Genetic heterogeneity in Pneumocystis carinii: an introduction

The molecular structure of free radicals formed in gamma-irradiated orthorhombic single crystals of hydrated testosterone was investigated by Electron Nuclear Double Resonance (ENDOR) spectroscopy. Only one kind of radical was observed, which is formed by addition of hydrogen atom to oxygen atom O(3). We observed interaction of the unpaired electron, which is delocalized on the carbons C(3), C(4) and C(5), with one alpha-proton in position 4 and with four unequivalent beta-protons connected with the carbon atoms C(2) and C(6). The matrices of the hyperfine couplings and the g-factor of the radical are given.