FIG. 2.

Subclones of the original isolate PH3⁶ and complementation analysis. All growth experiments and [¹⁴C]cholesterol uptake assays were performed as described in Materials and Methods. Cholesterol uptake is expressed as micrograms of cholesterol per milligram (dry weight) of cells. SC2-1C (upc2-1) was transformed with each plasmid and tested for CaCl₂ tolerance and sterol uptake. Each measurement is representative of the result of an independent assay, and all cultures were grown in duplicate. Controls for these experiments were strains 463-1C (UPC2) and SC2-1C (upc2-1). pFE5k-1 and pFE7k-10 fragments were isolated from the original 10-kb insert. Subsequent subclones were obtained from the 7.2-kb insert of pFE7k-10 (hence the absence of restriction sites from the diagram). N.A., not applicable.