Sir Alexander Fleming (6 August 188111 March 1955) was a Scottish biologist

Biologist

A biologist is a scientist devoted to and producing results in biology through the study of life. Typically biologists study organisms and their relationship to their environment. Biologists involved in basic research attempt to discover underlying mechanisms that govern how organisms work...

 and pharmacologist. He wrote many articles on bacteriology, immunology, and chemotherapy. His best-known discoveries are the discovery of the enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

 lysozyme

Lysozyme

Lysozyme, also known as muramidase or N-acetylmuramide glycanhydrolase, are glycoside hydrolases, enzymes that damage bacterial cell walls by catalyzing hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between...

 in 1923 and the antibiotic

Antibiotic

An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...

 substance penicillin

Penicillin

Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

 from the mould Penicillium notatum in 1928, for which he shared the Nobel Prize in Physiology or Medicine

Nobel Prize in Physiology or Medicine

The Nobel Prize in Physiology or Medicine administered by the Nobel Foundation, is awarded once a year for outstanding discoveries in the field of life science and medicine. It is one of five Nobel Prizes established in 1895 by Swedish chemist Alfred Nobel, the inventor of dynamite, in his will...

 in 1945 with Howard Florey and Ernst Boris Chain

Ernst Boris Chain

Sir Ernst Boris Chain was a German-born British biochemist, and a 1945 co-recipient of the Nobel Prize for Physiology or Medicine for his work on penicillin.-Biography:...

.

In 1999, Time

Time (magazine)

Time is an American news magazine. A European edition is published from London. Time Europe covers the Middle East, Africa and, since 2003, Latin America. An Asian edition is based in Hong Kong...

magazine named Fleming one of the 100 Most Important People of the 20th Century

Time 100: The Most Important People of the Century

Time 100: The Most Important People of the Century is a compilation of the 20th century's 100 most influential people, published in Time magazine in 1999....

 for his discovery of penicillin

Penicillin

Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

, and stated:
Fleming was born on 6 August 1881 at Lochfield, a farm near Darvel

Darvel

Darvel is a small town in East Ayrshire, Scotland, located at the eastern end of the Irvine Valley and is sometimes referred to as "The Lang Toon" due to its quaint appearance on Ordnance Survey maps....

 in Ayrshire

Ayrshire

Ayrshire is a registration county, and former administrative county in south-west Scotland, United Kingdom, located on the shores of the Firth of Clyde. Its principal towns include Ayr, Kilmarnock and Irvine. The town of Troon on the coast has hosted the British Open Golf Championship twice in the...

, Scotland.