Carbapenems are Wide spectrum, β lactam class of antibiotic drug of last resort available as: imipenam, meropenam, doripenam and ertapenam. However, resistance to these drugs is emerging and may be mediated through: Efflux mechanism, Loss of porins, Change/ alterations in PBPs and specific β-lactamases - commonly known as carbapenamases.
PCR based Detection of Carbapenamases: Different primers and their utility
1. PCR based detection of
Carbapenamases:
Different primers and their
utility
Philma Glora. M
&
Bhoj R Singh
Division of Epidemiology
Indian veterinary Research Institute,
Izatnagar- 243 122, India
2. Carbapenams
Wide spectrum, β lactam class of antibiotics
Drug of last resort available as: imipenam, meropenam,
doripenam and ertapenam.
Resistance to these drugs is emerging and may be
mediated through:
Efflux mechanism.
Loss of porins.
Change/ alterations in PBPs.
βlactamases - common (carbapenamases): These are
classified in to 4 Classes.
3. Class A Carbapenemases
Serine residue at active site of enzyme
Plasmid/chromosome
Generally inhibited by clavulanic acid
Examples
Chromosomally encoded Plasmid encoded
SME (Serratia marcescens enzyme) GES (Guiana extended spectrum)
NMC (Non-metalloenzyme carbapenamase) KPC (Klebsiella pneumoniae carbapenamase)
IMI (Imipenam hydrolyzing β-lactamase)
4. Class B Carbapenemases
Zn at enzyme active site
Inhibited by EDTA
Located in integrons/plasmid
Examples
VIM (Verona integron encoded β-lactamase)
SMP (Sao Paulo metallo β-lactamase)
NDM1 (New Delhi metallo β-lactamase)
IMP (Active on Imipenam)
5. Class C Carbapenemases
Low potential of carbapenam resistance when combined
with efflux mechanism over expression
pYMG-1
Class D Carbapenemases
Oxacillin hydrolysis
Serine at active site of enzyme
Plasmid encoded
Common in Acinetobacter spp.
Poorly inhibited by EDTA and clavulanic acid
Examples-OX-23, OX-48
6. Class Producer
Organisms
Hydrolysis profile of the enzymes
Penicillin Early
cephalosporins
Extended
Spectrum
cephalosporins
Aztreonam Carbapenams
A Member of
Enterobacteri
aceae,
Pseudomonas,
Klebsiella
+ + + + (except
GES)
+
B Pseudomonas,
members of
Enterobacteri
aceae,
Acinetobacter
+ + + - +
D Acinetobacter + + ± - ±
7. Detection of Carbapenemases withPCR
Nucleic acid-based detection systems: Rapid and
sensitive to detect the presence of resistance genes.
Play a critical role in the elucidation of resistance
mechanisms & molecular epidemiology.
PCR involves cycles of heating the sample for
denaturing, annealing of the primers, and elongation
of the primers by a thermostable DNA polymerase.
8. Enzyme
Family/
Gene
Primer Primer Sequence (5’-3’) Fragment
Size (bp)
Entire
coding
region
Reference
Class A Carbapenameses
NMC NMC1
NMC4
GCATTGATATACCTTTAGCAGAGA
CGGTGATAAAATCACACTGAGCATA
2,158 Yes Radice et al.,
2004
SME IRS-5
IRS-6
AGATAGTAAATTTTATAG
CTCTAACGCTAATAG
1,138 Yes Queenan et
al., 2000
IMI IMI-A
IMI-B
ATAGCCATCCTTGTTTAGCTC
TCTGCGATTACTTTATCCTC
818 No Aubron et al.,
2004
KPC KPC forward
KPC reverse
ATGTCACTGTATCGCCGTCT
TTTTCAGAGCCTTACTGCCC
893 Yes Bradford et
al., 2004
GES GES-C
GES-D
GTTTTGCAATGTGCTCAACG
TGCCATAGCAATAGGCGTAG
371 No Weldhagen et
al., 2004
9. Enzyme
Family/
Gene
Primer Primer Sequence (5’-3’) Fragment
Size (bp)
Entire
coding
region
Reference
Class B Metalloenzymes
IMP Forward
Reverse
CTACCGCAGCAGAGTCTTTG
AACCAGTTTTGCCTTACCAT
587 Senda et al.,
1996
IMP-1 Forward
Reverse
TGAGCAAGTTATCTGTATTC
TTAGTTGCTTGGTTTTGATG
740 Yes Yan et al.,
2001
IMP-2 Forward
Reverse
GGCAGTCGCCCTAAAACAAA
TAGTTACTTGGCTGTGATGG
737 Yes Yan et al.,
2001
VIM Forward
Reverse
TCTACATGACCGCGTCTGTC
TGTGCTTTGACAACGTTCGC
748 Poirel et al.,
2000
VIM-1 Forward
Reverse
TTATGGAGCAGCAACCGATGT
CAAAAGTCCCGCTCCAACGA
920 Yes Yan et al.,
2001
VIM-2 Forward
Reverse
AAAGTTATGCCGCACTCACC
TGCAACTTCATGTTATGCCG
865 Yes Yan et al.,
2001
10. Enzyme
Family/
Gene
Primer Primer Sequence (5’-3’) Fragment
Size (bp)
Entire
coding
region
Reference
Class B Metalloenzymes
SPM-1 SPM-1F
SPM-1R
CCTACAATCTAACGGCGACC
CCTACAATCTAACGGCGACC
650 No Castanheira et
al., 2004
GIM-1 GIM-1F
GIM-1R
AGAACCTTGACCGAACGCAG
ACTCATGACTCCTCACGAGG
748 No Castanheira et
al., 2004
SIM-1 SIM-1F
SIM-1R
TACAAGGGATTCGGCATCG
TAATGGCCTGTTCCCATGTG
571 No Lee et al.,
2002
NDM-1 Forward
Reverse
GGTTTGGCGATCTGGTTTTC
CGGAATGGCTCATCACGATC
621 Nordmann et
al., 2011
Integron
PCR
5’CS
3’CS
GGCATCCAAGCAGCAAG
AAGCAGACTTGACCTGA
Variable Levesque et
al., 1995
11. Enzyme
Family/
Gene
Primer Primer Sequence (5’-3’) Fragment Size
(bp)
Entire
coding
region
Reference
Class D Oxacillinases
OXA forward
reverse
ATG GCA ATC CGA ATC TTC G
TTA TCG CGC AGC GTC CGA G
Mohammed
Shahid et al.,
2012
OXA-23 P5
P6
AAGCATGATGAGCGCAAAG
AAAAGGCCCATTTATCTCAAA
1,066 Yes Donald et al.,
2000
OXA-24 Forward
Reverse
GTACTAATCAAAGTTGTGAA
TTCCCCTAACATGAATTTGT
1023 Yes Afzal-Shah et al
1998
OXA-69 OXA-69A
OXA-69B
CTAATAATTGATCTACTCAAG
CCAGTGGATGGATGGATAGATTATC
975 Yes Heritier et al.,
2005a
OXA-58 Pre-OXA-
58prom+
Pre-OXA-
58B
TTATCAAAATCCAATCGGC
TAACCTCAAACTTCTAATTC
934 Yes Heritier et al.,
2005b
Shewanella
OXA-55
OXA-55/1
0XA-55/2
CATCTACCTTTAAAATTCCC
AGCTGTTCCTGCTTGAGCAC
875 Yes Heritier et al.,
2004
12. Enzyme
Family/
Gene
Primer Primer Sequence (5’-3’) Fragment
Size (bp)
Entire
coding
region
Reference
Class D Oxacillinases
OXA-48 OXA-48A
OXA-48B
TTGGTGGCATCGATTATCGG
GAGCACTTCTTTTGTGATGGC
744 No Poirel et al.,
2004
OXA-50 S
AS
AATCCGGCGCTCATCCATC
GGTCGGCGACTGAGGCGG
869 Yes Girlich et al.,
2004a
OXA-60 OXA-60A
OXA-60B
AAAGGAGTTGTCTCATGCTGTCTCG
AACCTACAGGCGCGCGTCTCACGGTG
353 Yes Girlich et al.,
2004b
13. Multiplex PCR for OxAs in
Acinetobacter baumannii
Gene Primer (5’-3’)
OXA-51-like TAATGCTTTGATCGGCCTTG
TGGATTGCACTTCATCTTGG
OXA-23-like GATCGGATTGGAGAACCAGA
ATTTCTGACCGCATTTCCAT
OXA-24-like GGTTAGTTGGCCCCCTTAAA
AGTTGAGCGAAAAGGGGATT
OXA-58-like AAGTATTGGGGCTTGTGCTG
CCCCTCTGCGCTCTACATAC
Woodford et al., 2006