title: Identification of a novel fosfomycin-resistant UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) from a soil metagenome.
abstract: A soil metagenomic library was constructed and screened for clones that conferred fosfomycin resistance. A novel protein with 46 % identity to UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) from Desulfuromonas acetoxidans DSM 684 (GenBank accession number: ZP_01311756) was identified. Multiple sequence alignment revealed that the novel protein was a natural MurA, in which an aspartic acid instead of a cysteine was located in the active site. An Asp120Cys mutant of Escherichia coli was constructed from the subclone through site-specific mutagenesis, and minimum inhibitory concentration of fosfomycin for the resistant subclone and its mutant were determined. These results showed that fosfomycin resistance was a result of the aspartic acid in the active site. Analysis of all existing MurA sequences revealed that MurAs with an active site aspartic acid that can confer fosfomycin resistance occur in ~14 % of bacteria.
authors.affiliation: Microbial Genome Research Center, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China. chengg@im.ac.cn
authors.forename: Gong
authors.initials: G
authors.lastname: Cheng
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Hu
authors.forename: Na
authors.initials: N
authors.lastname: Lu
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Zhiyun
authors.initials: Z
authors.lastname: Wang
authors.forename: Quanze
authors.initials: Q
authors.lastname: Chen
authors.forename: Baoli
authors.initials: B
authors.lastname: Zhu
mesh_terms: D019883:Alkyl and Aryl Transferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D020134:Catalytic Domain / Q000235:genetics; D045287:Desulfuromonas / Q000235:genetics; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D005578:Fosfomycin / Q000494:pharmacology*; D054892:Metagenome; D008826:Microbial Sensitivity Tests; D016297:Mutagenesis, Site-Directed; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012988:Soil Microbiology
chemical_list: D000900:Anti-Bacterial Agents; D050505:Mutant Proteins; D005578:Fosfomycin; D019883:Alkyl and Aryl Transferases; C022566:UDP-N-acetylglucosamine 1-carboxyvinyltransferase