The effect of trypsin and heat treatment on oxidative phosphorylation in Mycobacterium phlei

Abstract

The electron transport particles from Mycobacterium phlei contain particle-bound coupling factors and require the addition of soluble coupling factors for restoration of phosphorylation. However, exposure of the particles to heat (50°) or treatment with trypsin increased the P/O ratio with succinate or with NAD +-linked substrates. In addition, the heat treated particles no longer required the soluble coupling factors for phosphorylation, but the trypsin-treated particles required this addition for maximal levels of phosphorylation. A combination of treatment with trypsin and heat resulted in higher levels of phosphorylation than either treatment alone. The phosphorylation observed in both cases was sensitive to uncoupling agents.