[2] Braunstein's best-known work centered on enzymatic transamination and the role of vitamin B6 (specifically, in its pyridoxal phosphate form) as a cofactor in these reactions.
Along with Maria Kritzman, Braunstein co-discovered the phenomenon of transamination and described its biological significance in a series of papers beginning in 1937.
[3] Later, Braunstein's and Esmond Emerson Snell's research groups independently described a general catalytic mechanism for enzymes dependent on the biologically active form of vitamin B6, known as pyridoxal phosphate (PLP), as a cofactor.
[4] In his later career, Braunstein focused on X-ray crystallography, attempting to solve the structure of transaminase enzymes.
[5] In recognition of his contributions to the study of vitamin B6 biochemistry, the 1987 meeting in a regular series of international symposia on pyridoxal catalysis was dedicated to Braunstein's memory.