of entire genome of species
  • Genomics is possible due to rapid development of genetic technology
  • 2 types of genomics
    • structural
    • functional
  • structural genomics is the direct analysis of DNA itself