Figure 6.
Figure 6. Proposed model for anchoring of PON1 to the surface of
HDL. (a) Tertiary structure cartoon of rePON1 showing its
exposed hydrophobic surfaces. N-terminal residues 7 -18, missing
in the crystal structure and predicted to be helical, were
modeled as part of H1. Denoted are all the hydrophobic residues
(leucine, phenylalanine, proline, isoleucine, tyrosine,
tryptophan and valine) appearing with accessible surface area
20
Å2. (b) Hydrophobic residues proposed to be involved in HDL
anchoring (side chains yellow). The line defined by the side
chains of Tyr185, Phe 186, Tyr190, Trp194, Trp202 (helix H2 and
the adjacent loops) and Lys21 (helix H1) models the putative
interface between HDL's hydrophobic interior and the exterior
aqueous phase. The hydrophobic side chains of leucine and
phenylalanine residues of H1 are primarily within the apolar
region31. The active site and the selectivity-determining
residues (Table 2) are blue, and the proposed glycosylation
sites (Asn253 and Asn324) are red.
20
Å2. (b) Hydrophobic residues proposed to be involved in HDL
anchoring (side chains yellow). The line defined by the side
chains of Tyr185, Phe 186, Tyr190, Trp194, Trp202 (helix H2 and
the adjacent loops) and Lys21 (helix H1) models the putative
interface between HDL's hydrophobic interior and the exterior
aqueous phase. The hydrophobic side chains of leucine and
phenylalanine residues of H1 are primarily within the apolar
region31. The active site and the selectivity-determining
residues (Table 2) are blue, and the proposed glycosylation
sites (Asn253 and Asn324) are red.