Alexander Fleming, Biopioneer Strive For Excellence: He used his powers of observation to change medicine.(LEADERS & SUCCESS)

Byline: DONNA HOWELL

Nobel Prize-winning bacteriologist Sir Alexander Fleming knew potential when he saw it. When he discovered penicillin by chance, he realized its possibilities. When he pursued them, he made history.

Throughout life, Fleming stood by certain virtues that helped him succeed. He pursued truth, relished vision, believed in teamwork and wanted to help his fellow man.

He had "the ability to take advantage of a chance," said Kevin Brown, curator of the Alexander Fleming Laboratory Museum at St. Mary's Hospital in London.

Fleming was born a farmer's son in Lochfield, Scotland, in 1881. He was the seventh of eight children.

"We unconsciously learned a great deal from nature," Fleming said of his childhood. But he kept learning from nature in his adult work.

Early on, Fleming was a dedicated student and felt called to the medical profession. So he trained for it at St. …