Michelle J Cole1, Magnus Unemo2, Vlad Grigorjev3, Nerteley Quaye4, Neil Woodford5. 1. Sexually Transmitted Bacteria Reference Unit, Public Health England, London, UK michelle.cole@phe.gov.uk. 2. WHO Collaborating Centre for Gonorrhoea and other STIs, National Reference Laboratory for Pathogenic Neisseria, Department of Laboratory Medicine, Microbiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden. 3. Sexually Transmitted Bacteria Reference Unit, Public Health England, London, UK. 4. National Mycobacterium Reference Laboratory, Public Health England, London, UK. 5. Antimicrobial Resistance and Healthcare Associated Infections Reference Unit, Public Health England, London, UK.
Abstract
OBJECTIVES: The objective of this study was to investigate the genetic diversity of blaTEM alleles, antimicrobial susceptibility and molecular epidemiological characteristics of penicillinase-producing Neisseria gonorrhoeae (PPNG) isolates collected in 2012 from England and Wales. METHODS: PPNG isolates were from the 2012 Gonococcal Resistance to Antimicrobial Surveillance Programme (GRASP). Their susceptibility to seven antimicrobials was determined using agar dilution methodology. β-Lactamase production was detected using a nitrocefin test. β-Lactamase plasmid types were determined and blaTEM genes were sequenced. Isolates were also typed by N. gonorrhoeae multi-antigen sequence typing (NG-MAST). RESULTS: Seventy-three PPNG isolates were identified in the 2012 GRASP collection (4.6%, 73/1603). Three different blaTEM alleles were identified, encoding three TEM amino acid sequences: TEM-1 (53%), TEM-1 with a P14S substitution (19%) and TEM-135 (27%). The blaTEM-135 allele was present in nine different NG-MAST types and was found mostly on Asian (60%) and Toronto/Rio (35%) plasmids. By contrast, most TEM-1-encoding plasmids were African (98%). All the TEM-135 isolates displayed high-level ciprofloxacin and tetracycline resistance. CONCLUSIONS: The high proportion of blaTEM-135 alleles (27%) demonstrates that this variant is circulating within several gonococcal lineages. Only a single specific mutation near the β-lactamase active site could result in TEM-135 evolving into an ESBL. This is concerning particularly because the TEM-135 isolates were associated with high-level ciprofloxacin and tetracycline resistance. It is encouraging that no further TEM alleles were detected in this gonococcal population; however, vigilance is vital as an ESBL in N. gonorrhoeae would render the last remaining option for monotherapy, ceftriaxone, useless.
OBJECTIVES: The objective of this study was to investigate the genetic diversity of blaTEM alleles, antimicrobial susceptibility and molecular epidemiological characteristics of penicillinase-producing Neisseria gonorrhoeae (PPNG) isolates collected in 2012 from England and Wales. METHODS: PPNG isolates were from the 2012 Gonococcal Resistance to Antimicrobial Surveillance Programme (GRASP). Their susceptibility to seven antimicrobials was determined using agar dilution methodology. β-Lactamase production was detected using a nitrocefin test. β-Lactamase plasmid types were determined and blaTEM genes were sequenced. Isolates were also typed by N. gonorrhoeae multi-antigen sequence typing (NG-MAST). RESULTS: Seventy-three PPNG isolates were identified in the 2012 GRASP collection (4.6%, 73/1603). Three different blaTEM alleles were identified, encoding three TEM amino acid sequences: TEM-1 (53%), TEM-1 with a P14S substitution (19%) and TEM-135 (27%). The blaTEM-135 allele was present in nine different NG-MAST types and was found mostly on Asian (60%) and Toronto/Rio (35%) plasmids. By contrast, most TEM-1-encoding plasmids were African (98%). All the TEM-135 isolates displayed high-level ciprofloxacin and tetracycline resistance. CONCLUSIONS: The high proportion of blaTEM-135 alleles (27%) demonstrates that this variant is circulating within several gonococcal lineages. Only a single specific mutation near the β-lactamase active site could result in TEM-135 evolving into an ESBL. This is concerning particularly because the TEM-135 isolates were associated with high-level ciprofloxacin and tetracycline resistance. It is encouraging that no further TEM alleles were detected in this gonococcal population; however, vigilance is vital as an ESBL in N. gonorrhoeae would render the last remaining option for monotherapy, ceftriaxone, useless.
Authors: Nathan Mullen; Hugo Raposo; Polyxeni Gudis; Linsey Barker; Romney M Humphries; Bryan H Schmitt; Ryan F Relich; Meghan May Journal: mSphere Date: 2017-07-19 Impact factor: 4.389
Authors: Ilya Kandinov; Dmitry Gryadunov; Alexandra Vinokurova; Olga Antonova; Alexey Kubanov; Victoria Solomka; Julia Shagabieva; Dmitry Deryabin; Boris Shaskolskiy Journal: Front Microbiol Date: 2022-06-20 Impact factor: 6.064