Well I know that he never appeared on the serie but he was one of the 12 founders of the Company and the father of Peter and Nathan Petrelli, I think that he haves an healing power or immortality since on the novel 63 "Elles First Assignment - Part 1" when Bob says " (...)with her blood, she might become a major player. The next lindermen. The next Arthur Petrelli." and we don't know if Arthur is dead because Linderman and Arthur were friends and the founders of the company, and on one of the episodes of the first season when Natan says that Arthur was killed by the other founder Linderman and a company man doesn't get caught so easily. So we might see Arthur in the future.
