Pbp target.

Penicillin was discovered accidentally in 1929 when Sir Alexander Fleming observed bacterial

crops contaminated form, which prevents bacterial growth. Antibiotic penicillin

was subsequently isolated from the culture Penicillium form.

In 1938, two British scientists, Howard

Flory and Ernst Cheney, first used purified preparations of penicillin

treatment of bacterial infections. Penicillin may be present in the national

tools that are used more in 600

BC, about this time molded soybean curd was used Chinese

treat abscesses and boils, and as moldy cheese was used Chinese and

Ukrainian peasants to treat infected wounds. Initially it was thought that penicillin was pure substance, but still

Research has shown that some closely related compounds present in

cultures Penicillium. Natural penicillins such as penicillin G, the most

effective against gram-positive bacteria, but much less effective against

Gram-negative bacteria. Another limitation to the use of penicillin G is

, that is not well absorbed by ingestion. Research Program

to produce chemically modified penicillin with improved properties

by a large number of clinically useful derivatives of penicillin. Examples of such derivatives of penicillin include ampicillin and amoxicillin

, with much higher efficacy against gram-negative bacteria than penicillin

, retain good activity against gram-positive bacteria

, and well absorbed when administered orally. Main >> << adverse reactions associated with penicillin is the existence

allergic reaction. Molecular targets for antibacterial activity of penicillin and related

lactam antibiotics such as cephalosporins are a group of bacterial enzymes

known as penicillin-binding proteins (PSB). PSB are important for the final stage of bacterial cell wall biosynthesis >>. << Penicillin and other antibiotics >> << lactam prevent PSB, thus inhibiting bacterial cell wall biosynthesis

, which eventually leads to bacterial cell lysis >>. << (Vancomycin and cycloserine is nonpenicillin antibiotics that also inhibit bacterial

biosynthesis of cell wall through other mechanisms).

-Penicillins and related antibiotics are among the most widely used therapeutic

means since their introduction into clinical practice

1940's. However, widespread use of antibiotics resulted in

in the emergence and spread of bacteria resistant to these agents

. main mechanism of resistance to penicillin and other antibiotics >> << lactam production is bacterial-lactamases, enzymes that split

-lactam antibiotics and make them inactive before they can prevent th

PBP target. Considerable efforts have been made to develop

lactam antibiotics resistant to-lactamases, and to search >> << lactamase inhibitors purchase strattera to-lactam antibiotics to be useful antimicrobials against-lactamase bacteria. .