Open AccessSB 205952, a novel semisynthetic monic acid analog with at least two modes of action
Author(s) -
Jenny Wilson,
B Oliva,
Robert Cassels,
Peter J. O’Hanlon,
Ian Chopra
Publication year - 1995
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.39.9.1925
Subject(s) - mupirocin , microbiology and biotechnology , chemistry , mechanism of action , antibacterial agent , antimicrobial , biology , antibiotics , biochemistry , bacteria , staphylococcus aureus , in vitro , methicillin resistant staphylococcus aureus , genetics
The biological properties of SB 205952, a nitrofuryl oxazole derivative of monic acid, differ from those of the closely related antibacterial agent mupirocin. Compared with mupirocin, SB 205952 has increased antimicrobial potency, an extended spectrum including mupirocin-resistant staphylococci, and rapid bactericidal activity. SB 205952, like mupirocin, is a potent inhibitor of bacterial isoleucyl-tRNA synthetase (IRS) in mupirocin-susceptible organisms but does not inhibit IRS from mupirocin-resistant staphylococci, indicating that SB 205952 has more than one mechanism of action. SB 205952 rapidly inhibits protein, RNA, and DNA syntheses in mupirocin-susceptible and mupirocin-resistant staphylococci. In each case, the effect on RNA synthesis is relaxed by treatment with chloramphenicol, indicating that inhibition of RNA synthesis is probably a secondary consequence of stringent control. It is proposed that SB 205952 possesses one or more mechanisms of action in addition to IRS inhibition, probably mediated by its nitrofuryl component.