Target gene sequencing to characterize the penicillin G susceptibility of Neisseria meningitidis.
Clinical isolates of Neisseria meningitidis with reduced susceptibility to penicillin G (intermediate isolates, Pen(I)) harbor alterations in the penA gene encoding the penicillin binding protein 2 (PBP2). A 402-bp DNA fragment in the 3' half of penA was sequenced from a collection of 1,670 meningococcal clinical isolates from 22 countries that spanned 60 years. Phenotyping, genotyping, and the determination of MICs of penicillin G were also performed. A total of 139 different penA alleles were detected with 38 alleles that were highly related, clustered together in maximum-likelihood analysis and corresponded to the penicillin G-susceptible isolates. The remaining 101 penA alleles were highly diverse, corresponded to different genotypes or phenotypes, and accounted for 38% of isolates, but no clonal expansion was detected. Analysis of the altered alleles that were represented by at least five isolates showed high correlation with the Pen(I) phenotype. The deduced amino acid sequence of the corresponding PBP2 comprised five amino acid residues that were always altered. This correlation was not complete for rare alleles, suggesting that other mechanisms may also be involved in conferring reduced susceptibility to penicillin. Evidence of mosaic structures through events of interspecies recombination was also detected in altered alleles. A new website was created based on the data from this work (http://neisseria.org/nm/typing/penA). These data argue for the use of penA sequencing to identify isolates with reduced susceptibility to penicillin G and as a tool to improve typing of meningococcal isolates, as well as to analyze DNA exchange among Neisseria species.
Taha
Muhamed-Kheir
MK
Neisseria Unit, Institut Pasteur, 28 Rue du Dr Roux, Paris, France. mktaha@pasteur.fr
Vázquez
Julio A
JA
Hong
Eva
E
Bennett
Desiree E
DE
Bertrand
Sophie
S
Bukovski
Suzana
S
Cafferkey
Mary T
MT
Carion
Françoise
F
Christensen
Jens Jørgen
JJ
Diggle
Mathew
M
Edwards
Giles
G
Enríquez
Rocío
R
Fazio
Cecilia
C
Frosch
Matthias
M
Heuberger
Sigrid
S
Hoffmann
Steen
S
Jolley
Keith A
KA
Kadlubowski
Marcin
M
Kechrid
Amel
A
Kesanopoulos
Konstantinos
K
Kriz
Paula
P
Lambertsen
Lotte
L
Levenet
Ileanna
I
Musilek
Martin
M
Paragi
Metka
M
Saguer
Aouatef
A
Skoczynska
Anna
A
Stefanelli
Paola
P
Thulin
Sara
S
Tzanakaki
Georgina
G
Unemo
Magnus
M
Vogel
Ulrich
U
Zarantonelli
Maria Leticia
ML
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D005798:Genes, Bacterial; D005838:Genotype; D014943:Global Health; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D008969:Molecular Sequence Data; D009345:Neisseria meningitidis / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D010400:Penicillin G / Q000494:pharmacology*; D010403:Penicillin Resistance; D046915:Penicillin-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA
D000900:Anti-Bacterial Agents; D046915:Penicillin-Binding Proteins; D010400:Penicillin G