How was Dorothy Crowfoot Hodgkin awarded the Noble Prize?

Name: Dorothy Crowfoot Hodgkin. 
Country: American.
Date of Birth: 12 May 1910.
Date of Death: 29 July 1994.
The subject of Study: Penicillin pepsin sterol vitamin B12.
Noble Prize Year: Nobel Prize for Chemistry in 1964 for his research the development of structural biology required the use of X-ray crystallography to determine the structures of biomolecules.