Using Conformational Analysis to Identify Structurally Conserved Regions of MAP Peptides that Exhibit Cellular Attachment Ability

A natural bioadhesive obtained from Mytilus edulis , mussel adhesive protein, MAP or mefp-1, is frequently used for cellular attachment. MAP is approximately 114 kD, and generally composed of repeating decapeptide units, A-K-P-S-Y-Hyp-Hyp-T-DOPA-K, MAP-RD. Prior nuclear magnetic resonance (NMR) spectroscopy and molecular modeling of MAP-RD revealed an overall bent-helix. NMR spectroscopy and molecular modeling of a MAP fourteen residue peptide, P-S-Y-Hyp-Hyp-T-Y-K-A-K-P-S-Y-Hyp, MAP-14, are presented. Additionally, a molecular model built and minimized from MAP-RD and MAP-14 produced a twenty-six-residue MAP peptide, (MAP-26), that maintained regional structural consistency with both MAP-RD and MAP-14. Multiple attenuated internal reflection infrared (MAIR-IR) spectroscopy and ellipsometry of the MAP-14 as well as that of L-DOPA-containing MAP-14, (MAP-14(D)), showed uniform film formation near a monolayer in thickness was L-DOPA dependent. Significantly more undifferentiated leukocyte cells (MOLT-4) attached to and spread on MAP-14 (D) films (applied at 2 w g cm m 2 ) compared with intact MAP, MAP-RD or tissue culture treated polystyrene, indicating a cellular binding domain presence in the MAP-14 sequence. The culmination of biophysical data indicate the lysine-alanine-lysine (K-A-K) sequence as structurally conserved and responsible for the cellular attachment ability noted for MAP14(D) and ultimately MAP.

Keywords:

• Bioadhesives
• Mussel Adhesive Protein
• Nuclear Magnetic Resonance
• Peptides