Acid phosphatases bind to the main high density lipoprotein apolipoprotein A‐I

Abstract

The serum protein binding secretory prostatic acid phosphatase (PAP) and lysosomal placental acid phosphatase (LAP) was purified using affinity chromatography on gels containing immobilized acid phosphatases. The protein, which could be eluted from these enzyme affinity gels only with 0.05 HCl (pH 2.0), was shown to be apolipoprotein A‐I (apo A‐I), the main structural protein of high density lipoprotein (HDL).

Apolipoprotein A‐I‐binding protein from human term placenta Purification and partial characterization

“…Why this protein also interacts with L-(+)-tartrate is not known at present. This latter interaction which has been considered rather specific for the tartrate-inhibitable lysosomal acid phosphatase (LAP) led us to believe that this enzyme also binds the apolipoprotein A-I [14]. However, the present study clearly demonstrates that the LAP activity can be separated from the apoA-I-BP.…”

“…We recently reported that acid phosphatases avidly bind to the main high density lipoprotein apoprotein A-1 [14]. However, further studies indicate that apoA-I does not bind to the enzyme but to a protein that co-elutes with the enzyme during affinity chromatography on L-(+)-tartrate.…”