This invention relates to modified hydroxylases. The invention further relates to cells expressing such modified hydroxylases and methods of producing hydroxylated alkanes by contacting a suitable substrate with such cells.

The present disclosure relates to fusion proteins including an iron-sulfur protein (e.g., cholesterol 7-desaturase (C7D)) and a ferredoxin reductase (e.g., KshB) that can efficiently convert cholesterol to 7-dehydrocholesterol (7-DHC) in vivo. Also disclosed herein are engineered microbes (e.g., E. coli) expressing the fusion proteins and methods of use thereof.

Compositions, methods, and systems for modifying sterol metabolism in a subject is disclosed. In some embodiments, the subjects may be administered one or more mammalian cells modified to express at least one sterol degrading enzyme derived from a bacterium. In many embodiments, the cell is a macrophage or monocyte stably expressing three or more enzymes that aid in opening the ring of cholesterol. The disclosed compositions and methods may be useful in lowering cholesterol levels in a subject in need thereof. In some embodiments, the subject may have a genetic predisposition to atherosclerosis.