<p>PAU-1, a Novel Plasmid-Encoded Ambler Class A β-Lactamase Identified in a Clinical <em>Pseudomonas aeruginosa</em> Isolate</p>

Abstract

PurposeThe aim of this work was to identify a novel β-lactamase gene blaPAU-1 encoded on the plasmid of a clinical Pseudomonas aeruginosa isolate.Materials and methodsThe clinical P. aeruginosa isolates were isolated from a hospital in southern China. Molecular cloning was performed to analyze the function of the resistance gene. The minimum inhibitory concentration (MIC) was determined by means of the agar dilution method to determine the antimicrobial susceptibilities of the strains. Whole-genome sequencing and comparative genomics analysis were performed to analyze the structures of the resistance gene-related sequences.ResultsPAU-1 is a molecular class A, Bush-Jacoby group 2be enzyme which encoded 293 amino acids and shared 74% amino acid identity with a putative class A β-lactamase from Rhodoferax saidenbachensis. Cloned blaPAU-1 in Escherichia coli and P. aeruginosa conferred resistance to piperacillin and ampicillin, and elevated the MIC with a 2–3 dilution for some oxyimino-β-lactams in P. aeruginosa. The genetic environment of blaPAU-1 is tnpA-res-hp-relE-blaPAU-1-lysR, which is in accordance with the structure of a Tn3 transposon. Epidemiological investigation of blaPAU-1 in the same district did not show any evidences of molecular dissemination associated with this determinant.ConclusionA novel class A β-lactamase gene, blaPAU-1, associated with the mobile genetic element was identified on a transferable plasmid in a clinical P. aeruginosa isolate. Strict surveillance for the emergence of the new determinant should be established and an effort should be made to block the dissemination of this determinant.

A new class A beta-lactamase gene blaCAE-1 coexists with blaAFM-1 in a novel untypable plasmid in Comamonas aquatica

“…Analysis of the adjacent genetic elements of bla CAE-1 in p1_SCLZS63 and the above four bla CAE-1 -carrying sequences showed that bla CAE-1 is always reversely located at the immediate upstream of the LysR family transcriptional activator-encoding gene ampR (Fig. 2 ), which consists with the commonly seen lysR -accompanied class A β-lactamases as described previously 36 . In all sequences except pB1A, the bla CAE-1 - ampR element is bounded by an intact IS caq2 (upstream of bla CAE-1 ) and a ΔIS caq2 (immediately downstream of bla CAE-1 ) that is truncated by a parallel IS caq1 (Fig.…”

“…The novel class A β-lactamase is most closely related to CzoA-1 35 (Accession no. EFI60385), with only 52.7% amino acid identity, followed by PAU-1 36 (48.8%, APC57487), and AXC-1 (48.3%, ATG32091) (Fig. 1 A).…”

Web-based Tool Validation for Antimicrobial Resistance Prediction: An Empirical Comparative Analysis

“…(46). In a prior study, it was discovered that a clinical isolate of Pseudomonas aeruginosa contained a transferable plasmid containing the gene known as blaPAU-1, which is connected to the mobile genetic element (47). Considering the high ubiquity of beta-lactam resistance genes, it is preferable to monitor the level of antibiotic resistance and resistance genes in patients with Pseudomonas aeruginosa infection (48).…”