Screening systems for detecting inhibitors of cell wall transglycosylation in Enterococcus. Cell wall transglycosylation inhibitors in Enterococcus.
We devised two screening systems to detect cell wall transglycosylation inhibitors. One screen utilizes a mutant of Enterococcus faecalis strain A256 that is dependent on vancomycin or moenomycin for growth. In the absence of transglycosylation inhibitors the strain fails to grow, while in the presence of inhibitors, cells are rescued. A second screening organism E. faecalis strain MDD212 utilizes a translational fusion of the lacZ gene to the vanH promoter in a derivative of E. faecalis that contains a vancomycin resistance determinant. Induction of beta-galactosidase occurs when cells are exposed to inhibitors of transglycosylation. Our natural products drug source of fungal fermentations was tested with these screens. Several cultures that produced the same family of compounds, called the thielavins, were detected. Thielavin B inhibited the formation of peptidoglycan in an in vitro assay, suggesting that these screening systems can detect compounds that interfere with cell wall transglycosylation.
Drug discovery department, Millennium Pharmaceuticals, Cambridge, MA 02139, USA.
N
N
Mani
P
P
Sancheti
Z D
ZD
Jiang
C
C
McNaney
M
M
DeCenzo
B
B
Knight
M
M
Stankis
M
M
Kuranda
D M
DM
Rothstein
P
P
Sanchet
B
B
Knighti
D001483:Base Sequence; D002473:Cell Wall / Q000187:drug effects*; D013293:Enterococcus faecalis / Q000187:drug effects*; D005285:Fermentation; D006031:Glycosylation; D062385:Hydroxybenzoates / Q000737:chemistry / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009838:Oligodeoxyribonucleotides; D014640:Vancomycin / Q000494:pharmacology
D062385:Hydroxybenzoates; D009838:Oligodeoxyribonucleotides; D014640:Vancomycin; C033795:thielavin B