Table 1. Antibiotic resistance genes of Vietnamese extended-spectrum β-lactamase (VEB)-producing Klebsiella pneumoniae clinical strains and Escherichia coli transconjugant clones.
| Characteristics | T-970/19 | TrcT-970 | E-1037/19 | TrcE-1037 | TrcS-2865 |
|---|---|---|---|---|---|
| Affected antibiotic class | Resistance genes per isolate | ||||
| Aminoglycosides | aadA1 | aadA1 | aadA1 | aadA1 | aadA1 |
| aadA2 | aadA2 | aadA2 | NP | NP | |
| ant(2”)-Ia | ant(2”)-Ia | ant(2”)-Ia | ant(2”)-Ia | ant(2”)-Ia | |
| aph(3”)-Ia | aph(3”)-Ia | aph(3”)-Ia | NP | NP | |
| aph(3”)-Ib | aph(3”)-Ib | aph(3”)-Ib | aph(3”)-Ib | aph(3”)-Ib | |
| aph(6)-Id | aph(6)-Id | aph(6)-Id | aph(6)-Id | aph(6)-Id | |
| rmtB1 | rmtB1 | rmtB1 | rmtB1 | rmtB1 | |
| NP | NP | aac(6')-Ib-cr | NP | NP | |
| β-lactams | blaKPC-2 | NP | blaKPC-3 | NP | NP |
| blaVEB-25 | blaVEB-25 | blaVEB-25 | blaVEB-25 | blaVEB-1 | |
| blaOXA-10 | blaOXA-10 | blaOXA-10 | blaOXA-10 | blaOXA-10 | |
| blaTEM-1 | blaTEM-1 | blaTEM-1 | blaTEM-1 | blaTEM-1 | |
| blaSHV-11 | NP | blaSHV-182 | NP | NP | |
| Fluoroquinolones (PMQR) | oqxA | NP | oqxA | NP | NP |
| oqxB | NP | oqxB | NP | NP | |
| Fosfomycin | fosA | fosA | fosA | NP | NP |
| Macrolides | mdf(A) | mdf(A) | mdf(A) | mdf(A) | mdf(A) |
| NP | NP | mph(A) | NP | NP | |
| Phenicol | cmlA1 | cmlA1 | cmlA1 | cmlA1 | cmlA1 |
| floR2 | floR2 | floR2 | floR2 | floR | |
| NP | NP | catA1 | NP | NP | |
| Rifampicin | arr-2 | arr-2 | arr-2 | arr-2 | arr-2 |
| Sulfonamide | sul1 | sul1 | sul1 | sul1 | sul1 |
| sul2 | sul2 | sul2 | sul2 | sul2 | |
| Tetracycline | tet(A) | tet(A) | tet(A) | tet(A) | tet(A) |
| tet(G) | tet(G) | tet(G) | tet(G) | tet(G) | |
| Trimethoprim | dfrA12 | dfrA12 | dfrA12 | NP | NP |
| NP | NP | dfrA14 | dfrA14 | dfrA14 | |
| NP | NP | dfrA23 | dfrA23 | dfrA23 | |
| Plasmid replicon types | Plasmid replicon types per isolate | ||||
| IncA/C2 IncR, IncFIB(pKPHS1), IncFIB(pQil), IncFII(K) |
IncA/C2 IncR |
IncA/C2 | IncA/C2 | IncA/C2 | |
| IncR | IncR | NP | NP | NP | |
| IncFIB(pKPHS1) | NP | IncFIB(K) | NP | NP | |
| IncFIB(pQil) | NP | ColRNAI | NP | NP | |
| IncFII(K) | NP | IncX3 | NP | NP | |
NP: Not present; KPC: Klebsiella pneumoniae carbapenemase; OXA: oxacillinase; PMQR: plasmid-mediated quinolone resistance; SHV: sulfhydryl reagent variable β-lactamase; TEM: Temoniera β-lactamase; Trc: transconjugant; VEB: Vietnamese extended-spectrum β-lactamase.
T-970/19 and E-1037/19 are the VEB-producing Klebsiella pneumoniae clinical strains detected in this study. TrcT-970 and TrcE-1037 are the Escherichia coli transconjugant clones obtained by mating experiments using T-970/19 and E-1037/19 as donors and a β-lactam-susceptible E. coli K12 strain (26R793) as recipient.TrcS-2865 is a ceftazidime-avibactam-susceptible E. coli 26R793 transconjugant containing blaVEB-1, blaOXA-10 and blaTEM-1 that was used for control purposes.