BIOL 116 Lecture Notes - Lecture 19: Francis Crick, Srb, Arginine
28 Nov 2016
School
Department
Course
Professor
Document Summary
Made bread mold mutants by exposure of spores to radiation and looked at phenotypic effects. Hypothesis: some mutants lack the enzymes to make specific compounds. One-gene, one-enzyme hypothesis: a gene contains the information needed to make an enzyme. Srb and horowitz examined production of aa arginine (required for growth) by bread mold by studying mutants. Arginine is end product of a metabolic pathway involving 3 enzymes. Predicted specific genes required for synthesis of each of the 3 enzymes. Finally understood what most genes do: contain instructions for making proteins. Francis crick: diff combinations of 4 bases of nucleotides could specify the 20 aa. But jacob and monod proposed an intermediary, rna, between dna and protein - suggested by eukaryotic cell structure. Dna (info storage) mrna (info carrier) proteins (active cell machinery) Some genes code for rna molecules (not mrna) that arent translated into proteins (trna, rrna)
