Antibiotic resistance in gonorrhea Antibiotic resistance in gonorrhea The Gonorrhea bacterium Neisseria gonorrhoeae has developed antibiotic resistance to many antibiotics. The bacteria was first identified in 1879, although some Biblical scholars believe that references to the disease can be found as early as Parshat Metzora of the Old Testament. In the 1940s effective treatment with penicillin became available, but by the 1970s resistant strains predominated. Resistance to penicillin has developed through two mechanisms: chromasomally mediated resistance (CMRNG) and penicillinase-mediated resistance (PPNG). CMRNG involves step wise mutation of penA, which codes for the penicillin-binding protein (PBP-2); mtr, which encodes an efflux pump that removes penicillin
A22 (antibiotic) A22 (antibiotic) A22, also known as "S"-(3,4-dichlorbenzyl)isothiourea, is a chemical compound with antibiotic activity. It is colorless, hygroscopic, and light-sensitive. A22 acts as a reversible inhibitor of the bacterial cell wall protein MreB, causing bacterial rod-shaped cells to form coccoid cells. The antibiotic activity of A22 has been studied primarily in "Pseudomonas aeruginosa." However, A22 does not seem to be useful as an antibiotic in humans due to its cytotoxic and genotoxic effects on human peripheral blood mononuclear cells (PBMCs). Despite its cytotoxic effects in human cells, A22 has been used as a research tool to investigate the bacterial cytoskeleton.