Tooth enamel protein, amelogenin, has a probable beta-spiral internal channel, Gln112-Leu138, within a single polypeptide chain: preliminary molecular mechanics and dynamics studies.
Molecular dynamics simulation, with backbone constraints for 20 ps of equilibration and simulation, of a repeating polypeptide segment, Gln-Pro-His-Gln-Pro-Leu-Gln-Pro-His-Gln-Pro-Leu-Gln-Pro-Met-(Gln-Pro-Leu )4, constituting residues 112-138 of bovine amelolgenin, a 19.35 kD hydrophobic protein, are discussed. It is generally believed that the above polypeptide segment is important for the interaction of amelogenin with Ca++ ions, which occurs in the early phases of enamel mineralization. An energetically stable structure of the above polypeptide with recurrent beta-turns is observed and contains a pore of approximately 1 A radius along the helical that can accommodate an unhydrated Ca++ ion. The length of the polypeptide possesses correct dimensions to span a bilayer. The proposed structure is unique among known polypeptide and protein structures.
Renugopalakrishnan
V
V
Pattabiraman
N
N
Prabhakaran
M
M
Strawich
E
E
Glimcher
M J
MJ
D053523:Amelogenin; D000595:Amino Acid Sequence; D003746:Dental Enamel Proteins / Q000502:physiology*; D008969:Molecular Sequence Data; D011487:Protein Conformation; D014083:Tooth Germ
D053523:Amelogenin; D003746:Dental Enamel Proteins