Lecture, three hours; discussion, one hour. Requisites: courses 153A (or 153AH), 171. Role of metal ions in biology. Topics include interactions of metal ions and metallocofactors with proteins, nucleic acids, and other biological molecules; mechanisms of metal ion transport and storage; metallocofactor biosynthesis; hydrolytic chemistry; biological electron transfer; metalloenzymes; metals in medicine. Concurrently scheduled with course C279. P/NP or letter grading.