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Penicillinase was the first β-lactamase to be identified. It was first isolated by Abraham and Chain in 1940 from E. coli (which are gram-negative) even before penicillin entered clinical use, [ 5 ] but penicillinase production quickly spread to bacteria that previously did not produce it or produced it only rarely.
Penicillin resistance in Staphylococcus aureus [3] appeared very soon after penicillin entered general clinical use in 1943, and the mechanism of resistance was the production of β-lactamase. Modification of the penicillin molecule so that it was resistant to being broken down by β-lactamase was able to temporarily overcome this problem.
β-Lactam antibiotics are indicated for the prevention and treatment of bacterial infections caused by susceptible organisms. At first, β-lactam antibiotics were mainly active only against gram-positive bacteria, yet the recent development of broad-spectrum β-lactam antibiotics active against various gram-negative organisms has increased their usefulness.
The β-lactam core structures. (A) A penam.(B) A carbapenam.(C) An oxapenam.(D) A penem.(E) A carbapenem.(F) A monobactam.(G) A cephem.(H) A carbacephem.(I) An oxacephem. This is a list of common β-lactam antibiotics—both administered drugs and those not in clinical use—organized by structural class.
The extended-spectrum penicillins are a group of antibiotics that have the widest antibacterial spectrum of all penicillins. [1] Some sources identify them with antipseudomonal penicillins, [2] others consider these types to be distinct. [3] This group includes the carboxypenicillins and the ureidopenicillins.
Penicillin can easily enter bacterial cells in the case of Gram-positive species. This is because Gram-positive bacteria do not have an outer cell membrane and are simply enclosed in a thick cell wall. [45] Penicillin molecules are small enough to pass through the spaces of glycoproteins in the cell wall.
In France, an "Antibiotics are not automatic" government campaign started in 2002 and led to a marked reduction of unnecessary antibiotic prescriptions, especially in children. [ 114 ] The emergence of antibiotic resistance has prompted restrictions on their use in the UK in 1970 (Swann report 1969), and the European Union has banned the use of ...
Penicillinase is a bacterial enzyme produced by bacteria resistant to other β-lactam antibiotics which hydrolyses the antibiotic, rendering it non-functional. Methicillin is not bound and hydrolysed by penicillinase, meaning it can kill the bacteria, even if this enzyme is present.