TY - JOUR
T1 - Inhibition of isolated Mycobacterium tuberculosis fatty acid synthase I by pyrazinamide analogs
AU - Ngo, Silvana C.
AU - Zimhony, Oren
AU - Woo, Jin Chung
AU - Sayahi, Halimah
AU - Jacobs, William R.
AU - Welch, John T.
PY - 2007/7
Y1 - 2007/7
N2 - An analog of pyrazinamide (PZA), 5-chloropyrazinamide (5-Cl-PZA), has previously been shown to inhibit mycobacterial fatty acid synthase I (FASI). FASI has been purified from a recombinant strain of M. smegmatis (M. smegmatis Δfas1 attB::M. tuberculosis fas1). Following purification, FASI activity and inhibition were assessed spectrophotometrically by monitoring NADPH oxidation. The observed inhibition was both concentration and structure dependent, being affected by both substitution at the 5 position of the pyrazine nucleus and the nature of the ester or N-alkyl group. Under the conditions studied, both 5-Cl-PZA and PZA exhibited concentration and substrate dependence consistent with competitive inhibition of FASI with Kis of 55 to 59 μM and 2,567 to 2,627 μM, respectively. The results were validated utilizing a radiolabeled fatty acid synthesis assay. This assay showed that FASI was inhibited by PZA and pyrazinoic acid as well as by a series of PZA analogs.
AB - An analog of pyrazinamide (PZA), 5-chloropyrazinamide (5-Cl-PZA), has previously been shown to inhibit mycobacterial fatty acid synthase I (FASI). FASI has been purified from a recombinant strain of M. smegmatis (M. smegmatis Δfas1 attB::M. tuberculosis fas1). Following purification, FASI activity and inhibition were assessed spectrophotometrically by monitoring NADPH oxidation. The observed inhibition was both concentration and structure dependent, being affected by both substitution at the 5 position of the pyrazine nucleus and the nature of the ester or N-alkyl group. Under the conditions studied, both 5-Cl-PZA and PZA exhibited concentration and substrate dependence consistent with competitive inhibition of FASI with Kis of 55 to 59 μM and 2,567 to 2,627 μM, respectively. The results were validated utilizing a radiolabeled fatty acid synthesis assay. This assay showed that FASI was inhibited by PZA and pyrazinoic acid as well as by a series of PZA analogs.
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U2 - 10.1128/AAC.01458-06
DO - 10.1128/AAC.01458-06
M3 - Article
C2 - 17485499
AN - SCOPUS:34447258829
SN - 0066-4804
VL - 51
SP - 2430
EP - 2435
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
IS - 7
ER -
