DISTRIBUTION OF MOLYBDENUM 99 IN CELL-FREE PREPARATIONS OF AZOTOBACTER VINELANDII

Abstract
A particulate fraction was obtained from cell-free preparations of Azotobacter vinelandii by centrifugation for 6 hours at 144,000 x g. This particulate fraction has a Mo" to protein ratio higher than any other fraction, a high 260 mu/280 mu ratio, and contains a large percentage of the Mo taken up by the cells.