Marshall Nirenberg in his office at the NIH, 1960.
Marshall Nirenberg at the White House explaining the genetic code to President Lyndon Johnson.
Marshall Nirenberg at the NIH, 1999. He is holding one of the original charts with 'code-cracking' data.
Marshall Nirenberg, National Institute of Health, 1960.
1966 Cold Spring Harbor Symposium on protein synthesis. (L-R) Marshall Nirenberg, B. P. Doctor, C. T. Caskey.
Marshall Nirenberg and Heinrich Matthaei used poly-U mRNA in a cell-free system to make a polyphenylalanine protein chain. This showed that UUU must be the code that specifies the amino acid phenylalanine.
Explaining the experiment to determine the RNA able to direct the synthesis of proteins.
Discovering that polyU directs the synthesis of polyPhenylalanine.
Working out the base compositions for the codons in the genetic code.
Using charged tRNAs to prove triplet nature of the genetic code, and to determine the base sequences of codons