[Properties of mitochondrial porin from cattle heart]

Porin, a protein able to form ionic channels in model phospholipid membranes, has been isolated for the first time from bovine heart mitochondria. One-dimensional electrophoresis in the presence of sodium dodecyl sulfate revealed a major band with Mr of 32-34 kDa. On two-dimensional electrophoregrams this protein is represented by four components with pI ranging from 6.5 to 7.1. Porin spots were identified on two-dimensional electrophoregrams in a complete mixture of mitochondrial proteins. The presence of porin in bovine heart submitochondrial particles was demonstrated by two-dimensional electrophoresis.