although density ultracentrifugation revealed the presence of traces of a high-density lipoprotein in bovine serum fraction , another , less dense component , isolated by ultracentrifugation ( component 3 ) and containing cholesterol , cholesteryl esters , free fatty acids , triglycerides , and protein , but no lipoprotein , exhibited considerably more growth-supporting activity than did the high-density lipoprotein , thus indicating that at least two mycoplasma species do not require intact serum lipoprotein for growth .
C0008377
cholesterol
C0008387
cholesteryl esters