Prepare the yeast liquid: mix the compressed yeast with the warm water until dissolved, or dissolve 1 teaspoon of the sugar in the warm water, sprinkle in the dry yeast and leave in a warm place until dissolved and frothy, for about 10 minutes.
Mix the all-purpose flour, bran, wheat germ and salt together in a large bowl.
Rub in the butter or margarine until the mixture resembles breadcrumbs, and then add the sugar.
Stir the molasses into the yeast liquid and add to the dry ingredients, mixing to form a soft dough. (At this stage it might be too sticky to handle but do not add more flour.) Cover the dough in the bowl and leave to rise until doubled in size.
Turn the dough out onto a lightly floured surface and knead for 5 minutes, adding a little extra flour if still too sticky to handle.
Shape to fit two well greased small 4 1/2 x2 1/2 x1 1/2-inch loaf pans.
Cover and let rise in a warm place for about 30 minutes.
Bake in the center of a moderate oven (350°F) for 30-35 minutes.
Turn out onto a cake rack and cool.