Penicillin is the name of more than one artist:

1) Japanese group

2) German jazz-rock group

1) ＰＥＮＩＣＩＬＬＩＮ is a Japanese Rock band who formed in 1992 in Kanagawa, Japan.

The members consist of vocalist HAKUEI, guitarist 千聖 (Chisato), bassist GISHO, and drummer O-JIRO.

Their first offical release was PENICILLIN SHOCK which was released on May 30, 1994. Their most recent release was the album BLUE HEAVEN on February 28, 2007. On March 09, 2007 Gisho announced that he would be leaving PENICILLIN for personal reasons. Their last live as the foursome that has existed since 1993 was held on May 20, 2007. PENICILLIN has gone on without Gisho, and Gisho is continuing his full time job of managing Omega Project Holdings. As of the fall 2007 Kato Hiroki of The ROMEO and ex-Media Youth has been providing live support for the band.

Each of Penicillin's Members have several other projects. O-JIRO has the bands 808(Which he's the vocalist for) and STARMAN, Gisho is also involved in STARMAN and has done various solo works under both the name GISHO and Ohtaki Jun. 千聖's projects include his SOLO works under that name, the band crack6 where he's the vocalist and lead guitarist, and most recently his work with Hakuei on PENICLLIN- NANO. Hakuei's had a Solo Career, but has also worked with KIYOSHI in the project MACHINE. His most recent project announcement is entitled The LEGENDARY SIX NINE with Ruka of Nightmare.

http://www.penicillin.jp/

2) Penicillin were a German band (based in the town of Kottweiler) rooted in jazz-rock.
Formed in 1971 by Fred Felder (vocals) and Waldemar Ruth (drums), they had changed a lot over the years before their debut recordings. This was down to the fact that the band was often a large metamorphic troupe of up to 12 or 15 musicians, based around a pretty constant core of five, and that they'd experimented with everything from Hörspiel through to classical, combining such elements into their own unique sound.
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