title: Escherichia coli N-Acetylglucosamine-1-Phosphate-Uridyltransferase/Glucosamine-1-Phosphate-Acetyltransferase (GlmU) Inhibitory Activity of Terreic Acid Isolated from Aspergillus terreus.
abstract: Secondary metabolite of Aspergillus terreus, terreic acid, is a reported potent antibacterial that was identified more than 60 years ago, but its cellular target(s) are still unknown. Here we screen its activity against the acetyltransferase domain of a bifunctional enzyme, Escherichia coli N-acetylglucosamine-1-phosphate-uridyltransferase/glucosamine-1-phosphate-acetyltransferase (GlmU). An absorbance-based assay was used to screen terreic acid against the acetyltransferase activity of E. coli GlmU. Terreic acid was found to inhibit the acetyltransferase domain of E. coli GlmU with an IC50 of 44.24 ± 1.85 µM. Mode of inhibition studies revealed that terreic acid was competitive with AcCoA and uncompetitive with GlcN-1-P. It also exhibited concentration-dependent killing of E. coli ATCC 25922 up to 4× minimum inhibitory concentration and inhibited the growth of biofilms generated by E. coli. Characterization of resistant mutants established mutation in the acetyltransferase domain of GlmU. Terreic acid was also found to be metabolically stable in the in vitro incubations with rat liver microsome in the presence of a NADPH regenerating system. The studies reported here suggest that terreic acid is a potent antimicrobial agent and support that E. coli GlmU acetyltransferase is a molecular target of terreic acid, resulting in its antibacterial activity.
authors.affiliation: Clinical Microbiology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, India Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, India.
authors.forename: Rashmi
authors.initials: R
authors.lastname: Sharma
authors.affiliation: Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, India Natural Products Chemistry: Microbes, CSIR-Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu, India.
authors.forename: Mallikharjuna Rao
authors.initials: MR
authors.lastname: Lambu
authors.affiliation: Fermentation Technology Division, CSIR-Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu Tawi, India.
authors.forename: Urmila
authors.initials: U
authors.lastname: Jamwal
authors.affiliation: Clinical Microbiology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, India Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, India.
authors.forename: Chitra
authors.initials: C
authors.lastname: Rani
authors.affiliation: Clinical Microbiology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, India.
authors.forename: Reena
authors.initials: R
authors.lastname: Chib
authors.affiliation: Instrumentation Division, CSIR-Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu Tawi, India.
authors.forename: Priya
authors.initials: P
authors.lastname: Wazir
authors.affiliation: Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, India Natural Products Chemistry: Microbes, CSIR-Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu, India.
authors.forename: Debaraj
authors.initials: D
authors.lastname: Mukherjee
authors.affiliation: Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, India Fermentation Technology Division, CSIR-Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu Tawi, India.
authors.forename: Asha
authors.initials: A
authors.lastname: Chaubey
authors.affiliation: Clinical Microbiology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, India Academy of Scientific and Innovative Research, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, India iakhan@iiim.res.in inshad@rediffmail.com.
authors.forename: Inshad Ali
authors.initials: IA
authors.lastname: Khan
mesh_terms: D000105:Acetyl Coenzyme A / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001230:Aspergillus / Q000737:chemistry* / Q000378:metabolism; D001667:Binding, Competitive; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D001681:Biological Assay; D004791:Enzyme Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D029968:Escherichia coli Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D005944:Glucosamine / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D019298:Glucose-6-Phosphate / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D062105:Molecular Docking Simulation; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D011485:Protein Binding / Q000187:drug effects; D000072417:Protein Domains; D011809:Quinones / Q000302:isolation & purification / Q000494:pharmacology; D051381:Rats; D064210:Secondary Metabolism
chemical_list: D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D029968:Escherichia coli Proteins; C520333:GlmU protein, E coli; D009097:Multienzyme Complexes; D011809:Quinones; C001293:glucosamine 6-phosphate; D019298:Glucose-6-Phosphate; D000105:Acetyl Coenzyme A; D005944:Glucosamine; C009400:terreic acid
keywords: ESBL; GlmU; acetyltransferase; drug resistance; lipopolysaccharide