Halogens and Their Role in Stabilizing Proteins of the Jaws of a Marine Worm, Nereis

As explored. The outer surface coating of the jaw-tip appeared to have a granular morphology (∼ 3 to 8 pm thick), in contrast to the anisotropic, fibrous core that dominates the sub-architecture. Given the narrow distributions of some metals in the granular jaw coating, it is possible that they contribute to mechanical properties such as wear. Furthermore, using analytical techniques such as chromatography and mass spectrometry we have found that the halogens are associated with proteins in the jaw. Halogenated histidine, tyrosine, dityrosine and trityrosine amino acids have been characterized. Several modified amino acids have been discovered here for the first time: di-bromo-histidine, bromo-iodo-histidinc, chloro-iodo-tyrosine, bromo-iodo-tyrosine, chloro-di-tyrosine, chloro-tri-tyrosine, chloro-bromo-tri-tyrosine and bromo-iodo-tri-tyrosine. Inspired from the new knowledge obtained thus far, the role of bromination in Nereis jaws was explored with an imidazole model system. The.